The Wills Eye Manual

Chapter 8. Pediatrics

8.1 Leukocoria

Definition

A white pupillary reflex (see Figure 8.1.1).

FIGURE 8.1.1 Leukocoria.

Etiology

FIGURE 8.1.2 Coats disease.

 Retinoblastoma: A malignant tumor of the retina that appears as a white, nodular mass that breaks through the internal limiting membrane into the vitreous (endophytic), as a subretinal mass lesion often underlying a serous retinal detachment (exophytic), or as a diffusely spreading lesion simulating uveitis (diffuse infiltrating). Iris neovascularization is common with large tumors. Aqueous and vitreous seeding may occur. Cataract is uncommon, and the eye is normal in size. May be bilateral, unilateral, or multifocal. Diagnosis is usually made in patients under 5 years of age, with a mean age of 18 months. A family history may be elicited in about 10%.

 Toxocariasis: A nematode infection that may appear as a localized, white, elevated granuloma in the retina or as a diffuse endophthalmitis. Associated with localized inflammation of ocular structures, vitreous traction bands and related macular dragging, traction retinal detachment, and cataract. It is rarely bilateral and is usually diagnosed between 6 months and 10 years of age but may present in adults as well. Paracentesis of the anterior chamber may reveal eosinophils; serum enzyme-linked immunosorbent assay (ELISA) test for Toxocara organisms is positive. The patient may have a history of contact with puppies or of eating dirt. Toxocariasis may also be acquired prenatally and present as a congenital infection.

 Coats disease (see Figure 8.1.2): A retinal vascular abnormality resulting in microaneurysms and macroaneurysms of the retinal vessels, usually in the inferotemporal periphery. Xanthocoria may develop secondary to an exudative, often bullous retinal detachment associated with yellow-colored, lipid-rich subretinal fluid or to extensive, yellow intraretinal and subretinal exudate. Usually develops in boys during the first decade of life; more severe cases occur in early childhood. Coats disease is rarely bilateral. No family history.

 Persistent fetal vasculature (PFV) (previously known as persistent hyperplastic primary vitreous): A developmental ocular abnormality with failure of regression of the fetal hyaloid complex, often with a fibrovascular stalk from the optic nerve to lens and anterior segment. May only present with anterior or posterior findings. It is usually associated with a small eye. Typically there is a membrane behind the lens that places inward traction on elongated ciliary processes. A cataract is noted at birth or early in life. The membrane and lens may rotate anteriorly, shallowing the anterior chamber and resulting in secondary glaucoma. Traction retinal detachment can occur. Usually unilateral. No family history or other risk factors.

 Pediatric cataract: Opacity of the lens present at birth or in first months of life; may be unilateral or bilateral. There may be a family history or an associated systemic disorder. See 8.8, Pediatric Cataract.

• Retinal astrocytoma: A sessile to slightly elevated, yellow-white retinal mass that may be calcified and is often associated with tuberous sclerosis complex and rarely neurofibromatosis. May occur on the optic nerve head (giant drusen) in patients with tuberous sclerosis.

 Retinopathy of prematurity (ROP): Predominantly occurs in premature children. Leukocoria is usually the result of a retinal detachment. See 8.2, Retinopathy of Prematurity.

 Others: Retinal detachment, retinochoroidal coloboma, familial exudative vitreoretinopathy (FEVR), myelinated nerve fibers, uveitis, toxoplasmosis, trauma, cytomegalovirus retinitis, endophthalmitis, retinal dysplasia, incontinentia pigmenti, Norrie disease, and medulloepithelioma.

Workup

1. History: Age at onset? Family history of one of the conditions mentioned? Prematurity? Contact with puppies or history of eating dirt?

2. Complete ocular examination, including a measurement of corneal diameters (look for a small eye), an examination of the iris (look for neovascularization), and an inspection of the lens (look for a cataract). A dilated fundus examination and an anterior vitreous examination are essential.

3. Any or all of the following may be helpful in diagnosis and planning treatment:

 B-scan ultrasonography (US), especially if there is no view of the fundus. This can be used to look for calcification within a suspected tumor, a persistent stalk from the optic disc to the back of the lens, or a retinal detachment.

 Intravenous fluorescein angiogram (useful for evaluation of Coats disease, ROP, retinoblastoma).

 Magnetic resonance imaging (MRI) (or computed tomography [CT]) of the orbit and brain, particularly for bilateral cases of retinoblastoma or those with a family history. Also advised in cases of advanced Coats disease. MRI is preferable for retinoblastoma to reduce radiation exposure, given risk of future malignancy.

 Serum ELISA test for Toxocara (positive at 1:8 in the vast majority of infected patients).

 Systemic evaluation by pediatrician, especially if concern for retinal astrocytic hamartoma, retinoblastoma, or cataract secondary to systemic disease.

 Anterior chamber paracentesis and serum ELISA test for evaluation of toxocariasis (serum antibody test positive at 1:8 in the vast majority of patients infected with Toxocara). See Appendix 13, Anterior Chamber Paracentesis.

NOTE: Anterior chamber paracentesis in a patient with a retinoblastoma should be avoided as it could lead to tumor cell dissemination.

4. May need examination under anesthesia (EUA) in young or uncooperative children, particularly when retinoblastoma is being considered as a diagnosis. If there is concern for inherited retinoblastoma, screening examination can be performed in the office within 1 to 2 weeks of birth. See 8.8, Pediatric Cataract, for a more specific cataract workup.

Treatment

1. Retinoblastoma: Chemoreduction, intra-arterial chemotherapy, intravitreal chemotherapy, cryotherapy, thermotherapy, laser photocoagulation, or plaque radiotherapy. These treatment modalities are typically used in combination. Enucleation is reserved for cases not amenable to the above treatment options or in advanced unilateral cases. Systemic chemotherapy is used in metastatic disease. External irradiation is rarely used as it is associated with a high incidence of secondary tumors later in life.

2. Toxocariasis:

 Steroids (topical, periocular, or systemic routes may be used, depending on the severity of the inflammation).

 Consider vitrectomy when vitreoretinal traction bands form or when the condition does not improve or worsens with medical therapy.

 Consider laser photocoagulation of the nematode if it is visible.

 Antihelminth therapy (albendazole) only warranted for systemic disease.

3. Coats disease: Fluorescein angiography-guided laser photocoagulation to leaking vessels and aneurysms and can consider intravitreal anti-VEGF agents in addition to the laser if there is posterior involvement. External drainage of the subretinal fluid may be beneficial for severe retinal detachment.

4. PFV:

 Cataract removal and retrolental stalk resection, with posterior vitrectomy depending on extent of posterior involvement.

 Treat any amblyopia, although visual outcome is often poor secondary to numerous factors such as foveal hypoplasia, anisometropia, optic nerve hypoplasia, and sensory deprivation.

5. Pediatric cataract: See 8.8, Pediatric Cataract.

6. Retinal astrocytoma: Observation.

7. ROP: See 8.2, Retinopathy of Prematurity.

Follow Up

Variable, depending on the diagnosis. If any concern for heritable disorders, consider referral to ophthalmic genetics and screening of family members.

8.2 Retinopathy of Prematurity

Risk Factors

 Prematurity, especially ≤30 weeks of gestation.

 Birth weight ≤1,500 g (3 lb, 5 oz).

 Use of supplemental oxygen, neonatal sepsis, hypoxemia, hypercarbia, failure to thrive, coexisting illness, Caucasian race, and male sex.

 Risk factors mentioned above, when present concurrently, have an additive effect on the risk for development of ROP.

Signs

Critical. Avascular peripheral retina. Demarcation line between vascular and avascular retina.

Other. Extraretinal fibrovascular proliferation, vitreous hemorrhage, retinal detachment, or leukocoria. Commonly bilateral. Association of “plus disease” in more severe cases includes engorgement and tortuosity of the vessels in the posterior pole and/or iris. Poor pupillary dilation despite mydriatic drops. In older children and adults, risk for decreased visual acuity, amblyopia, myopia, strabismus, macular dragging, lattice-like vitreoretinal degeneration, and retinal detachment.

Differential Diagnosis

 FEVR: Can appear similar to ROP, except FEVR is hereditary (although family members may be asymptomatic, and de novo mutations frequently occur) and more often asymmetric; asymptomatic family members often show peripheral retinal vascular abnormalities. There usually is no history of prematurity or oxygen therapy. See 8.3, Familial Exudative Vitreoretinopathy.

 Incontinentia pigmenti: X-linked dominant condition that usually occurs in girls. Often lethal in males. Characterized by skin changes including erythematous maculopapular lesions, vesicles, hypopigmented patches, and alopecia. Associated with eosinophilia. Central nervous system and dental abnormalities also seen.

 See 8.1, Leukocoria, for additional differential diagnoses.

Classification

Location

 Zone I: Posterior pole: Twice the disc-fovea distance, centered around the disc (poorest prognosis).

NOTE: With the nasal edge of the optic disc at one edge of the field of view with a 28D lens, the limit of zone I is at the temporal field of view.

 Zone II: From zone I to the nasal ora serrata; temporally equidistant from the disc.

NOTE: ROP should not be considered zone III until one is sure the nasal side is vascularized to the ora serrata.

• Zone III: The remaining temporal periphery.

Extent

 Number of clock hours (30-degree sectors) involved. Of note, the number of clock hours of neovascularization was important in older treatment criteria, but it is not used in the most updated treatment guidelines.

Severity

FIGURE 8.2.1 Retinopathy of prematurity: Stage 1.

FIGURE 8.2.2 Retinopathy of prematurity: Stage 3.

 Stage 1: Flat demarcation line separating the vascular posterior retina from the avascular peripheral retina (see Figure 8.2.1).

 Stage 2: Ridged demarcation line.

 Stage 3: Ridged demarcation line with fibrovascular proliferation or neovascularization extending from the ridge (see Figure 8.2.2).

 Stage 4A: Extrafoveal partial retinal detachment.

 Stage 4B: Fovea-involving partial retinal detachment.

 Stage 5: Total retinal detachment.

NOTE: Overall stage is determined by the most severe manifestation; however, it is recommended to define each stage and extent.

“Plus” Disease

At least two quadrants of engorged veins and tortuous arteries in the posterior pole; iris vascular engorgement, poor pupil dilatation, and vitreous haze with more advanced plus disease. If plus disease is present, a "+" is placed after the stage (e.g., stage 3+). If vascular dilatation and tortuosity are present but inadequate to diagnose plus disease, it is called "pre-plus" disease and noted after the stage (e.g., stage 3 with pre-plus disease). Rapidly progressing posterior ROP (usually zone I) with extensive plus disease, formerly known as "rush" disease, may progress rapidly to stage 5 ROP without passing through the other stages. This aggressive ROP may also show hemorrhages at the junction between vascular and avascular retina (see Figure 8.2.3).

FIGURE 8.2.3 Retinopathy of prematurity: Plus disease.

Type 1 ROP

Defines high-risk eyes that meet the criteria for treatment:

 Zone I, any stage with plus disease.

 Zone I, stage 3 without plus disease.

 Zone II, stage 2 or 3 with plus disease.

Type II ROP

Defines less severely advanced eyes that should be monitored closely for progression to type 1 disease:

 Zone I, stage 1 and 2 without plus disease.

 Zone II, stage 3 without plus disease.

Prethreshold and Threshold Disease

Terminology historically used as part of a classification system based on the CRYO-ROP study. Originally determined treatment criteria, but no longer used as part of standard of care.

Screening Recommendations

 Birth weight ≤1,500 g.

 Gestational age ≤30 weeks.

 Selected infants with birth weight >1,500 g or gestational age ≥31 weeks with unstable clinical course thought to be at high risk.

 Timing of first eye examination is based on postmenstrual (gestational age at birth plus chronologic age) and postnatal (chronologic since birth) age. The first eye examination should start at 31 to 32 weeks postmenstrual age or 4 weeks postnatal age, whichever is later.

NOTE: The American Academy of Pediatrics provides updated guidelines for ROP screening in premature infants. For the latest recommendations, please see their most recent policy statement.

Workup

1. Dilated retinal examination with scleral depression at 31 to 32 weeks after date of mother’s last menstrual period or 4 weeks after birth, whichever is later.

2. Can dilate with any two-agent combination from the following: phenylephrine, 1%; tropicamide, 1%; cyclopentolate, 0.2% to 0.5%. A fixed combined drop of phenylephrine 1% and cyclopentolate 0.2% is available. Consider repeating the drops in 30 to 45 minutes if the pupil is not dilated.

Treatment

FIGURE 8.2.4 Retinopathy of prematurity after laser treatment.

 Therapeutic goal is ablation of avascular peripheral retina with near-confluent spots. Laser photocoagulation is preferred over cryotherapy. Treatment should be instituted within 48 to 72 hours (see Figure 8.2.4). Use of intravitreal anti-VEGF agents (0.625 mg in 0.025 mL of solution of bevacizumab is the typical dosing) is an emerging treatment modality, especially when photocoagulation is not available or in very posterior zone 1 cases; however, the long-term effects and potential risks of these medications in preterm infants are yet to be determined.

 Type 1 ROP needs treatment.

 Type 2 ROP should be followed closely.

 For acute stages 4 and 5: Surgical repair of retinal detachment by vitrectomy.

Follow Up

 A single ocular examination is sufficient only if it unequivocally shows full retinal vascularization in both eyes.

 One week or less: immature vascularization, zone I, no ROP; immature retina localized to boundary of zones I and II; zone I, stage 1 or 2; zone II, stage 3; or any concern for aggressive posterior ROP.

 One to 2 weeks: immature vascularization localized to posterior zone II; or zone II, stage 2; or zone I, regressing ROP.

 Two weeks: immature vascularization localized to zone II, no ROP; zone II, stage 1; or zone II, regressing ROP.

 Two to 3 weeks: zone III, stage 1 or 2; or zone III, regressing ROP.

1. Children who have had ROP have a higher incidence of myopia, strabismus, amblyopia, macular dragging, cataracts, glaucoma, and retinal detachment. An untreated fully vascularized fundus needs examination at age 6 months to rule out these complications.

NOTE: Because of the possibility of late retinal detachments and other ocular complications, ROP patients should be followed at yearly intervals for life.

2. Acute-phase ROP screening can be discontinued when any of the following signs is present, indicating that the risk of visual loss from ROP is minimal or passed:

• Zone III retinal vascularization attained without previous zone I or II ROP. If there is doubt about the zone or if the postmenstrual age is <35 weeks, confirmatory examinations may be warranted.

 Postmenstrual age of 50 weeks and no ROP disease equivalent to or worse than zone I, any stage or zone II, stage 3.

 Full retinal vascularization in close proximity to the ora serrata (for cases treated with anti-VEGF therapy).

 If treated with anti-VEGF, follow up should be extended due to risk of ROP recurring after 65 to 70 weeks postmenstrual age, if retinal vascularization remains incomplete. Consider prophylactic laser to undeveloped avascular retina if unable to assure follow-up examinations.

8.3 Familial Exudative Vitreoretinopathy

Symptoms

Many are asymptomatic, but patients may report decreased vision depending on the stage.

Signs

(See Figure 8.3.1.)

FIGURE 8.3.1 Familial exudative vitreoretinopathy with a falciform fold.

Critical. Vascular dragging and peripheral retinal nonperfusion, most prominently temporally. Bilateral but often asymmetric. Peripheral retinal vessels have a fimbriated border. Present at birth.

Other. Peripheral neovascularization and/or fibrovascular proliferation at the border of vascular and avascular retina; temporal dragging of macula through contraction of fibrovascular tissue; radial retinal folds; vitreous hemorrhage; tractional, exudative, and/or rhegmatogenous retinal detachment; peripheral intraretinal and subretinal lipid exudation. May present with strabismus or leukocoria in childhood. Cataract, band keratopathy, neovascular glaucoma, or phthisis possible.

Differential Diagnosis

• ROP: Appears similar to FEVR, but there is lack of family history, and there should be a history of prematurity. See 8.2, Retinopathy of Prematurity.

• See 8.1, Leukocoria, for additional diagnoses in the differential including retinoblastoma, Coats disease, PFV, incontinentia pigmenti, Norrie disease, X-linked retinoschisis, and peripheral retinal nonperfusion. Positive family history and bilaterality can help distinguish from others.

Etiology

Due to defects in the Wnt signaling pathway. Often autosomal dominant, but can be autosomal recessive or X-linked. Usually no history of prematurity or oxygen therapy.

Workup

1. History: Positive family history? No history of prematurity or oxygen therapy?

2. Complete ocular examination, including dilated retinal examination looking for supernumerary vessels, vascular dragging, macular dragging, neovascularization, and tractional retinal detachment. Fluorescein angiography of both eyes (under general anesthesia if necessary) has become vital for evaluation of diagnosis of anomalous vasculature, retinal nonperfusion, and neovascularization in peripheral retina, which can lead to tractional retinal detachment and result in decreased visual outcomes.

3. All family members suspected of carrying the gene should also have dilated retinal examinations and fluorescein angiography. This may be essential to preventing family members from experiencing permanent vision loss, as this disease is typically asymptomatic.

4. Genetic testing: Commonly affected genes include FZD4, LRP5, TSPAN12, and NDP. LRP5 mutation has been associated with early onset osteoporosis. Many others are included now in genetic panels.

Treatment

Laser of peripheral avascular retina is performed if there is neovascularization and/or exudation. Scleral buckling or vitrectomy can be considered for retinal detachments. Treat amblyopia as needed. Genetic testing and examination of family members recommended.

Follow Up

FEVR is a lifelong disease. All patients should be followed throughout life to monitor for progression.

8.4 Esodeviations

Signs

(See Figure 8.4.1.)

FIGURE 8.4.1 Esotropia.

Critical. Either eye is turned inward. The nonfixating eye turns outward to fixate straight ahead when the previously fixating eye is covered during the cover-uncover test. See Appendix 3, Cover/Uncover and Alternate Cover Tests.

Other. Amblyopia, overaction of the inferior oblique muscles, dissociated vertical deviation, and/or latent nystagmus may be present.

Differential Diagnosis

FIGURE 8.4.2 Pseudoesotropia.

 Pseudoesotropia: The eyes appear esotropic; however, there is no ocular misalignment detected during cover-uncover testing. Usually, the child has a wide nasal bridge, prominent epicanthal folds, or a small interpupillary distance (see Figure 8.4.2).

 See 8.6, Strabismus Syndromes.

Types

Comitant Esotropic Deviations

A manifest convergent misalignment of the eyes in which the measured angle of esodeviation is nearly constant in all fields of gaze at distance fixation.

1. Congenital (infantile) esotropia: Manifests by age 6 months. The angle of esodeviation is usually large (>40- to 50-prism diopters) and mostly equal at distance and near fixation. Refractive error is usually normal for age (slightly hyperopic). Amblyopia is uncommon but may be present in those who do not cross-fixate. Prohibits development of binocular vision. Family history may be present. Latent nystagmus, inferior oblique overaction, and dissociated vertical deviation may develop as late findings. Congenital esotropia can occur in up to 30% of children with neurologic and developmental disorders (e.g., cerebral palsy, hydrocephalus); however, it is not necessary to perform a neurologic workup in the absence of other findings. Cycloplegic refraction should be considered first, but treatment is often surgical relatively early on in the course of the disease.

2. Acquired nonaccommodative esotropia: Convergent

misalignment of the eyes not corrected by hyperopic lenses that develops after 6 months of age. Typically starts as intermittent but can become constant over time. Esodeviation is comitant and usually smaller (20 to 35 prism diopters) than that seen in congenital esotropia. Patients may experience diplopia. Usually corrected with strabismus surgery once the angle of the esotropia becomes consistent. In children older than 6 years, this must be assumed to be posterior fossa pathology until proven otherwise and worked up with imaging emergently.

3. Accommodative esotropia: Convergent misalignment of the eyes associated with activation of the accommodative reflex. May present at 6 months to 6 years of age with the average age of onset being 2.5 years. Subtypes of accommodative esotropia:

 Refractive accommodative esotropia: These children are hyperopic in the range of +3.00 to +10.00 diopters (average, +4.75). The measured angle of esodeviation is usually moderate (20- to 30-prism diopters) and is relatively equal at distance and near fixation. Full hyperopic correction eliminates the esodeviation. The accommodative convergence-accommodation angle ratio (AC/A) is normal. Amblyopia is common at presentation.

 Nonrefractive accommodative esotropia (high AC/A ratio): The measured angle of esodeviation is greater at near fixation than at distance fixation. The refractive error may range from normal for age (slight hyperopia) to high hyperopia (may be seen in conjunction with refractive-type accommodative esotropia) or even myopia. Amblyopia is common.

• Partial or decompensated accommodative esotropia: Refractive and nonrefractive accommodative esotropias that have a reduction in the esodeviation when given full hyperopic correction, but still have a residual esodeviation. When partial, the residual esodeviation is the nonaccommodative component.

4. Sensory-deprivation esotropia: An esodeviation that occurs in a patient with a monocular or binocular condition that prevents good vision.

5. Divergence insufficiency: A convergent ocular misalignment that is greater at distance fixation than at near fixation. This is a diagnosis of exclusion and must be differentiated from divergence paralysis, which, when sudden in onset, can be associated with pontine tumors, neurologic trauma, and elevated intracranial pressure. This can be a benign condition in older patients, requiring only base out prisms in glasses. See 10.8, Isolated Sixth Cranial Nerve Palsy.

Incomitant or Noncomitant Esodeviations

The measured angle of esodeviation increases in lateral gaze at distance fixation.

1. Central nervous system pathology causing increased intracranial pressure: Acute and new onset of diplopia secondary to an acquired sixth cranial nerve palsy, which may be accompanied by nystagmus, headache, or other focal neurologic deficits depending on etiology.

2. Medial rectus restriction (e.g., thyroid disease, medial orbital wall fracture with entrapment).

3. Lateral rectus weakness (e.g., isolated sixth cranial nerve palsy, slipped or detached lateral rectus from trauma or previous surgery).

4. See 8.6, Strabismus Syndromes and 10.8, Isolated Sixth Cranial Nerve Palsy, for additional etiologies.

Other

1. Esophoria: Latent esodeviation controlled by fusion. Eyes are aligned under binocular conditions.

2. Intermittent esotropia: Esodeviation that is intermittently controlled by fusion. Becomes manifest spontaneously, especially with fatigue or illness.

Workup

1. History: Age of onset, frequency of crossing, prior therapy (e.g., glasses, patching).

2. Visual acuity of each eye, with best correction and pinhole. Color vision and stereopsis.

3. Ocular motility examination; observe for restricted movements or oblique overactions.

4. Measure the distance deviation in all fields of gaze and the near deviation in the primary position (straight ahead) using prisms (see Appendix 3, Cover/Uncover and Alternate Cover Tests). Look specifically for an esotropia increasing in either side gaze.

5. Manifest and cycloplegic refractions especially if <7 years of age.

6. Complete eye examination. Look for any cranial nerve abnormalities and causes of sensory deprivation.

7. If nonaccommodative esotropia, divergence insufficiency or paralysis, muscle paralysis, or incomitant esotropia develops acutely, an MRI brain and orbit is necessary to rule out an intracranial or orbital process, extraocular muscle pathology, bony lesion, etc. MRI should be considered for acute onset comitant esotropia in certain settings.

8. With incomitant esodeviation greater in side gaze, determine whether the lateral rectus function is deficient or the medial rectus is restricted. Forced duction testing (which may require anesthesia for children) may be necessary for that distinction (see Appendix 6, Forced Duction Test and Active Force Generation Test). Consider thyroid function tests or a workup for myasthenia gravis. Be sure to look for characteristics of strabismus syndromes (see 8.6, Strabismus Syndromes).

Treatment

In all cases, correct refractive errors of +2.00 diopters or more. In children, treat any underlying amblyopia (see 8.7, Amblyopia).

1. Congenital esotropia: Almost always requires strabismus surgery. However, prescribe glasses and initiate treatment of any underlying amblyopia prior to surgical intervention as appropriate.

2. Accommodative esotropia: Glasses must be worn full time.

a. If the patient is <6 years old, correct the hyperopia with the full cycloplegic refraction.

b. If the patient is >6 years old, attempts should be made to give as close to the fullplus refraction as possible, knowing that some may not tolerate the full prescription. Attempts to push plus lenses during the manifest (noncycloplegic) refraction until distance vision blurs may be tried to give the most plus lenses without blurring distance vision. The goal of refractive correction should be straight alignment without sacrificing visual acuity.

c. If the patient’s eyes are straight at distance with full correction, but still esotropic at near fixation (high AC/A ratio), treatment options include the following:

 Bifocals (flat-top or executive type) +2.50 or +3.00 diopter add, with top of the bifocal at the lower pupillary border.

 Echothiophate (phospholine iodide) eyedrops in both eyes nightly.

 Extraocular muscle surgery targeting the near deviation only may be indicated. This typically requires posterior fixation sutures to the muscle to modify the surgical effect for near only.

Wearing full-plus distance glasses only.

NOTE: There is no universal agreement on the treatment of patients with excess crossing at near only.

3. Nonaccommodative, partially accommodative, or decompensated accommodative esotropia: Muscle surgery is usually performed to correct the nonaccommodative deviation or the significant residual esotropia that remains when glasses are worn.

 Sensory-deprivation esotropia.

 Attempt to identify and correct the cause of poor vision.

 Amblyopia treatment.

 Give the full cycloplegic correction (in fixing eye) if the patient is <6 years of age, otherwise give as much plus as tolerated during manifest refraction.

 Muscle surgery to correct the manifest esotropia.

 All patients with low vision in one eye need to wear protective polycarbonate lens glasses at all times.

Follow Up

At each visit, evaluate for amblyopia and measure the degree of deviation with prisms (with glasses worn).

1. If amblyopia is present, see 8.7, Amblyopia, for management.

2. In the absence of amblyopia, the child is reevaluated in 3 to 6 weeks after a new prescription is given. If no changes are made and the eyes are straight, the patient should be followed up several times a year when young, decreasing to annually when stable.

3. When a residual esotropia is present while the patient wears glasses, an attempt is made to add more plus power to the current prescription. Children <6 years old should receive a new cycloplegic refraction; plus lenses are pushed without cycloplegia in older children. The maximal additional plus lens that does not blur distance vision is prescribed. If the eyes cannot be straightened with more plus power, then a decompensated accommodative esotropia has developed (see above in Section 8.4, Comitant OR Concomitant Esotropic Deviations).

Hyperopia often decreases slowly after age 5 to 7 years of age, and the strength of the glasses may need to be reduced so as not to blur distance vision. If the strength of the glasses must be reduced to improve visual acuity and the esotropia returns, then this is a decompensated accommodative esotropia.

8.5 Exodeviations

Signs

(See Figure 8.5.1.)

FIGURE 8.5.1 Exotropia.

Critical. Either eye is constantly or intermittently turned outward. On the cover-uncover test, the uncovered eye moves from the outturned position to the midline to fixate when the previously fixating eye is covered (see Appendix 3, Cover/Uncover and Alternate Cover Tests).

Other. Amblyopia, “A” pattern deviation (superior oblique overaction producing an increased deviation in downgaze compared to upgaze), “V" pattern deviation (inferior oblique overaction producing an increased deviation in upgaze compared to downgaze), and dissociated vertical deviations.

Differential Diagnosis

Pseudoexotropia: The patient appears to have an exodeviation, but no movement is noted on cover-uncover testing despite good vision in each eye. A wide interpupillary distance, a naturally large angle k (angle between the pupil center and the visual axis), or temporal dragging of the macula (e.g., from ROP, FEVR, toxocariasis, or other retinal disorders) may be responsible.

Types

1. Exophoria: A latent exodeviation controlled by fusion under conditions of normal binocular vision. Usually asymptomatic, but prolonged strenuous visual activity may cause asthenopia.

• Intermittent exotropia: A manifest deviation in which one eye demonstrates exodeviation part of the time. The most common type of exodeviation in children. Onset is usually before age 5. Frequency often increases over time. Amblyopia is rare. Usually occurs when the patient is fatigued, sick, or not attentive. Patient often closes one eye or squints in bright sunlight. This is likely due to dissociation and breakdown of their binocular alignment.

A. Clinical evaluation:

 Good control: One eye turns out at only after cover testing and the patient is able to regain fusion quickly without blinking or refixating when the cover is removed.

 Fair control: One eye turns out after cover testing and the patient can only regain fusion with blinking or refixating.

 Poor control: One eye turns out spontaneously and remains manifest for an extended period of time.

B. Good, fair, or poor control can be seen in all four types of intermittent exotropia:

 Basic: Exodeviation is approximately the same with distance and near fixation.

 True divergence excess: Exodeviation that remains greater at distance than near after a period of monocular occlusion.

 Simulated divergence excess: Exodeviation that is initially greater with distance fixation than near that becomes approximately the same after an interval of monocular occlusion.

 Convergence insufficiency: Exodeviation is greater at near than distance. Distinct from isolated convergence insufficiency. See 13.4, Convergence Insufficiency.

2. Constant exotropia: Encountered more often in older children. There are three types:

 Congenital exotropia: Also known as infantile exotropia. Presents before age 6 months with a large angle deviation. Uncommon in otherwise healthy infants and may be associated with a central nervous system or craniofacial disorder.

 Sensory-deprivation exotropia: An eye that does not see well for any reason may turn outward.

 Decompensated intermittent exotropia: A patient with long-standing intermittent exotropia that has decompensated.

 Consecutive exotropia: Follows a diagnosis of esotropia, most commonly after previous surgery for esotropia.

3. Duane syndrome, type 2: Limitation of adduction of one eye, with globe retraction and narrowing of the palpebral fissure on attempted adduction. Rarely bilateral. See 8.6, Strabismus Syndromes. May present with head turn away from affected eye.

4. Neuromuscular abnormalities:

 Third cranial nerve palsy: See 10.5, Isolated Third Cranial Nerve Palsy.

 Myasthenia gravis: See 10.11, Myasthenia Gravis.

 Internuclear ophthalmoplegia: See 10.13, Internuclear Ophthalmoplegia.

5. Dissociated horizontal deviation: A change in horizontal ocular alignment caused by a change in the balance of visual input from the two eyes. Not related to accommodation. Seen clinically as a spontaneous unilateral exodeviation or an exodeviation of greater magnitude in one eye during prism and alternate cover testing.

6. Orbital disease (e.g., tumor, idiopathic orbital inflammatory syndrome): Proptosis and restriction of ocular motility are usually evident. See 7.1, Orbital Disease.

7. Isolated convergence insufficiency: Usually occurs in patients >10 years old. Blurred near vision, asthenopia, or diplopia when reading. An exophoria at near fixation, but straight or small exophoria at distance fixation. Must be differentiated from convergence paralysis. See 13.4, Convergence Insufficiency.

8. Convergence paralysis: Similar to convergence insufficiency, but with a relatively acute onset, an exotropia at near, and an inability to overcome base out prism. Often secondary to an intracranial lesion.

Workup

1. Evaluate visual acuity of each eye, with correction and pinhole, to evaluate for amblyopia. Color vision and stereopsis.

2. Perform motility examination; observing for restricted eye movements or signs of Duane syndrome.

3. Measure the exodeviation in all cardinal fields of gaze at distance and in primary position (straight ahead) at near, using prisms. See Appendix 3, Cover/Uncover and Alternate Cover Tests.

4. Perform pupillary, slit lamp, and fundus examinations; check for causes of sensory deprivation (if poor vision).

5. Refraction (cycloplegic or manifest depending on age of the patient).

6. Consider workup for myasthenia gravis when suspected or evidence of fatigability. See 10.11, Myasthenia Gravis.

7. Consider an MRI of the brain and orbits when neurologic or orbital disease is suspected.

Treatment

In all cases, correct significant refractive errors and treat amblyopia.

See 8.7, Amblyopia.

1. Exophoria:

 No treatment necessary unless it progresses to intermittent exotropia.

2. Intermittent exotropia:

 Good control: Correct refractive error and treat amblyopia if present. Follow patient closely.

 Fair control: Correct refractive error and treat amblyopia if present. Nonsurgical treatment may be indicated and include occlusion therapy with alternate daily patching to reduce suppression or additional minus lenses to stimulate accommodative convergence. Muscle surgery may be considered to maintain normal binocular vision.

 Poor control: Correct refractive error and treat amblyopia if present. Nonsurgical treatments as described above may be attempted. Muscle surgery is often indicated. Bifixation or peripheral fusion can occasionally be attained.

3. Sensory-deprivation exotropia:

 Correct the underlying cause, if possible.

 Treat any amblyopia.

 Muscle surgery may be performed for manifest exotropia.

 When one eye has very poor vision, protective glasses (polycarbonate lens glasses) should be worn at all times to protect the good eye.

4. Congenital exotropia:

 Muscle surgery within a year of onset, as in patients with congenital esotropia.

5. Consecutive exotropia:

 Additional muscle surgery may be considered.

 Prism correction in glasses can be used.

 Over-minus or under-plus correction can stimulate accommodative convergence.

6. Dissociated horizontal deviation:

 Muscle surgery may be considered.

7. Duane syndrome: See 8.6, Strabismus Syndromes.

8. Third cranial nerve palsy: See 10.5, Isolated Third Cranial Nerve Palsy.

9. Convergence insufficiency: See 13.4, Convergence Insufficiency.

10. Convergence paralysis:

 Base-in prisms at near to alleviate diplopia.

 Plus lenses if accommodation is also weakened.

Follow Up

1. If amblyopia is present, see 8.7, Amblyopia.

2. If no amblyopia is present, then reexamine every 3 to 6 months depending on the age of the patient and the control of the deviation. The parents and patient are asked to return sooner if the deviation increases, becomes more frequent, stays out longer, or if the patient begins to close one eye.

8.6 Strabismus Syndromes

Motility disorders that demonstrate typical features of a particular syndrome.

Syndromes

• Duane syndrome: A congenital motility disorder, usually unilateral (85%), characterized by limited abduction, limited adduction, or both. The globe retracts and the eyelid fissure narrows on adduction. In unilateral cases, the strabismus will be incomitant and the patient will often adopt a face turn to allow them to use both eyes together. May be associated with deafness and limb or vertebral abnormalities. Classified into three types:

 Type 1 (most common): Limited abduction. Primary position frequently esotropia. In unilateral cases, nearly always with face turn toward affected side.

 Type 2 (least common): Limited adduction. Primary position usually exotropia. In unilateral cases, often with face turn away from affected side.

• Type 3: Limited abduction and adduction. Esotropia, exotropia, or no primary position deviation. Significant globe retraction.

 Brown syndrome: A motility disorder characterized by limitation of elevation in adduction. Elevation in abduction is normal. Typically, eyes are aligned in primary gaze, although a vertical diplopia with chin-up head position or face turn can be present. Usually congenital, but may be idiopathic or acquired secondary to trauma, surgery, or inflammation in the area of the trochlea. Bilateral in 10% of patients.

 Monocular elevation deficiency (double elevator palsy): Congenital. Unilateral limitation of elevation in all fields of gaze secondary to restriction of the inferior rectus or paresis of the inferior oblique and/or superior rectus. There may be hypotropia of the involved eye that increases in upgaze. Ptosis or pseudoptosis may be present in primary gaze. The patient may assume a chin-up position to maintain fusion if a hypotropia in primary gaze is present.

 Mobius syndrome: Rare congenital condition associated with both sixth and seventh cranial nerve palsies. Esotropia is usually present. Limitation of abduction and/or adduction. A unilateral or bilateral facial nerve palsy is either partial or complete. Other cranial nerve palsies as well as deformities of the limbs, chest, and tongue may occur.

 Congenital fibrosis syndrome: Congenital group of disorders with restriction and fibrous replacement of the extraocular muscles. Usually involves all of the extraocular muscles with total external ophthalmoplegia and ptosis. Most commonly, both eyes are directed downward, so the patient assumes a chin-up position to see. Often autosomal dominant, but other inheritance patterns may be present. Genetic testing is recommended in patients with suspected congenital fibrosis syndrome.

Workup

1. History: Age of onset? History of trauma? Family history? History of other ocular or systemic diseases?

2. Complete ophthalmic examination, including alignment in all fields of gaze. Note head position. Look for retraction of globe and narrowing of interpalpebral fissure in adduction (common in Duane syndrome).

3. Pertinent physical examination, including cranial nerve evaluation.

4. Radiologic studies (e.g., MRI or CT scan) may be indicated for acquired, atypical, or progressive motility disturbances, especially if associated neurologic or developmental abnormalities.

5. Forced duction testing is used to differentiate the two etiologies of monocular elevation deficiency (test will be positive with inferior rectus fibrosis and negative with superior rectus and inferior oblique paresis). Forced ductions can also confirm the diagnosis of Brown syndrome.

Treatment

1. Treatment is usually indicated for a cosmetically significant abnormal head position or if a significant horizontal or vertical deviation exists in primary gaze.

2. Surgery, when indicated, depends on the particular motility disorder, extraocular muscle function, and the degree of abnormal head position.

Follow Up

Follow up depends on the condition or conditions being treated.

8.7 Amblyopia

Symptoms

Usually none. Often discovered when decreased vision is detected via visual acuity testing of each eye individually. A history of patching, strabismus, or muscle surgery as a child may be elicited.

NOTE: Amblyopia occasionally occurs bilaterally as a result of bilateral visual deprivation (e.g., congenital cataracts not treated within the earliest months of life).

Signs

Critical. Poorer vision in one eye that is not entirely improved with refraction and not entirely explained by an organic lesion. In anisometropic amblyopia, the involved eye nearly always has a higher refractive error. The decrease in vision develops during the first decade of life. Central vision is primarily affected, while the peripheral visual field usually remains normal.

Other. Individual letters are more easily read than a full line (crowding phenomenon). In reduced illumination, the visual acuity of an amblyopic eye is reduced much less than an organically diseased eye (neutral-density filter effect).

NOTE: Amblyopia, when severe, may cause a trace relative afferent pupillary defect. Care must be taken to be sure that the light is directed along the same axis in each eye, particularly in patients with strabismus. Directing the light off-axis may result in a falsepositive result.

Etiology

• Strabismus: Most common form (along with anisometropia). The eyes are misaligned. Vision is worse in the consistently deviating, nonfixating eye. Strabismus can lead to or be the result of amblyopia.

 Anisometropia: Most common form (along with strabismus). A large difference in refractive error (usually >1.50 diopters) between the two eyes. Can be seen in cases of eyelid hemangioma or congenital ptosis inducing astigmatism.

 Media opacity: A unilateral cataract, corneal scar, or PFV may cause a preference for the other eye and thereby cause amblyopia.

 Occlusion: Amblyopia that occurs in the fellow eye as a result of too much patching or excessive use of atropine. Prevented by examining at appropriate intervals (1 week per year of age), patching part-time, or using the full cycloplegic refraction when using atropine.

Workup

1. History: Eye problem in childhood such as misaligned eyes, patching, or muscle surgery?

2. Ocular examination to rule out an organic cause for the reduced vision.

3. Cover-uncover test to evaluate eye alignment. See Appendix 3, Cover/Uncover and Alternate Cover Tests.

4. Cycloplegic refraction of both eyes.

Treatment

1. Patients younger than 12 years:

• Appropriate spectacle correction (full cycloplegic refraction or reduce the hyperopia in both eyes symmetrically >1.50 diopters). If vision remains reduced after period of refractive adaptation (6 to 12 weeks), begin patching or penalization of fellow eye.

 Patching: Patch the eye with better corrected vision 2 to 6 hours/day. Follow-up visits should be scheduled for 1 week per year of age (e.g., 3 weeks for a 3-year- old). Adhesive patches placed directly over the eye are most effective. Patches worn over glasses are not ideal due to the risk of children peeking. If a patch causes local irritation, use tincture of benzoin on the skin before applying the patch and use warm water compresses on the patch before removal.

 Penalization with atropine: Atropine 1% once daily (used with glasses) has been shown to be equally effective as patching in mild-to-moderate amblyopia (20/100 or better). If vision does not improve, the effect of the atropine can be increased by removing the hyperopic lens from the glasses of the nonamblyopic eye. If the child is experiencing difficulty with school work with the use of atropine, he/she can wear full hyperopic correction with a +2.50 bifocal during school or have the atropine drops instilled on weekends only.

 Optical degradation: Use a high plus lens (e.g., +9.00 diopters or an aphakic contact lens) to blur the image. If the child is highly myopic, the minus lens from the preferred eye may be removed.

2. Continue patching until the vision is equalized or shows no improvement after three compliant cycles of patching. If a recurrence of amblyopia is likely, use part-time patching to maintain improved vision.

3. If occlusion amblyopia (a decrease in vision in the patched eye) develops, patch the opposite eye for a short period (e.g., 1 day per year of age), and repeat the examination.

4. In strabismic amblyopia, delay strabismus surgery until the vision in the two eyes is equal, or maximal vision has been obtained in the amblyopic eye.

5. If treatment of amblyopia fails or the patient presents outside of treatment age range, protective glasses should be worn to prevent accidental injury to the nonamblyopic eye. Any child who does not have vision improved to at least 20/40 needs to wear eye protection during sports (one-eyed athlete rule).

6. Treatment of media opacity: Remove the media opacity and begin patching the nonamblyopic eye.

7. Treatment of anisometropic amblyopia: Give the appropriate spectacle correction at the youngest age possible. If vision remains reduced after period of refractive adaptation (6 to 12 weeks), begin patching or penalization of fellow eye.

Follow Up

Long-term follow up depends on the age of the patient, the amount of prescribed patching, and the severity of the amblyopia.

8.8 Pediatric Cataract

Signs

(See Figure 8.8.1.)

FIGURE 8.8.1 Pediatric nuclear cataract.

Critical. Opacity of the lens at birth.

Other. A white fundus reflex (leukocoria), absent or asymmetric red pupillary reflex, abnormal eye movements (nystagmus) in one or both eyes, and strabismus. Infants with bilateral cataracts may be noted to be visually inattentive. In patients with a monocular cataract, the involved eye may be smaller. A cataract alone does not cause a relative afferent pupillary defect.

Differential Diagnosis

See 8.1, Leukocoria.

Etiology

 Idiopathic (most common)

 Congenital

 Familial: Can be autosomal dominant (most common), autosomal recessive, or rarely part of an X-linked recessive Nance-Horan syndrome. Phenotype varies in terms of cataract morphology and timing of clinical onset.

 Metabolic disease:

 Galactosemia: Cataract may be the sole manifestation when galactokinase deficiency is responsible. A deficiency of galactose-1-phosphate uridyl transferase may produce mental retardation and symptomatic cirrhosis along with cataracts. The typical oil droplet opacity may or may not be seen. Incidence and onset of cataract may vary according to type of galactosemia (i.e., mutation of uridyl transferase, galactokinase, or epimerase). Cataract may be reversible with appropriate dietary modifications.

 PFV: Usually unilateral, very rarely bilateral. The involved eye is usually slightly smaller than the normal fellow eye. Examination after pupil dilatation may reveal a plaque of fibrovascular tissue behind the lens with elongated ciliary processes extending to it. Progression of the lens opacity often leads to angle-closure glaucoma. If bilateral, 90% are associated with systemic abnormalities and require further workup.

 Rubella: "Pearly white" nuclear cataract, "salt-and-pepper" chorioretinitis, microphthalmos, corneal clouding, and poorly dilating pupils. Glaucoma may occur with congenital rubella but usually does not occur in the presence of a rubella cataract. Associated hearing defects and heart abnormalities are common.

 Renal syndromes:

 Lowe syndrome (oculocerebrorenal syndrome): Opaque lens, congenital glaucoma, renal disease, and mental retardation. X-linked recessive. Patients’ mothers may have small cataracts.

 Alport syndrome: Glomerulonephritis, hearing loss, eye abnormalities including cataract, anterior lenticonus, and keratoconus. Most commonly X- linked or autosomal recessive.

• Others: Intrauterine infection, chromosomal disorders, aniridia, systemic syndromes, metabolic abnormalities, craniofacial syndromes, musculoskeletal disorders, and anterior segment dysgenesis.

• Acquired: Trauma, drugs, uveitis, metabolic/endocrine abnormalities, radiation.

Types

1. Zonular (lamellar): Most common type of congenital cataract. White opacities that surround the nucleus with alternating clear and white cortical lamella resembling an onion skin.

2. Polar: Small opacities of the lens capsule and adjacent cortex on the anterior or posterior pole of the lens. Anterior polar cataracts usually are small and tend to grow very little over time. They may be associated with anisometropia and anisometropic amblyopia. Posterior polar cataracts are variable and may grow significantly, causing decreased vision.

3. Nuclear: Opacity within the embryonic/fetal nucleus.

4. Posterior lenticonus: A posterior protrusion, usually opacified, in the posterior capsule.

5. Posterior subcapsular: Opacification of the area immediately anterior to the posterior capsule. Most often acquired due to steroid medications, diabetes, or ionizing radiation.

Workup

1. History: Maternal illness or drug ingestion during pregnancy? Systemic or ocular disease in the infant or child? Radiation exposure or trauma? Family history of congenital cataracts? Steroid use?

2. Visual assessment of each eye individually by using techniques for nonverbal children (Teller cards, following small toys or a light).

3. Ocular examination: Attempt to determine the visual significance of the cataract by evaluating the size and location of the cataract and whether the retina can be seen with a direct ophthalmoscope or retinoscope when looking through an undilated pupil. A blunted retinoscopic reflex suggests the cataract is visually significant. Cataracts ≥3 mm in diameter usually but not always affect vision. Cataracts ≤3 mm may not be inherently visually significant but have been associated with amblyopia secondary to induced anisometropia. Check for signs of associated glaucoma (see 8.11, Congenital/Infantile Glaucoma) and examine the optic nerve and retina for abnormalities.

4. Cycloplegic refraction.

5. B-scan US may be helpful when the fundus view is obscured. It is essential to rule out posterior PFV in unilateral cataract cases where the fundus is not visible.

6. Ultrasound biomicroscopy can be helpful in cases of anterior segment dysgenesis or PFV.

7. Bilateral cataracts suggest a genetic or metabolic etiology; medical examination by a pediatrician looking for associated abnormalities is recommended.

8. Red blood cell (RBC) galactokinase activity (galactokinase levels) with or without RBC galactose-1-phosphate uridyl transferase activity to rule out galactosemia. The latter test is performed routinely on all infants in the United States as part of the newborn screen.

9. Other tests as suggested by the systemic or ocular examination. The chance that one of these conditions is present in a healthy child is remote.

• Urine: Amino acid quantitation (Alport syndrome), amino acid content (Lowe syndrome).

 Antibody titers for rubella and other suspected intrauterine infections.

Treatment

1. Referral to a pediatrician to treat any underlying disorder.

2. Treat associated ocular diseases.

3. Cataract extraction, usually within days to weeks of discovery to prevent irreversible amblyopia, is performed in the following circumstances:

 Visual axis is obstructed, and the eye’s visual development is at risk.

 Cataract progression threatens the health of the eye (e.g., in PFV).

4. After cataract extraction, treat amblyopia (see 8.7, Amblyopia).

5. A dilating agent (e.g., phenylephrine 2.5% t.i.d. or cyclopentolate 1% b.i.d.) may be used as a temporizing measure, allowing peripheral light rays to pass around the lens opacity and reach the retina. If the cataract is small, and the red reflex is good around the peripheral lens, this may be the only treatment needed.

6. Unilateral cataracts that are not large enough to obscure the visual axis may still result in amblyopia despite not needing cataract extraction. Treat amblyopia as above.

Follow Up

1. Infants and young children who do not undergo surgery are monitored closely for cataract progression and amblyopia.

2. Amblyopia is less likely to develop in older children even if the cataract progresses. Therefore, this age group is followed less frequently.

NOTE: Children with rubella must be isolated from pregnant women.

8.9 Ophthalmia Neonatorum (Newborn Conjunctivitis)

Signs

Critical. Purulent, mucopurulent, or mucoid discharge from one or both eyes in the first month of life with diffuse conjunctival injection.

Other. Eyelid edema and chemosis.

Differential Diagnosis

 Dacryocystitis: Swelling and erythema just below the inner canthus. See 6.9, Dacryocystitis/Inflammation of the Lacrimal Sac.

 Nasolacrimal duct obstruction: See 8.10, Congenital Nasolacrimal Duct Obstruction.

 Congenital glaucoma: See 8.11, Congenital/Infantile Glaucoma.

Etiology

 Chemical: Seen within a few hours of instilling a prophylactic agent (e.g., silver nitrate). Lasts no more than 24 to 36 hours. Rarely seen now that erythromycin is used routinely. Gentamicin should be avoided since it may be associated with a toxic reaction.

 Neisseria gonorrhoeae: Usually seen within 3 to 4 days after birth. May present with mild conjunctival hyperemia to severe chemosis, copious discharge, rapid corneal ulceration, or corneal perforation. Gram-negative intracellular diplococci seen on Gram stain.

 Chlamydia trachomatis: Usually presents within first week or two of birth with mild swelling, hyperemia, tearing, and primarily mucoid discharge. Can progress resulting in increased eyelid swelling and discharge. May form pseudomembranes with bloody discharge. Giemsa stain may show basophilic intracytoplasmic inclusion bodies in conjunctival epithelial cells, polymorphonuclear leukocytes, or lymphocytes. Diagnosis usually made with various molecular tests including immunoassay (e.g., ELISA, enzyme immunoassay, direct antibody tests), polymerase chain reaction (PCR), or DNA hybridization probe.

 Bacteria: Staphylococci (including methicillin-resistant Staphylococcus aureus), streptococci, and gram-negative species may be seen on Gram stain.

 Herpes simplex virus: Initially asymptomatic. May present with a cloudy cornea, conjunctival injection, and tearing. Classic herpetic vesicles on the eyelid margins are not always seen. A corneal dendrite which rapidly progresses to a geographic ulcer may occur. Can see multinucleated giant cells on Giemsa stain.

Workup

1. History: Previous or concurrent venereal disease in the mother? Were cervical cultures performed during pregnancy?

2. Ocular examination with use of fluorescein staining to look for corneal involvement.

3. Conjunctival scrapings for two slides: Gram and Giemsa stain.

• Technique: Irrigate the discharge out of the fornices and place a drop of topical anesthetic (e.g., proparacaine) in the eye. Scrape the palpebral conjunctiva of the lower eyelid with a flame-sterilized spatula (after it cools off) or with a fresh calcium alginate swab (moistened with liquid broth media). Place scrapings on slide (or culture media).

4. Conjunctival cultures with blood and chocolate agars. Chocolate agar should be placed in an atmosphere of 2% to 10% carbon dioxide immediately after being plated. Technique as described above.

5. Scrape the conjunctiva for the chlamydial immunofluorescent antibody test or PCR, if available.

6. Viral culture: Moisten the applicator and roll it along the palpebral conjunctiva. Place the end of the applicator directly into the viral transport medium and mix vigorously to achieve inoculation.

7. Systemic evaluation by primary care provider.

Treatment

Initial therapy is based on the results of the Gram and Giemsa stains if they can be examined immediately. Therapy is then modified according to the culture results and clinical response.

1. No information from stains, no particular organism suspected: Erythromycin ointment q.i.d. plus erythromycin elixir 50 mg/kg/d in four divided doses for 2 to 3 weeks.

2. Suspect chemical (e.g., silver nitrate) toxicity: Discontinue offending agent. No treatment or preservative-free artificial tears q.i.d. Reevaluate in 24 hours.

3. Suspect chlamydial infection: Erythromycin elixir 50 mg/kg/d orally in four divided doses for 14 days, plus erythromycin ointment q.i.d. Alternatively, azithromycin 20 mg/kg orally for 3 days can be used. Topical therapy alone is not effective. If confirmed by culture or immunofluorescent stain, treat the mother and her sexual partners with one of the following:

• Doxycycline 100 mg p.o. b.i.d. for 7 days (for women who are neither breastfeeding nor pregnant). If breastfeeding or pregnant, one of the following regimens may be used: azithromycin 1 g as a single dose, amoxicillin 500 mg p.o. t.i.d. for 7 days, or erythromycin 250 to 500 mg p.o. q.i.d. for 7 days.

NOTE: Inadequately treated chlamydial conjunctivitis in a neonate can lead to chlamydial otitis or pneumonia.

NOTE: All neonates with chlamydial infection should also be evaluated for N. gonorrhoeae infection.

4. Suspect N. gonorrhoeae:

 Saline irrigation of the conjunctiva and fornices until discharge gone.

 Hospitalize and evaluate for disseminated gonococcal infection with careful physical examination (especially of the joints). Blood and cerebrospinal fluid cultures are obtained if a culture-proven infection is present.

 Ceftriaxone 25 to 50 mg/kg intravenously (i.v.) or intramuscularly (i.m.) (not to exceed 125 mg) as a single dose or cefotaxime 100 mg/kg i.v. or i.m. as a single dose. In penicillin-allergic patients or cephalosporin-allergic patients, an infectious disease consult is recommended. If sensitivities are not initially available, ceftriaxone is the treatment of choice. Systemic antibiotics sufficiently treat gonococcal conjunctivitis, and topical antibiotics are not necessary.

 Topical saline lavage q.i.d. to remove any discharge.

 All neonates with gonorrhea should also be treated for chlamydial infection with erythromycin elixir 50 mg/kg/d in four divided doses for 14 days.

NOTE: If confirmed by culture, the mother and her sexual partners should be treated appropriately for both gonorrhea and chlamydia infections.

5. Gram-positive bacteria with no suspicion of gonorrhea and no corneal involvement: Bacitracin ointment q.i.d. for 2 weeks.

6. Gram-negative bacteria with no suspicion of gonorrhea and no corneal involvement: Gentamicin, tobramycin, or ciprofloxacin ointment q.i.d. for 2 weeks.

7. Bacteria on Gram stain and corneal involvement: Hospitalize, workup, and treat as discussed in 4.11, Bacterial Keratitis.

8. Suspect herpes simplex virus: The neonate (under 1 month of age), regardless of the presenting ocular findings, should be treated with acyclovir intravenously as well as with vidarabine 3% ointment five times per day or ganciclovir 0.15% gel five times per day or trifluridine 1% drops nine times per day. Prompt initiation of intravenous acyclovir may prevent dissemination of the HSV infection and spread to the CNS. Topical therapy is optional when systemic therapy is instituted. In full-term infants, the dosage for acyclovir is 60 mg/kg/d divided into three doses. If infection is limited to the skin, eye, and mouth, it is administered intravenously for 14 days. Treatment duration is extended to 21 days if the disease is disseminated or involves the central nervous system. Consultation with a pediatric infectious disease specialist is recommended. For children with recurrent ocular lesions, oral suppressive therapy with acyclovir (20 mg/kg b.i.d.) may be of benefit.

Follow Up

1. Initially examine daily as an inpatient or outpatient.

2. If the condition worsens (e.g., corneal involvement develops), reculture and hospitalize. Therapy and follow up are tailored according to the clinical response and the culture results.

8.10 Congenital Nasolacrimal Duct

Obstruction

Signs

Critical. Wet-looking eye or tears flowing over the eyelid, moist or dried mucopurulent material on the eyelashes (predominantly medially), and reflux of mucoid or mucopurulent material from the punctum when pressure is applied over the lacrimal sac (where the lower eyelid abuts the nose). The eye is otherwise white. Symptoms usually appear in the first 3 months of life.

Other. Erythema of the surrounding skin, redness and swelling of the medial canthus, and increased size of tear meniscus. May become infected and occasionally spread from the nasolacrimal duct, resulting in conjunctivitis (possibly recurrent). Preseptal cellulitis or dacryocystitis may rarely develop.

Differential Diagnosis

 Conjunctivitis: See 5.1, Acute Conjunctivitis.

 Congenital anomalies of the upper lacrimal drainage system: Atresia of the lacrimal puncta or canaliculus.

 Dacryocele: Bluish, cystic, firm mass located just below the medial canthal angle. Caused by both distal and proximal obstruction of the nasolacrimal apparatus. Most often presents within the first week of life.

 Congenital glaucoma: Classic findings are tearing, blepharospasm, corneal clouding, and a large eye (buphthalmos). See 8.11, Congenital/Infantile Glaucoma.

 Other causes of tearing: Entropion/trichiasis, corneal defects, foreign body under the upper eyelid.

Etiology

Usually the result of a congenitally imperforate membrane at the distal end of the nasolacrimal duct over the valve of Hasner.

Workup

1. Exclude other causes of tearing, particularly congenital glaucoma. See 8.11, Congenital/Infantile Glaucoma.

2. Palpate over the lacrimal sac; reflux of mucoid or mucopurulent discharge from the punctum confirms the diagnosis. May also use the dye disappearance test. Place fluorescein in both eyes. Check in 10 minutes; fluorescein can be noted in the nose in a normal eye and will remain pooling in the eye with congenital nasolacrimal duct obstruction.

Treatment

1. Digital pressure to lacrimal sac q.i.d. The parent is taught to place his or her index finger over the child’s common canaliculus (inner corner of the eye) and apply pressure in an inward and downward fashion.

2. Topical antibiotic (e.g., polymyxin/trimethoprim q.i.d.) as needed to control mucopurulent discharge if present.

3. In the presence of acute dacryocystitis (red, swollen lacrimal sac), a systemic antibiotic is needed. See 6.9, Dacryocystitis/Inflammation of the Lacrimal Sac.

4. Most cases open spontaneously with this regimen by 6 months to 1 year of age. Probing should be considered if the nasolacrimal duct obstruction persists beyond a year of age. Probe earlier if recurrent or persistent infections of the lacrimal system develop or at the request of the parents. Most obstructions are corrected after the initial probing, but repeat sessions are sometimes needed. If primary and secondary probings fail, use of balloon dacryoplasty or silicone tubing placement into the nasolacrimal duct (left in place for weeks to months) may be necessary. Consider dacryocystorhinostomy as a last resort.

Follow Up

Routine follow up unless surgery is indicated, sooner if the situation worsens or acute dacryocystitis is present. Monitor for the development of anisometropic amblyopia.

8.11 Congenital/Infantile Glaucoma

Signs

(See Figure 8.11.1.)

FIGURE 8.11.1 Buphthalmos of right eye in congenital glaucoma.

Critical. Enlarged globe and corneal diameter (horizontal corneal diameter >12 mm before 1 year of age is suggestive), corneal edema, Haab striae (curvilinear tears in Descemet membrane of the cornea, with scalloped edges with or without associated stromal haze), increased cup/disc ratio, high intraocular pressure (IOP), axial myopia, commonly bilateral (80%). Classic findings are tearing, photophobia, blepharospasm, corneal clouding, and a large eye (buphthalmos).

Other. Corneal stromal scarring or opacification; high iris insertion on gonioscopy; other signs of iris dysgenesis, including heterochromia, may exist.

Differential Diagnosis

 Megalocornea: Bilateral horizontal corneal diameter usually >13 mm, with normal corneal thickness and endothelium, IOP, and cup/disc ratio. Radial iris transillumination defects may be seen. Usually X-linked recessive (boys affected, female carriers may have greater than normal corneal diameters) and may be associated with developmental delay (Neuhauser syndrome, autosomal recessive).

 Trauma from forceps during delivery: May produce tears in the Descemet membrane and localized corneal edema; tears are typically vertical or oblique. Corneal diameter is normal. Usually unilateral and must have history of forceps use to make diagnosis.

 Congenital hereditary endothelial dystrophy: Bilateral fullthickness corneal edema at birth with a normal corneal diameter and axial length. IOP may be falsely elevated by increased corneal thickness and hysteresis but true associated infantile glaucoma has been reported. See 4.25, Corneal Dystrophies.

 Posterior polymorphous dystrophy: Can present in infancy as bilateral but asymmetric cloudy edematous corneas with characteristic endothelial abnormalities. Normal corneal diameter, axial length, and IOP, but carries lifetime glaucoma risk. Abnormal endothelium may be seen in one parent. See 4.25, Corneal Dystrophies.

 Mucopolysaccharidoses and cystinosis: Some inborn errors of metabolism produce cloudy corneas in infancy or early childhood, usually not at birth. The corneal diameter and axial length are normal. IOP is rarely elevated and, if so, usually later in childhood. Always bilateral.

 Nasolacrimal duct obstruction: No photophobia, clear cornea, normal corneal size and axial length, normal IOP. See 8.10, Congenital Nasolacrimal Duct Obstruction.

 Large eye without other signs of glaucoma can be seen in overgrowth syndromes (e.g., hemihypertrophy) and phakomatoses (e.g., neurofibromatosis, Sturge-Weber) in the absence of glaucoma (although these diagnoses may carry a high risk of glaucoma). May also be autosomal dominant variant without glaucoma.

Etiology

Common

 Primary congenital glaucoma: Not associated with other ocular or systemic disorders. Diagnosed after other causes of glaucoma have been ruled out. Caused by incomplete differentiation of the trabecular meshwork during embryogenesis (e.g., goniodysgenesis).

 Glaucoma following cataract surgery: Most common form of pediatric glaucoma. Typically in older children. All children undergoing cataract surgery are at lifelong risk.

Less Common

 Sturge-Weber syndrome: Usually unilateral (90%); ipsilateral port-wine mark almost always involving eyelid(s), cerebral calcifications/atrophy, and seizures/developmental delay (central nervous system may not be involved at all); not familial. See 13.13, Phakomatoses.

Rare

 Other anterior segment dysgeneses: Axenfeld-Rieger spectrum, Peters anomaly, others. See 8.12, Developmental Anterior Segment and Lens Anomalies/Dysgenesis.

 Lowe syndrome (oculocerebrorenal syndrome): Cataract, glaucoma, developmental delay, and renal disease; X-linked recessive.

 Congenital rubella: Glaucoma, cataract, "salt-and-pepper" retinopathy, hearing and cardiac defects (usually peripheral pulmonic stenosis).

 Aniridia: Absence of most of iris, often with only a rudimentary iris stump visible on gonioscopy. Associated with cataracts, glaucoma, macular hypoplasia, and nystagmus. See 8.12, Developmental Anterior Segment and Lens Anomalies/Dysgenesis.

 Others: Neurofibromatosis, PFV, Weill-Marchesani syndrome, Rubinstein-Taybi syndrome, covert trauma, steroid-induced infantile glaucoma, complication of ROP, and intraocular tumors.

Workup

1. History: Other systemic abnormalities? Rubella infection during pregnancy? Birth trauma? Family history of congenital glaucoma?

2. Ocular examination, including a visual acuity assessment of each eye separately, measurement of horizontal corneal diameters (measured with calipers or templates), IOP measurement, and a slit lamp or portable slit lamp examination to evaluate for corneal edema and Haab striae. Retinoscopy to estimate refractive error looking for axial myopia. A dilated fundus examination is performed to evaluate the optic disc and retina if able to view through cornea.

3. EUA is performed in cases too difficult to evaluate in the office and in those for whom surgical treatment is considered. Horizontal corneal diameter, IOP measurement, pachymetry, retinoscopy, gonioscopy, and ophthalmoscopy are performed. Axial length is measured with ultrasound (A-scan). At 40 gestational weeks, normal mean axial length is 17 mm. This increases to 20 mm on average by age 1 year. Axial length progression may also be monitored by successive cycloplegic refractions or serial ultrasounds. Disc photos may be taken.

NOTE: IOP may be reduced by general anesthesia, particularly halothane (sevoflurane or desflurane less likely), and over ventilation (low end-tidal CO2); IOP may be elevated with ketamine hydrochloride, succinylcholine, endotracheal intubation (for 2 to 5 minutes), pressure from the anesthetic mask, speculum use, or inadequate ventilation with elevated end-tidal CO2.

Treatment

Definitive treatment is surgical, particularly in primary congenital glaucoma. Medical therapy is utilized as a temporizing measure before surgery and to help clear the cornea in preparation for possible goniotomy.

1. Medical:

 Oral carbonic anhydrase inhibitor (e.g., acetazolamide, 15 to 30 mg/kg/d in three or four divided doses): Most effective.

 Topical carbonic anhydrase inhibitor (e.g., dorzolamide or brinzolamide b.i.d.): Less effective; better tolerated.

 Topical beta-blocker (e.g., levobunolol or timolol, 0.25% if <1 year old or 0.5% if older b.i.d.): Important to avoid in asthma patients (betaxolol preferable).

 Prostaglandin analogs (e.g., latanoprost q.h.s.).

NOTE: Brimonidine is contraindicated in children under the age of 1 year because of the risk of apnea/hypotension/bradycardia/hypothermia from blood-brain permeability. Caution should be used in children under 5 years old or <20 kg or intracranial pathology (such as Sturge-Weber syndrome).

2. Surgical: Nasal goniotomy (incising the trabecular meshwork with a blade or needle under gonioscopic visualization) is the procedure of choice, although some surgeons initially recommend trabeculotomy. Miotics are sometimes used to constrict the pupil before a surgical goniotomy. If the cornea is not clear, trabeculotomy (opening the Schlemm canal from a scleral approach ab externo into the anterior chamber) or endoscopic goniotomy can be performed. If the initial goniotomy is unsuccessful, a temporal goniotomy may be tried. Trabeculectomy or tube shunt may be performed following failed angle incision operations. Cyclodestruction of the ciliary processes through cyclophotocoagulation or cryotherapy may also be an option to decrease aqueous production in certain circumstances.

NOTE: Amblyopia is the most common cause of visual loss in pediatric glaucoma and should be treated appropriately. See 8.7, Amblyopia.

Follow Up

1. Repeated examinations, under anesthesia as needed, to monitor corneal diameter and clarity, IOP, cup/disc ratio, and refraction/axial length.

2. These patients must be followed throughout life to monitor for progression.

3. Other forms of pediatric glaucoma in older children include uveitic glaucoma, traumatic glaucoma, juvenile open-angle glaucoma (autosomal dominant), and others.

8.12 Developmental Anterior Segment and Lens Anomalies/Dysgenesis

Unilateral or bilateral congenital abnormalities of the cornea, iris, anterior chamber angle, and lens.

Specific Entities

FIGURE 8.12.1 Axenfeld-Rieger anomaly.

FIGURE 8.12.2 Peters anomaly.

FIGURE 8.12.3 Microspherophakia.

 Microcornea: Horizontal corneal diameter small for age. May be isolated or associated with microphthalmia, cataract, or nanophthalmos.

 Posterior embryotoxon: A prominent, anteriorly displaced Schwalbe line. Higher risk for the development of early-onset glaucoma. May be normal or seen in association with Axenfeld- Rieger and Alagille syndromes.

 Axenfeld-Rieger spectrum: Ranges from posterior embryotoxon and iris strands inserting onto Schwalbe line or the cornea to more severe iris malformations including polycoria and corectopia. Glaucoma develops in 50% to 60% of patients. Usually autosomal dominant mutations of PITX2 and FOXC1, although others have been implicated. May be associated with abnormal teeth (e.g., microdontia, conical teeth, hypodontia), skeletal abnormalities, and redundancy of the periumbilical skin. Growth hormone deficiency, cardiac defects, deafness, and mental retardation may be seen (see Figure 8.12.1).

 Peters anomaly: Failure of the lens to form properly from the surface ectoderm and completely detach from surface epithelium during 4 to 7 weeks gestation. Central corneal opacity, usually with iris strands that extend from the collarette to a posterior corneal defect behind the scar. The lens may be clear and normally positioned, cataractous and displaced anteriorly (making the anterior chamber shallow), or adherent to the corneal defect. “Peters plus” syndrome is characterized by an associated skeletal dysplasia with short stature and is more common in bilateral cases. Other malformations may also be seen (see Figure 8.12.2).

 Microspherophakia: The lens is small and spherical in configuration. It can subluxate into the anterior chamber, causing a secondary glaucoma. Can be isolated or seen in association with Weill-Marchesani syndrome (see Figure 8.12.3).

 Anterior and posterior lenticonus: An anterior or posterior ectasia of the lens surface, posterior occurring more commonly than anterior. Often associated with cataract. Unilateral or bilateral. Anterior lenticonus is associated with Alport syndrome. Posterior lenticonus is usually isolated but may be autosomal dominant. It can also be seen with Alport syndrome.

 Ectopia lentis: See 13.10, Subluxed or Dislocated Crystalline Lens.

 Ectopia lentis et pupillae: Lens displacement associated with pupillary displacement in the opposite direction. Usually not associated with glaucoma.

 Aniridia: Bilateral, near-total absence of the iris. Glaucoma, macular hypoplasia with poor vision, nystagmus, refractive error, and corneal pannus are common. Aniridia is autosomal dominant in two-thirds of patients, a type usually without systemic implications. It occurs sporadically in one-third of cases. May be part of a panocular disorder due to mutations in the master control gene of the eye, PAX6. If PAX6 is deleted as part of a larger chromosomal deletion, it is called WAGR syndrome (Wilms tumor, aniridia, genital abnormalities, retardation). Children with sporadic aniridia have about a 30% chance of Wilms tumor development and require screening, typically with renal ultrasound.

 Sclerocornea: Nonprogressive scleralization of the cornea. Unilateral or bilateral. May be mild and peripheral or severe and diffuse. Associated with severe anterior segment dysgenesis and risk for glaucoma. Often associated with microphthalmia.

 Primary aphakia: Failure of lens development. Usually associated with microphthalmia and severe intraocular dysgenesis including retinal dysplasia and corneal opacity. High risk for glaucoma.

Workup

1. History: Family history of ocular disease? Associated systemic abnormalities?

2. Complete ophthalmic examination, including gonioscopy of the anterior chamber angle and IOP measurement (may require EUA). Fundus photography and A-scan US helpful for serial measurements.

3. Complete physical examination by a primary care physician.

4. In patients with aniridia, obtain chromosomal karyotype with reflex microarray or PAX6 DNA analysis. Until results received, screen with renal ultrasound at diagnosis and no less than every 6 months thereafter until age 7 to 8 years. If deletion involving Wilms tumor gene is found, the frequency of ultrasound should be every 3 months.

Treatment

1. Correct refractive errors and treat amblyopia if present (see 8.7, Amblyopia). Children with unilateral structural abnormalities often have improved visual acuity after amblyopia therapy.

2. Treat glaucoma if present. Beta-blockers, prostaglandin analogs, and carbonic anhydrase inhibitors may be used. Pilocarpine is not effective and is not used in primary therapy (see 9.1, Primary Open Angle Glaucoma). Surgery may be considered initially especially if disease is severe (see 8.11, Congenital/Infantile Glaucoma).

3. Consider cataract extraction if a significant cataract exists and a corneal transplant if a dense corneal opacity exists.

4. Refer to a specialist for genetic counseling and testing, if desired.

5. Systemic abnormalities (e.g., Wilms tumor) are managed by pediatric specialists.

Follow Up

1. Ophthalmic examination every 6 months throughout life, checking for increased IOP and other signs of glaucoma.

2. If amblyopia exists, follow up may need to be more frequent (see 8.7, Amblyopia).

8.13 Congenital Ptosis

Signs

Critical. Droopy eyelid(s).

Other. Amblyopia, strabismus, astigmatism, and telecanthus. In unilateral ptosis, the involved eye may not open for the first several days of life.

Differential Diagnosis

FIGURE 8.13.1 Blepharophimosis.

 Simple congenital ptosis: Either unilateral or bilateral. Present at birth and stable throughout life. May have indistinct or absent upper eyelid crease. The levator muscle is fibrotic resulting in reduced levator function (excursion), less ptosis in downgaze, and often lagophthalmos. May have compensatory brow elevation or chin-up head position. Coexisting motility abnormality if from a third cranial nerve palsy.

 Blepharophimosis syndrome: Blepharophimosis, telecanthus, epicanthal folds, and ptosis. Bilateral and severe. Autosomal dominant with high penetrance (see Figure 8.13.1).

 Marcus Gunn jaw winking: Usually unilateral. Upper eyelid movement with contraction of muscles of mastication, resulting in “winking” while chewing. Upper eyelid crease intact. The ptosis may range from none to severe, but with mastication the levator may lift the eyelid several millimeters above the limbus.

 Acquired ptosis: See 6.1, Ptosis.

 Horner syndrome: Usually unilateral. Typically 2 to 3 mm of ptosis, associated with anisocoria and lower eyelid reverse ptosis (see 10.2, Horner Syndrome). May be congenital (associated with iris heterochromia) or acquired. Acquired forms in children may be related to birth trauma, chest/neck trauma, or metastatic neuroblastoma.

 Pseudoptosis: Dermatochalasis, contralateral proptosis, enophthalmos, hypotropia. See 6.1, Ptosis.

Etiology

Defective function of either the levator or Muller neuromuscular complexes.

Workup

1. History: Age of onset? Duration? Family history? History of trauma or prior surgery? Any crossing of eyes?

2. Visual acuity for each eye separately, with best correction, to evaluate for amblyopia.

3. Refraction checking for anisometropia and astigmatism which is the most common cause for amblyopia with ptosis.

4. Pupillary examination.

5. Ocular motility examination with assessment of head position as well as brow position and action.

6. Measure interpalpebral fissure distance, distance between corneal light reflex and upper eyelid margin, levator function (while manually fixing eyebrow), position and depth of upper eyelid crease. Check for Bell phenomenon and eyelid lag.

7. Slit lamp examination; look for signs of corneal exposure.

8. Dilated fundus examination.

9. If Horner syndrome is suspected, please refer to section 10.2, Horner Syndrome and work with a pediatrician for proper systemic evaluation and workup.

Treatment

1. Observation if degree of ptosis is mild, no evidence of amblyopia, and no abnormal head positioning.

2. Simple congenital ptosis: If levator function is poor, consider a frontalis suspension. If levator function is moderate or normal, consider a levator resection.

3. Blepharophimosis syndrome: Ptosis must be repaired by frontalis suspension because of poor levator function. Telecanthus often gets better with time as the head grows and the bridge of the nose grows forward. If the telecanthus is severe, it may be treated with surgery.

4. Marcus Gunn jaw winking: No treatment if mild. Often the jaw winking improves around school age. Any treatment for ptosis with levator resection will increase the excursion during jaw winking.

Follow Up

1. If observing, patients should be reexamined every 3 to 12 months, depending on severity and age, to monitor for occlusion or anisometropic amblyopia.

2. After surgery, patients should be monitored for undercorrection or overcorrection and recurrence. Exposure keratopathy may be a significant problem after ptosis surgery.

8.14 The Bilaterally Blind Infant

Signs

Searching, roving movements of the eyes starting at about 4 to 8 weeks of age. Poor pupillary constriction to light in infants >31 weeks gestation is a key finding. Inability to fix or follow large, bright objects after 4 months of corrected age.

Etiology With an Abnormal Ocular Examination

 Severe ocular disease or malformation.

 ROP. See 8.2, Retinopathy of Prematurity.

 Dense bilateral cataracts in children >8 weeks of age. See 8.8, Pediatric Cataract.

 Aniridia and other severe anterior segment dysgenesis. See 8.12, Developmental Anterior Segment and Lens Anomalies/Dysgenesis.

 Albinism: Iris transillumination defects and foveal hypoplasia. See 13.8, Albinism.

NOTE: Ocular abnormalities in patients with albinism and aniridia may be subtle and difficult to assess during an office evaluation.

 Optic nerve hypoplasia: Small optic discs can be difficult to detect when bilateral. When present, a “double-ring” sign (a pigmented ring at the inner and outer edge of a peripapillary scleral ring) is diagnostic. If unilateral, may be seen with strabismus, a relative afferent pupillary defect, and unilateral poor fixation instead of searching nystagmus. Usually idiopathic.

NOTE: Bilateral optic nerve hypoplasia is occasionally associated with septo-optic dysplasia (formerly known as de Morsier syndrome). In contrast, unilateral optic nerve hypoplasia is only rarely associated with this syndrome. Septo-optic dysplasia includes midline abnormalities of the brain as well as growth, thyroid, and other trophic hormone deficiencies. Growth retardation, seizures as a result of hypoglycemia, and diabetes insipidus may develop. If bilateral optic nerve hypoplasia is present, obtain an MRI with attention to the hypothalamic- pituitary area. If unilateral optic nerve hypoplasia is present, imaging studies may be considered as clinically relevant.

 Congenital optic atrophy: Rare. Pale, normal-sized optic disc, often associated with mental retardation or cerebral palsy. Normal electroretinogram (ERG). Autosomal recessive or sporadic.

 Shaken baby syndrome: Multilayered retinal hemorrhages often associated with subdural/subarachnoid hemorrhage. See 3.21, Shaken Baby Syndrome.

 Extreme refractive error: Diagnosed on cycloplegic refraction.

 Congenital motor nystagmus: Patients with this condition usually have a mild visual deficit (20/60 or better). Binocular conjugate horizontal nystagmus. More than one type of nystagmus may be present, including jerk, pendular, circular, or elliptical. Patients may adopt a face turn to maximize gaze in the direction of the null point. No associated central nervous system abnormalities exist.

Etiologies With a Normal Ocular Examination

 Leber congenital amaurosis: Rod-cone disorder. May have a normal-appearing fundus initially, but by childhood ocular examination reveals narrowing of retinal blood vessels, optic disc pallor, and pigmentary changes. ERG is markedly abnormal or flat which establishes the diagnosis. Autosomal recessive.

 Congenital stationary night blindness: Visual acuity may be close to normal, nystagmus less common, associated with myopia. ERG is abnormal. Autosomal dominant, recessive, and X-linked forms exist. Often have paradoxical pupillary response (pupillary constriction in dim light after exposure to bright light). Retinal pigmentary abnormalities are seen in some types of congenital stationary night blindness.

 Achromatopsia (rod monochromatism): Vision is in the 20/200 range. Marked photophobia. Pupils react normally to light but may have paradoxical pupillary response. Normal fundus, but photopic ERG is markedly attenuated. Absence of response to flicker light stimulus (25 Hz) is diagnostic. Scotopic ERG is normal.

 Cortical visual impairment: One of the most common causes of visual impairment in children from developed countries. Vision is variable. Although the ocular examination is normal, there is an underlying neurologic deficiency causing decreased visual responses.

 Diffuse cerebral dysfunction: Infants do not respond to sound or touch and are neurologically abnormal. Vision may slowly improve with time.

 Delayed maturation of the visual system: Normal response to sound and touch and neurologically normal. The ERG is normal, and vision usually develops between 4 and 12 months of age. More common in patients with some type of albinism (may have nystagmus at presentation).

Workup

1. History: Premature? Normal development and growth? Maternal infection, diabetes, or drug use during pregnancy? Seizures or other neurologic deficits? Family history of eye disease?

2. Evaluate the infant’s ability to fixate on an object and follow it.

3. Pupillary examination, noting both equality and briskness.

4. Look carefully for nystagmus (see 10.21, Nystagmus).

5. Examination of the anterior segment; check especially for iris transillumination defects.

6. Dilated retinal and optic nerve evaluation.

7. Cycloplegic refraction.

8. ERG and genetic testing if Leber congenital amaurosis or a retinal dystrophy is suspected.

9. Consider a CT scan or MRI of the brain in cases with other focal neurologic signs, seizures, failure to thrive, developmental delay, optic nerve hypoplasia, or neurologically localizing nystagmus (e.g., seesaw, vertical, gaze paretic, vestibular). If optic atrophy, either unilateral or bilateral, is present, obtain an MRI to evaluate for a glioma of the optic nerve or chiasm and craniopharyngioma.

10. Optical coherence tomography may be helpful to further evaluate optic nerve anomalies.

11. Consider eye movement recordings to evaluate the nystagmus wave form, if available.

Treatment

1. Correct refractive errors and treat known or suspected amblyopia.

2. Parental counseling is necessary in all of these conditions with respect to the infant’s visual potential and the likelihood of visual problems in siblings.

3. Referral to educational services for the visually handicapped or blind may be helpful.

4. Provide genetic counseling and testing, if available.

5. If neurologic or endocrine abnormalities are found or suspected, the child should be referred to a pediatrician for appropriate workup and management.