Current Medical Diagnosis & Treatment 2015
Disorders of the Eyes & Lids
Paul Riordan-Eva, FRCOphth
Refractive errors are the most common cause of reduced clarity of vision (visual acuity) and may be a readily treatable component of poor vision in patients with other diagnoses.
Use of a pinhole will overcome most refractive errors and thus allows their identification as a cause of reduced visual acuity.
- Contact Lenses
Contact lenses are used mostly for correction of refractive errors, for which they provide better optical correction than glasses, as well as for management of diseases of the cornea, conjunctiva, or lids. Colored contact lenses are being used increasingly for cosmesis.
The major risk from contact lens wear is bacterial, amebic, or fungal corneal infection, potentially a blinding condition. Such infections occur more commonly with soft lenses, particularly extended wear, for which there is at least a fivefold increase in risk of corneal ulceration compared with daily wear. Contact lens wearers including those using lenses for cosmesis should be made aware of the risks they face and ways to minimize them, such as avoiding overnight wear or use of lenses past their replacement date and maintaining meticulous lens hygiene, including not using tap water or saliva for lens cleaning. Contact lenses should be removed whenever there is ocular discomfort or redness. Ophthalmologic care should be sought if symptoms persist.
When to Refer
Any contact lens wearer with an acute painful red eye must be referred emergently to an ophthalmologist.
American Academy of Ophthalmology Refractive Management/Intervention Panel. Preferred Practice Pattern® Guidelines – Summary Benchmark. Refractive errors & refractive surgery. San Francisco, CA: American Academy of Ophthalmology; 2013. Available at: http://one.aao.org/summary-benchmark-detail/refractive-errors--surgery-summary-benchmark-octob
Lee SY et al. Contact lens complications in an urgent-care population: the University of California, Los Angeles, Contact Lens Study. Eye Contact Lens. 2012 Jan;38(1):49–52. [PMID: 22157395]
Singh S et al. Colored cosmetic contact lenses: an unsafe trend in the younger generation. Cornea. 2012 Jul;31(7):777–9. [PMID: 22378117]
- Surgical Correction
Various surgical techniques are available for the correction of refractive errors, particularly nearsightedness. Laser corneal refractive surgery reshapes the middle layer (stroma) of the cornea with an excimer laser. Other refractive surgery techniques are extraction of the clear crystalline lens with insertion of a single vision, multifocal or accommodative intraocular lens; insertion of an intraocular lens without removal of the crystalline lens (phakic intraocular lens); intrastromal corneal ring segments (INTACS); collagen cross-linking; laser thermal keratoplasty; and conductive keratoplasty (CK). Topical atropine and pirenzepine, a selective muscarinic antagonist, and rigid contact lens wear during sleep (orthokeratology) are also being investigated for nearsightedness.
American Academy of Ophthalmology Refractive Management/Intervention Panel. Preferred Practice Pattern® Guidelines. Refractive errors & refractive surgery. San Francisco, CA: American Academy of Ophthalmology; 2013. Available at: http://one.aao.org/preferred-practice-pattern/refractive-errors--surgery-ppp-2013
Bastawrous A et al. Laser refractive eye surgery. BMJ. 2011 Apr 20;342:d2345. [PMID: 21508060]
DISORDERS OF THE LIDS & LACRIMAL APPARATUS
Hordeolum is a common staphylococcal abscess that is characterized by a localized red, swollen, acutely tender area on the upper or lower lid. Internal hordeolum is a meibomian gland abscess that usually points onto the conjunctival surface of the lid; external hordeolum or sty usually is smaller and on the margin.
Warm compresses are helpful. Incision may be indicated if resolution does not begin within 48 hours. An antibiotic ointment (bacitracin or erythromycin) applied to the eyelid every 3 hours may be beneficial during the acute stage. Internal hordeolum may lead to generalized cellulitis of the lid.
Chalazion is a common granulomatous inflammation of a meibomian gland that may follow an internal hordeolum. It is characterized by a hard, nontender swelling on the upper or lower lid with redness and swelling of the adjacent conjunctiva. If the chalazion is large enough to impress the cornea, vision will be distorted. Treatment is usually by incision and curettage but corticosteroid injection may also be effective.
Arbabi EM et al. Chalazion. BMJ. 2010 Aug 10;341:c4044. [PMID: 21155069]
Blepharitis is a common chronic bilateral inflammatory condition of the lid margins. Anterior blepharitis involves the eyelid skin, eyelashes, and associated glands. It may be ulcerative, because of infection by staphylococci, or seborrheic in association with seborrhea of the scalp, brows, and ears. Posterior blepharitis results from inflammation of the meibomian glands. There may be bacterial infection, particularly with staphylococci, or primary glandular dysfunction, in which there is a strong association with acne rosacea.
Symptoms are irritation, burning, and itching. In anterior blepharitis, the eyes are “red-rimmed” and scales or granulations can be seen clinging to the lashes. In posterior blepharitis, the lid margins are hyperemic with telangiectasias, and the meibomian glands and their orifices are inflamed. The lid margin is frequently rolled inward to produce a mild entropion, and the tears may be frothy or abnormally greasy.
Blepharitis is a common cause of recurrent conjunctivitis. Both anterior and, more particularly, posterior blepharitis may be complicated by hordeola or chalazia; abnormal lid or lash positions, producing trichiasis; epithelial keratitis of the lower third of the cornea; marginal corneal infiltrates; and inferior corneal vascularization and thinning.
Anterior blepharitis is usually controlled by cleanliness of the lid margins, eyebrows, and scalp. Scales should be removed from the lids daily with a hot wash cloth or a damp cotton applicator and baby shampoo. In acute exacerbations, an antistaphylococcal antibiotic eye ointment such as bacitracin or erythromycin is applied daily to the lid margins. Antibiotic sensitivity studies may be helpful in severe cases.
In mild posterior blepharitis, regular meibomian gland expression may be sufficient to control symptoms. Inflammation of the conjunctiva and cornea indicates a need for more active treatment, including long-term low-dose oral antibiotic therapy, usually with tetracycline (250 mg twice daily), doxycycline (100 mg daily), minocycline (50–100 mg daily) or erythromycin (250 mg three times daily), and possibly short-term topical corticosteroids, eg, prednisolone, 0.125% twice daily. Topical therapy with antibiotics such as ciprofloxacin 0.3% ophthalmic solution twice daily may be helpful but should be restricted to short courses.
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines. Blepharitis. San Francisco, CA: American Academy of Ophthalmology; 2013. Available at:http://one.aao.org/preferred-practice-pattern/blepharitis-ppp--2013
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines – Summary Benchmark. Blepharitis. San Francisco, CA: American Academy of Ophthalmology; 2013. Available at: http://one.aao.org/summary-benchmark-detail/blepharitis-summary-benchmark--october-2012
- Entropion & Ectropion
Entropion (inward turning of usually the lower lid) occurs occasionally in older people as a result of degeneration of the lid fascia, or may follow extensive scarring of the conjunctiva and tarsus. Surgery is indicated if the lashes rub on the cornea. Botulinum toxin injections may also be used for temporary correction of the involutional lower eyelid entropion of older people.
Ectropion (outward turning of the lower lid) is common with advanced age (Figure 7–1). Surgery is indicated if there is excessive tearing, exposure keratitis, or a cosmetic problem.
Figure 7–1. Involutional ectropion of right lower eyelid. (From M. Reza Vagefi and John H Sullivan. Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th edition. McGraw-Hill, 2011.)
Bedran EG et al. Ectropion. Semin Ophthalmol. 2010 May;25(3):59–65. [PMID: 20590414]
Ferreira IS et al. Trichiasis. Semin Ophthalmol. 2010 May;25(3):66–71. [PMID: 20590415]
Pereira MG et al. Eyelid entropion. Semin Ophthalmol. 2010 May;25(3):52–8. [PMID: 20590413]
Eyelid tumors are usually benign. Basal cell carcinoma is the most common malignant tumor. Squamous cell carcinoma, meibomian gland carcinoma, and malignant melanoma also occur. Surgery for any lesion involving the lid margin should be performed by an ophthalmologist or suitably trained plastic surgeon to avoid deformity of the lid. Otherwise, small lesions can often be excised by the nonophthalmologist. Histopathologic examination of eyelid tumors should be routine, since 2% of lesions thought to be benign clinically are found to be malignant. The Mohs technique of intraoperative examination of excised tissue is particularly valuable in ensuring complete excision so that the risk of recurrence is reduced. The role of vismodegib in the treatment of eyelid basal cell carcinoma is being investigated.
Dekmezian MS et al. Malignancies of the eyelid: a review of primary and metastatic cancers. Int J Dermatol. 2013 Aug;52(8):903–26. [PMID: 23869923]
Gill HS et al. Vismodegib for periocular and orbital basal cell carcinoma. JAMA Ophthalmol. 2013 Dec 1;131(12):1591–4. [PMID: 24136169]
Wang CJ et al. Clinicopathologic features and prognostic factors of malignant eyelid tumors. Int J Ophthalmol. 2013 Aug 18;6(4):442–7. [PMID: 23991375]
Dacryocystitis is infection of the lacrimal sac usually due to congenital or acquired obstruction of the nasolacrimal system. It may be acute or chronic and occurs most often in infants and in persons over 40 years. It is usually unilateral. The usual infectious organisms are Staphylococcus aureus and beta-hemolytic streptococci in acute dacryocystitis and S epidermidis, anaerobic streptococci, or Candida albicans in chronic dacryocystitis.
Acute dacryocystitis is characterized by pain, swelling, tenderness, and redness in the tear sac area; purulent material may be expressed. In chronic dacryocystitis, tearing and discharge are the principal signs, and mucus or pus may also be expressed.
Acute dacryocystitis responds well to systemic antibiotic therapy. Surgical relief of the underlying obstruction is usually done electively but may be performed urgently in acute cases. The chronic form may be kept latent with antibiotics, but relief of the obstruction is the only cure. In adults, the standard procedure for obstruction of the lacrimal drainage system is dacryocystorhinostomy, which involves surgical exploration of the lacrimal sac and formation of a fistula into the nasal cavity; if necessary, the procedure can be supplemented by nasolacrimal intubation. Congenital nasolacrimal duct obstruction is common and often resolves spontaneously. It can be treated by probing of the nasolacrimal system and supplemented by nasolacrimal intubation or balloon catheter dilation, if necessary. Dacryocystorhinostomy is rarely required.
Ali MJ et al. Clinical profile and management outcome of acute dacryocystitis: two decades of experience in a tertiary eye care center. Semin Ophthalmol. 2013 Oct 30. [Epub ahead of print] [PMID: 24171807]
American Academy of Ophthalmology Preferred Practice Pattern® Clinical Question. Nasolacrimal duct obstruction. San Francisco, CA: American Academy of Ophthalmology;2013.http://one.aao.org/clinical-questions/nasolacrimal-duct-obstruction-3
Pinar-Sueiro S et al. Dacryocystitis: systematic approach to diagnosis and therapy. Curr Infect Dis Rep. 2012 Jan 29. [Epub ahead of print] [PMID: 22286338]
Conjunctivitis is the most common eye disease. It may be acute or chronic. Most cases are due to viral or bacterial (including gonococcal and chlamydial) infection. Other causes include keratoconjunctivitis sicca, allergy, chemical irritants, and deliberate self-harm. The mode of transmission of infectious conjunctivitis is usually direct contact via fingers, towels, handkerchiefs, etc, to the fellow eye or to other persons. It may be through contaminated eye drops.
Conjunctivitis must be differentiated from acute uveitis, acute glaucoma, and corneal disorders (Table 7–1).
Table 7–1. The inflamed eye: Differential diagnosis of common causes.
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines. Conjunctivitis. San Francisco, CA: American Academy of Ophthalmology; 2013.http://one.aao.org/preferred-practice-pattern/conjunctivitis-ppp--2013
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines – Summary Benchmark. Conjunctivitis. San Francisco, CA: American Academy of Ophthalmology; 2013. http://one.aao.org/summary-benchmark-detail/conjunctivitis-summary-benchmark--october-2012
Azari AA et al. Conjunctivitis: a systematic review of diagnosis and treatment. JAMA. 2013 Oct 23;310(16):1721–9. [PMID: 24150468]
Goodman DM et al. JAMA patient page. Conjunctivitis. JAMA. 2013 May 22;309(20):2176. [PMID: 23695487]
- Viral Conjunctivitis
Adenovirus is the most common cause of viral conjunctivitis. There is usually bilateral disease with copious watery discharge, often with marked foreign body sensation, and a follicular conjunctivitis. Infection spreads easily. Eye clinics and contaminated swimming pools are sometimes the source of infection. Epidemic keratoconjunctivitis, which may result in visual loss due to corneal subepithelial infiltrates, is usually caused by adenovirus types 8, 19, and 37. The disease lasts at least 2 weeks. Infection with adenovirus types 3, 4, 7, and 11 is typically associated with pharyngitis, fever, malaise, and preauricular adenopathy (pharyngoconjunctival fever). The disease usually lasts 10 days. Viral conjunctivitis may also be due to herpes simplex virus (HSV), when it is usually unilateral and may be associated with lid vesicles, and enterovirus 70 or coxsackievirus A24 that characteristically cause acute hemorrhagic conjunctivitis (see Chapter 32).
Except for HSV infection for which treatment with topical (eg, ganciclovir 0.15% gel) and/or systemic (eg, oral acyclovir) antivirals is recommended, there is no specific treatment. Cold compresses reduce discomfort and topical sulfonamides (or oral antibiotics) can be prescribed to prevent secondary bacterial infection. The value of weak topical corticosteroids or topical cyclosporine for corneal infiltrates due to adenoviral infection is uncertain.
Kaufman HE. Adenovirus advances: new diagnostic and therapeutic options. Curr Opin Ophthalmol. 2011 Jul;22(4):290–3. [PMID: 21537185]
Skevaki CL et al. Treatment of viral conjunctivitis with antiviral drugs. Drugs. 2011 Feb 12;71(3):331–47. [PMID: 21319870]
- Bacterial Conjunctivitis
The organisms isolated most commonly in bacterial conjunctivitis are staphylococci, including methicillin-resistant S aureus (MRSA); streptococci, particularly S pneumoniae; Haemophilus species;Pseudomonas; and Moraxella. All may produce a copious purulent discharge. There is no blurring of vision and only mild discomfort. In severe (hyperpurulent) cases, examination of stained conjunctival scrapings and cultures is recommended, particularly to identify gonococcal infection.
The disease is usually self-limited, lasting about 10–14 days if untreated. A topical sulfonamide or oral antibiotic will usually clear the infection in 2–3 days. Except in special circumstances, the use of topical fluoroquinolones is rarely justified for treatment of a generally self-limiting, benign infection.
Epling J. Bacterial conjunctivitis. Clin Evid (Online). 2012 Feb 20;2012. [PMID: 22348418]
Sheikh A et al. Antibiotics versus placebo for acute bacterial conjunctivitis. Cochrane Database Syst Rev. 2012 Sep 12;(9):CD001211. [PMID: 22972049]
- Gonococcal Conjunctivitis
Gonococcal conjunctivitis, usually acquired through contact with infected genital secretions, typically causes copious purulent discharge. It is an ophthalmologic emergency because corneal involvement may rapidly lead to perforation. The diagnosis should be confirmed by stained smear and culture of the discharge. A single 1-g dose of intramuscular ceftriaxone is usually adequate. (Fluoroquinolone resistance is common.) Topical antibiotics such as erythromycin and bacitracin may be added. Other sexually transmitted diseases, including chlamydiosis, syphilis, and HIV infection, should be considered. Routine treatment for chlamydial infection is recommended.
Mayor MT et al. Diagnosis and management of gonococcal infections. Am Fam Physician. 2012 Nov 15;86(10):931–8. [PMID: 23157146]
- Chlamydial Keratoconjunctivitis
- Trachoma—Trachoma is the most common infectious cause of blindness worldwide, with approximately 40 million people affected and 1.3 million with profound vision loss. Recurrent episodes of infection in childhood manifest as bilateral follicular conjunctivitis, epithelial keratitis, and corneal vascularization (pannus). Cicatrization of the tarsal conjunctiva leads to entropion and trichiasis in adulthood, with secondary central corneal scarring.
Immunologic tests or polymerase chain reaction on conjunctival samples will confirm the diagnosis but treatment should be started on the basis of clinical findings. A single 1-g dose of oral azithromycin is the preferred drug treatment, but improvements in hygiene and living conditions probably have contributed more to the marked reduction in the prevalence of trachoma during the past 25 years. Local treatment is not necessary. Surgical treatment includes correction of eyelid deformities and corneal transplantation.
Bhosai SJ et al. Trachoma: an update on prevention, diagnosis, and treatment. Curr Opin Ophthalmol. 2012 Jul;23(4):288–95. [PMID: 22569465]
Taylor HR et al. Trachoma in Australia: an update. Clin Experiment Ophthalmol. 2013 Jul;41(5):508–12. [PMID: 23078264]
- Inclusion conjunctivitis—The agent of inclusion conjunctivitis is a common cause of genital tract disease in adults. The eye is usually involved following contact with genital secretions. The disease starts with acute redness, discharge, and irritation. The eye findings consist of follicular conjunctivitis with mild keratitis. A nontender preauricular lymph node can often be palpated. Healing usually leaves no sequelae. Diagnosis can be rapidly confirmed by immunologic tests or polymerase chain reaction on conjunctival samples. Treatment is with a single-dose of azithromycin, 1 g orally. Before treatment, all cases should be assessed for genital tract infection so that management can be adjusted accordingly, and other venereal diseases sought.
Malamos P et al. Evaluation of single-dose azithromycin versus standard azithromycin/doxycycline treatment and clinical assessment of regression course in patients with adult inclusion conjunctivitis. Curr Eye Res. 2013 Dec;38(12):1198–206. [PMID: 24047438]
Mishori R et al. Chlamydia trachomatis infections: screening, diagnosis, and management. Am Fam Physician. 2012 Dec 15;86(12):1127–32. [PMID: 23316985]
- Dry Eyes (Keratoconjunctivitis Sicca)
This is a common disorder, particularly in older women. Hypofunction of the lacrimal glands, causing loss of the aqueous component of tears, may be due to aging, hereditary disorders, systemic disease (eg, Sjögren syndrome), or systemic drugs. Excessive evaporation of tears may be due to environmental factors (eg, a hot, dry, or windy climate) or abnormalities of the lipid component of the tear film, as in blepharitis. Mucin deficiency may be due to vitamin A deficiency, or conjunctival scarring from trachoma, Stevens-Johnson syndrome and related conditions, mucous membrane pemphigoid, burns, or topical drugs or their preservatives.
The patient complains of dryness, redness, or foreign body sensation. In severe cases, there is persistent marked discomfort, with photophobia, difficulty in moving the eyelids, and often excessive mucus secretion. In many cases, inspection reveals no abnormality, but on slit-lamp examination there are subtle abnormalities of tear film stability and reduced volume of the tear film meniscus along the lower lid. In more severe cases, damaged corneal and conjunctival cells stain with 1% rose Bengal. In the most severe cases, there is marked conjunctival injection, loss of the normal conjunctival and corneal luster, epithelial keratitis that may progress to frank ulceration, and mucous strands. The Schirmer test, which measures the rate of production of the aqueous component of tears, may be helpful.
Aqueous deficiency can be treated with various types of artificial tears. The simplest preparations are physiologic (0.9%) or hypo-osmotic (0.45%) solutions of sodium chloride, which can be used as frequently as every half-hour, but in most cases are needed only three or four times a day. More prolonged duration of action can be achieved with drop preparations containing methylcellulose, polyvinyl alcohol, or polyacrylic acid (carbomers) or by using petrolatum ointment or a hydroxypropyl cellulose (Lacrisert) insert. Such mucomimetics are particularly indicated when there is mucin deficiency. If there is tenacious mucus, mucolytic agents (eg, acetylcysteine, 20% one drop six times daily) may be helpful. Autologous serum eye drops are used for severe dry eyes. Presumably due to its effects on ocular surface and lacrimal gland inflammation, cyclosporine (0.05% ophthalmic emulsion [Restasis] twice a day) has been shown to be beneficial in moderate and severe dry eyes with few adverse effects even in individuals treated for up to 4 years. Increased dietary intake of omega-3 fatty acids has been reported to be beneficial.
Lacrimal punctal occlusion by canalicular plugs or cautery is useful in severe cases. Blepharitis is treated as described above. Associated blepharospasm may benefit from botulinum toxin injections.
Artificial tear preparations are generally very safe and without side effects. Preservatives included in some preparations to maintain sterility are potentially toxic and allergenic and may cause keratitis and cicatrizing conjunctivitis in frequent users. The development of such reactions may be misinterpreted as a worsening of the dry eye state requiring more frequent use of the artificial tears and leading in turn to further deterioration, rather than being recognized as a need to change to a preservative-free preparation.
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines. Dry eye syndrome. San Francisco, CA: American Academy of Ophthalmology;2013.http://one.aao.org/preferred-practice-pattern/dry-eye-syndrome-ppp--2013
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines – Summary Benchmark. Dry eye syndrome. San Francisco, CA: American Academy of Ophthalmology;2013. http://one.aao.org/summary-benchmark-detail/dry-eye-syndrome-summary-benchmark--october-2012
Fraunfelder FT et al. The role of medications in causing dry eye. J Ophthalmol. 2012;2012:285851. [PMID: 23050121]
Tong L et al. Choice of artificial tear formulation for patients with dry eye: where do we start? Cornea. 2012 Nov;31(Suppl 1):S32–6. [PMID: 23038032]
Torpy JM et al. JAMA patient page. Dry eye. JAMA. 2012 Aug 8;308(6):632. [PMID: 22871877]
- Allergic Eye Disease
Allergic eye disease is common and takes a number of different forms but all are expressions of atopy, which may also manifest as atopic asthma, atopic dermatitis, or allergic rhinitis.
Symptoms include itching, tearing, redness, stringy discharge and, occasionally, photophobia and visual loss.
Allergic conjunctivitis is a benign disease, occurring usually in late childhood and early adulthood. It may be seasonal (hay fever), developing usually during the spring or summer, or perennial. Clinical signs are limited to conjunctival hyperemia and edema (chemosis), the latter at times being marked and sudden in onset. Vernal keratoconjunctivitis also tends to occur in late childhood and early adulthood. It is usually seasonal, with a predilection for the spring. Large “cobblestone” papillae are noted on the upper tarsal conjunctiva. There may be lymphoid follicles at the limbus. Atopic keratoconjunctivitis is a more chronic disorder of adulthood. Both the upper and the lower tarsal conjunctivas exhibit a fine papillary conjunctivitis with fibrosis, resulting in forniceal shortening and entropion with trichiasis. Staphylococcal blepharitis is a complicating factor. Corneal involvement, including refractory ulceration, is frequent during exacerbations of both vernal and atopic keratoconjunctivitis. The latter may be complicated by herpes simplex keratitis.
- Mild and Moderately Severe Allergic Eye Disease
Topical treatments include emedastine, epinastine, alcaftadine, ketotifen, or bepotastine (which have histamine H1-receptor antagonist, mast cell stabilizer, and eosinophil inhibitor activity) or ketorolac (a nonsteroidal anti-inflammatory drug) (Table 7–2). Olopatadine and azelastine reduce symptoms by similar mechanisms. Topical mast cell stabilizers, such as cromolyn, lodoxamide, nedocromil, and pemirolast produce longer-term prophylaxis but the therapeutic response may be delayed. Topical vasoconstrictors and antihistamines are of limited efficacy in allergic eye disease and may produce rebound hyperemia and follicular conjunctivitis. Systemic antihistamines (eg, loratadine 10 mg orally daily) may be useful in prolonged atopic keratoconjunctivitis. In allergic conjunctivitis, specific allergens may be avoidable. In vernal keratoconjunctivitis, a cooler climate often provides significant benefit.
Table 7–2. Topical ophthalmic agents.
- Acute Exacerbations and Severe Allergic Eye Disease
Topical corticosteroids (Table 7–2) are essential to the control of acute exacerbations of both vernal and atopic keratoconjunctivitis. Corticosteroid-induced side effects, including cataracts, glaucoma, and exacerbation of herpes simplex keratitis, are major problems but may be attenuated by the ester corticosteroid, loteprednol. Topical cyclosporine or tacrolimus is also effective. Systemic corticosteroid or other immunosuppressant therapy and even plasmapheresis may be required in severe atopic keratoconjunctivitis.
Kari O et al. Diagnostics and new developments in the treatment of ocular allergies. Curr Allergy Asthma Rep. 2012 Jun;12(3):232–9. [PMID: 22382607]
O’Brien TP. Allergic conjunctivitis: an update on diagnosis and management. Curr Opin Allergy Clin Immunol. 2013 Oct;13(5):543–9. [PMID: 23974684]
Sy H et al. Atopic keratoconjunctivitis. Allergy Asthma Proc. 2013 Jan–Feb;34(1):33–41. [PMID: 23406935]
PINGUECULA & PTERYGIUM
Pinguecula is a yellow elevated conjunctival nodule, more commonly on the nasal side, in the area of the palpebral fissure. It is common in persons over age 35 years. Pterygium is a fleshy, triangular encroachment of the conjunctiva onto the nasal side of the cornea and is usually associated with prolonged exposure to wind, sun, sand, and dust. Pinguecula and pterygium are often bilateral.
Pingueculae rarely grow but may become inflamed (pingueculitis). Pterygia become inflamed and may grow. No treatment is usually required for inflammation of pinguecula or pterygium, but artificial tears are often beneficial, and short courses of topical nonsteroidal anti-inflammatory agents or weak corticosteroids (loteprednol or fluorometholone four times a day) may be necessary.
The indications for excision of pterygium are growth that threatens vision by encroaching on the visual axis, marked induced astigmatism, or severe ocular irritation. Recurrence is common and often more aggressive than the primary lesion.
Liu T et al. Progress in the pathogenesis of pterygium. Curr Eye Res. 2013 Dec;38(12):1191–7. [PMID: 24047084]
Corneal ulcers are most commonly due to infection by bacteria, viruses, fungi, or amebas. Noninfectious causes—all of which may be complicated by infection—include neurotrophic keratitis (resulting from loss of corneal sensation), exposure keratitis (due to inadequate eyelid closure), severe dry eye, severe allergic eye disease, and various inflammatory disorders that may be purely ocular or part of a systemic vasculitis. Delayed or ineffective treatment of corneal ulceration may lead to devastating consequences with corneal scarring or intraocular infection. Prompt referral is essential.
Patients complain of pain, photophobia, tearing, and reduced vision. The eye is red, with predominantly circumcorneal injection, and there may be purulent or watery discharge. The corneal appearance varies according to the underlying cause.
When to Refer
Any patient with an acute painful red eye and corneal abnormality should be referred emergently to an ophthalmologist.
- Bacterial Keratitis
Bacterial keratitis usually pursues an aggressive course. Precipitating factors include contact lens wear—especially overnight wear—and corneal trauma, including refractive surgery. The pathogens most commonly isolated are Pseudomonas aeruginosa, Moraxella species, and other gram-negative bacilli; staphylococci, including MRSA; and streptococci. The cornea is hazy, with a central ulcer and adjacent stromal abscess. Hypopyon is often present. The ulcer is scraped to recover material for Gram stain and culture prior to starting treatment with high concentration topical antibiotic drops applied hourly day and night for at least the first 48 hours. Fluoroquinolones such as levofloxacin 0.5%, ofloxacin 0.3%, norfloxacin 0.3%, or ciprofloxacin 0.3% are commonly used as first-line agents as long as local prevalence of resistant organisms is low (Table 7–2). The fourth-generation fluoroquinolones (moxifloxacin 0.5% and gatifloxacin 0.3%) may be preferable because they are also active against mycobacteria. Gram-positive cocci can also be treated with a cephalosporin such as fortified cefazolin 10%, but vancomycin may be required for MRSA; and gram-negative bacilli can be treated with an aminoglycoside such as fortified tobramycin 1.5%. If no organisms are seen on Gram stain, these two agents can be used together in areas where resistance to fluoroquinolones is common. Adjunctive topical corticosteroid therapy should only be prescribed by an ophthalmologist.
When to Refer
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines. Bacterial keratitis. San Francisco, CA: American Academy of Ophthalmology; 2013.http://one.aao.org/preferred-practice-pattern/bacterial-keratitis-ppp--2013
American Academy of Ophthalmology Cornea/External Disease Panel. Preferred Practice Pattern® Guidelines – Summary Benchmark. Bacterial keratitis. San Francisco, CA: American Academy of Ophthalmology; 2013. http://one.aao.org/summary-benchmark-detail/bacterial-keratitis-summary-benchmark--october-201
Ray KJ et al. Fluoroquinolone treatment and susceptibility of isolates from bacterial keratitis. JAMA Ophthalmol. 2013 Mar;131(3):310–3. [PMID: 23307105]
Sharma N et al. Steroid associated infective keratitis—case studies for caution. Aust Fam Physician. 2011 Nov;40(11):888–90. [PMID: 22059219]
- Herpes Simplex Keratitis
Herpes simplex keratitis is an important cause of ocular morbidity. The ability of the virus to colonize the trigeminal ganglion leads to recurrences that may be precipitated by fever, excessive exposure to sunlight, or immunodeficiency.
The dendritic (branching) ulcer is the most characteristic manifestation. More extensive (“geographic”) ulcers also occur, particularly if topical corticosteroids have been used. These ulcers are most easily seen after instillation of fluorescein and examination with a blue light. Such epithelial disease in itself does not lead to corneal scarring. It responds well to simple debridement and patching. More rapid healing can be achieved by the addition of topical antivirals, such as trifluridine drops, ganciclovir gel, or acyclovir ointment (Table 7–2), or oral antivirals, such as acyclovir, 400 mg five times daily. Long-term oral acyclovir, 400 mg twice daily, or valacyclovir, 500 mg once daily, reduces the rate of recurrent epithelial disease, particularly in atopic individuals.
Stromal herpes simplex keratitis produces increasingly severe corneal opacity with each recurrence. Topical antivirals alone are insufficient to control stromal disease, so topical corticosteroids are used as well but they may enhance viral replication, exacerbating epithelial disease; steroid dependence is common. Oral acyclovir, 200–400 mg five times a day, is often helpful in the treatment of severe herpetic keratitis. The role of topical cyclosporine is being determined. Severe stromal scarring may require corneal grafting, but the overall outcome is relatively poor. Caution: For patients with known or possible herpetic disease, topical corticosteroids should be prescribed only with ophthalmologic supervision.
When to Refer
Any patient with a history of herpes simplex keratitis and an acute red eye should be referred urgently to an ophthalmologist.
American Academy of Ophthalmology Preferred Practice Pattern® Clinical Question. Herpes simplex virus epithelial keratitis. San Francisco, CA: American Academy of Ophthalmology; 2013.http://one.aao.org/clinical-questions/herpes-simplex-virus-epithelial-keratitis
Rowe AM et al. Herpes keratitis. Prog Retin Eye Res. 2013 Jan;32:88–101. [PMID: 22944008]
Sharma N et al. Steroid associated infective keratitis—case studies for caution. Aust Fam Physician. 2011 Nov;40(11):888–90. [PMID: 22059219]
- Herpes Zoster Ophthalmicus
Herpes zoster frequently involves the ophthalmic division of the trigeminal nerve. It presents with malaise, fever, headache, and periorbital burning and itching. These symptoms may precede the eruption by a day or more. The rash is initially vesicular, quickly becoming pustular and then crusting. Involvement of the tip of the nose or the lid margins predicts involvement of the eye. Ocular signs include conjunctivitis, keratitis, episcleritis, and anterior uveitis, often with elevated intraocular pressure. Recurrent anterior segment inflammation, neurotrophic keratitis, and posterior subcapsular cataract are long-term complications. Optic neuropathy, cranial nerve palsies, acute retinal necrosis, and cerebral angiitis occur infrequently. HIV infection is an important risk factor for herpes zoster ophthalmicus and increases the likelihood of complications.
High-dose oral acyclovir (800 mg five times a day), valacyclovir (1 g three times a day), or famciclovir (250–500 mg three times a day) started within 72 hours after the appearance of the rash reduces the incidence of ocular complications but not of postherpetic neuralgia. Anterior uveitis requires treatment with topical corticosteroids and cycloplegics. Neurotrophic keratitis is an important cause of long-term morbidity.
When to Refer
Any patient with herpes zoster ophthalmicus and ocular symptoms or signs should be referred urgently to an ophthalmologist.
Borkar DS et al. Incidence of herpes zoster ophthalmicus: results from the Pacific Ocular Inflammation Study. Ophthalmology. 2013 Mar;120(3):451–6. [PMID: 23207173]
Yawn BP et al. Herpes zoster eye complications: rates and trends. Mayo Clin Proc. 2013 Jun;88(6):562–70. [PMID: 23664666]
- Fungal Keratitis
Fungal keratitis tends to occur after corneal injury involving plant material or in an agricultural setting, in eyes with chronic ocular surface disease, and increasingly in contact lens wearers. It is usually an indolent process, with the cornea characteristically having multiple stromal abscesses and relatively little epithelial loss. Intraocular infection is common. Corneal scrapings should be cultured on media suitable for fungi whenever the history or corneal appearance is suggestive of fungal disease. Diagnosis is often delayed and treatment is difficult. Natamycin 5%, amphotericin 0.1-0.5%, and voriconazole 1% are the most commonly used topical agents. Systemic imidazoles may be helpful. Corneal grafting is often required.
Prajna NV et al. The mycotic ulcer treatment trial: a randomized trial comparing natamycin vs voriconazole. JAMA Ophthalmol. 2013 Apr;131(4):422–9. [PMID: 23710492]
Sharma S. Diagnosis of fungal keratitis: current options. Expert Opin Med Diagn. 2012 Sep;6(5):449–55. [PMID: 23480809]
Thomas PA et al. Mycotic keratitis: epidemiology, diagnosis and management. Clin Microbiol Infect. 2013 Mar;19(3):210–20. [PMID: 23398543]
- Acanthamoeba Keratitis
Acanthamoeba infection is an important cause of keratitis in contact lens wearers. Although severe pain with perineural and ring infiltrates in the corneal stroma is characteristic, it is not specific and earlier forms with changes confined to the corneal epithelium are identifiable. Diagnosis is facilitated by confocal microscopy. Culture requires specialized media. Long-term treatment is required because of the organism’s ability to encyst within the corneal stroma. Topical biguanides are probably the only effective primary treatment. Corneal grafting may be required after resolution of infection to restore vision. Systemic anti-inflammatory therapy is helpful if there is scleral involvement.
Clarke B et al. Advances in the diagnosis and treatment of Acanthamoeba keratitis. J Ophthalmol. 2012;2012:484892. [PMID: 23304449]
Kaiserman I et al. Prognostic factors in Acanthamoeba keratitis. Can J Ophthalmol. 2012 Jun;47(3):312–7. [PMID: 22687314]
Pacella E et al. Results of case-control studies support the association between contact lens use and Acanthamoeba keratitis. Clin Ophthalmol. 2013;7:991–4. [PMID: 23761962]
Page MA et al. Acanthamoeba keratitis: a 12-year experience covering a wide spectrum of presentations, diagnoses, and outcomes. J Ophthalmol. 2013;2013:670242. [PMID: 23840938]
ACUTE ANGLE-CLOSURE GLAUCOMA
ESSENTIALS OF DIAGNOSIS
Older age group, particularly farsighted individuals.
Rapid onset of severe pain and profound visual loss with “halos around lights.”
Red eye, cloudy cornea, dilated pupil.
Hard eye on palpation.
Primary acute angle-closure glaucoma (acute angle-closure crisis) occurs only with closure of a preexisting narrow anterior chamber angle, for which the predisposing factors are shallow anterior chamber, which may be associated with farsightedness or short stature (or both); enlargement of the crystalline lens with age causing further shallowing; and inheritance, being particularly prevalent among Inuits and Asians. It may be precipitated by pupillary dilation and thus can occur from sitting in a darkened theater, during times of stress, following nonocular administration of anticholinergic or sympathomimetic agents (eg, nebulized bronchodilators, atropine for preoperative medication, antidepressants, bowel or bladder antispasmodics, nasal decongestants, or tocolytics) or, rarely, from pharmacologic mydriasis (see Precautions in Management of Ocular Disorders, below). Secondary acute angle-closure glaucoma may occur in anterior uveitis or dislocation of the lens or due to various drugs paradoxically including acetazolamide (see Table 7–3). Symptoms are the same as in primary acute angle-closure glaucoma, but differentiation is important because of differences in management. Acute glaucoma, for which the mechanism may not be the same in all cases, can occur in association with hemodialysis. (Chronic angle-closure glaucoma presents in the same way as chronic open-angle glaucoma [see below]).
Table 7–3. Adverse ophthalmic effects of systemic drugs.
Patients with acute glaucoma usually seek treatment immediately because of extreme pain and blurred vision, though there are subacute cases. The blurred vision is associated with halos around lights. Nausea and abdominal pain may occur. The eye is red, the cornea cloudy, and the pupil moderately dilated and nonreactive to light. Intraocular pressure is usually over 50 mm Hg, producing a hard eye on palpation.
Acute glaucoma must be differentiated from conjunctivitis, acute uveitis, and corneal disorders (Table 7–1).
Initial treatment in acute glaucoma is reduction of intraocular pressure. A single 500-mg intravenous dose of acetazolamide, followed by 250 mg orally four times a day, together with topical medications is usually sufficient. Osmotic diuretics such as oral glycerin and intravenous urea or mannitol—the dosage of all three being 1–2 g/kg—may be necessary if there is no response to acetazolamide.
In primary acute angle-closure glaucoma, once the intraocular pressure has started to fall, topical 4% pilocarpine, 1 drop every 15 minutes for 1 hour and then four times a day, is used to reverse the underlying angle closure. The definitive treatment is laser peripheral iridotomy or surgical peripheral iridectomy. Cataract extraction is a possible alternative. If it is not possible to control the intraocular pressure medically, the angle closure may be overcome by corneal indentation, laser treatment (argon laser peripheral iridoplasty), cyclodiode laser treatment, or paracentesis; or by glaucoma drainage surgery as for uncontrolled open-angle glaucoma (see below).
All patients with primary acute angle-closure should undergo prophylactic laser peripheral iridotomy to the unaffected eye, unless that eye has already undergone cataract or glaucoma surgery. Whether prophylactic laser peripheral iridotomy should be undertaken in asymptomatic patients with narrow anterior chamber angles is uncertain and mainly influenced by the risk of the more common chronic angle-closure (see below).
In secondary acute angle-closure glaucoma, additional treatment is determined by the cause.
Untreated acute angle-closure glaucoma results in severe and permanent visual loss within 2–5 days after onset of symptoms. Affected patients need to be monitored for development of chronic glaucoma.
When to Refer
Any patient with suspected acute angle-closure glaucoma must be referred emergently to an ophthalmologist.
American Academy of Ophthalmology Glaucoma Panel. Preferred Practice Pattern® Guidelines. Primary open-angle closure glaucoma suspect. San Francisco, CA: American Academy of Ophthalmology; 2010. http://one.aao.org/preferred-practice-pattern/primary-openangle-glaucoma-suspect-ppp--october-20
American Academy of Ophthalmology Glaucoma Panel. Preferred Practice Pattern® Guidelines – Summary Benchmark. Primary angle closure. San Francisco, CA: American Academy of Ophthalmology; 2013. http://one.aao.org/summary-benchmark-detail/primary-angle-closure-summary-benchmark--october-2
Gracitelli CP et al. Ability of non-ophthalmologist doctors to detect eyes with occludable angles using the flashlight test. Int Ophthalmol. 2013 Oct 1. [Epub ahead of print] [PMID: 24081914]
Thomas R et al. Management algorithms for primary angle closure disease. Clin Experiment Ophthalmol. 2013 Apr;41(3):282–92. [PMID: 23009061]
White J. Diagnosis and management of acute angle-closure glaucoma. Emerg Nurse. 2011 Jun;19(3):27. [PMID: 21823566]
ESSENTIALS OF DIAGNOSIS
No symptoms in early stages.
Insidious progressive bilateral loss of peripheral vision, resulting in tunnel vision but preserved visual acuities until advanced disease.
Pathologic cupping of the optic disks.
Intraocular pressure is usually elevated.
Chronic glaucoma is characterized by gradually progressive excavation (“cupping”) and corresponding pallor of the optic disk with loss of vision progressing from slight visual field loss to complete blindness. In chronic open-angle glaucoma, primary or secondary, the intraocular pressure is elevated due to reduced drainage of aqueous fluid through the trabecular meshwork. In chronic angle-closure glaucoma, which is particularly common in Inuits and eastern Asians, flow of aqueous fluid into the anterior chamber angle is obstructed. In normal-tension glaucoma, intraocular pressure is not elevated but the same pattern of optic nerve damage occurs, probably due to vascular insufficiency.
Primary open-angle glaucoma is usually bilateral. There is an increased prevalence in first-degree relatives of affected individuals and in diabetic patients. In Afro-Caribbeans and Africans, and probably in Hispanics, it is more frequent, occurs at an earlier age, and results in more severe optic nerve damage. Secondary open-angle glaucoma may result from ocular disease, eg, pigment dispersion, pseudoexfoliation, uveitis, or trauma; or corticosteroid therapy, whether it is intraocular, topical, systemic, inhaled, or administered by nasal spray.
In the United States, it is estimated that 2% of people over 40 years of age have glaucoma, affecting over 2.5 million individuals. At least 25% of cases are undetected. Over 90% of cases are of the open-angle type. Worldwide, about 45 million people have open-angle-glaucoma, of whom about 4.5 million are bilaterally blind. About 4 million people, of whom approximately 50% live in China, are bilaterally blind from chronic angle-closure glaucoma.
Because initially there are no symptoms, chronic glaucoma is often suspected at a routine eye test. Diagnosis requires consistent and reproducible abnormalities in at least two of three parameters—optic disk or retinal nerve fiber layer (or both), visual field, and intraocular pressure. Optic disk cupping is identified as an absolute increase or an asymmetry between the two eyes of the ratio of the diameter of the optic cup to the diameter of the whole optic disk (cup-disk ratio). (Cup-disk ratio greater than 0.5 or 0.2 or more asymmetry between eyes is suggestive.) Detection of optic disk cupping and associated abnormalities of the retinal nerve fiber layer is facilitated by optical coherence tomography scans. Visual field abnormalities initially develop in the paracentral region, followed by constriction of the peripheral visual field. Central vision remains good until late in the disease. The normal range of intraocular pressure is 10–21 mm Hg. Its measurement is more complicated after corneal refractive surgery.
In many individuals (about 4.5 million in the United States), elevated intraocular pressure is not associated with optic disk or visual field abnormalities (ocular hypertension). Treatment to reduce intraocular pressure is justified if there is a moderate to high risk of progression to glaucoma, determined by several factors, including age, optic disk appearance, level of intraocular pressure, and corneal thickness, but monitoring for development of glaucoma is required in all cases. A significant proportion of eyes with primary open-angle glaucoma have normal intraocular pressure when it is first measured, and only repeated measurements identify the abnormally high pressure. In normal-tension glaucoma, intraocular pressure is always within the normal range.
There are many causes of optic disk abnormalities or visual field changes that mimic glaucoma and visual field testing may prove unreliable in some patients, particularly in the older age group. The diagnosis of glaucoma is not always straightforward and screening programs need to involve ophthalmologists.
Although all persons over age 50 years may benefit from intraocular pressure measurement and optic disk examination every 3–5 years, population-based screening for glaucoma is not cost-effective. Screening for chronic open-angle glaucoma should be targeted at individuals with an affected first-degree relative, at persons who have diabetes mellitus, and at older individuals with African or Hispanic ancestry. Screening may also be warranted in patients taking long-term oral or combined intranasal and inhaled corticosteroid therapy. Screening for chronic angle-closure glaucoma should be targeted at Inuits and Asians.
The prostaglandin analogs (bimatoprost 0.03%, latanoprost 0.005%, tafluprost 0.0015%, and travoprost 0.004% each used once daily at night, and unoprostone 0.15%, twice daily) are commonly used as first-line therapy because of their efficacy, their lack of systemic side effects, and the convenience of once-daily dosing (except unoprostone) (Table 7–2). All may produce conjunctival hyperemia, permanent darkening of the iris and eyebrow color, and increased eyelash growth. Latanoprost has been associated with reactivation of uveitis and macular edema.
Topical beta-adrenergic blocking agents (such as timolol 0.25% or 0.5%, carteolol 1% or 2%, levobunolol 0.5%, and metipranolol 0.3% solutions twice daily or timolol 0.1%, 0.25%, or 0.5% gel once daily) may be used alone or in combination with a prostaglandin analog. They are contraindicated in patients with reactive airway disease or heart failure. Betaxolol, 0.25% or 0.5%, a beta-receptor selective blocking agent, is theoretically safer in reactive airway disease but less effective at reducing intraocular pressure. Brimonidine 0.2%, a selective alpha-2-agonist, and dorzolamide 2% or brinzolamide 1%, topical carbonic anhydrase inhibitors, also can be used in addition to a prostaglandin analog or a beta-blocker (twice daily) or as initial therapy when prostaglandin analogs and beta-blockers are contraindicated (brimonidine twice daily, dorzolamide and brinzolamide three times daily). All three are associated with allergic reactions. Combination drops latanoprost 0.005% and timolol 0.5% (Xalacom), bimatoprost 0.03% and timolol 0.5% (Ganfort), and travoprost 0.004% and timolol 0.5% (DuoTrav), each used once daily, and dorzolamide 2% and timolol 0.5% (Cosopt), brinzolamide 1% and timolol 0.5% (Azarga), and brimonidine 0.2% and timolol 0.5% (Combigan), each used twice daily improve compliance when multiple medications are required.
Apraclonidine, 0.5–1%, another alpha-2-agonist, can be used three times a day to postpone the need for surgery in patients receiving maximal medical therapy, but long-term use is limited by drug reactions. It is more commonly used to control acute rises in intraocular pressure such as after laser therapy. Pilocarpine 1–4%, epinephrine, 0.5–1%, and the prodrug dipivefrin, 0.1%, are rarely used because of adverse effects. Oral carbonic anhydrase inhibitors (eg, acetazolamide) may still be used on a long-term basis if topical therapy is inadequate and surgical or laser therapy is inappropriate.
Formulations of topical agents without preservative or not including benzalkonium chloride as the preservative are available.
- Laser Therapy and Surgery
Laser trabeculoplasty is used as an adjunct to topical therapy to defer surgery and is also advocated as primary treatment. Surgery is generally undertaken when intraocular pressure is inadequately controlled by medical and laser therapy, but it may also be used as primary treatment. Trabeculectomy remains the standard procedure. Adjunctive treatment with subconjunctival mitomycin or fluorouracil is used perioperatively or postoperatively in difficult cases. Viscocanalostomy, deep sclerectomy with collagen implant and Trabectome—two alternative procedures that avoid a full-thickness incision into the eye—are associated with fewer complications but are less effective than trabeculectomy and more difficult to perform.
In chronic angle-closure glaucoma, laser peripheral iridotomy or surgical peripheral iridectomy may be helpful. In patients with asymptomatic narrow anterior chamber angles, which includes about 10% of Chinese adults, prophylactic laser peripheral iridotomy can be performed to reduce the risk of acute and chronic angle-closure glaucoma. However, there are concerns about the efficacy of such treatment and the risk of cataract progression and corneal decompensation. In the United States, about 1% of people over age 35 years have narrow anterior chamber angles, but acute and chronic angle-closure are sufficiently uncommon that prophylactic therapy is not generally advised.
Untreated chronic glaucoma that begins at age 40–45 years will probably cause complete blindness by age 60–65. Early diagnosis and treatment can preserve useful vision throughout life. In primary open-angle glaucoma—and if treatment is required in ocular hypertension—the aim is to reduce intraocular pressure to a level that will adequately reduce progression of visual field loss. In eyes with marked visual field or optic disk changes, intraocular pressure must be reduced to less than 16 mm Hg. In normal-tension glaucoma with progressive visual field loss, it is necessary to achieve even lower intraocular pressure such that surgery is often required.
When to Refer
All patients with suspected chronic glaucoma should be referred to an ophthalmologist.
American Academy of Ophthalmology Glaucoma Panel. Preferred Practice Pattern® Guidelines - Summary Benchmark. Primary open-angle glaucoma. San Francisco, CA: American Academy of Ophthalmology;2013. http://one.aao.org/summary-benchmark-detail/primary-openangle-glaucoma-summary- benchmark--octo
American Academy of Ophthalmology Glaucoma Panel. Preferred Practice Pattern® Guidelines - Summary Benchmark. Primary open-angle glaucoma suspect. San Francisco, CA: American Academy of Ophthalmology;2010. http://one.aao.org/summary-benchmark-detail/primary-openangle-glaucoma-suspect-summary-benchma
Burr J et al. Medical versus surgical interventions for open angle glaucoma. Cochrane Database Syst Rev. 2012 Sep 12;9:CD004399. [PMID: 22972069]
Peters D et al. Lifetime risk of blindness in open-angle glaucoma. Am J Ophthalmol. 2013 Oct;156(4):724–30. [PMID: 23932216]
Quigley HA. Glaucoma. Lancet. 2011 Apr 16;377(9774):1367–77. [PMID: 21453963]
ESSENTIALS OF DIAGNOSIS
Usually immunologic but possibly infective or neoplastic.
Acute nongranulomatous anterior uveitis: pain, redness, photophobia, and visual loss.
Granulomatous anterior uveitis: blurred vision in a mildly inflamed eye.
Posterior uveitis: gradual loss of vision in a quiet eye.
Intraocular inflammation (uveitis) is classified into acute or chronic, into nongranulomatous or granulomatous according to the clinical signs, and into anterior or posterior by its distribution—involving the anterior or posterior segments of the eye—or into panuveitis in which both segments are affected. The common types are acute nongranulomatous anterior uveitis, granulomatous anterior uveitis, and posterior uveitis.
In most cases, the pathogenesis of uveitis is primarily immunologic but infection may be the cause, particularly in immunodeficiency states. The systemic disorders associated with acute nongranulomatous anterior uveitis are the HLA-B27-related conditions (ankylosing spondylitis, reactive arthritis, psoriasis, ulcerative colitis, and Crohn disease). Chronic nongranulomatous anterior uveitis occurs in juvenile idiopathic arthritis. Behçet syndrome produces both anterior uveitis, with recurrent hypopyon but little discomfort, and posterior uveitis, characteristically with branch retinal vein occlusions. Both herpes simplex and herpes zoster infections may cause nongranulomatous anterior uveitis as well as retinitis (acute retinal necrosis), which has a very poor prognosis.
Diseases producing granulomatous anterior uveitis also tend to be causes of posterior uveitis. These include sarcoidosis, toxoplasmosis, tuberculosis, syphilis, Vogt-Koyanagi-Harada syndrome (bilateral uveitis associated with alopecia, poliosis [depigmented eyelashes, eyebrows, or hair], vitiligo, and hearing loss), and sympathetic ophthalmia that occurs after penetrating ocular trauma. In toxoplasmosis there may be evidence of previous episodes of retinochoroiditis. Syphilis characteristically produces a “salt and pepper” fundus but may present with a wide variety of clinical manifestations. The other principal pathogens responsible for ocular inflammation in HIV infection (see below) are cytomegalovirus (CMV), herpes simplex and herpes zoster viruses, mycobacteria, Cryptococcus, Toxoplasma, andCandida.
Autoimmune retinal vasculitis and pars planitis (intermediate uveitis) are idiopathic conditions that cause posterior uveitis.
Anterior uveitis is characterized by inflammatory cells and flare within the aqueous. In severe cases there may be hypopyon (layered collection of white cells) and fibrin within the anterior chamber. Cells may also be seen on the corneal endothelium as keratic precipitates (KPs). In granulomatous uveitis there are large “mutton-fat” KPs (Figure 7–2), and iris nodules may be seen. In nongranulomatous uveitis the KPs are smaller and iris nodules are not seen. The pupil is usually small, and with the development of posterior synechiae (adhesions between the iris and anterior lens capsule) it also becomes irregular.
Figure 7–2. Granulomatous keratic precipitates located on the inferior corneal endothelium. (From Emmett T Cunningham, Jr. Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr.Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
Nongranulomatous anterior uveitis tends to present acutely with unilateral pain, redness, photophobia, and visual loss. In juvenile idiopathic arthritis there tends to be an indolent often initially asymptomatic process with a high risk of sight-threatening complications. Granulomatous anterior uveitis is usually indolent, causing blurred vision in a mildly inflamed eye.
In posterior uveitis there are cells in the vitreous. Inflammatory lesions may be present in the retina or choroid. Fresh lesions are yellow with indistinct margins and there may be retinal hemorrhages, whereas older lesions have more definite margins and are commonly pigmented. Retinal vessel sheathing may occur adjacent to such lesions or more diffusely. In severe cases, vitreous opacity precludes visualization of retinal details.
Posterior uveitis tends to present with gradual visual loss in a relatively quiet eye. Bilateral involvement is common. Visual loss may be due to vitreous haze and opacities, inflammatory lesions involving the macula, macular edema, retinal vein occlusion, or rarely associated optic neuropathy.
Retinal detachment, intraocular tumors, and central nervous system lymphoma may all masquerade as uveitis.
Anterior uveitis usually responds to topical corticosteroids. Occasionally periocular corticosteroid injections or even systemic corticosteroids may be required. Dilation of the pupil is important to relieve discomfort and prevent posterior synechiae. Posterior uveitis more commonly requires systemic, periocular or intravitreal corticosteroid therapy and occasionally systemic immunosuppression with agents such as azathioprine, tacrolimus, cyclosporine, mycophenolate, or methotrexate, of which the last also can be administered by intraocular injection. The use of biologic therapies is increasing. Pupillary dilation is not usually necessary.
If an infectious cause is identified, specific antimicrobial therapy may be indicated. In general, the prognosis for anterior uveitis, particularly the nongranulomatous type, is better than for posterior uveitis.
When to Refer
- Any patient with suspected acute uveitis should be referred urgently to an ophthalmologist or emergently if visual loss or pain is severe.
- Any patient with suspected chronic uveitis should be referred to an ophthalmologist, urgently if there is more than mild visual loss.
When to Admit
Patients with severe uveitis, particularly those requiring intravenous therapy, may require hospital admission.
Deibel JP et al. Ocular inflammation and infection. Emerg Med Clin North Am. 2013 May;31(2):387–97. [PMID: 23601478]
Denniston AK et al. Systemic therapies for inflammatory eye disease: past, present and future. BMC Ophthalmol. 2013 Apr 24;13:18. [PMID: 23617902]
Jabs DA et al. Approach to the diagnosis of the uveitides. Am J Ophthalmol. 2013 Aug;156(2):228–36. [PMID: 23668682]
Kruh J et al. Corticosteroid-sparing agents: conventional systemic immunosuppressants. Dev Ophthalmol. 2012;51:29–46. [PMID: 22517202]
Lin P et al. The future of uveitis treatment. Ophthalmology. 2014 Jan;121(1):365–76. [PMID: 24169255]
ESSENTIALS OF DIAGNOSIS
Gradually progressive blurred vision.
No pain or redness.
Lens opacities (may be grossly visible).
Cataract is opacity of the crystalline lens. It is the leading cause of blindness worldwide, but access to treatment and quality of outcome are still limited in many areas. Cataracts are usually bilateral. They may be congenital (owing to intrauterine infections such as rubella and CMV, or inborn errors of metabolism such as galactosemia); traumatic; secondary to systemic disease (diabetes, myotonic dystrophy, atopic dermatitis), systemic or inhaled corticosteroid treatment, uveitis, or radiation exposure; or associated with other drugs, including statins; but age-related cataract is by far the most common type. Most persons over age 60 have some degree of lens opacity. Cigarette smoking increases the risk of cataract formation. No dietary modification has been shown to prevent age-related cataract or slow its progression.
The predominant symptom is progressive blurring of vision. Glare, especially in bright light or when driving at night; change of focusing, particularly development of nearsightedness; and monocular double vision may also occur.
Even in its early stages, a cataract can be seen through a dilated pupil with an ophthalmoscope or slit lamp. As the cataract matures, the retina will become increasingly more difficult to visualize, until finally the fundus reflection is absent and the pupil is white.
In adults functional visual impairment is the prime criterion for surgery. The cataract is usually removed by one of the techniques in which the posterior lens capsule remains (extracapsular), thus providing support for a prosthetic intraocular lens. Laser treatment may be used during surgery and may be required subsequently if the posterior capsule opacifies. Ultrasonic fragmentation (phacoemulsification) of the lens nucleus and foldable intraocular lenses allow cataract surgery to be performed through a small incision without the need for sutures, thus reducing the postoperative complication rate and accelerating visual rehabilitation. Multifocal and accommodative intraocular lenses reduce the need for both distance and near vision correction. In the developing world, manual small incision surgery in which the lens nucleus is removed intact, is increasingly popular.
Management of congenital cataract is complicated by additional technical difficulties during surgery, changes in the optics of the eye with growth influencing choice of intraocular lens power, and treatment of associated amblyopia.
Cataract surgery is cost-effective in improving survival and quality of life. In the developed world, it improves visual acuity in 95% of cases. In the other 5%, there is preexisting retinal damage or operative or postoperative complications. In less developed areas overall, the outcome is less good, in part due to uncorrected refractive error postoperatively. Treatment with an alpha-1-antagonist, such as tamsulosin or alfuzosin for benign prostatic hyperplasia or risperidone or paliperidone for psychiatric disease, increases the risk of complications during surgery (floppy iris syndrome) and in the early postoperative period. Nasolacrimal duct obstruction increases the risk of intraocular infection (endophthalmitis).
When to Refer
Patients with cataracts should be referred to an ophthalmologist when their visual impairment adversely affects their everyday activities.
American Academy of Ophthalmology Cataract and Anterior Segment Panel. Preferred Practice Panel® Guidelines. Cataract in the adult eye. San Francisco, CA: American Academy of Ophthalmology; 2011. http://one.aao.org/preferred-practice-pattern/cataract-in-adult-eye-ppp--october-2011
American Academy of Ophthalmology Cataract and Anterior Segment Panel. Preferred Practice Panel® Guidelines – Summary Benchmark. Cataract in the adult eye. San Francisco, CA: American Academy of Ophthalmology;2013. http://one.aao.org/summary-benchmark-detail/cataract-in-adult-eye-summary-benchmark--october-2
Eichenbaum JW. Geriatric vision loss due to cataracts, macular degeneration, and glaucoma. Mt Sinai J Med. 2012 Mar–Apr;79(2):276–94. [PMID: 22499498]
Kam JK et al. Nasolacrimal duct screening to minimise post-cataract surgery endophthalmitis. Clin Experiment Ophthalmol. 2013 Oct 3. [Epub ahead of print] [PMID: 24118663]
ESSENTIALS OF DIAGNOSIS
Rapid loss of vision in one eye possibly with “curtain” spreading across field of vision.
No pain or redness.
Detachment seen by ophthalmoscopy.
Most cases of retinal detachment are due to development of one or more peripheral retinal tears or holes or both (rhegmatogenous retinal detachment). This is usually spontaneous, related to degenerative changes in the vitreous, and generally occurs in persons over 50 years of age. Nearsightedness and cataract extraction are the two most common predisposing causes. Peripheral retinal defects may also be caused by penetrating or blunt ocular trauma.
Tractional retinal detachment occurs when there is preretinal fibrosis, such as in association with proliferative retinopathy secondary to diabetic retinopathy or retinal vein occlusion. Serous retinal detachment results from accumulation of subretinal fluid, such as in neovascular age-related macular degeneration or secondary to choroidal tumor.
Rhegmatogenous retinal detachment usually starts in the superior temporal area and spreads rapidly, causing visual field loss that starts inferiorly and expands upwards. Central vision remains intact until the macula becomes detached. On ophthalmoscopic examination, the retina is seen hanging in the vitreous like a gray cloud (Figure 7–3). One or more retinal tears or holes (or both) will usually be found on further examination.
Figure 7–3. Large preretinal hemorrhage. (Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
In traction retinal detachment, there is irregular retinal elevation with fibrosis. With serous retinal detachment, the retina is dome-shaped and the subretinal fluid may shift position with changes in posture.
Treatment of rhegmatogenous retinal detachments is directed at closing all of the retinal tears. A permanent adhesion between the neurosensory retina, the retinal pigment epithelium, and the choroid is produced in the region of the defects by laser photocoagulation to the retina or cryotherapy to the sclera. Indentation of the sclera with a silicone sponge or buckle; subretinal fluid drainage via an incision in the sclera; or injection of an expansile gas into the vitreous cavity, possibly following intraocular surgery to remove the vitreous (pars plana vitrectomy), may be required to achieve apposition of the neurosensory retina to the retinal pigment epithelium while the adhesion is developing. Certain types of uncomplicated retinal detachment may be treated by pneumatic retinopexy, in which an expansile gas is injected into the vitreous cavity followed by positioning of the patient’s head to facilitate reattachment of the retina. Once the retina is repositioned, the defects are sealed by laser photocoagulation or cryotherapy; these two methods are also used to seal retinal defects without associated detachment. Intravitreal injection of ocriplasmin (Jetrea), a serine protease, may release vitreo-macular traction to avoid the need for vitrectomy.
In complicated retinal detachments—particularly those in which fibroproliferative tissue has developed on the surface of the retina or within the vitreous cavity, ie, traction retinal detachments—retinal reattachment can be accomplished only by pars plana vitrectomy, direct manipulation of the retina, and internal tamponade of the retina with air, expansile gas, or silicone oil. (The presence of an expansile gas within the eye is a contraindication to air travel, mountaineering at high altitude, and nitrous oxide anesthesia. Such gases persist in the globe for weeks after surgery.) Treatment of serous retinal detachments is determined by the underlying cause.
About 90% of uncomplicated rhegmatogenous retinal detachments can be cured with one operation. The visual prognosis is worse if the macula is detached or if the detachment is of long duration.
When to Refer
All cases of retinal detachment must be referred urgently to an ophthalmologist, emergently if central vision is good because this indicates that the macula has not detached. During transportation the patient’s head is positioned so that the detached portion of the retina will fall back with the aid of gravity.
American Academy of Ophthalmology Retina Panel. Preferred Practice Panel® Guidelines. Posterior vitreous detachment, retinal breaks and lattice degeneration. San Francisco, CA: American Academy of Ophthalmology; 2013. http://one.aao.org/preferred-practice-pattern/posterior-vitreous-detachment-retinal-breaks-latti-5
American Academy of Ophthalmology Retina Panel. Preferred Practice Panel® Guidelines – Summary Benchmark. Idiopathic macular hole. San Francisco, CA: American Academy of Ophthalmology; 2013. http://one.aao.org/summary-benchmark-detail/idiopathic-macular-hole-summary-benchmark--october
Chang HJ et al. JAMA patient page. Retinal detachment. JAMA. 2012 Apr 4;307(13):1447. [PMID: 22474209]
Dorrepaal SJ et al. Using patient positioning to promote resorption of subretinal fluid in rhegmatogenous retinal detachment before pneumatic retinopexy. Retina. 2014 Mar;34(3):477–82. [PMID: 23903793]
Hatten B et al. Retinal detachment. Emerg Med J. 2011 Jan;28(1):83. [PMID: 20378746]
Olsen T et al. The incidence of retinal detachment after cataract surgery. Open Ophthalmol J. 2012;6:79–82. [PMID: 23002414]
Schwartz SG et al. Update on retinal detachment surgery. Curr Opin Ophthalmol. 2013 May;24(3):255–61. [PMID: 23429600]
Patients with vitreous hemorrhage complain of sudden visual loss, abrupt onset of floaters that may progressively increase in severity, or occasionally, “bleeding within the eye.” Visual acuity ranges from 20/20 (6/6) to light perception only. The eye is not inflamed, and clues to diagnosis are inability to see fundal details clearly despite the presence of a clear lens or localized collection of blood in front of the retina (Figure 7–3). Causes of vitreous hemorrhage include retinal tear (with or without detachment), diabetic or sickle cell retinopathy, retinal vein occlusion, retinal vasculitis, neovascular age-related macular degeneration, blood dyscrasia, trauma, subarachnoid hemorrhage, and severe straining.
When to Refer
All patients with suspected vitreous hemorrhage must be referred urgently to an ophthalmologist.
Schweitzer KD et al. Predicting retinal tears in posterior vitreous detachment. Can J Ophthalmol. 2011 Dec;46(6):481–5. [PMID: 22153633]
Takkar A et al. Teaching NeuroImages: Terson syndrome in cortical venous sinus thrombosis. Neurology. 2013 Aug 6;81(6):e40–1. [PMID: 23918868]
AGE-RELATED MACULAR DEGENERATION
ESSENTIALS OF DIAGNOSIS
Older age group.
Acute or chronic deterioration of central vision in one or both eyes.
Distortion or abnormal size of images.
No pain or redness.
Macular abnormalities seen by ophthalmoscopy.
In developed countries, age-related macular degeneration is the leading cause of permanent visual loss in the older population. Its prevalence increases with each decade over age 50 years (to almost 30% by age 75). Its occurrence and response to treatment are influenced by genetically determined variations in the complement pathway and in lipoprotein metabolism. Other associated factors are race (usually white), sex (slight female predominance), family history, cigarette smoking, and possibly regular aspirin use.
Age-related macular degeneration is classified into atrophic (“dry,” “geographic”) and neovascular (“wet,” “exudative”). Although both are progressive and usually bilateral, they differ in manifestations, prognosis, and management.
The precursor to age-related macular degeneration is age-related maculopathy, characterized by retinal drusen. Hard drusen appear ophthalmoscopically as discrete yellow deposits. Soft drusen are larger, paler, and less distinct. Large, confluent soft drusen are particularly associated with neovascular age-related macular degeneration.
Atrophic degeneration is characterized by gradually progressive bilateral visual loss of moderate severity due to atrophy and degeneration of the outer retina and retinal pigment epithelium. Inneovascular degeneration choroidal new vessels grow between the retinal pigment epithelium and Bruch membrane, leading to accumulation of serous fluid, hemorrhage, and fibrosis. The onset of visual loss is more rapid and more severe than in atrophic degeneration. The two eyes are frequently affected sequentially over a period of a few years. Neovascular disease accounts for about 90% of all cases of legal blindness due to age-related macular degeneration. Macular degeneration results in loss of central vision only. Peripheral fields and hence navigational vision are maintained, though these may become impaired by cataract formation for which surgery may be helpful.
No dietary modification has been shown to prevent the development of age-related maculopathy. In patients with age-related maculopathy, oral treatment with antioxidants (vitamins C and E), zinc, copper and carotenoids (lutein and zeaxanthin, rather than vitamin A [beta-carotene]) is recommended to reduce the risk of progression to advanced disease. Oral omega-3 fatty acids do not provide additional benefit. Laser retinal photocoagulation results in regression of drusen but does not reduce the risk of disease progression.
Inhibitors of vascular endothelial growth factors (VEGF), such as ranibizumab (Lucentis), pegaptanib (Macugen), bevacizumab (Avastin), and aflibercept (VEGF Trap-Eye, Eylea), reverse choroidal neovascularization, resulting in stabilization and less frequently improvement in vision in neovascular degeneration. They have to be administered directly into the vitreous, although topical and oral administration are being investigated. Initial trials involved monthly injections for 2 years but less frequent treatment may be sufficient when there is evidence of reactivation of disease. Treatment is well tolerated with minimal adverse effects, although there is a risk of intraocular complications. There is some concern about nonocular adverse effects of bevacizumab but it is more cost-effective than other VEGF inhibitors. Long-term outcome studies show that about one-third of eyes have a poor outcome even with prolonged treatment.
There is no specific treatment for atrophic degeneration, but—as with the neovascular form—patients may benefit from low vision aids.
When to Refer
Older patients developing sudden visual loss due to macular disease—particularly paracentral distortion or scotoma with preservation of central acuity—should be referred urgently to an ophthalmologist.
Age-Related Eye Disease Study 2 Research Group. Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: the Age-Related Eye Disease Study 2 (AREDS2) randomized clinical trial. JAMA. 2013 May 15;309(19):2005–15. [PMID: 23644932]
American Academy of Ophthalmology Retina Panel. Preferred Practice Panel® Guidelines – Summary Benchmark. Age-related macular degeneration. San Francisco, CA: American Academy of Ophthalmology; 2013. http://one.aao.org/summary-benchmark-detail/agerelated-macular-degeneration-summary-benchmark--october-2012
American Academy of Ophthalmology Vision Rehabilitation Committee. Preferred Practice Panel® Guidelines. Vision rehabilitation. San Francisco, CA: American Academy of Ophthalmology; 2013.http://one.aao.org/preferred-practice-pattern/vision-rehabilitation-ppp--2013
Cheung CM et al. Treatment of age-related macular degeneration. Lancet. 2013 Oct 12;382(9900):1230–2. [PMID: 23870812]
Goodman DM et al. JAMA patient page. Age-related macular degeneration. JAMA. 2012 Oct 24;308(16):1702. [PMID: 23093172]
Kolber MR et al. Vitamins for age-related macular degeneration demonstrate minimal differences. Can Fam Physician. 2013 May;59(5):503. [PMID: 23673586]
CENTRAL & BRANCH RETINAL VEIN OCCLUSIONS
ESSENTIALS OF DIAGNOSIS
Sudden monocular loss of vision.
No pain or redness.
Widespread or sectoral retinal hemorrhages.
All patients with retinal vein occlusion should be screened for diabetes, systemic hypertension, hyperlipidemia, and glaucoma. Estrogen therapy (including combined oral contraceptives), antiphospholipid syndromes, inherited thrombophilia, and hyperhomocysteinemia should be considered particularly in younger patients. Rarely, hyperviscosity syndromes, including myeloproliferative disorders, are associated with retinal vein occlusions and especially should be considered in simultaneous bilateral disease.
- Symptoms and Signs
The visual impairment in central retinal vein occlusion is commonly first noticed upon waking. Ophthalmoscopic signs include widespread retinal hemorrhages, retinal venous dilation and tortuosity, retinal cotton-wool spots, and optic disk swelling.
Branch retinal vein occlusion may present in a variety of ways. Sudden loss of vision may occur at the time of occlusion if the fovea is involved or some time afterward from vitreous hemorrhage due to retinal new vessels. More gradual visual loss may occur with development of macular edema. In acute branch retinal vein occlusion, the retinal abnormalities (hemorrhages, venous dilation and tortuosity, and cotton-wool spots) are confined to the area drained by the obstructed vein.
Check blood pressure in all patients.
- Laboratory Findings
Obtain screening studies for diabetes mellitus, hyperlipidemia, and hyperviscosity, including a serum protein electrophoresis especially to identify IgM paraproteinemia. Particularly in younger patients, consider obtaining antiphospholipid antibodies, lupus anticoagulant, tests for inherited thrombophilia, and plasma homocysteine levels.
If central retinal vein occlusion is associated with widespread retinal ischemia, manifesting as poor visual acuity (20/200 (6/60) or worse), florid retinal abnormalities, and extensive areas of capillary closure on fluorescein angiography, there is a high risk of development of neovascular (rubeotic) glaucoma, typically within the first 3 months.
Branch retinal vein occlusion may be complicated by peripheral retinal neovascularization or chronic macular edema.
Eyes at risk for neovascular glaucoma following ischemic central retinal vein occlusion can be treated by panretinal laser photocoagulation prophylactically or as soon as there is evidence of neovascularization, the latter approach necessitating frequent monitoring. Regression of iris neovascularization has been achieved with intravitreal injections of bevacizumab, an inhibitor of VEGF. In branch retinal vein occlusion complicated by retinal neovascularization, the ischemic retina should be laser photocoagulated.
Intravitreal injection of a VEGF inhibitor, such as ranibizumab (Lucentis), pegaptanib (Macugen), bevacizumab (Avastin), or aflibercept (VEGF Trap-Eye, Eylea), is beneficial in chronic macular edema due to either branch or nonischemic central retinal vein occlusion. Intravitreal triamcinolone improves vision in chronic macular edema due to nonischemic central retinal vein occlusion, whereas an intravitreal implant containing dexamethasone is beneficial in both central and branch retinal vein occlusion. Retinal laser photocoagulation may be indicated in chronic macular edema due to branch but not central retinal vein occlusion.
In central retinal vein occlusion, severity of visual loss initially is a good guide to visual outcome. Initial visual acuity of 20/60 (6/18) or better indicates a good prognosis. Visual prognosis is poor for eyes with neovascular glaucoma.
Visual outcome in branch retinal vein occlusion is determined by the severity of macular damage from hemorrhage, ischemia, or edema.
When to Refer
All patients with retinal vein occlusion should be referred urgently to an ophthalmologist.
Kiire CA et al. Managing retinal vein occlusion. BMJ. 2012 Feb 22;344:e499. [PMID: 22362114]
Macdonald D. The ABCs of RVO: A review of retinal venous occlusion. Clin Exp Optom. 2013 Nov 20. [Epub ahead of print] [PMID: 24256639]
Scott IU. Management of macular edema associated with retinal vein occlusion. Arch Ophthalmol. 2012 Oct 1;130(10):1314–6. [PMID: 23044946]
Shirodkhar AL et al. Management of branch retinal vein occlusion. Br J Hosp Med (Lond). 2012 Jan;73(1):20–3. [PMID: 22241405]
CENTRAL & BRANCH RETINAL ARTERY OCCLUSIONS
ESSENTIALS OF DIAGNOSIS
Sudden monocular loss of vision.
No pain or redness.
Widespread or sectoral retinal pallid swelling.
In patients 50 years of age or older with central retinal artery occlusion, giant cell arteritis must be considered (see Ischemic Optic Neuropathy and Chapter 20). Otherwise, even if no retinal emboli are identified on ophthalmoscopy, urgent investigation for carotid and cardiac sources of emboli must be undertaken in central and particularly in branch retinal artery occlusion, so that timely treatment can be given to reduce the risk of stroke (see Chapters 12, 14, and 24). Diabetes mellitus, hyperlipidemia, and systemic hypertension should be considered as etiologic factors in patients with retinal artery occlusion. Migraine, oral contraceptives, systemic vasculitis, congenital or acquired thrombophilia, and hyperhomocysteinemia should be considered, particularly in young patients. Internal carotid artery dissection should be considered when there is neck pain or a recent history of neck trauma. Multiple branch retinal artery occlusions, which may be asymptomatic, along with encephalopathy and hearing loss are the characteristic features of Susac syndrome.
- Symptoms and Signs
Central retinal artery occlusion presents as sudden profound monocular visual loss. Visual acuity is usually reduced to counting fingers or worse, and visual field is restricted to an island of vision in the temporal field. Ophthalmoscopy reveals pallid swelling of the retina with a cherry-red spot at the fovea (Figure 7–4). The retinal arteries are attenuated, and “box-car” segmentation of blood in the veins may be seen. Occasionally, emboli are seen in the central retinal artery or its branches. The retinal swelling subsides over a period of 4–6 weeks, leaving a pale optic disk and attenuated arterioles.
Figure 7–4. Acute central retinal artery occlusion with cherry-red spot and preserved retina adjacent to the optic disk due to cilioretinal artery supply. (From Esther Posner. Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
Branch retinal artery occlusion may also present with sudden loss of vision if the fovea is involved, but more commonly sudden loss of visual field is the presenting complaint. Fundal signs of retinal swelling and adjacent cotton-wool spots are limited to the area of retina supplied by the occluded artery.
Identify risk factors for cardiac source of emboli including arrhythmia, particularly atrial fibrillation, and cardiac valvular disease, and check the blood pressure. Clinical features of giant cell arteritis include age 50 years or older, jaw claudication (which is very specific), headache, scalp tenderness, general malaise, weight loss, symptoms of polymyalgia rheumatica, and tenderness, thickening, or absence of pulse of the superficial temporal arteries. Table 20–12 lists the clinical manifestations of vasculitis.
- Laboratory Findings
Erythrocyte sedimentation rate and C-reactive protein are usually markedly elevated in giant cell arteritis but one or both may be normal. Consider screening for other types of vasculitis (see Table 20–13). Screen for diabetes mellitus and hyperlipidemia in all patients. Particularly in younger patients, consider testing for antiphospholipid antibodies, lupus anticoagulant, inherited thrombophilia, and elevated plasma homocysteine.
To identify carotid and cardiac sources of emboli, obtain duplex ultrasonography of the carotid arteries, ECG, and echocardiography, with transesophageal studies (if necessary). When indicated, obtain CT or MR studies for internal carotid artery dissection.
If the patient is seen within a few hours after onset, emergency treatment—including laying the patient flat, ocular massage, high concentrations of inhaled oxygen, intravenous acetazolamide, and anterior chamber paracentesis—may influence the visual outcome. Studies of early thrombolysis, particularly by local intra-arterial injection but also intravenously, have shown good results in central retinal artery occlusion not due to giant cell arteritis but the former method has a high incidence of adverse effects and may be difficult to accomplish within the required time.
In giant cell arteritis there is risk—highest in the first few days—of involvement of the other eye. When the diagnosis is suspected, high-dose corticosteroids (oral prednisolone 1–1.5 mg/kg/d, if necessary preceded by intravenous hydrocortisone 250–500 mg immediately or, especially in patients with bilateral visual loss, methylprednisolone 0.5–1 g/d for 1–3 days) must be instituted immediately, possibly together with low-dose aspirin (~81 mg/d orally). The patient must be monitored closely to ensure that treatment is adequate. A temporal artery biopsy should be performed promptly, and if necessary, assistance should be sought from a rheumatologist.
Patients with embolic retinal artery occlusion and 70–99% ipsilateral carotid artery stenosis and possibly those with 50–69% stenosis should be considered for carotid endarterectomy or possibly angioplasty with stenting to be performed within 2 weeks (see Chapters 12 and 24). Retinal embolization due to cardiac disease such as atrial fibrillation or a hypercoagulable state usually requires anticoagulation.
When to Refer
- Patients with central retinal artery occlusion should be referred emergently to an ophthalmologist.
- Patients with branch retinal artery occlusion should be referred urgently.
When to Admit
Patients with visual loss due to giant cell arteritis may require emergency admission for high-dose corticosteroid therapy and close monitoring to ensure that treatment is adequate.
Cugati S et al. Treatment options for central retinal artery occlusion. Curr Treat Options Neurol. 2013 Feb;15(1):63–77. [PMID: 23070637]
Kennedy S. Polymyalgia rheumatica and giant cell arteritis: an in-depth look at diagnosis and treatment. J Am Acad Nurse Pract. 2012 May;24(5):277–85. [PMID: 22551331]
Salvarani C et al. Clinical features of polymyalgia rheumatica and giant cell arteritis. Nat Rev Rheumatol. 2012 Sep;8(9):509–21. [PMID: 22825731]
Varma DD et al. A review of central retinal artery occlusion: clinical presentation and management. Eye (Lond). 2013 Jun;27(6):688–97. [PMID: 23470793]
TRANSIENT MONOCULAR VISUAL LOSS
ESSENTIALS OF DIAGNOSIS
Monocular loss of vision usually lasting a few minutes with complete recovery.
Transient monocular visual loss (“ocular transient ischemic attack [TIA]”) is usually caused by a retinal embolus from ipsilateral carotid disease or the heart. The visual loss is characteristically described as a curtain passing vertically across the visual field with complete monocular visual loss lasting a few minutes and a similar curtain effect as the episode passes (amaurosis fugax; also called “fleeting blindness”). An embolus is rarely seen on ophthalmoscopy. Other causes of transient, often recurrent, visual loss due to ocular ischemia are giant cell arteritis, hypercoagulable state (such as antiphospholipid syndrome), hyperviscosity, and severe occlusive carotid disease; in the last case, the visual loss characteristically occurs on exposure to bright light. More transient visual loss, lasting only a few seconds to 1 minute, usually recurrent, and affecting one or both eyes, occurs in patients with optic disk swelling, for example in those with raised intracranial pressure. In young patients, there is a benign form of transient recurrent visual loss that has been ascribed to choroidal or retinal vascular spasm.
In most cases, clinical assessment and investigations are much the same as for retinal artery occlusion (see above) with greater emphasis on identifying a source of emboli. Optic disk swelling requires different investigations (see below).
All patients with possible embolic transient visual loss should be treated immediately with oral aspirin (at least 81 mg daily), or another antiplatelet drug, until the cause has been determined. Affected patients with 70–99% (and possibly those with 50–69%) ipsilateral carotid artery stenosis should be considered for urgent carotid endarterectomy or possibly angioplasty with stenting (see Chapters 12 and24). In all patients, vascular risk factors (eg, hypertension) need to be controlled. Retinal embolization due to a cardiac disease, such as atrial fibrillation, or a hypercoagulable state usually requires anticoagulation. In younger patients with the benign variant of transient monocular blindness, calcium channel blockers, such as slow-release nifedipine, 60 mg/d, may be effective.
When to Refer
In all cases of episodic visual loss, early ophthalmologic consultation is advisable.
When to Admit
Hospital admission is advisable in embolic transient visual loss if there have been two or more episodes in the preceding week (“crescendo TIA”) or the underlying cause is cardiac or a hypercoagulable state.
Barbetta I et al. Outcomes of urgent carotid endarterectomy for stable and unstable acute neurologic deficits. J Vasc Surg. 2014 Feb;59(2):440–6. [PMID: 24246539]
Carmo GA et al. Carotid stenosis management: a review for the internist. Intern Emerg Med. 2014 Mar;9(2):133–42. [PMID: 24057347]
Petzold A et al. Patterns of non-embolic transient monocular visual field loss. J Neurol. 2013 Jul;260(7):1889–900. [PMID: 23564298]
Ritter JC et al. Carotid endarterectomy: where do we stand at present? Curr Opin Cardiol. 2013 Nov;28(6):619–24. [PMID: 24100648]
Ritter JC et al. The current management of carotid atherosclerotic disease: who, when and how? Interact Cardiovasc Thorac Surg. 2013 Mar;16(3):339–46. [PMID: 23197661]
Simmons BB et al. Transient ischemic attack: part I. Diagnosis and evaluation. Am Fam Physician. 2012 Sep 15;86(6):521–6. [PMID: 23062043]
RETINAL DISORDERS ASSOCIATED WITH SYSTEMIC DISEASES
- Diabetic Retinopathy
ESSENTIALS OF DIAGNOSIS
Present in about 35% of all diagnosed diabetic patients.
Present in about 20% of type 2 diabetic patients at diagnosis.
Background retinopathy: mild retinal abnormalities without visual loss.
Maculopathy: macular edema, exudates, or ischemia.
Proliferative retinopathy: new retinal vessels.
Diabetic retinopathy is broadly classified as nonproliferative, which is subclassified as mild, moderate, or severe, or proliferative, which is less common but causes more severe visual loss. Diabetic retinopathy is present in about 35% of diagnosed diabetic patients. In the United States, it affects about 4 million people; it is the leading cause of new blindness among adults aged 20–65 years; and the number of affected individuals aged 65 years or older is increasing. Worldwide, there are approximately 93 million people with diabetic retinopathy, including 28 million with vision-threatening disease. Retinopathy increases in prevalence and severity with increasing duration and poorer control of diabetes. In type 1 diabetes, retinopathy is not detectable for at least 3 years after diagnosis. In type 2 diabetes, retinopathy is present in about 20% of patients at diagnosis and may be the presenting feature.
Clinical assessment uses stereoscopic examination of the retina, retinal imaging with optical coherence tomography, and sometimes fluorescein angiography.
Nonproliferative retinopathy manifests as microaneurysms, retinal hemorrhages, venous beading, retinal edema, and hard exudates (Figure 7–5). Reduction of vision is most commonly due to diabetic macular edema, which may be focal or diffuse, but it can also be due to macular ischemia. Macular involvement is the most common cause of legal blindness in type 2 diabetes. Macular edema is associated with treatment with thiazolidinediones (glitazones).
Figure 7–5. Moderate nonproliferative diabetic retinopathy with multiple microaneurysms and hemorrhages, mild macular hard exudates, and two cotton-wool spots in the superior retina.(Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
Proliferative retinopathy is characterized by neovascularization, arising from either the optic disk or the major vascular arcades. Vitreous hemorrhage is a common sequel. Proliferation into the vitreous of blood vessels, with their associated fibrous component, may lead to tractional retinal detachment.
Visual symptoms and visual acuity are poor guides to the presence of diabetic retinopathy. Adult and adolescent patients with diabetes mellitus should undergo at least yearly screening by fundal photography, commonly with centralized screening that may involve computer detection software programs, or slit-lamp examination. (Failure to identify diabetic retinopathy by direct ophthalmoscopy is common, particularly if the pupils are not dilated.) More frequent monitoring is required in women during pregnancy and in those planning pregnancy. Patients with type 2 diabetes mellitus should be screened shortly after diagnosis.
Treatment includes optimizing blood glucose, blood pressure, renal function, and serum lipids, although such measures are probably more important in preventing the development of retinopathy than in influencing its subsequent course. Fenofibrate seems to have beneficial effects beyond reduction of serum lipids.
Macular edema and exudates, but not ischemia, may respond to laser photocoagulation; to intravitreal administration of a VEGF inhibitor (ranibizumab [Lucentis], pegaptanib [Macugen], bevacizumab [Avastin] or aflibercept [VEGF Trap-Eye, Eylea]) or corticosteroid (triamcinolone, dexamethasone implant [Ozurdex], or fluocinolone implant [Retisert, Iluvien]); to vitrectomy; or to intravitreal injection of a serine protease (ocriplasmin [Jetrea]) to release vitreo-retinal traction.
Proliferative retinopathy is usually treated by panretinal laser photocoagulation, preferably before vitreous hemorrhage or tractional detachment has occurred. Regression of neovascularization can also be achieved by intravitreal injection of a VEGF inhibitor. In patients with severe nonproliferative retinopathy, fluorescein angiography can help determine whether panretinal laser photocoagulation should be undertaken prophylactically by visualizing the extent of retinal ischemia. Vitrectomy is necessary for removal of persistent vitreous hemorrhage, to improve vision and allow panretinal laser photocoagulation for the underlying retinal neovascularization, for treatment of tractional retinal detachment involving the macula, and for management of rapidly progressive proliferative disease.
Proliferative diabetic retinopathy, especially after successful laser treatment, is not a contraindication to treatment with thrombolytic agents, aspirin, or warfarin unless there has been recent vitreous or pre-retinal hemorrhage.
When to Refer
- All diabetic patients with sudden loss of vision or retinal detachment should be referred emergently to an ophthalmologist.
- Proliferative retinopathy or macular involvement requires urgent referral to an ophthalmologist.
- Severe nonproliferative retinopathy or unexplained reduction of visual acuity requires early referral to an ophthalmologist.
American Academy of Ophthalmology Retina Panel. Preferred Practice Panel® Guidelines – Summary Benchmark. Diabetic retinopathy. San Francisco, CA: American Academy of Ophthalmology; 2013.http://one.aao.org/summary-benchmark-detail/diabetic-retinopathy-summary-benchmark--october-20
Antonetti DA et al. Diabetic retinopathy. N Engl J Med. 2012 Mar 29;366(13):1227–39. [PMID: 22455417]
Bressler NM et al. Panretinal photocoagulation for proliferative diabetic retinopathy. N Engl J Med. 2011 Oct 20;365(16):1520–6. [PMID: 22010918]
Errera MH et al. Pregnancy-associated retinal diseases and their management. Surv Ophthalmol. 2013 Mar–Apr;58(2):127–42. [PMID: 23410822]
Guigui S et al. Screening for diabetic retinopathy: review of current methods. Hosp Pract (Minneap). 2012 Apr;40(2):64–72. [PMID: 22615080]
Kiire CA et al. Medical management for the prevention and treatment of diabetic macular edema. Surv Ophthalmol. 2013 Sep–Oct;58(5):459–65. [PMID: 23969020]
- Hypertensive Retinochoroidopathy
Systemic hypertension affects both the retinal and choroidal circulations. The clinical manifestations vary according to the degree and rapidity of rise in blood pressure and the underlying state of the ocular circulation. The most florid ocular changes occur in young patients with abrupt elevations of blood pressure, such as may occur in pheochromocytoma, malignant hypertension, or preeclampsia-eclampsia. Hypertensive retinopathy can be a surrogate marker for current and future nonocular end-organ damage.
Chronic hypertension accelerates the development of atherosclerosis. The retinal arterioles become more tortuous and narrow and develop abnormal light reflexes (“silver-wiring” and “copper-wiring”). There is increased venous compression at the retinal arteriovenous crossings (“arteriovenous nicking”), an important factor predisposing to branch retinal vein occlusions. Flame-shaped hemorrhages occur in the nerve fiber layer of the retina.
Acute elevations of blood pressure result in loss of autoregulation in the retinal circulation, leading to the breakdown of endothelial integrity and occlusion of precapillary arterioles and capillaries. These pathologic changes are manifested as cotton-wool spots, retinal hemorrhages, retinal edema, and retinal exudates, often in a stellate appearance at the macula (Figure 7–6). In the choroid, vasoconstriction and ischemia result in serous retinal detachments and retinal pigment epithelial infarcts that later develop into pigmented lesions that may be focal, linear, or wedge-shaped. The abnormalities in the choroidal circulation may also affect the optic nerve head, producing ischemic optic neuropathy with optic disk swelling. Fundal abnormalities are the hallmark of hypertensive crisis with retinopathy (previously known as malignant hypertension) that requires emergency treatment. Marked fundal abnormalities are likely to be associated with permanent retinal, choroidal, or optic nerve damage. Precipitous reduction of blood pressure may exacerbate such damage.
Figure 7–6. Accelerated hypertension in a young woman manifesting as marked optic disk edema, macular star of hard exudates, serous retinal detachment, and retinal hemorrhages and cotton-wool spots. (Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
Bhargava M et al. How does hypertension affect your eyes? J Hum Hypertens. 2012 Feb;26(2):71–83. [PMID: 21509040]
Chatziralli IP et al. The value of fundoscopy in general practice. Open Ophthalmol J. 2012;6:4–5. [PMID: 22435081]
Errera MH et al. Pregnancy-associated retinal diseases and their management. Surv Ophthalmol. 2013 Mar–Apr;58(2):127–42. [PMID: 23410822]
- Blood Dyscrasias
Severe thrombocytopenia or anemia may result in various types of retinal or choroidal hemorrhages, including white centered retinal hemorrhages (Roth spots) that occur in leukemia and many other situations besides bacterial endocarditis. Involvement of the macula may result in permanent visual loss.
Sickle cell retinopathy is particularly common in hemoglobin SC disease but may also occur with other hemoglobin S variants. Manifestations include “salmon-patch” preretinal/intraretinal hemorrhages, “black sunbursts” resulting from intraretinal hemorrhage, and new vessels. Severe visual loss is rare. Retinal laser photocoagulation reduces the frequency of vitreous hemorrhage from new vessels. Surgery is occasionally needed for persistent vitreous hemorrhage or tractional retinal detachment.
Charles KS et al. Ophthalmic manifestations of haematological disorders. West Indian Med J. 2013 Jan;62(1):99–103. [PMID: 24171339]
- HIV Infection/AIDS
HIV retinopathy, the most common ophthalmic abnormality in HIV infection, manifests clinically as cotton-wool spots, retinal hemorrhages, and microaneurysms but may also cause reduced contrast sensitivity, and retinal nerve fiber layer and outer retinal damage.
CMV retinitis has become less common with the availability of highly active antiretroviral therapy (HAART) but continues to be prevalent where resources are limited. It usually occurs when CD4 counts are below 50/mcL (or 0.05 × 109/L) and is characterized by progressively enlarging yellowish-white patches of retinal opacification, accompanied by retinal hemorrhages and usually beginning adjacent to the major retinal vascular arcades. Patients are often asymptomatic until there is involvement of the fovea or optic nerve, or until retinal detachment develops.
Choices for initial therapy are (1) valganciclovir 900 mg orally twice daily for 3 weeks; (2) ganciclovir 5 mg/kg intravenously twice a day, foscarnet 60 mg/kg intravenously three times a day, or cidofovir 5 mg/kg intravenously once weekly, for 2–3 weeks; or (3) local administration, using either intravitreal injection of ganciclovir or foscarnet, or the sustained-release ganciclovir intravitreal implant. All available agents are virostatic. Maintenance therapy can be achieved with lower-dose therapy (oral valganciclovir 900 mg once daily, intravenous ganciclovir 5 mg/kg/d, intravenous foscarnet 90 mg/kg/d, or intravenous cidofovir 5 mg/kg once every 2 weeks) or with intravitreal therapy. Systemic therapy has a greater risk of nonocular adverse effects but reduces mortality, incidence of nonocular CMV disease, and incidence of retinitis in the fellow eye and avoids intraocular complications of intravitreal administration. Pharmacologic prophylaxis against CMV retinitis in patients with low CD4 counts or high CMV burdens has not been found to be worthwhile.
In all patients with CMV retinitis, HAART needs to be instituted or adjusted. This may lead to the immune reconstitution inflammatory syndrome (IRIS), of which the immune recovery uveitis may lead to visual loss, predominantly due to cystoid macular edema. If the CD4 count is maintained above 100/mcL (0.1 × 109/L), it may be possible to discontinue maintenance anti-CMV therapy.
Other ophthalmic manifestations of opportunistic infections occurring in AIDS patients include herpes simplex retinitis, which usually manifests as acute retinal necrosis; toxoplasmic and candidal chorioretinitis possibly progressing to endophthalmitis; herpes zoster ophthalmicus and herpes zoster retinitis, which can manifest as acute retinal necrosis or progressive outer retinal necrosis; and various entities due to syphilis, tuberculosis, or cryptococcosis. Kaposi sarcoma of the conjunctiva (see Chapter 31) and orbital lymphoma may also be seen on rare occasions.
Carmichael A. Cytomegalovirus and the eye. Eye (Lond). 2012 Feb;26(2):237–40. [PMID: 22173076]
Gangaputra S et al. Non-cytomegalovirus ocular opportunistic infections in patients with AIDS. Am J Ophthalmol. 2013 Feb;155(2):206–12. [PMID: 23068916]
Jabs DA et al. Comparison of treatment regimens for cytomegalovirus retinitis in patients with AIDS in the era of highly active antiretroviral therapy. Ophthalmology. 2013 Jun;120(6):1262–70. [PMID: 23419804]
Sugar EA et al. Incidence of cytomegalovirus retinitis in the era of highly active antiretroviral therapy. Am J Ophthalmol. 2012 Jun;153(6):1016–24.e5. [PMID: 22310076]
Wong RW et al. Emerging concepts in the management of acute retinal necrosis. Br J Ophthalmol. 2013 May;97(5):545–52. [PMID: 23235944]
ISCHEMIC OPTIC NEUROPATHY
ESSENTIALS OF DIAGNOSIS
Sudden painless visual loss with signs of optic nerve dysfunction.
Optic disk swelling in anterior ischemic optic neuropathy.
Anterior ischemic optic neuropathy—due to inadequate perfusion of the posterior ciliary arteries that supply the anterior portion of the optic nerve—produces sudden visual loss, usually with an altitudinal field defect, and optic disk swelling. In older patients it may be caused by giant cell arteritis (arteritic anterior ischemic optic neuropathy). The predominant factor predisposing to nonarteritic anterior ischemic optic neuropathy, which subsequently affects the fellow eye in up to 25% of cases, is a congenitally crowded optic disk. Other causative factors include systemic hypertension, diabetes mellitus, hyperlipidemia, systemic vasculitis, inherited or acquired thrombophilia, and possibly ingestion of phosphodiesterase type 5 inhibitors, interferon-alpha therapy, and obstructive sleep apnea. Diabetic papillopathy is a cause of chronic (possibly ischemic) optic disk swelling that generally has a better visual outcome. Rarely, an optic neuropathy that can be difficult to differentiate from nonarteritic anterior optic neuropathy, but typically affecting both eyes simultaneously and having a more chronic course, develops in patients taking amiodarone.
Ischemic optic neuropathy, usually involving the retrobulbar optic nerve and thus not causing any optic disk swelling (posterior ischemic optic neuropathy), may occur after severe blood loss or nonocular surgery, particularly prolonged lumbar spine surgery in the prone position, or in association with dialysis. In both situations there may be several contributory factors.
Arteritic anterior ischemic optic neuropathy necessitates emergency high-dose systemic corticosteroid treatment to prevent visual loss in the other eye. (See Central & Branch Retinal Artery Occlusions, above and Polymyalgia Rheumatica & Giant Cell Arteritis, Chapter 20.) Similar treatment is required in anterior ischemic optic neuropathy due to systemic vaculitis, which may also be classified as arteritic anterior ischemic optic neuropathy. It is uncertain whether systemic or intravitreal corticosteroid therapy influences the outcome in nonarteritic anterior ischemic optic neuropathy or whether oral low-dose (˜81 mg daily) aspirin reduces the risk of fellow eye involvement. In ischemic optic neuropathy after nonocular surgery, marked anemia should be treated by blood transfusion.
When to Refer
Patients with ischemic optic neuropathy should be referred urgently to an ophthalmologist.
When to Admit
Patients with ischemic optic neuropathy due to giant cell arteritis may require emergency admission for high-dose corticosteroid therapy and close monitoring to ensure that treatment is adequate.
Hayreh SS. Ischemic optic neuropathies—where are we now? Graefes Arch Clin Exp Ophthalmol. 2013 Aug;251(8):1873–84. [PMID: 23821118]
Kitaba A et al. Perioperative visual loss after nonocular surgery. J Anesth. 2013 Dec;27(6):919–26. [PMID: 23775280]
Passman RS et al. Amiodarone-associated optic neuropathy: a critical review. Am J Med. 2012 May;125(5):447–53. [PMID: 22385784]
Postoperative Visual Loss Study Group. Risk factors associated with ischemic optic neuropathy after spinal fusion surgery. Anesthesiology. 2012 Jan;116(1):15–24. [PMID: 22185873]
Warner MA. Cracking open the door on perioperative visual loss. Anesthesiology. 2012 Jan;116(1):1–2. [PMID: 22185869]
ESSENTIALS OF DIAGNOSIS
Subacute unilateral visual loss with signs of optic nerve dysfunction.
Pain exacerbated by eye movements.
Optic disk usually normal in acute stage but subsequently develops pallor.
Inflammatory optic neuropathy (optic neuritis) is strongly associated with demyelinating disease, particularly multiple sclerosis but also acute disseminated encephalomyelitis. It also occurs in sarcoidosis; as a component of neuromyelitis optica (Devic syndrome), which is associated with serum antibodies to aquaporin-4; particularly in children following viral infection; related to infection with varicella zoster virus; with various autoimmune disorders, particularly systemic lupus erythematosus; related to treatment with biologics; and by spread of inflammation from the meninges, orbital tissues, or paranasal sinuses.
Optic neuritis in demyelinating disease is characterized by unilateral loss of vision that usually develops over a few days. Vision ranges from 20/30 (6/9) to no perception of light. Commonly there is pain behind the eye, particularly on eye movements. Field loss is usually central. There is particular loss of color vision and a relative afferent pupillary defect. In about two-thirds of cases, the optic nerve isnormal during the acute stage (retrobulbar optic neuritis). In the remainder, the optic disk is swollen (papillitis) with occasional flame-shaped peripapillary hemorrhages. Visual acuity usually improves within 2–3 weeks and returns to 20/40 (6/12) or better in 95% of previously unaffected eyes. Optic atrophy subsequently develops if there has been destruction of sufficient optic nerve fibers. Any patient with presumed demyelinating optic neuritis in which visual recovery does not occur or there are other atypical features, including continuing deterioration of vision or persisting pain after 2 weeks, should undergo further investigation, including CT or MRI of the head and orbits to exclude a lesion compressing the optic nerve.
In acute demyelinating optic neuritis, intravenous methylprednisolone (1 g daily for 3 days followed by a tapering course of oral prednisolone) has been shown to accelerate visual recovery, although in clinical practice, the oral taper is not often prescribed and oral methylprednisolone may be used. Use in an individual patient is determined by the degree of visual loss, the state of the fellow eye, and the patient’s visual requirements.
Optic neuritis due to sarcoidosis, neuromyelitis optica, herpes zoster, or systemic lupus erythematosus generally has a poorer prognosis, requires more prolonged corticosteroid therapy, may require plasma exchange in neuromyelitis optica, and may necessitate long-term immunosuppression.
Among patients with a first episode of clinically isolated optic neuritis, multiple sclerosis will develop in 50% within 15 years but the visual and neurologic prognosis is good. The major risk factors are female sex and multiple white matter lesions on brain MRI. Various disease-modifying drugs including interferon (Avonex, Rebif, Betaseron, Extavia), glatiramer acetate (Copaxone), mitoxantrone (Novantrone), natazilumab (Tysabri), and fingolimod (Gilenya) are available, and others such as teriflunomide, BG-12 (dimethyl fumarate), laquinimod, and alemtuzumab are available, to reduce the risk of further neurologic episodes and potentially the accumulation of disability but each has its own range of adverse effects that in some instances are life-threatening. Fingolimod is associated with macular edema.
When to Refer
All patients with optic neuritis should be referred urgently for ophthalmologic or neurologic assessment.
American Academy of Ophthalmology Preferred Practice Pattern® Clinical Question. Corticosteroids for optic neuritis treatment. San Francisco, CA: American Academy of Ophthalmology 2013.http://one.aao.org/clinical-questions/corticosteroids-optic-neuritis-treatment--2013
Hoorbakht H et al. Optic neuritis, its differential diagnosis and management. Open Ophthalmol J. 2012;6:65–72. [PMID: 22888383]
Jeffery DR. Recent advances in treating multiple sclerosis: efficacy, risks and place in therapy. Ther Adv Chronic Dis. 2013 Jan;4(1):45–51. [PMID: 23342246]
Morrow MJ et al. Neuromyelitis optica. J Neuroophthalmol. 2012 Jun;32(2):154–66. [PMID: 22617743]
Perumal J et al. Emerging disease-modifying therapies in multiple sclerosis. Curr Treat Options Neurol. 2012 Jun;14(3):256–63. [PMID: 22426573]
Trebst C et al. Update on the diagnosis and treatment of neuromyelitis optica: recommendations of the Neuromyelitis Optica Study Group (NEMOS). J Neurol. 2014 Jan;26(1):1–16. [PMID: 24272588]
OPTIC DISK SWELLING
Optic disk swelling may result from intraocular disease, orbital and optic nerve lesions, severe hypertensive retinochoroidopathy, or raised intracranial pressure, the last necessitating urgent imaging to exclude an intracranial mass or cerebral venous sinus occlusion but potentially being caused by numerous conditions. Intraocular causes include central retinal vein occlusion, posterior uveitis, and posterior scleritis. Optic nerve lesions causing disk swelling include anterior ischemic optic neuropathy; optic neuritis; optic disk drusen; optic nerve sheath meningioma; and infiltration by sarcoidosis, leukemia, or lymphoma. Any orbital lesion causing nerve compression may produce disk swelling.
Papilledema (optic disk swelling due to raised intracranial pressure) is usually bilateral and most commonly produces enlargement of the blind spot without loss of acuity. Chronic papilledema, as in idiopathic intracranial hypertension and cerebral venous sinus occlusion, or severe acute papilledema may be associated with visual field loss and occasionally with profound loss of acuity. All patients with chronic papilledema must be monitored carefully—especially their visual fields—and cerebrospinal fluid shunt or optic nerve sheath fenestration should be considered in those with progressive visual failure not controlled by medical therapy (weight loss where appropriate and acetazolamide).
Optic disk drusen and congenitally crowded optic disks, which are associated with farsightedness, cause optic disk elevation that may be mistaken for swelling (pseudo-papilledema). Exposed optic disk drusen may be obvious clinically or can be demonstrated by their autofluorescence. Buried drusen are best detected by orbital ultrasound or CT scanning. Other family members may be similarly affected.
Biousse V. Idiopathic intracranial hypertension: diagnosis, monitoring and treatment. Rev Neurol (Paris). 2012 Oct;168(10):673–83. [PMID: 22981270]
Biousse V et al. Update on the pathophysiology and management of idiopathic intracranial hypertension. J Neurol Neurosurg Psychiatry. 2012 May;83(5):488–94. [PMID: 22423118]
Sergott RC. Headaches associated with papilledema. Curr Pain Headache Rep. 2012 Aug;16(4):354–8. [PMID: 22669513]
OCULAR MOTOR PALSIES
In complete third nerve paralysis, there is ptosis with a divergent and slightly depressed eye. Extraocular movements are restricted in all directions except laterally (preserved lateral rectus function). Intact fourth nerve (superior oblique) function is detected by the presence of inward rotation on attempted depression of the eye. Pupillary involvement (relatively dilated pupil that does not constrict normally to light) is an important sign differentiating “surgical,” including traumatic, from “medical” causes of isolated third nerve palsy. Compressive lesions of the third nerve—eg, aneurysm of the posterior communicating artery and uncal herniation due to a supratentorial mass lesion—characteristically have pupillary involvement. Patients with painful acute isolated third nerve palsy and pupillary involvement should be assumed to have a posterior communicating artery aneurysm until this has been excluded. Pituitary apoplexy is a rarer cause. Medical causes of isolated third nerve palsy include diabetes mellitus, hypertension, giant cell arteritis, and herpes zoster.
Fourth nerve paralysis causes upward deviation of the eye with failure of depression on adduction. In acquired cases, there is vertical and torsional diplopia that are most apparent on looking down. Trauma is a major cause of acquired—particularly bilateral—fourth nerve palsy, but posterior fossa tumor and medical causes such as in third nerve palsies should also be considered. Similar clinical features are seen in congenital cases due to developmental anomaly of the nerve, muscle or tendon.
Sixth nerve paralysis causes convergent squint in the primary position with failure of abduction of the affected eye, producing horizontal diplopia that increases on gaze to the affected side and on looking into the distance. It is an important sign of raised intracranial pressure. Sixth nerve palsy may also be due to trauma, neoplasms, brainstem lesions, or medical causes such as in third nerve palsy.
An intracranial or intraorbital mass lesion should be considered in any patient with an isolated ocular motor palsy. In patients with isolated ocular motor nerve palsies presumed to be due to medical causes, brain MRI is generally only necessary if recovery has not begun within 3 months, although some authors suggest that it should be undertaken in all cases.
Ocular motor nerve palsies occurring in association with other neurologic signs may be due to lesions in the brainstem, cavernous sinus, or orbit. Lesions around the cavernous sinus involve the upper divisions of the trigeminal nerve, the ocular motor nerves, and occasionally the optic chiasm. Orbital apex lesions involve the optic nerve and the ocular motor nerves.
Myasthenia gravis and Graves ophthalmopathy (thyroid eye disease) should also be considered in the differential diagnosis of disordered extraocular movements.
When to Refer
- Any patient with recent onset isolated third nerve palsy, particularly if there is pupillary involvement or pain, must be referred emergently for neurologic assessment and CT, MR, or catheter angiography for intracranial aneurysm.
- All patients with recent onset double vision should be referred urgently to an ophthalmologist or neurologist, particularly if there is multiple cranial nerve dysfunction or other neurologic abnormalities.
When to Admit
Patients with double vision due to giant cell arteritis may require emergency admission for high-dose corticosteroid therapy and close monitoring to ensure that treatment is adequate. (See Central & Branch Retinal Artery Occlusions and Chapter 20.)
Cordonnier M et al. Neuro-ophthalmological emergencies: which ocular signs or symptoms for which diseases? Acta Neurol Belg. 2013 Sep;113(3):215–24. [PMID: 23475430]
Grāf M et al. How to deal with diplopia. Rev Neurol (Paris). 2012 Oct;168(10):720–8. [PMID: 22986079]
Lo CP et al. Neuroimaging of isolated and non-isolated third nerve palsies. Br J Radiol. 2012 Apr;85(1012):460–7. [PMID: 22253341]
Lueck CJ. Infranuclear ocular motor disorders. Handb Clin Neurol. 2011;102:281–318. [PMID: 21601071]
Pierrot-Deseilligny C. Nuclear, internuclear, and supranuclear ocular motor disorders. Handb Clin Neurol. 2011;102:319–31. [PMID: 21601072]
Sadagopan KA et al. Managing the patient with oculomotor nerve palsy. Curr Opin Ophthalmol. 2013 Sep;24(5):438–47. [PMID: 23872817]
Tamhankar MA et al. Isolated third, fourth, and sixth cranial nerve palsies from presumed microvascular versus other causes: a prospective study. Ophthalmology. 2013 Nov;120(11):2264–9. [PMID: 23747163]
THYROID EYE DISEASE (Graves Ophthalmopathy)
Thyroid eye disease is a syndrome of clinical and orbital imaging abnormalities caused by deposition of mucopolysaccharides and infiltration with chronic inflammatory cells of the orbital tissues, particularly the extraocular muscles. It usually occurs in association with autoimmune hyperthyroidism. Clinical or laboratory evidence of thyroid dysfunction and thyroid antibodies may not be detectable at presentation or even on long-term follow-up, but their absence requires consideration of other disease entities. Radioiodine therapy, possibly indirectly due to induction of hypothyroidism, and cigarette smoking increase the severity of thyroid eye disease and ethanol injection of thyroid nodules has been reported to be followed by severe disease. Ocular myasthenia and thyroid eye disease are associated and may coexist, the presence of ptosis rather than eyelid retraction being a characteristic feature.
The primary clinical features are proptosis, lid retraction and lid lag, conjunctival chemosis and episcleral inflammation, and extraocular muscle dysfunction. Resulting symptoms are cosmetic abnormalities, surface irritation, which usually responds to artificial tears, and diplopia, which should be treated conservatively (eg, with prisms) in the active stages of the disease and only by surgery when the disease has been static for at least 6 months. The important complications are corneal exposure and optic nerve compression, both of which may lead to marked visual loss. The primary imaging features are enlargement of the extraocular muscles, usually affecting both orbits. The clinical and imaging abnormalities of thyroid eye disease may be mimicked by dural carotico-cavernous fistula.
Treatment options for optic nerve compression or severe corneal exposure are intravenous pulse methylprednisolone therapy (eg, 1 g daily for 3 days, repeated weekly for 3 weeks), oral prednisolone 80–100 mg/d, radiotherapy, or surgery (usually consisting of extensive removal of bone from the medial, inferior, and lateral walls of the orbit), either singly or in combination. The role of systemic or orbital rituximab is uncertain.
The optimal management of moderately severe thyroid eye disease without visual loss is controversial. Systemic corticosteroids and radiotherapy may be beneficial. Peribulbar corticosteroid injections have been advocated. Surgical decompression may be justified in patients with marked proptosis. Lateral tarsorrhaphy may be used for moderately severe corneal exposure. Other procedures are particularly useful for correcting lid retraction but should not be undertaken until the orbital disease is quiescent and orbital decompression or extraocular muscle surgery has been undertaken. Oral selenium seems to be beneficial in mild disease. Establishing and maintaining euthyroidism are important in all cases.
When to Refer
All patients with thyroid eye disease should be referred to an ophthalmologist, urgently if there is reduced vision.
Alhambra Expósito MR et al. Clinical efficacy of intravenous glucocorticoid treatment in Graves’ ophthalmopathy. Endocrinol Nutr. 2013 Jan;60(1):10–4. [PMID: 23177093]
Bartalena L. Diagnosis and management of Graves disease: a global overview. Nat Rev Endocrinol. 2013 Dec;9(12):724–34. [PMID: 24126481]
Dolman PJ. Evaluating Graves’ orbitopathy. Best Pract Res Clin Endocrinol Metab. 2012 Jun;26(3):229–48. [PMID: 22632361]
Hegedüs L et al. Treating the thyroid in the presence of Graves’ ophthalmopathy. Best Pract Res Clin Endocrinol Metab. 2012 Jun;26(3):313–24. [PMID: 22632368]
Menconi F et al. Spontaneous improvement of untreated mild Graves’ ophthalmopathy: the Rundle curve revisited. Thyroid. 2014 Jan;24(1):60–6. [PMID: 23980907]
Orbital cellulitis is characterized by fever, proptosis, restriction of extraocular movements, and swelling with redness of the lids. Immediate treatment with intravenous antibiotics is necessary to prevent optic nerve damage and spread of infection to the cavernous sinuses, meninges, and brain. Infection of the paranasal sinuses is the usual underlying cause; examples of infecting organisms include S pneumoniae, the incidence of which has been reduced by the administration of pneumococcal vaccine, other streptococci such as the anginosus group, H influenzae and, less commonly, S aureus. Penicillinase-resistant penicillin, such as nafcillin, is recommended, possibly together with metronidazole or clindamycin to treat anaerobic infections (Table 30–5). If trauma is the underlying cause, a cephalosporin, such as cefazolin or ceftriaxone, should be added to ensure coverage for S aureus and group A beta-hemolytic streptococci. Vancomycin or clindamycin may be required if there is concern about MRSA, which is infrequently associated with paranasal sinus infection. MRSA may cause multiple orbital abscesses and delay in the institution of vancomycin or clindamycin frequently necessitates surgery with a poor visual outcome. For patients with penicillin hypersensitivity, vancomycin, levofloxacin, and metronidazole are recommended. The response to antibiotics is usually excellent, but surgery may be required to drain the paranasal sinuses or orbital abscess. In immunocompromised patients, zygomycosis must be considered.
When to Refer
All patients with suspected orbital cellulitis must be referred emergently to an ophthalmologist.
Mathias MT et al. Atypical presentations of orbital cellulitis caused by methicillin-resistant Staphylococcus aureus. Ophthalmology. 2012 Jun;119(6):1238–43. [PMID: 22406032]
Ocular trauma, which occurs in many different circumstances and by a variety of mechanisms, is an important cause of severe visual impairment at all ages but particularly in young adult males and is the leading cause of monocular blindness in the United States. Thorough but safe clinical assessment, supplemented when necessary by imaging, is crucial to effective management.
Huang YH et al. Ocular trauma. JAMA. 2012 Aug 15;308(7):710–1. [PMID: 22893168]
Powell J et al. Surgical ophthalmologic examination. Oral Maxillofac Surg Clin North Am. 2012 Nov;24(4):557–72. [PMID: 22995153]
Scruggs D et al. Ocular injuries in trauma patients: an analysis of 28,340 trauma admissions in the 2003–2007 National Trauma Data Bank National Sample Program. J Trauma Acute Care Surg. 2012 Nov;73(5):1308–12. [PMID: 22914085]
- Conjunctival & Corneal Foreign Bodies
If a patient complains of “something in my eye” and gives a consistent history, a foreign body is usually present on the cornea or under the upper lid even though it may not be visible. Visual acuity should be tested before treatment is instituted, to assess the severity of the injury and as a basis for comparison in the event of complications.
After a local anesthetic (eg, proparacaine, 0.5%) is instilled, the eye is examined with a hand flashlight, using oblique illumination, and loupe. Corneal foreign bodies may be made more apparent by the instillation of sterile fluorescein. They are then removed with a sterile wet cotton-tipped applicator or hypodermic needle. Bacitracin-polymyxin ophthalmic ointment should be instilled. It is not necessary to patch the eye.
Steel foreign bodies usually leave a diffuse rust ring (Figure 7–7). This requires excision of the affected tissue and is best done under local anesthesia using a slit lamp. Caution: Anesthetic drops should not be given to the patient for self-administration.
Figure 7–7. Corneal rust stain from metallic foreign body (arrow). (From James J Augsburger and Zélia M Corrêa. Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
If there is no infection, a layer of corneal epithelial cells will line the crater within 24 hours. The intact corneal epithelium forms an effective barrier to infection, but once it is disturbed the cornea becomes extremely susceptible to infection. Early infection is manifested by a white necrotic area around the crater and a small amount of gray exudate.
In the case of a foreign body under the upper lid, a local anesthetic is instilled and the lid is everted by grasping the lashes gently and exerting pressure on the mid portion of the outer surface of the upper lid with an applicator. If a foreign body is present, it can easily be removed by passing a wet sterile cotton-tipped applicator across the conjunctival surface.
When to Refer
Urgent referral to an ophthalmologist should be arranged if a corneal foreign body cannot be removed or if there is suspicion of corneal infection.
- Intraocular Foreign Body
Intraocular foreign body requires emergency treatment by an ophthalmologist. Patients giving a history of “something hitting the eye”—particularly while hammering on metal or using grinding equipment—must be assessed for this possibility, especially when no corneal foreign body is seen, a corneal or scleral wound is apparent, or there is marked visual loss or media opacity. Such patients must be treated as for corneal laceration (see below) and referred without delay. Intraocular foreign bodies significantly increase the risk of intraocular infection.
When to Refer
Patients with suspected intraocular foreign body must be referred emergently to an ophthalmologist.
Faghihi H et al. Posttraumatic endophthalmitis: report No. 2. Retina. 2012 Jan;32(1):146–51. [PMID: 21775927]
- Corneal Abrasions
A patient with a corneal abrasion complains of severe pain and photophobia. There is often a history of trauma to the eye, commonly involving a fingernail, piece of paper, or contact lens. Visual acuity is recorded, and the cornea and conjunctiva are examined with a light and loupe to rule out a foreign body. If an abrasion is suspected but cannot be seen, sterile fluorescein is instilled into the conjunctival sac: the area of corneal abrasion will stain a deeper green than the surrounding cornea.
Treatment includes bacitracin-polymyxin ophthalmic ointment, mydriatic (cyclopentolate 1%), and analgesics either topical or oral nonsteroidal anti-inflammatory agents. Padding the eye is probably not helpful for small abrasions. Recurrent corneal erosion may follow corneal abrasions.
Riordan-Eva P. Ophthalmic emergencies. In: Vaughan & Asbury’s General Ophthalmology, 18th ed. Riordan-Eva P et al (editors). McGraw-Hill, 2011.
Wipperman JL et al. Evaluation and management of corneal abrasions. Am Fam Physician. 2013 Jan 15;87(2):114–20. [PMID: 23317075]
Contusion injuries of the eye and surrounding structures may cause ecchymosis (“black eye”), subconjunctival hemorrhage, edema or rupture of the cornea, hemorrhage into the anterior chamber (hyphema), rupture of the root of the iris (iridodialysis), paralysis of the pupillary sphincter, paralysis of the muscles of accommodation, cataract, dislocation of the lens, vitreous hemorrhage, retinal hemorrhage and edema (most common in the macular area), detachment of the retina, rupture of the choroid, fracture of the orbital floor (“blowout fracture”), or optic nerve injury. Many of these injuries are immediately obvious; others may not become apparent for days or weeks. The possibility of globe injury must always be considered in patients with facial injury, particularly if there is an orbital fracture. Patients with moderate to severe contusions should be seen by an ophthalmologist.
Any injury causing hyphema involves the danger of secondary hemorrhage, which may cause intractable glaucoma with permanent visual loss. The patient should be advised to rest until complete resolution has occurred. Daily ophthalmologic assessment is essential. Aspirin and any drugs inhibiting coagulation increase the risk of secondary hemorrhage and are to be avoided. Sickle cell anemia or trait adversely affects outcome.
When to Refer
Patients with moderate or severe ocular contusion should be referred to an ophthalmologist, emergently if there is hyphema.
Blice JP. Ocular injuries, triage, and management in maxillofacial trauma. Atlas Oral Maxillofac Surg Clin North Am. 2013 Mar;21(1):97–103. [PMID: 23498334]
If the lid margin is lacerated, the patient should be referred for specialized care, since permanent notching may result. Lacerations of the lower eyelid near the inner canthus often sever the lower canaliculus, for which canalicular intubation is likely to be required. Lid lacerations not involving the margin may be sutured like any skin laceration.
In lacerations of the conjunctiva, sutures are not necessary. To prevent infection, topical sulfonamide or antibiotic is used until the laceration is healed.
- Cornea or Sclera
Patients with suspected corneal or scleral lacerations must be seen promptly by an ophthalmologist (Figure 7–8). Manipulation is kept to a minimum, since pressure may result in extrusion of the intraocular contents. The eye is bandaged lightly and covered with a metal shield that rests on the orbital bones above and below. The patient should be instructed not to squeeze the eye shut and to remain still. The eye is routinely imaged by radiography, and CT scanning if necessary, to identify and localize any metallic intraocular foreign body. MRI is contraindicated because of the risk of movement of the foreign body in the magnetic field. Endophthalmitis occurs in over 5% of open globe injuries.
Figure 7–8. Corneoscleral laceration inferonasally with pupil displaced toward the laceration and iris incarcerated in wound. (From James J Augsburger and Zélia M Corrêa. Reproduced, with permission, from Riordan-Eva P, Cunningham ET Jr. Vaughan & Asbury’s General Ophthalmology, 18th ed. McGraw-Hill, 2011.)
When to Refer
Patients with suspected globe laceration must be referred emergently to an ophthalmologist.
Agrawal R et al. Pre-operative variables affecting final vision outcome with a critical review of ocular trauma classification for posterior open globe (zone III) injury. Indian J Ophthalmol. 2013 Oct;61(10):541–5. [PMID: 24212303]
Agrawal R et al. Prognostic factors for open globe injuries and correlation of ocular trauma score at a tertiary referral eye care centre in Singapore. Indian J Ophthalmol. 2013 Sep;61(9):502–6. [PMID: 24104709]
Bunting H et al. Prediction of visual outcomes after open globe injury in children: a 17-year Canadian experience. J AAPOS. 2013 Feb;17(1):43–8. [PMID: 23363881]
Nishide T et al. Preoperative factors associated with improvement in visual acuity after globe rupture treatment. Eur J Ophthalmol. 2013 Sep–Oct;23(5):718–22. [PMID: 23483506]
Patel SN et al. Diagnostic value of clinical examination and radiographic imaging in identification of intraocular foreign bodies in open globe injury. Eur J Ophthalmol. 2012 Mar–Apr;22(2):259–68. [PMID: 21607931]
ULTRAVIOLET KERATITIS (ACTINIC KERATITIS)
Ultraviolet burns of the cornea are usually caused by use of a sunlamp without eye protection, exposure to a welding arc, or exposure to the sun when skiing (“snow blindness”). There are no immediate symptoms, but about 6–12 hours later the patient complains of agonizing pain and severe photophobia. Slit-lamp examination after instillation of sterile fluorescein shows diffuse punctate staining of both corneas.
Treatment consists of binocular patching and instillation of 1–2 drops of 1% cyclopentolate (to relieve the discomfort of ciliary spasm). All patients recover within 24–48 hours without complications. Local anesthetics should not be prescribed because they delay corneal epithelial healing.
CHEMICAL CONJUNCTIVITIS & KERATITIS
Chemical burns are treated by copious irrigation of the eyes with tap water, saline solution, or buffering solution if available as soon as possible after exposure. Neutralization of an acid with an alkali or vice versa generates heat and may cause further damage. Alkali injuries are more serious and require prolonged irrigation, since alkalies are not precipitated by the proteins of the eye as are acids. It is important to remove any retained particulate matter such as is typically present in injuries involving cement and building plaster. This may require double eversion of the upper lid. The pupil should be dilated with 1% cyclopentolate, 1 drop twice a day, to relieve discomfort and prophylactic topical antibiotics should be started. In moderate to severe injuries, intensive topical corticosteroids and topical and systemic vitamin C are also necessary. Complications include mucus deficiency, scarring of the cornea and conjunctiva, symblepharon (adhesions between the tarsal and bulbar conjunctiva), tear duct obstruction, and secondary infection. It can be difficult to assess severity of chemical burns without slit-lamp examination.
Chau JP et al. A systematic review of methods of eye irrigation for adults and children with ocular chemical burns. Worldviews Evid Based Nurs. 2012 Aug;9(3):129–38. [PMID: 21649853]
Singh P et al. Ocular chemical injuries and their management. Oman J Ophthalmol. 2013 May;6(2):83–86. [PMID: 24082664]
TREATMENT OF OCULAR DISORDERS
Table 7–2 lists commonly used ophthalmic drugs and their indications and costs.
PRECAUTIONS IN MANAGEMENT OF OCULAR DISORDERS
- Use of Local Anesthetics
Unsupervised self-administration of local anesthetics is dangerous because the patient may further injure an anesthetized eye without knowing it. The drug may also interfere with the normal healing process.
- Pupillary Dilation
Dilating the pupil can very occasionally precipitate acute glaucoma if the patient has a narrow anterior chamber angle and should be undertaken with caution if the anterior chamber is obviously shallow (readily determined by oblique illumination of the anterior segment of the eye). A short-acting mydriatic such as tropicamide should be used and the patient warned to report immediately if ocular discomfort or redness develops. Angle closure is more likely to occur if pilocarpine is used to overcome pupillary dilation than if the pupil is allowed to constrict naturally.
Gracitelli CP et al. Ability of non-ophthalmologist doctors to detect eyes with occludable angles using the flashlight test. Int Ophthalmol. 2013 Oct 1. [Epub ahead of print] [PMID: 24081914]
Lavanya R et al. Risk of acute angle closure and changes in intraocular pressure after pupillary dilation in Asian subjects with narrow angles. Ophthalmology. 2012 Mar;119(3):474–80. [PMID: 22118999]
- Corticosteroid Therapy
Repeated use of local corticosteroids presents several hazards: herpes simplex (dendritic) keratitis, fungal infection, open-angle glaucoma, and cataract formation. Furthermore, perforation of the cornea may occur when corticosteroids are used for herpes simplex keratitis. Topical nonsteroidal anti-inflammatory agents are being used increasingly. The potential for causing or exacerbating systemic hypertension, diabetes mellitus, gastritis, osteoporosis, or glaucoma must always be borne in mind when systemic corticosteroids are prescribed, such as for uveitis or giant cell arteritis.
- Contaminated Eye Medications
Ophthalmic solutions are prepared with the same degree of care as fluids intended for intravenous administration, but once bottles are opened there is always a risk of contamination, particularly with solutions of tetracaine, proparacaine, fluorescein, and any preservative-free preparations. The most dangerous is fluorescein, as this solution is frequently contaminated with P aeruginosa, which can rapidly destroy the eye. Sterile fluorescein filter paper strips are recommended for use in place of fluorescein solutions.
Whether in plastic or glass containers, eye solutions should not remain in use for long periods after the bottle is opened. Four weeks after opening is an absolute maximal time to use a solution containing preservatives before discarding. Preservative-free preparations should be kept refrigerated and discarded within 1 week after opening. Single-use vials should not be reused.
If the eye has been injured accidentally or by surgical trauma, it is of the greatest importance to use freshly opened bottles of sterile medications or single-use eyedropper units.
- Toxic & Hypersensitivity Reactions to Topical Therapy
In patients receiving long-term topical therapy, local toxic or hypersensitivity reactions to the active agent or preservatives may develop, especially if there is inadequate tear secretion. Preservatives in contact lens cleaning solutions may produce similar problems. Burning and soreness are exacerbated by drop instillation or contact lens insertion; occasionally, fibrosis and scarring of the conjunctiva and cornea may occur. Preservative-free topical medication and contact lens solutions are available.
An antibiotic instilled into the eye can sensitize the patient to that drug and cause an allergic reaction upon subsequent systemic administration. Potentially fatal anaphylaxis is known to occur in up to 0.3% of patients after intravenous fluorescein for fluorescein angiography. Anaphylaxis also has been reported after topical fluorescein.
- Systemic Effects of Ocular Drugs
The systemic absorption of certain topical drugs (through the conjunctival vessels and lacrimal drainage system) must be considered when there is a systemic medical contraindication to the use of the drug. Ophthalmic solutions of the nonselective beta-blockers, eg, timolol, may worsen bradycardia, heart failure, or asthma. Phenylephrine eye drops may precipitate hypertensive crises and angina. Also to be considered are adverse interactions between systemically administered and ocular drugs. Using only 1 or 2 drops at a time and a few minutes of nasolacrimal occlusion or eyelid closure ensure maximum efficacy and decrease systemic side effects of topical agents.
ADVERSE OCULAR EFFECTS OF SYSTEMIC DRUGS
Systemically administered drugs produce a wide variety of adverse effects on the visual system. Table 7–3 lists the major examples. Routine periodic screening is recommended to exclude retinopathy in patients treated with hydroxychloroquine.
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