Review questions in ophthalmology

Cornea

KENNETH C. CHERN AND MICHAEL A. SAIDEL

QUESTIONS

1   All of the following are included in the differential diagnosis of this condition shown in Figure 10-1 except:

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FIGURE 10-1

     A)   herpes simplex virus (HSV)

     B)   molluscum contagiosum

     C)   allergic drug reaction

     D)   Stevens–Johnson syndrome

2   Which disease is not caused by Chlamydia trachomatis?

     A)   Ligneous conjunctivitis

     B)   Adult inclusion conjunctivitis

     C)   Lymphogranuloma venereum

     D)   Trachoma

3   Following blunt trauma and the development of a hyphema, all of the following put a patient at higher risk for corneal blood staining except:

     A)   high intraocular pressure (IOP)

     B)   large blood clot

     C)   sickle cell trait or disease

     D)   Fuchs corneal dystrophy

4   Based on the appearance of the corneal infiltrate in Figure 10-2, which laboratory test would be least helpful in aiding in the diagnosis?

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FIGURE 10-2

     A)   Culture on Sabouraud agar

     B)   Calcofluor white stain

     C)   Lowenstein–Jensen agar

     D)   Giemsa stain

5   Which one of the following associations between a microorganism and a useful medium for growth is correct?

     A)   Moraxella—blood agar in 5% to 10% carbon dioxide

     B)   Fungi—Sabouraud dextrose agar with cycloheximide

     C)   Mycobacterium tuberculosis—Loeffler medium

     D)   Haemophilus—blood agar

6   Which one of the following medications is commonly used to treat cases of filamentous fungal keratitis caused by Fusarium spp.?

     A)   Flucytosine

     B)   Natamycin

     C)   Amphotericin B

     D)   Miconazole

7   All of the following are appropriate therapy for primary HSV epithelial keratitis except:

     A)   ganciclovir 0.15% gel

     B)   difluprednate 0.05%

     C)   débridement of corneal lesions

     D)   valacyclovir

8   Which one of the following regarding megalocornea is true?

     A)   Most common inheritance is autosomal dominant

     B)   Associated with progressive corneal enlargement

     C)   Corneal diameter greater than 10 mm

     D)   Associated with Down syndrome

9   Which of the following conditions is not associated with rheumatoid arthritis?

     A)   Limbal follicles

     B)   Peripheral ulcerative keratitis

     C)   Necrotizing scleritis

     D)   Paracentral keratolysis

QUESTIONS 10 and 11 Select the condition(s) associated with the given finding.

10  Can result from mutation at the PAX6 gene:

     A)   Peters anomaly

     B)   Rieger syndrome

     C)   both

     D)   neither

11  Associated with glaucoma:

     A)   Axenfeld syndrome

     B)   Peters anomaly

     C)   both

     D)   neither

12  Which one of the following is not included in the differential diagnosis of blue sclera?

     A)   Hurler syndrome

     B)   Osteogenesis imperfecta

     C)   Turner syndrome

     D)   Marfan syndrome

13  All of the following are associated with conjunctival cicatrization except:

     A)   atopic keratoconjunctivitis

     B)   ocular cicatricial pemphigoid

     C)   Stevens–Johnson syndrome

     D)   superior limbic keratoconjunctivitis

14  Which one of the following is a characteristic of sclerocornea?

     A)   This disease is secondary to an inflammatory process.

     B)   Most cases are unilateral.

     C)   Most affected patients are women.

     D)   This process is nonprogressive.

15  All of the following may be considered part of the iridocorneal endothelial (ICE) syndrome except:

     A)   Chandler syndrome

     B)   essential iris atrophy

     C)   Cogan–Reese syndrome

     D)   posterior embryotoxon

16  Which one of the following is found with Rieger anomaly?

     A)   Autosomal dominant inheritance

     B)   Maxillary hypoplasia

     C)   Hypospadias

     D)   Peg-shaped teeth

17  Which one of the following is not in the differential of a baby whose cornea is shown in Figure 10-3?

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FIGURE 10-3

     A)   Congenital hereditary stromal dystrophy

     B)   Peters anomaly

     C)   Congenital glaucoma

     D)   ICE syndrome

18  Which one of the following represents a choristoma?

     A)   Dermolipoma

     B)   Keratoacanthoma

     C)   Hemangioma

     D)   Lymphangioma

19  Which one of the following would best be used to identify a corneal wound leak?

     A)   Gentian violet

     B)   Rose bengal

     C)   Fluorescein

     D)   Lissamine green

20  Which of the following occurs with the condition pictured in Figure 10-4?

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FIGURE 10-4 Courtesy of Helen K. Wu, MD.

     A)   The steepest meridian of the cornea is adjacent to this lesion.

     B)   These are benign with no malignant potential.

     C)   They can grow rapidly.

     D)   Patients may also have congenital cardiac defects.

21  Which structure is not found in the lesion in Figure 10-4?

     A)   Skin

     B)   Muscle

     C)   Sebaceous glands

     D)   Hair

22  All are true regarding Goldenhar syndrome except:

     A)   Iris colobomas may be present.

     B)   Upper eyelid colobomas may be present.

     C)   Preauricular skin tags may be present.

     D)   It can have an autosomal dominant inheritance.

23  Erythema multiforme major (Stevens–Johnson syndrome) is associated with which of the following etiologic factors?

     A)   Mycoplasma pneumonia

     B)   Sulfonamides

     C)   Coxsackievirus

     D)   All of the above

24  Which one of the following is not associated with enlarged corneal nerves?

     A)   Refsum disease

     B)   Congenital glaucoma

     C)   Ichthyosis

     D)   Multiple endocrine neoplasia (MEN), type I

QUESTIONS 25–27 (FIGS. 10-5A–D)

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FIGURE 10-5

25  Which condition is caused by a virus?

     A)   Figure 10-5A

     B)   Figure 10-5B

     C)   Figure 10-5C

     D)   None of the above

26  Which treatment can be successful for the patient in Figure 10-5D?

     A)   Acyclovir

     B)   Steroid ointment

     C)   Incision

     D)   Doxycycline

27  All of the conditions are associated with the condition pictured in Figure 10-5A except:

     A)   rheumatoid arthritis

     B)   asthma

     C)   hay fever or seasonal allergies

     D)   eczema

28  Which organism is not a usual commensal found on the lids and lashes?

     A)   Moraxella catarrhalis

     B)   Haemophilus influenzae

     C)   Propionibacterium acnes

     D)   Staphylococcus epidermidis

29  Which one of the following statements is correct for the condition in Figure 10-6?

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FIGURE 10-6

     A)   Phthirus pubis is a normal commensal of adult meibomian glands.

     B)   Demodex folliculorum is transmitted by sexual contact.

     C)   Physostigmine acts as a respiratory poison to Phthirus pubis.

     D)   Demodex folliculorum is responsible for collarettes along the base of eyelashes.

30  All of the following medications commonly cause the condition pictured in ­Figure 10-7 except:

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FIGURE 10-7

     A)   atropine

     B)   neomycin

     C)   ketorolac

     D)   apraclonidine

31  All of the following bacteria are commonly known to cause the clinical condition shown in Figure 10-8 except:

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FIGURE 10-8

     A)   Streptococcus

     B)   Staphylococcus

     C)   Nocardia

     D)   Haemophilus

QUESTIONS 32 and 33 A 60-year-old man presents to your office complaining of a “spot” in his right eye, as shown in Figure 10-9.

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FIGURE 10-9

32  Which of the following is not appropriate treatment for this lesion?

     A)   Local excision with wide margins followed by cryotherapy

     B)   Topical prednisolone drops

     C)   Local radiotherapy with a ruthenium-106 plaque sutured to the scleral bed following excision

     D)   Mitomycin C

33  The lesion pictured in Figure 10-9:

     A)   is always benign

     B)   is contagious and easily spread to others

     C)   affects only the superficial epithelium

     D)   can produce keratin

34  Which one of the following statements regarding the conjunctival lesion pictured in Figure 10-10 is true?

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FIGURE 10-10

     A)   Microscopic examination without cellular atypia would confirm the benign nature of the lesion.

     B)   Growth and increased pigmentation can occur during puberty.

     C)   This lesion is confined to the conjunctiva and does not affect the underlying sclera.

     D)   Treatment with cyclosporin drops is needed since steroids are ineffective.

35  Which of the following conditions is thought to have a similar pathophysiology to staphylococcal marginal keratitis?

     A)   Phlectenulosis

     B)   Pterygium

     C)   Pseudogerontoxon

     D)   Pseudomembranes

36  Patients with ocular cicatricial pemphigoid:

     A)   have immunoglobulins bound to the conjunctival basement membrane

     B)   may have increased numbers of goblet cells

     C)   benefit from limbal stem cell transplants

     D)   frequently present with scleritis

QUESTIONS 37–39 A 24-year-old student presents after noticing a localized area of redness in his right eye near his caruncle as shown in Figure 10-11. He has had similar previous lesions that have resolved spontaneously.

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FIGURE 10-11

37  What would the lesion likely show histopathologically?

     A)   Spindle-shaped atypical cells with dark nuclei

     B)   Acanthotic epithelium over fibrovascular cores

     C)   Small caliber vascular channels in collagenase stroma

     D)   Lined nonkeratinizing stratified squamous epithelium

38  Which therapy might be most appropriate at this time?

     A)   Observation

     B)   Simple excision

     C)   Photocoagulation

     D)   Excision with frozen section controls

39  Which virus has been implicated in causing this lesion?

     A)   Epstein–Barr virus

     B)   Human papilloma virus

     C)   HSV

     D)   Molluscum contagiosum virus

40  What is the most common malignant epithelial tumor of the conjunctiva?

     A)   Basal cell carcinoma

     B)   Squamous cell carcinoma

     C)   Malignant melanoma

     D)   Squamous papilloma

41  Regarding conjunctival intraepithelial neoplasia, which one of the following is true?

     A)   It rarely occurs in the interpalpebral zone.

     B)   Treatment is by enucleation.

     C)   Abnormal vascularization is rare.

     D)   The entire thickness of the epithelium may be involved.

42  Which one of the following is not a cause of secondary acquired conjunctival melanosis?

     A)   Pregnancy

     B)   Topical epinephrine drops

     C)   Addison disease

     D)   Scleritis

QUESTIONS 43–46 (Figs. 10-12 to 10-15)

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FIGURE 10-12

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FIGURE 10-13

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FIGURE 10-14

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FIGURE 10-15

     A)   Figure 10-12

     B)   Figure 10-13

     C)   Figure 10-14

     D)   Figure 10-15

43  Which has the lowest neoplastic potential?

44  Which often occurs bilaterally?

45  Which may enlarge during adolescence or with pregnancy?

46  Which requires a systemic disease workup?

QUESTIONS 47–49 A 47-year-old farmer presents with the lesion pictured in Figure 10-16. He states it has been present for at least 2 years, and it has been gradually increasing in size.

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FIGURE 10-16

47  This lesion may lead to all of the following except:

     A)   an adjacent dellen

     B)   flattening in the involved meridian with change in central astigmatism

     C)   destruction of Bowman layer

     D)   distant metastasis

48  Possible treatment options, if this were a recurrent lesion, would likely include all of the following except:

     A)   simple excision, leaving bare sclera

     B)   excision with amniotic membrane graft

     C)   excision with mitomycin C application and conjunctival autograft

     D)   excision with conjunctival autograft

49  Which is correct regarding the lesion pictured in Figure 10-16?

     A)   Histopathology shows fibrovascular ingrowth just beneath Bowman layer.

     B)   A pigmented iron line (Ferry line) is found at the leading corneal edge of the lesion.

     C)   Prolonged actinic exposure is a risk factor.

     D)   Recurrence after treatment is rare.

QUESTIONS 50 and 51

50  Which one of the following regarding the condition shown in Figure 10-17 is true?

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FIGURE 10-17

     A)   Corneal sensation is reduced.

     B)   Resection of the adjacent conjunctiva may be indicated.

     C)   Treatment with a silver nitrate stick is beneficial.

     D)   A Fox shield at bedtime is helpful.

51  Which systemic finding might be found in association with this condition?

     A)   Increased urine catecholamines

     B)   Macular skin rash

     C)   Hyperextensible joints

     D)   Decreased thyroid-stimulating hormone levels

52  Which of the following is appropriate treatment of the condition shown in Figure 10-18?

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FIGURE 10-18

     A)   Topical moxifloxacin

     B)   Oral doxycycline

     C)   Change from hard contact lenses to soft contact lenses

     D)   Topical mast cell stabilizers or corticosteroid drops

QUESTIONS 53–55 Corneal staining patterns in Figure 10-19. The cornea is stained with fluorescein or a vital dye.

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FIGURE 10-19

53  Which pattern can be found in a patient with thyroid eye disease and proptosis?

     A)   Figure 10-19M

     B)   Figure 10-19D

     C)   Figure 10-19N

     D)   Figure 10-19E

54  Which pattern is most typical of Thygeson keratopathy?

     A)   Figure 10-19K

     B)   Figure 10-19E

     C)   Figure 10-19N

     D)   Figure 10-19B

55  Figure 10-19J corresponds to which condition below?

     A)   Superior limbic keratitis

     B)   Epidemic keratoconjunctivitis (EKC)

     C)   Rosacea keratoconjunctivitis

     D)   Exposure keratopathy

QUESTIONS 56 and 57

56  All of the following drugs can cause a corneal appearance as in Figure 10-20 except:

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FIGURE 10-20

     A)   amiodarone

     B)   lithium

     C)   chloroquine

     D)   indomethacin

57  Which metabolic disease can manifest as shown in Figure 10-20?

     A)   Fabry disease

     B)   Tay–Sachs disease

     C)   Alport syndrome

     D)   Refsum disease

58  Which one of the following is most accurate regarding a 54-year-old man with cystinosis?

     A)   All other siblings would have similar findings.

     B)   He is likely of short stature and has renal dysfunction.

     C)   He is unlikely to develop epithelial erosions.

     D)   The cystine deposits begin centrally within the anterior stroma and progress to involve the entire cornea.

QUESTIONS 59 and 60 A 15-year-old girl presents with muscle tremors and a brownish ring near the limbus shown in Figure 10-21.

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FIGURE 10-21

59  The deposits shown in the photograph are localized to which layer of the cornea?

     A)   Epithelium

     B)   Bowman layer

     C)   Posterior stroma

     D)   Descemet membrane

60  Which one of the following statements regarding this disease is true?

     A)   It is an isolated, nonhereditary disease.

     B)   The corneal findings can be used to monitor therapy.

     C)   It is caused by a defect in the kidneys.

     D)   The corneal findings are pathognomonic for this patient’s disease.

QUESTIONS 61 and 62

61  The findings in Figure 10-22 can be found in which condition?

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FIGURE 10-22

     A)   Adult inclusion conjunctivitis

     B)   Vernal keratoconjunctivitis

     C)   Trachoma

     D)   Staphylococcal marginal keratitis

62  All of the following ocular findings may accompany this condition except:

     A)   superior corneal pannus

     B)   conjunctival scarring

     C)   superior conjunctival follicles

     D)   leukoplakia

QUESTIONS 63 and 64

63  Which one of the following statements regarding the disease process shown in Figure 10-23 is false?

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FIGURE 10-23

     A)   The deposits consist of calcium hydroxyapatite and are found mainly in Bowman layer.

     B)   This patient may have deposition of copper in the liver, kidneys, and brain.

     C)   Patients with this disease may be on long-term topical steroids.

     D)   This disease may be associated with chronic mercurial exposure.

64  Which topical agent might be used to treat this condition?

     A)   Ethylenediaminetetraacetic acid (EDTA)

     B)   Penicillamine

     C)   Corticosteroids

     D)   Acetylcysteine

65  Which one of the following statements regarding spheroidal degeneration of the cornea is false?

     A)   It is usually bilateral.

     B)   Pathologically, it appears as lipid deposition in the cornea.

     C)   Patients usually remain asymptomatic.

     D)   Actinic exposure is implicated in the pathogenesis of spheroidal degeneration.

66  Which one of the following is the most accurate statement regarding the condition shown in the Figure 10-24?

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FIGURE 10-24

     A)   It is often associated with a systemic autoimmune disease.

     B)   With-the-rule astigmatism may be induced.

     C)   Thinning is more apparent than real.

     D)   Epithelium remains intact.

67  Which one of the following statements regarding the clinical condition found in this 73-year-old woman (Fig. 10-25) is true?

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FIGURE 10-25

     A)   Biopsy of the adjacent conjunctiva may show increased plasma cells.

     B)   Corneal perforation will occur rapidly.

     C)   Systemic immunosuppressives will be necessary.

     D)   It is a painless, slowly progressive process.

68  Which is true of pellucid marginal degeneration?

     A)   Decreased vision results from lipid deposition.

     B)   Protrusion of the cornea is at the point of maximal thinning.

     C)   This is a bilateral condition.

     D)   Best surgically treated with PRK.

QUESTIONS 69–71

69  Which one of the following is not characteristic of the condition shown on corneal topography (Fig. 10-26)?

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FIGURE 10-26

     A)   Apical scarring

     B)   Scissoring of the red reflex on retinoscopy

     C)   Spontaneous perforation

     D)   Fleischer ring

70  All of the following are accepted treatment measures for visual rehabilitation in this condition except:

     A)   riboflavin and corneal cross-linking

     B)   hard contact lens fitting

     C)   penetrating keratoplasty

     D)   photorefractive keratectomy (PRK)

71  This same patient comes back with a dramatic decrease in vision and this corneal appearance (Fig. 10-27). What is the best initial treatment?

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FIGURE 10-27

     A)   Hypertonic saline

     B)   Antibiotic drops

     C)   Corneal transplantation

     D)   Descemet stripping endothelial keratoplasty (DSEK)

QUESTIONS 72 TO 73 PERTAIN TO THE FOLLOWING FIGURE (FIG. 10-28). A 25-year-old woman presents with 2 days of eyelid redness, swelling, and discomfort. She has been using cold compresses with no improvement.

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FIGURE 10-28

72  What diagnostic tests, if any, would be helpful in confirming the diagnosis?

     A)   Gram stain looking for diplococci

     B)   Adenovirus DFA

     C)   Conjunctival biopsy looking for eosinophils

     D)   No tests needed, diagnosis based on clinical appearance

73  What other findings would be commonly seen with this eyelid appearance?

     A)   Conjunctival membranes

     B)   Epithelial dendrites

     C)   Shield ulcer

     D)   Hypopyon

74  Which one of the following is true regarding congenital hereditary endothelial dystrophy?

     A)   Nystagmus is absent in the recessive form of the disease.

     B)   There are usually associated systemic abnormalities.

     C)   The recessive form is nonprogressive, whereas the dominantly inherited form is slowly progressive.

     D)   Corneal clouding is present at birth in both forms of the disease.

75  Which one of the following concerning congenital hereditary stromal dystrophy is false?

     A)   Autosomal dominant inheritance

     B)   Symptoms of pain, tearing and photophobia

     C)   Central anterior stromal flaky, feathery opacity

     D)   Cornea of normal thickness

76  Of the corneal dystrophies below, which is the most common?

     A)   Lattice stromal dystrophy

     B)   Macular stromal dystrophy

     C)   Granular stromal dystrophy

     D)   Meesmann dystrophy

QUESTIONS 76 and 77 A 24-year-old woman presents with ocular irritation, foreign body sensation, decreased vision in the right eye, and the findings shown in Figure 10-29.

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FIGURE 10-29

77  What would histopathologic examination of the corneal specimen show?

     A)   Amyloid deposits

     B)   Cholesterol and neutral fats

     C)   Acid mucopolysaccharides

     D)   Hyaline

78  Which one of the following statements regarding the disease shown in Figure 10-29 is true?

     A)   Both of the patient’s siblings are likely affected.

     B)   The disease is caused by a defect in the synthesis of keratan sulfate.

     C)   Epithelial erosions are a frequent, recurring problem.

     D)   In the majority of cases, only the central cornea is affected.

QUESTIONS 79 and 80 A 27-year-old woman presents with foreign body sensation in her eye and has the findings shown in Figure 10-30.

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FIGURE 10-30

79  Which of the following is true?

     A)   Initially, deposits are concentrated in the periphery.

     B)   The corneal findings are best shown by specular reflection.

     C)   The deposits are found in the posterior stroma.

     D)   Skin findings and nerve palsies are manifestations of systemic involvement.

80  All of the following stains will highlight the deposits seen in this disease except:

     A)   thioflavin T

     B)   Congo red

     C)   alcian blue

     D)   crystal violet

81  Each of the following statements regarding granular corneal dystrophy is true except:

     A)   the corneal findings precede symptoms by several years.

     B)   the intervening cornea is characteristically clear between lesions.

     C)   recurrent erosions are common.

     D)   the deposits consist of hyaline, which stains with Masson trichrome.

QUESTIONS 82–86 Match the condition(s) with the associated finding.

     A)   Figure 10-31

     B)   Figure 10-32

     C)   Both

     D)   Neither

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FIGURE 10-31

images

FIGURE 10-32

82  Progressive disorder?

83  Recurrence of disease in grafts?

84  Autosomal recessive inheritance?

85  Epithelial erosions occur frequently?

86  Vision severely affected in most cases?

QUESTIONS 87 and 88 A 34-year-old man presents with a report of decreased visual acuity in both eyes. He has had many episodes of pain and redness that last several days. His father has the same condition. His right eye is shown in Figure 10-33.

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FIGURE 10-33

87  Which one of the following statements regarding these findings is true?

     A)   The opacities are at the level of the stroma.

     B)   The lesions are among the most common to recur after penetrating keratoplasty.

     C)   This condition is not progressive.

     D)   Recurrent erosions are rare.

88  Histopathology would show:

     A)   disruption and absence of Bowman layer

     B)   “peculiar substance” replacing Bowman layer

     C)   birefringence and dichroism

     D)   staining of these lesions with Oil Red O

89  All of the following statements regarding the condition pictured in Figure 10-34 are true except:

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FIGURE 10-34

     A)   It is the most common anterior corneal dystrophy.

     B)   It is the most common dystrophic cause of recurrent corneal erosions.

     C)   It occurs as a unilateral disease.

     D)   Symptoms are more common after age 30.

QUESTIONS 90–92 A 72-year-old woman presents with blurred vision in both eyes that is worse upon awakening and clears somewhat throughout the day. She denies eye pain. Both eyes have a similar clinical appearance, which is shown in Figure 10-35.

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FIGURE 10-35

90  Which of the following might be found in this disease?

     A)   Multilaminar Descemet membrane studded with excrescences

     B)   Heavy pigment deposition in the trabecular meshwork

     C)   Breaks in Descemet membrane

     D)   Deposition of proteoglycans in the corneal stroma

91  Which diagnostic modality provides the most definitive diagnosis?

     A)   Pachymetry

     B)   Corneal topography

     C)   Specular microscopy

     D)   Corneal biopsy

92  The statement most correct about treatment and prognosis is:

     A)   Bandage contact lens may be used to treat ruptured bullae.

     B)   Hypertonic drops and lowering of IOP are long-term solutions for corneal edema.

     C)   Penetrating keratoplasty carries a poor prognosis.

     D)   Anterior stromal puncture may be used to treat ruptured bullae outside the visual axis.

93  A patient undergoes cataract surgery and has the appearance shown in ­Figure 10-36 the day after surgery. All of the following are possible causes for this except:

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FIGURE 10-36

     A)   retained viscoelastic material within the anterior chamber

     B)   endothelial toxicity from intracameral antibiotics

     C)   anterior chamber phacoemulsification of a dense nucleus

     D)   descemet detachment

94  All of the following corneal dystrophies are linked to chromosome 5q31 except:

     A)   Meesmann dystrophy

     B)   lattice dystrophy

     C)   Reis–Buckler dystrophy

     D)   Avellino dystrophy

95  Which is not true regarding the condition shown in Figure 10-37?

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FIGURE 10-37

     A)   It is associated with trachoma, anterior basement membrane dystrophy, and severe rosacea.

     B)   The lesions are most frequently located in the midperipheral cornea.

     C)   Nodular collagenous material is present between the epithelium and Bowman layer.

     D)   Best treated by excimer laser phototherapeutic keratectomy

96  A 65-year-old woman had cataract surgery. She comes back for her 1-week visit; her eye is shown in Figure 10-38. What should be done to help this resolve?

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FIGURE 10-38

     A)   Start her on fortified antibiotic drops.

     B)   Increase the frequency of her topical steroid drop.

     C)   Discontinue her fluoroquinolone drop.

     D)   Scrape lesion and look for hyphae on microscopy.

QUESTION 97–99 A 42-year-old man presents with photophobia and tearing. Both eyes have a similar appearance. His right eye is shown in Figure 10-39.

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FIGURE 10-39

97  All the following are true except:

     A)   corneal sensation is reduced.

     B)   it may be treated with topical cyclosporine.

     C)   there is typically a chronic recurrent course.

     D)   it is associated with histocompatibility antigen HLA-DR3.

98  A 32-year-old woman presents 1 week after experiencing redness, discharge, and itching in both her eyes with a concurrent upper respiratory infection with decreased vision. Her right eye is shown in Figure 10-40. All are possible treatments except:

images

FIGURE 10-40

     A)   cool compresses

     B)   topical steroid therapy

     C)   débridement

     D)   lubrication

99  Figure 10-41 shows the inferior fornix of the same woman. The woman should be instructed to do which of the following?

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FIGURE 10-41

     A)   Use topical ciprofloxacin.

     B)   Stay off work for 5 days.

     C)   Frequently clean hands with alcohol-based sanitizer.

     D)   Do not share towels or pillows.

QUESTIONS 100–102 A 37-year-old woman presents with 2 days of redness, tearing, and the sensation of grittiness in her eye. Her cornea is pictured in Figure 10-42.

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FIGURE 10-42

100 What organism is associated with this condition?

     A)   Herpes simplex

     B)   Propionibacterium acnes

     C)   S. aureus

     D)   Hepatitis C

101 What accompanying condition might this patient have?

     A)   Blepharitis

     B)   Lagophthalmos

     C)   Skin rash

     D)   Arthritis

102 Which treatment would rapidly resolve this condition?

     A)   Prednisolone acetate

     B)   Hypertonic sodium chloride

     C)   Trifluridine

     D)   Gatifloxacin

103 Which one of the following organisms is capable of traversing intact corneal epithelium and establishing bacterial keratitis as shown in Figure 10-43?

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FIGURE 10-43

     A)   S. aureus

     B)   S. epidermidis

     C)   Pseudomonas aeruginosa

     D)   Haemophilus influenzae

QUESTIONS 104 and 105 A 23-year-old medical student underwent PRK for mild myopia. He did well during the procedure but postoperatively complained of severe pain. At 3 days postoperatively, the epithelial defect had not healed and appeared unchanged in size with ragged borders. One week postoperatively, he presented as shown in Figure 10-44.

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FIGURE 10-44

104 Which one of the following is least likely in the differential diagnosis?

     A)   Bacterial keratitis

     B)   Fungal keratitis

     C)   Toxic medicamentosa

     D)   Disciform keratitis

105 All of the following are important initial diagnostic steps to perform except:

     A)   corneal scraping for smear and culture

     B)   questioning about use of topical medications

     C)   corneal biopsy

     D)   testing corneal sensation

QUESTIONS 106 and 107 A 40-year-old woman had refractive surgery 1 year ago. She presents as shown in Figure 10-45.

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FIGURE 10-45

106 Which of the following most accurately describes the picture?

     A)   The patient had PRK.

     B)   The grayish areas are epithelial cells and basement membrane in the stroma.

     C)   The patient will require surgical treatment.

     D)   The grayish areas are infectious.

107 Treatment options include:

     A)   topical antibiotics

     B)   topical steroids

     C)   surface ablation

     D)   lifting the flap and scraping

QUESTIONS 108–112

     A)   Herpes simplex keratitis

     B)   Herpes zoster keratitis

     C)   Both

     D)   Neither

108 Corneal anesthesia?

109 Active viral replication in epithelial lesions?

110 Sectoral iris atrophy?

111 Ulcerated epithelial lesion?

112 Vesicular skin rash?

113 Which one of the following regarding Schnyder crystalline corneal dystrophy is incorrect?

     A)   Opacities recur in corneal transplants.

     B)   It is composed of cholesterol crystals.

     C)   There are associated lipid arcus.

     D)   It is an indicator of elevation of systemic lipid levels.

QUESTIONS 114–116 A 32-year-old man presents with a 3-day history of redness and photophobia of his right eye. He vaguely remembers having redness of this same eye 6 months ago that resolved spontaneously. He denies trauma. His appearance at the slit lamp is shown in Figure 10-46.

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FIGURE 10-46

114 Which one of the following is most accurate about this condition?

     A)   His previous episode of ocular redness is irrelevant.

     B)   Edges of these lesions stain with rose bengal.

     C)   Histopathology would show intracytoplasmic inclusions.

     D)   Treatment is necessary for resolution.

115 The same patient presents 1 year later as seen in Figure 10-47. Which of the following can be said of the patient?

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FIGURE 10-47

     A)   The lesion is active and requires treatment with topical steroids and systemic antivirals.

     B)   This patient is an ideal candidate for PRK.

     C)   The corneal opacity is secondary to toxicity.

     D)   The corneal opacity is beneath the epithelium.

116 This same patient presents 2 years later as shown in Figure 10-48. All of the following statements regarding treatment are true except:

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FIGURE 10-48

     A)   Oral acyclovir will expedite recovery.

     B)   The lowest effective dose of a topical anti-inflammatory (steroid) should be used.

     C)   Topical antivirals should be used concomitantly with topical steroids.

     D)   Patients with peripheral lesions and mild inflammation who maintain good visual acuity may be observed.

QUESTIONS 117 and 118 A 17-year-old contact lens wearer developed pain, redness, photophobia, and decreased visual acuity in her right eye 2 days ago. She states that she cares for and cleans her lenses meticulously and wears them no more than 8 hours a day. She does admit to being on a camping trip for 3 days about 2 weeks ago. Her left eye is pictured in Figure 10-49.

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FIGURE 10-49

117 Which one of the following regarding this condition is true?

     A)   Patients complain of a dull, aching pain.

     B)   Enlarged corneal nerves are pathognomonic.

     C)   These organisms grow best in thioglycolate broth.

     D)   Simple mechanical débridement may be curative when confined to the corneal epithelium.

118 Corneal biopsy may be expected to show:

     A)   gram-negative rods

     B)   double-walled cysts

     C)   acid-fast pleomorphic rods

     D)   branching hyphae

119 A 25-year-old soft contact lens wearer presents with severe pain in her right eye after wearing her daily disposable contact lens overnight for 1 week. Pictured is her right eye (Fig. 10-50). The least appropriate therapy is:

images

FIGURE 10-50

     A)   topical moxifloxacin

     B)   topical cefazolin

     C)   topical gatifloxacin

     D)   fortified topical vancomycin and tobramycin

120 Which is the most common cause of bilateral interstitial keratitis?

     A)   Congenital syphilis

     B)   Tuberculosis

     C)   Cogan syndrome

     D)   Acquired syphilis

121 Which one of the following is a cause for the condition pictured in Figure 10-51?

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FIGURE 10-51

     A)   Sjögren syndrome

     B)   Cranial nerve V paralysis

     C)   Chemical splash

     D)   Bell palsy

122 Which one of the following treatments would be most effective for this condition?

     A)   Tarsorrhaphy

     B)   Rigid gas permeable contact lens

     C)   Penetrating keratoplasty

     D)   Anterior stromal micropuncture

QUESTIONS 123 and 124 A 72-year-old woman presents to your office with a report of red eyes and foreign body sensation for several months. She also recently notes the onset of dysphagia. Her slit-lamp appearance is shown (Fig. 10-52).

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FIGURE 10-52

123 All of the following statements are true except:

     A)   She should be asked about use of topical medications.

     B)   Conjunctival scrapings may reveal eosinophils.

     C)   Corneal scarring and vascularization are successfully treated with penetrating keratoplasty.

     D)   Immunoglobulins are deposited along the conjunctival basement membrane.

124 Which treatment would be most effective for this condition?

     A)   Dapsone

     B)   Topical steroid drops

     C)   Lysis of membranes

     D)   Topical cyclosporine

125 Which one of the following is not a cause of cicatrizing conjunctivitis?

     A)   Trachoma

     B)   Chemical burns

     C)   Stevens–Johnson syndrome

     D)   Staphylococcal hypersensitivity

126 All of these conditions may cause the corneal picture in Figure 10-53 except:

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FIGURE 10-53

     A)   prolonged patching

     B)   dry eyes

     C)   superior limbic keratoconjunctivitis

     D)   floppy eyelid syndrome

127 This cornea has markedly decreased sensation (Fig. 10-54). The patient denies a history of trauma. Which one of the following statements is least correct?

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FIGURE 10-54

     A)   This condition may be surgically induced.

     B)   Long-term steroids are helpful.

     C)   Patching may be beneficial.

     D)   Tarsorrhaphy is often helpful in refractory cases.

QUESTIONS 128 and 129 A healthy 18-year-old black man presents with a total hyphema after being struck in the right eye with a tennis ball. Visual acuity is hand motions, and the IOP is normal (Fig. 10-55).

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FIGURE 10-55

128 Which one of the following would be appropriate in the management of this patient?

     A)   Topical steroids and a cycloplegic

     B)   Bed rest, elevation of the head of the bed, bilateral patches

     C)   Oral aminocaproic acid

     D)   All of the above

129 If this patient’s IOP had been elevated and a small amount of corneal blood staining resulted, what would be the most appropriate next step?

     A)   Anterior chamber washout

     B)   Topical carbonic anhydrase inhibitor

     C)   Continued observation

     D)   Injection of tissue plasminogen activator into the anterior chamber

130 Superficial phototherapeutic keratectomy is indicated in treating symptoms in the following conditions except:

     A)   Reis–Buckler dystrophy

     B)   granular dystrophy

     C)   epithelial basement membrane dystrophy

     D)   fleck dystrophy

QUESTIONS 131 and 132 A 28-year-old man was splashed in the eyes with a chemical solvent while at work. He noted immediate pain and decreased vision despite aggressive irrigation. His right eye is pictured in Figure 10-56.

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FIGURE 10-56

131 Which one of the following statements concerning this injury is true?

     A)   Acid burns cause loss of ground substance and collagen swelling.

     B)   The worst damage from alkali burns occurs immediately.

     C)   Burns at the limbus and burns at the palpebral conjunctiva have a similar prognosis.

     D)   Severe uveitis and glaucoma may occur.

132 All of the following statements concerning treatment are true except:

     A)   Irrigation should be started immediately and continued in the emergency room.

     B)   Débridement of necrotic conjunctiva should be performed.

     C)   Topical steroids are used long-term to decrease the inflammatory response.

     D)   Prognosis for penetrating keratoplasty is best after the inflammatory process has quieted.

QUESTIONS 133 and 134 A healthy 20-year-old man presents with sudden onset of tearing, redness, and irritation of his right eye (Fig. 10-57). He does not complain of floaters, blurred vision, or pain with eye movement. Visual acuity is 20/20 in both eyes.

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FIGURE 10-57

133 Which one of the following would be least helpful in your diagnosis?

     A)   Recent history of upper respiratory tract infection

     B)   Examination under natural light

     C)   Pupillary exam

     D)   Examination of conjunctiva under slit lamp

134 The dilated vessels in Figure 10-57 were salmon pink, moved freely with the conjunctiva, and blanched with the application of topical epinephrine. Which one of the following would be least appropriate therapy?

     A)   Observation

     B)   Topical steroids

     C)   Topical antibiotics

     D)   Oral nonsteroidal agents

135 Which one of the following is the most destructive form of scleritis?

     A)   Diffuse anterior scleritis

     B)   Necrotizing scleritis with inflammation

     C)   Nodular anterior scleritis

     D)   Scleromalacia perforans

136 All of the following have been associated with scleritis except:

     A)   gout

     B)   tuberculosis

     C)   leprosy

     D)   Behçet disease

137 All of the following are acceptable therapies for scleritis except:

     A)   posterior sub-Tenon steroid injection

     B)   oral nonsteroidal anti-inflammatory agents (NSAIDs)

     C)   topical cyclosporine

     D)   systemic steroids

138 Which of the following is not associated with an abnormality of limbal stem cell proliferation?

     A)   Shield ulcer

     B)   Stevens–Johnson Syndrome

     C)   Aniridia

     D)   Chemical injury

139 Reduction of positive vitreous pressure during ocular surgery may be accomplished by all of the following except:

     A)   aspiration of liquid vitreous through the pars plana

     B)   adjustment of a poorly fitting lid speculum

     C)   IV mannitol

     D)   hypoventilation during general anesthesia

140 You obtain a cornea for an elective penetrating keratoplasty and you notice that the color of the storage medium is yellow–orange instead of the usual pink. What does this indicate?

     A)   Decrease in antibiotic levels

     B)   Loss of epithelium

     C)   A cornea over 3 days old

     D)   Possible microbial contamination

141 Of the following, what is currently the most common indication for keratoplasty in adults?

     A)   Granular corneal dystrophy

     B)   Aphakic bullous keratopathy

     C)   Pseudophakic bullous keratopathy (PBK)

     D)   Herpes simplex keratitis

142 Of the following, which is the most frequent indication for penetrating keratoplasty in children?

     A)   Sclerocornea

     B)   Interstitial keratitis

     C)   Peters anomaly

     D)   Bacterial keratitis

143 Special considerations when performing penetrating keratoplasty in children include all of the following except:

     A)   oversized grafts

     B)   scleral support during surgery

     C)   early removal of sutures postoperatively

     D)   frequent postoperative follow-up

144 Postoperative complications in pediatric penetrating keratoplasty include all of the following except:

     A)   glaucoma

     B)   amblyopia

     C)   slow or delayed healing

     D)   graft rejection

145 Overall, approximately what percentage of corneal grafts are clear greater than 1 year postoperatively?

     A)   90%

     B)   65%

     C)   50%

     D)   40%

146 Approximately what percentage of corneal grafts performed for HSV keratitis remains clear greater than 1 year postoperatively?

     A)   90%

     B)   65%

     C)   50%

     D)   40%

147 Overall, the risk of an endothelial graft rejection episode is:

     A)   1%

     B)   5%

     C)   20%

     D)   40%

148 According to the Collaborative Corneal Transplant Study:

     A)   human leukocyte antigens (HLA) tissue matching was clearly advantageous.

     B)   HLA tissue matching was considered cost-effective.

     C)   ABO blood type incompatibility was shown to be a possible risk factor.

     D)   peripheral corneal vascularization was not a significant risk factor.

149 Poor candidates for refractive surgery may include:

     A)   pathologic (posterior segment) myopia

     B)   keratoconus

     C)   history of HSV keratitis

     D)   all of the above

150 Most rigid gas-permeable contact lens wearers should discontinue use of their lenses at least how many days before a refractive surgery evaluation?

     A)   7 days

     B)   21 days

     C)   30 days

     D)   60 days

151 The patient in Figure 10-58 is most likely to undergo which of the following?

images

FIGURE 10-58

     A)   A trend toward hyperopia

     B)   Worsening a corneal dystrophy

     C)   Recurrent episodes of eye pain

     D)   Epithelial downgrowth

152 Concerning the patient in Figure 10-58, after what number of incisions does the dioptric effect per incision decrease significantly?

     A)   Four incisions

     B)   Eight incisions

     C)   16 incisions

     D)   32 incisions

153 Concerning astigmatic keratotomy for naturally occurring astigmatism, arcuate incisions greater than how many degrees are relatively contraindicated?

     A)   60°

     B)   90°

     C)   120°

     D)   130°

154 Which of the following was a conclusion of the Collaborative Corneal Transplant Study?

     A)   HLA-A, HLA-B, and HLA-DR matching the donor and recipient had no effect on overall graft survival.

     B)   Grafts with running sutures had earlier improvement of vision compared to grafts with interrupted sutures.

     C)   Matching donor and recipient age is beneficial to long-term graft survival.

     D)   ABO blood type matching does not reduce the risk of graft rejection.

155 Which of these quadrants of the paracentral cornea is most often the thinnest, based on intraoperative pachymetry in radial keratotomy patients?

     A)   Nasal

     B)   Inferior

     C)   Superior

     D)   Temporal

156 The patient in Figure 10-59 is most likely to have which of the following?

images

FIGURE 10-59

     A)   Endothelial dystrophy

     B)   Peripheral anterior synechia

     C)   Tram-track appearance

     D)   Bilateral guttata

157 The patient in Figure 10-60 complains of redness and decreased vision. Which of the following can be said of the patient?

images

FIGURE 10-60

     A)   She has had endothelial keratoplasty.

     B)   She has endothelial rejection.

     C)   The patient has a viral keratitis.

     D)   The patient has keratoconus.

158 Figure 10-61 shows a postoperative day 1 patient. Which best describes the photo of this patient?

images

FIGURE 10-61

     A)   The patient has a diagnosis of macular corneal dystrophy.

     B)   After the surgery, the patient kept a head-down position for the first 24 hours.

     C)   Clear corneal incisions have lower induced astigmatism than scleral tunnels.

     D)   A hyperopic shift is expected.

QUESTIONS 159 and 160 A 45-year-old woman (Fig. 10-62) presents complaining of progressive vision loss. The patient is healthy but recently underwent bariatric surgery.

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FIGURE 10-62

159 Which of the following tests would be most appropriate for this patient?

     A)   Serum vitamin A levels

     B)   Rheumatoid factor

     C)   Thyroid levels

     D)   Antinuclear antibody titer

160 The patient in Figure 10-62 was found to have a Pseudomonas corneal ulcer. She presented two weeks later as seen in Figure 10-63. Proper care of the patient includes which of the following?

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FIGURE 10-63

     A)   Bandage contact lens

     B)   Topical NSAIDs

     C)   Tectonic graft

     D)   Topical antivirals

161 The patient in Figure 10-64 presents complaining of a worm-like mass in her eye. The most appropriate course of action would be:

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FIGURE 10-64

     A)   excisional biopsy

     B)   helminthic work up

     C)   grasping the lesion with forceps and using cryotherapy

     D)   reassurance and observation

162 Figure 10-65 is a photograph of a patient supine on the operating table. The patient would be expected to develop which of the following?

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FIGURE 10-65

     A)   Cataract

     B)   Band keratopathy

     C)   Transplant detachment

     D)   Disciform keratitis

ANSWERS

1   D) Stevens–Johnson syndrome

     This patient has a follicular conjunctivitis. Follicles are small avascular mounds of lymphocytes and plasma cells. Papillae are formed by edema and leakage of fluid from telangiectatic vessels. The differential diagnosis of a follicular conjunctivitis includes EKC, HSV, chlamydia, molluscum contagiosum, as well as topical drug reactions (type IV hypersensitivity to medications such as brimonidine or neomycin).

     Stevens–Johnson syndrome is a systemic autoimmune disease that causes sloughing of the mucous membranes (including the conjunctiva). This can be a reaction to medication from sulfonamides, Dilantin, and others. In milder cases, patients may present with a papillary conjunctivitis.

2   A) Ligneous conjunctivitis

     Chlamydia trachomatis causes a variety of ocular and systemic diseases. Trachoma caused by C. trachomatis serotypes A, B, Ba, and C is considered to be the leading cause of blindness worldwide. In its early stages, trachoma presents as a follicular conjunctivitis. Severe inflammation can lead to tarsal scarring (which may lead to trichiasis and entropion), corneal scarring, and blindness. Chlamydia trachomatis serotypes D to K are associated with adult inclusion conjunctivitis, which can manifest as a chronic follicular conjunctivitis. Lymphogranuloma venereum is a result of infection by serotypes L1, L2, or L3. This disease does not usually affect the eyes.

     Ligneous conjunctivitis can result from any ocular infection that produces such a vigorous response that there is exudation of fibrin and formation of a hard, woody membrane. The etiology of ligneous is not known, but an inherited plasminogen deficiency has been suggested.

3   C) Sickle cell trait or disease

     Corneal blood staining usually occurs following trauma where a large hyphema develops within the eye. High pressure, long duration, and endothelial dysfunction allow blood breakdown products (hemoglobin, hemosiderin) to migrate into the corneal stroma resulting in the yellowish-brown discoloration. Sickle cell trait or disease, in and of itself, is not a risk factor for corneal blood staining, but in these patients, blood clots may linger in the anterior chamber longer and cause high pressures. In cases of large hyphema, lowering IOP and removal or evacuation of the blood clot from the anterior chamber may be needed to prevent this complication. Once blood staining is present, it can take years for the material to leach out of the cornea, if at all.

4   C) Löwenstein–Jensen agar

     This is a typical presentation of a fungal keratitis. Löwenstein–Jensen agar is used to help identify mycobacteria. Sabouraud agar is used to help identify fungi. Calcofluor white binds to the cell walls of fungi and Acanthamoeba, enhancing their visibility under a fluorescent microscope. Giemsa stains are useful for identifying fungi, bacteria, and intracytoplasmic inclusions in chlamydial infections by light microscopy.

5   A) Moraxella—blood agar in 5% to 10% carbon dioxide

     Moraxella is a slow-growing, aerobic bacterium that grows best in the conditions described at 37°C. It is classically known for causing angular blepharitis, although less commonly than does StaphylococcusMoraxella can also cause conjunctivitis and keratitis.

     Cultures for ocular fungi should be plated onto Sabouraud dextrose agar without cycloheximide, which, if present, will inhibit growth of saprophytic fungi. Loeffler serum medium is used to speciate Moraxella based on growth characteristics. Löwenstein–Jensen medium is used for isolation of Mycobacterium tuberculosis, while atypical mycobacteria will grow on blood agar. Haemophilus requires hemin and nicotinamide adenine dinucleotide (NAD) for growth and will not grow unless they are present, as in chocolate agar.

6   B) Natamycin

     Natamycin is a polyene antifungal that is the drug of choice for filamentous fungi. Topical miconazole is the drug of choice for Paecilomyces lilacinus. Topical amphotericin is used to combat infections caused by Aspergillus and Candida spp. Flucytosine is used as an adjunctive agent for treatment of Candida spp.

7   B) Difluprednate 0.05%

     Options for managing primary HSV keratitis include trifluridine (Viroptic) nine times/day, vidarabine 3% ophthalmic ointment five times/day, or acyclovir 3% ophthalmic ointment five times/day. More recently, ganciclovir 0.15% gel (Zirgan) is available and is now the treatment of choice for topical treatment. Débridement of the corneal lesions in primary herpes may expedite recovery. Débridement may also be necessary for resistant virus strains. In severe or recalcitrant cases, oral acyclovir may be beneficial as adjunctive therapy. Famciclovir 500 mg twice daily or valacyclovir 500 to 1,000 mg twice daily for 5 days are the treatments of choice.

     Steroid drops are contraindicated in active herpetic epithelial disease. Steroids since can allow unchecked viral replication and are dangerous to use in such cases.

8   D) Associated with Down syndrome

     Megalocornea is usually an X-linked, isolated, nonprogressive congenital corneal enlargement with a horizontal corneal diameter of greater than 13 mm. It has been associated with systemic conditions such as Down, Marfan, and Alport syndromes, craniosynostosis, and facial hemiatrophy.

9   A) Limbal follicles

     Rheumatoid arthritis can manifest in the eyes in many ways, including dry eye, scleritis, stromal keratitis, peripheral ulcerative keratitis, and paracentral keratolysis. Both type III and IV hypersensitivity reactions have been implicated as well as vasculitis with inflammatory cell infiltration. The paracentral keratolysis (Fig. 10-66), also referred to as a sterile melt, can occur in relatively quiet eyes. This can progress rapidly to descemetocoele and perforation if not treated. Treatment includes protection of the surface from drying and exposure, adjuncts such as amniotic membrane grafts to promote healing, and in some situations, tectonic reinforcement.

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FIGURE 10-66

10  A) Peters anomaly

11  C) Both (Table 10-1)

TABLE 10-1

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12  D) Marfan syndrome

     Hurler syndrome, or mucopolysaccharidosis type 1, is associated with cloudy corneas, mental retardation, and skeletal defects. Turner syndrome has an XO chromosomal abnormality and is associated with ptosis, cataract, blue sclera, and nystagmus. Although Marfan disease is a disorder of collagen synthesis, blue sclera is not seen in this condition.

13  D) Superior limbic keratoconjunctivitis

     Stevens–Johnson syndrome, ocular cicatricial pemphigoid, and atopic keratoconjunctivitis are associated with conjunctival cicatrization. Other etiologies include, but are not limited to, chemical burns, trachoma, squamous cell carcinoma, infectious conjunctivitis, and scleroderma. Superior limbic keratoconjunctivitis does not cause conjunctival scarring, but it does cause a papillary reaction on the superior tarsus and keratinization and redundancy of the superior bulbar conjunctiva.

14  D) This process is nonprogressive.

     Sclerocornea is a nonprogressive, noninflammatory scleralization of the cornea. Ninety percent of cases are bilateral with no gender predilection. Half are sporadic. The remaining may be either dominant or recessive.

15  D) Posterior embryotoxon

     The ICE syndrome is a spectrum of diseases including progressive (essential) iris atrophy, Chandler syndrome, and Cogan–Reese syndrome (iris–nevus syndrome). All are characterized by a “hammered silver” appearance to the corneal endothelium and varying degrees of iris changes, such as corectopia, holes, and atrophy. Chandler syndrome typically has more severe corneal edema than the others. Essential iris atrophy is associated with polycoria and iris stretch holes. Cogan–Reese syndrome is characterized by numerous small pigmented nodules, iris atrophy, and pupillary distortion. Posterior polymorphous dystrophy of the cornea is considered by some to be related to the ICE syndrome. Posterior embryotoxon is anterior displacement of Schwalbe line and is not related to this syndrome.

16  A) Autosomal dominant inheritance

     The other findings are part of the Rieger syndrome, which includes Rieger anomaly (posterior embryotoxon, iris processes, iris atrophy) in addition to skeletal abnormalities.

17  D) ICE syndrome

     Each one of the conditions listed in this question is characterized by corneal clouding, noted pressures, normal stromal thickness, and normal corneal diameter. Peters anomaly is part of the spectrum of anterior segment dysgenesis and is associated with absence of corneal endothelium and Descemet membrane in the opacified area of the corneal leukoma. Congenital glaucoma is characterized by photophobia, tearing, enlarged corneal diameters, and increased eye pressures. ICE may have abnormalities of the endothelium; however, it does not usually have corneal edema or opacification as shown.

18  A) Dermolipoma

     Choristomas represent normal tissue in an abnormal location, whereas hamartomas represent abnormal growth of tissue in its normal location. Choristomas include dermolipomas and dermoids. Hemangiomas and lymphangiomas represent hamartomas.

19  C) Fluorescein

     Concentrated fluorescein, when applied to the corneal wound and viewed with a blue filter, appears dark black. If there is a corneal wound leak, the aqueous will dilute the fluorescein revealing a trail glowing yellow. This can be helpful even for pinpoint leaks. The rapidity of the dilution is representative of the size of the leak.

20  B) These are benign with no malignant potential.

     Limbal dermoids are well-circumscribed, white–pale yellow, round lesions that are choristomas (heterotopic congenital lesion that results from normal tissue residing in an abnormal location). The flattest meridian of the cornea is adjacent to the dermoid. They have no malignant potential. They tend to grow as the child grows, but usually very slowly. They can be associated with Goldenhar syndrome, a triad of epibulbar dermoids, facial anomalies, and skeletal anomalies.

21  B) Muscle

     Dermoids are choristomas containing ectodermal elements (skin, hair, fat, and sebaceous glands). Muscle tissue is not expected to be found in such a lesion.

22  A) Iris colobomas may be present.

     Goldenhar syndrome is a sporadic or autosomal dominant inherited syndrome of the first branchial arch. It consists of a triad: epibulbar dermoids; facial anomalies, including upper eyelid colobomas, preauricular skin tags, and aural fistulas; and skeletal anomalies.

23  D) All of the above

     Numerous medications are associated with the Stevens–Johnson syndrome. Some of these include penicillin, barbiturates, and sulfonamides, as well as some topical medications (sulfonamides, cycloplegics). Many infectious etiologies have also been implicated in precipitating a Stevens–Johnson syndrome. These include mycoplasma pneumonia, coxsackievirus, echovirus, and influenza virus.

24  D) Multiple endocrine neoplasia (MEN), type I

     MEN, type IIb (Sipple–Gorlin syndrome), is associated with enlarged corneal nerves, medullary carcinoma of the thyroid gland, pheochromocytoma, and mucosal neuromas. Enlarged nerves may be found in Refsum disease, ichthyosis, congenital glaucoma, and other diseases.

25  C) Figure 10-5C

26  C) Incision

27  A) Rheumatoid arthritis

     Figure 10-5A is a patient with atopy. Atopic patients have hyperactive immune systems that react to many environmental allergens. They can also have other allergic conditions including asthma, eczema, or seasonal allergies.

     Figure 10-5B is a chalazion. This is due to blockage of a meibomian gland orifice. The gland secretions collect, causing the nodular swelling of the lid. Incision and drainage is the definitive treatment.

     Figure 10-5C is due to HSV. The vesicular lesions on the upper lid can ulcerate and crust. Superinfection with bacteria is possible. Patients should be monitored for development of corneal dendrites.

     Figure 10-5D is a molluscum contagiosum lid lesion. The patients may have an associated follicular conjunctivitis. Treatment options include observation, chemical or thermal cautery, and excision. Incision of these lesions has also resulted in spontaneous involution of these lesions.

28  B) Haemophilus influenzae

     A number of bacteria are found commonly in the environment. These can be recovered from the eyelashes, and most of the time, they do not cause ocular disease. Corynebacterium spp., S. epidermidisMoraxella catarrhalis, and Streptococcus viridans are frequently found. Gram-negative organisms are not usually found on the ocular surface. Pathogenic bacteria include Haemophilus influenzaePseudomonas aeruginosaStreptococcus pneumoniaeS. aureusBacillus subtilis, and Neisseria gonorrhoeae.

29  C) Physostigmine acts as a respiratory poison to Phthirus pubis.

     Phthirus pubis (crab louse) infests pubic hair and eyelashes (Fig. 10-6) and is transmitted by sexual contact. Treatment is by mechanical removal or with bland ointments applied to the lids to suffocate adult lice. Physostigmine is effective as a respiratory poison against the lice but has many ocular side effects, limiting its effectiveness. Demodex is a normal commensal in adults living in meibomian glands. Classically, “sleeves” are found at the base of lashes, indicating Demodex infestation. Treatment is through lid scrubs. Collarettes are found more commonly with staphylococcal blepharitis.

30  C) Ketorolac

     Figure 10-7 shows a case of contact dermatitis associated with allergy to a topical medication. Patients often have an accompanying follicular conjunctivitis. Allergies occur with topical ophthalmic medications, including atropine, neomycin, apraclonidine (Iopidine), and dipivefrin (Propine).

31  C) Nocardia

     Figure 10-8 shows dacryocystitis. Swelling and tenderness in the area of the lacrimal sac is evident. Streptococci and staphylococci are known etiologies. Haemophilus is a common cause of dacryocystitis in children. Nocardia, a filamentous bacterium, is not a common cause of dacryocystitis but rather causes canaliculitis (less so than Actinomyces) and, rarely, keratitis or scleritis after trauma.

32  B) Topical prednisolone drops

33  D) Can produce keratin

     Squamous cell carcinoma of the limbus is rare. These lesions tend to be gelatinous, leukoplakic, or, occasionally, papilliform in appearance. Histologically, epidermoid and spindle-shaped cells replace the normal conjunctival epithelium. They can produce a whitish keratin plaque as they grow. Squamous cell carcinoma can primarily invade the cornea without conjunctival involvement. It can also invade intraocular structures. Most lesions may be treated with local excision with wide margins followed by cryotherapy. During larger resections, Mohs technique is valuable. Local radiotherapy with a ruthenium-106 plaque after excision may also be employed. Adjunctive therapy with mitomycin C has been used in several case reports. Topical steroids would not be expected to affect this lesion.

34  C) This lesion is confined to the conjunctiva and does not affect the underlying sclera.

     The differential diagnosis of a salmon-colored conjunctival lesion includes lymphoma, collection reactive lymphoid cells, and potentially amelanotic nevi. Conjunctival lymphoma usually presents as a painless, salmon-colored lesion on the bulbar conjunctiva. It may be an isolated finding or may be associated with systemic disease. Histopathologic finding of monoclonal B lymphocytes is associated with malignancy, so the finding of cellular atypia is not a criterion for malignant potential. Treatment may consist of surgery, local chemotherapy, or radiation. The proliferation of benign lymphoid cells (lymphoid follicle) may be a reaction to an allergic stimulus and typically responds well to steroid drops. An amelanotic nevus does not usually have a pinkish hue, but rather has a yellowish-tan coloration. Nevi can grow and increase in pigment during puberty.

35  A) Phlectenulosis

     Both phlectenulosis and staph marginal keratitis are thought to be due to hypersensitivity and the body’s immune reaction toxins produced by Staphylococcus bacteria that colonize the eyelid and lashes. Treatment with steroids (often in conjunction with antibiotics) is needed for fastest resolution of these conditions.

     A pseudogerontoxon occurs with peripheral corneal deposits associated with allergic conjunctivitis, limbal–vernal conjunctivitis, and atopy. It is similar in appearance to an arcus senilis, but is only two or three clock hours in length.

     Pterygia are more frequently associated with environmental irritants such as dryness, ultraviolet exposure, and dust/chemicals.

36  A) Have immunoglobulins bound to the conjunctival basement membrane

     Cicatricial pemphigoid is a chronic disease that affects mucosal surfaces typically in the elderly population. Immunoglobulins at the level of the basement membrane can be seen with immunofluorescent stains. Ocular cicatricial pemphigoid is usually bilateral (but may be very asymmetric) and associated with a chronic conjunctivitis. This leads to subconjunctival fibrosis and a drop in the number of goblet cells. The subconjunctival fibrosis also may lead to obstruction of the ducts of the lacrimal and accessory lacrimal glands. Progression usually results in symblepharon, foreshortening of the fornices, and ankyloblepharon. Keratinization of the conjunctival epithelium as well as corneal neovascularization and scarring are characteristic of end-stage ocular cicatricial pemphigoid.

37  B) Acanthotic epithelium over fibrovascular cores

     Figure 10-11 shows a conjunctival papilloma. In children and young adults, lesions may be multiple and are usually found on the palpebral conjunctiva. They are of viral origin, and spontaneous resolution is common. These lesions contrast with noninfectious papillomas, which occur in older adults and are almost always single in occurrence, often at the limbus. Atypical cells with dark nuclei may be found histopathologically. Small caliber vascular channels in a collagenase stroma are found in pyogenic granuloma, and lined nonkeratinizing stratified squamous epithelia are found in epithelial inclusion cysts.

38  A) Observation

     Past episodes with spontaneous resolution suggests viral origin. Incomplete excision or bleeding during excision may lead to seeding of other sites and multiple papillomas. Cryotherapy alone or in conjunction with excision with 2- to 3-mm margins is the preferred surgical treatment. Photocoagulation is not indicated.

39  B) Human papillomavirus

     Human papillomavirus DNA has been found in papillomatous lesions of the conjunctiva. This virus has also been implicated in cases of squamous cell carcinoma of the conjunctiva.

40  B) Squamous cell carcinoma

     Basal cell carcinoma is the most common malignant tumor of the eyelid skin, but squamous cell carcinoma is the most frequently occurring malignancy of the conjunctiva. Squamous papillomas are benign lesions that can, on rare occasions, undergo malignant transformation.

41  D) The entire thickness of the epithelium may be involved.

     Conjunctival intraepithelial neoplasia is the preinvasive stage of squamous cell carcinoma. By definition, there is no invasion of the basement membrane, but the entire thickness of the epithelium may be involved in conjunctival intraepithelial neoplasia (at which point it is called carcinoma in situ). It invariably occurs in the interpalpebral area and is characterized by leukoplakia, thickening of the epithelium, and abnormal vascularization. Treatment is by excisional biopsy with or without supplemental cryotherapy to the base.

42  D) Scleritis

     Causes of secondary-acquired conjunctival melanosis include Addison disease, radiation, and pregnancy. Black conjunctival adrenochrome deposits result from the oxidative by-products of epinephrine compounds.

43  C) Figure 10-14

44  C) Figure 10-14

45  B) Figure 10-13

46  A) Figure 10-12

     Conjunctival malignant melanoma (Fig. 10-12) is a pigmented elevated lesion that enlarges progressively with time. It occurs most commonly on the bulbar conjunctiva. These tumors are very vascular, and dilated vessels may be seen feeding the tumor. The prognosis is generally better than cutaneous melanomas. A systemic metastatic workup is necessary to direct treatment. Conjunctival melanomas can arise de novo (30%), from nevi (40%), or from primary acquired melanosis (30%).

     A conjunctival nevus (Fig. 10-13) is a flat or slightly elevated pigmented lesion of the bulbar conjunctiva. It may have epithelial inclusion cysts within its substance. These lesions can grow or enlarge during adolescence or with pregnancy. Suspicious lesions should be biopsied to rule out melanoma.

     Primary-acquired melanosis (Fig. 10-15) is a unilateral condition found in middle-aged white people. These multiple, superficial, flat patches of pigmentation develop into malignant melanoma in 20% to 30% of these patients. Excisional ­biopsy should be performed on any suspicious nodular lesions.

     Racial or ocular melanosis (Fig. 10-14) is found most commonly in pigmented individuals and represents benign collections of melanin in the conjunctiva. It appears as a perilimbal dusting of light brown pigment. No malignant potential exists.

47  D) Distant metastasis

48  A) Simple excision, leaving bare sclera

49  C) Prolonged actinic exposure is a risk factor.

     Figure 10-16 shows a pterygium of the right eye. Pterygia are wing-shaped folds of conjunctiva and fibrovascular tissue that invade the superficial cornea. The exact etiology is not known, but a strong causal relationship has been documented with ultraviolet light exposure. Destruction of Bowman layer and changes in corneal astigmatism often occur. If inflamed, they may become hypertrophic with localized changes of the adjacent cornea, which may include punctate keratopathy and even dellen formation. Iron deposition at the leading edge of the pterygium is known as a Stocker line. They may be observed, but excision is often indicated if the visual axis is threatened or if extreme irritation exists. The recurrence rate is significant, with approximately 40% recurring by simple excision. Conjunctival autograft and amniotic membrane graft may lower recurrence rate according to some studies. Application of mitomycin C may also prevent recurrence. These lesions are rarely malignant, and metastasis would be extremely uncommon.

50  B) Resection of the adjacent conjunctiva may be indicated.

     Figure 10-17 shows superior limbal hyperemia and mild keratitis consistent with superior limbal keratoconjunctivitis. Superior palpebral conjunctival papillary reaction, micropannus, and filaments may also be present. Rose bengal or lissamine green (Fig. 10-67) are vital dyes that highlight the affected conjunctiva. Treatment may include 0.5% to 1.0% silver nitrate solution (not a silver nitrate stick), pressure patching, mechanical scraping, conjunctival resection, or bandage contact lens. Thyroid dysfunction must be considered and thyroid function tests performed.

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FIGURE 10-67

     Reduced corneal sensation is a common finding in herpetic disease and is not associated with superior limbic keratoconjunctivitis. Floppy eyelid syndrome, which is most common in obese individuals and is characterized by easy eversion of superior tarsus and papillary response, responds well to sleeping with a protective eye shield.

51  D) Decreased thyroid-stimulating hormone levels

     Thyroid abnormalities have been associated with superior limbic keratoconjunctivitis. A skin rash may be found in herpes simplex or zoster infections.

52  D) Topical mast cell stabilizers or corticosteroid drops

     Although giant papillary conjunctivitis (GPC) is historically classified as an ocular allergy, it is likely secondary to mechanical irritation. GPC does not signify a systemic allergic predisposition. It is usually associated with soft contact lenses (rarely caused by rigid gas permeable lenses), ocular prostheses, or exposed sutures. Large follicles (>1.0 mm in diameter, typically confined to the upper palpebral conjunctiva), conjunctival hyperemia, and a mucus discharge are signs associated with GPC. Limbal follicles (typically associated with vernal conjunctivitis) have also been reported. Treatment includes mast cell stabilizers, corticosteroids, improving lens hygiene, or changing contact lenses to a better-tolerated lens. If contact lens wear is discontinued, GPC generally resolves. Moxifloxacin is a fourth-generation fluoroquinolone. Doxycycline is useful in treating Chlamydia trachomatis and adult inclusion conjunctivitis. These are not necessary because this is not an infectious condition.

53  A) Figure 10-19M

54  C) Figure 10-19N

55  A) Superior limbic keratitis

     The staining patterns correspond to the conditions listed:

     B = keratoconjunctivitis sicca

     D = contact lens–induced keratoconjunctivitis

     E = soft contact lens wearer

     J = superior limbic keratoconjunctivitis

     K = vernal catarrh, “floppy eyelid” syndrome

     M = lagophthalmos

     N = focal epithelial keratitis (Thygeson’s, EKC, molluscum)

56  B) Lithium

     Cornea verticillata is a whorl-like deposition of material in the corneal epithelium. Drugs that may cause this include amiodarone, chlorpromazine, chloroquine, indomethacin, meperidine, and tamoxifen.

57  A) Fabry disease

     Fabry disease is a glycolipidosis. Findings include cornea verticillata; cataracts; angiokeratomas; vascular anomalies of the heart, kidney, and brain; and burning pain in the hands and feet.

58  D) The cystine deposits begin centrally within the anterior stroma and progress to involve the entire cornea.

     In cystinosis, corneal crystals are evident in the anterior stroma and are often found on routine examination. Three forms of cystinosis are known, the infantile form being most severe with dwarfism, rickets, and renal failure. Most die before puberty, but some reach adulthood through dialysis or renal transplantation. The adolescent form is similar to, but less severe than, the infantile form, and both are autosomal recessive. Those with the adult form are usually asymptomatic and do not have the systemic findings indicated earlier. Mode of inheritance is uncertain and life expectancy is normal. All forms have in common the deposition of cystine crystals in the cornea and conjunctiva (as well as in the uveal tract).

59  D) Descemet membrane

60  B) The corneal findings can be used to monitor therapy.

     Figure 10-21 shows a Kayser–Fleischer ring in the cornea, which represents deposition of copper in the posterior lamella of Descemet membrane. Such a ring may be seen in Wilson disease, primary biliary cirrhosis, chronic hepatitis, or progressive intrahepatic cholestasis of childhood, but only patients with Wilson disease will show neurologic findings. Treatment of Wilson disease is with penicillamine, and the Kayser–Fleischer ring will disappear with appropriate treatment, thereby providing a means to monitor therapy. The defect in Wilson disease is a decreased production of ceruloplasmin by the liver.

61  C) Trachoma

     Figure 10-22 shows Herbert pits found in trachoma. They are the scarred remnants of inflammatory nodules on the limbus. Horner–Trantas dots, seen in vernal keratoconjunctivitis, are focal limbal infiltrates of eosinophils. Staphylococcal marginal keratitis has corneal infiltrates characteristically with clear cornea between it and the limbus.

62  D) Leukoplakia

     Manifestations of trachoma include superior corneal pannus, conjunctival scarring, and superior conjunctival follicles. Leukoplakia is suspicious for squamous cell carcinoma of the conjunctiva.

63  B) This patient may have deposition of copper in the liver, kidneys, and brain.

     Figure 10-23 shows calcific band keratopathy with a degeneration of the superficial cornea involving deposition of calcium hydroxyapatite, mainly in Bowman layer. Hepatolenticular degeneration, or Wilson disease, is associated with a Kayser–Fleischer ring in the peripheral cornea. Band keratopathy may be a hereditary condition or may be associated with chronic mercurial exposure. Other causes include chronic ocular disease, inflammation, hypercalcemia, or hyperphosphatemia.

64  A) Ethylenediaminetetraacetic acid (EDTA)

     EDTA is able to chelate the calcium found in band keratopathy. It is necessary to scrape to epithelium to expose the calcium to the EDTA. Penicillamine binds heavy metal ions, such as iron, copper, and lead and may be helpful in Wilson disease and hemochromatosis. Acetylcysteine is an anticollagenolytic agent.

65  B) Pathologically, it appears as lipid deposition in the cornea.

     Spheroidal degeneration involves proteinaceous deposits in the superficial stroma that are thought to be caused, in part, by sunlight exposure. It is usually bilateral and is more common in men.

66  D) Epithelium remains intact.

     Figure 10-24 shows a case of Terrien marginal degeneration. Peripheral thinning occurs superiorly first, then circumferentially. Unlike Mooren ulcer or peripheral ulcerative keratitis of autoimmune disease, thinning occurs with an intact epithelium in an essentially quiet eye. Thinning to perforation is rare. Against-the-rule astigmatism is often induced. Thinning that is more apparent than real is a characteristic of furrow degeneration, a benign condition that does not affect vision.

67  A) Biopsy of the adjacent conjunctiva may show increased plasma cells.

     Figure 10-25 shows a case of Mooren ulcer. Note the conjunctival injection, ulceration of the peripheral cornea, and undermined leading edge. Pain may be severe and accompanied by photophobia. An autoimmune process likely plays a role as immunoglobulin, complement, and plasma cells are found in the adjacent conjunctiva. Two clinical types have been described. The type found in older adults is usually unilateral accompanied by mild pain, and it is more responsive to therapy such as topical steroids. Corneal perforation is rare. The other type is bilateral, often found in younger black males, and rapidly progressive. These lesions respond poorly to therapy, and systemic immunosuppressives are often necessary.

68  C) This is a bilateral condition.

     Pellucid marginal degeneration is a bilateral, nonhereditary condition. There is protrusion of the cornea above the area of maximal thinning inferiorly in the cornea, whereas in keratoconus, corneal protrusion is at the point of maximal thinning. It affects both men and women equally, and is frequently diagnosed between 20 and 40 years of age. No vascularization or lipid occurs, and vision is decreased secondary to high irregular astigmatism. Surgical treatment, if needed, includes peripheral tectonic grafts, but refractive treatments such as PRK and LASIK would not be appropriate for this condition.

69  C) Spontaneous perforation

     The corneal topography shown is characteristic of keratoconus. Steepening inferotemporally is evident in this particular case (Fig. 10-68), but it may be inferior, inferonasal, or even central on corneal topography depending on the site of thinning and cone formation. Almost all cases are bilateral, but they may be very asymmetric with perhaps only mild astigmatism in one eye. Scissoring of the red reflex on retinoscopy is often an early sign. Deposits of iron around the base of the cone (Fleischer ring) and deep vertical stromal lines (Vogt striae) (Fig. 10-69) are also characteristic of keratoconus. Acute ruptures of Descemet membrane or acute hydrops may occur, leading to corneal edema that often resolves spontaneously, leaving stromal scarring. Corneal perforation is rare unless associated with trauma.

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FIGURE 10-68

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FIGURE 10-69

70  D) Photorefractive keratectomy (PRK)

     Spectacle correction may be adequate in early or mild cases of keratoconus if acceptable visual acuity can be achieved. A hard contact lens will neutralize irregular astigmatism, although fitting may be difficult, especially in advanced cases with pronounced cones. If vision is unacceptable with hard contact lenses, proper fitting cannot be performed, or, if contact lens intolerance arises, penetrating keratoplasty should be considered. Prognosis for corneal transplant in these patients is excellent. Corneal cross-linking with riboflavin is being studied as a way to strengthen the cornea and reduce the progression of keratoconus. PRK using the excimer laser is contraindicated in keratoconus as a result of corneal thinning and potential progression of the disease.

71  A) Hypertonic saline

     This keratoconus patient has developed hydrops from a rupture of Descemet membrane. Fluid from the anterior chamber can flow into the corneal stroma, causing edema and opacification. The initial therapy includes topical steroids, cycloplegics, and hypertonic saline drops. PKP or DSEK are both potential surgical treatments, but the hydrops may resolve enough that no surgery is needed.

72  D) No tests needed, diagnosis based on clinical appearance

73  B) Epithelial dendrites

     This picture show the classic rash associated with herpes simplex. In this condition, involvement of the eyelid margin with blisters is frequently associated with ocular surface infection, so the cornea and conjunctiva should be carefully examined for epithelial dendrites. The appearance of the classic branching, ulcerated dendrites on the ocular surface is diagnostic for this condition and no additional tests are needed.

     Herpes zoster can present in a similar fashion, but usually in an older age group. There can also be epithelial dendrites, but these have a different configuration than the ones with HSV.

     Mucopurulent conjunctivitis due to viruses such as adenovirus can cause eyelid swelling, but not the dermatitis as shown here. Gonococcal hyperpurulent conjunctivitis is very distinctive in the copious quantity of discharge as well as its rapid progression to corneal perforation.

     Allergic eye disease (limbal–vernal, atopic) can be found with an allergic dermatitis. The history of itching and findings of limbal or palpebral follicles are characteristic of these conditions. These patients may be more prone to herpetic infections as well due to abnormalities of their immune system.

74  C) The recessive form is nonprogressive, whereas the dominantly inherited form is slowly progressive.

     Nystagmus is associated with the recessive, but not the dominant, form of the disease. There are no known associated ocular or systemic diseases. Corneal edema is present at birth in the recessive form, whereas corneal decompensation usually does not occur until the first or second year of life in the dominant form of the disease.

75  B) Symptoms of pain, tearing and photophobia

     Congenital hereditary stromal dystrophy is a rare, autosomal dominant condition presenting at birth as a central, anterior stromal feathery opacity that may cause reduced visual acuity. The corneal periphery is clear. There is no pain, photophobia, or tearing because IOP is normal.

76  A) Lattice stromal dystrophy

     The most common stromal dystrophy is lattice, followed by granular. Meesmann dystrophy is a very rare epithelial dystrophy.

77  C) Acid mucopolysaccharides

78  B) The disease is caused by a defect in the synthesis of keratan sulfate.

     Figure 10-29 shows macular corneal dystrophy, the least common of the classic stromal dystrophies. It usually leads to symptoms at an earlier age than either lattice or granular dystrophy and is caused by an error in the synthesis of keratan sulfate, leading to unsulfated keratan that is not degraded effectively. These mucopolysaccharide deposits accumulate throughout the cornea (including the periphery) and stain with colloidal iron and alcian blue.

79  D) Skin findings and nerve palsies are manifestations of systemic involvement.

80  C) Alcian blue

     Lattice corneal dystrophy, shown in Figure 10-30, is an autosomal dominantly inherited corneal dystrophy that consists of amyloid deposition into the anterior corneal stroma, which is best seen by retroillumination. There are two recognized forms of the disease: type I is localized to the cornea, and type II (Meretoja syndrome) involves widespread deposition of amyloid and results in systemic findings such as dry, lax skin; cranial nerve palsies; abnormal ears; and a mask facies. Lattice dystrophy is a cause of recurrent erosion because the amyloid deposition in the anterior stroma leads to weak adherence of the epithelium to Bowman layer. Amyloid stains with Congo red, metachromatically with crystal violet, and also with thioflavin T. It also exhibits birefringence and dichroism under the polarized microscope.

81  C) Recurrent erosions are common.

     Recurrent erosions are uncommon in granular dystrophy as opposed to lattice dystrophy, in which they occur much more frequently. Granular dystrophy is an autosomal dominant inherited disease that occurs early in life, although symptoms do not usually occur until years later. In macular corneal dystrophy, the intervening cornea is cloudy, whereas in granular dystrophy, it remains clear. Masson trichrome stains the hyaline deposits vividly.

82  C) Both

83  C) Both

84  D) Neither

85  A) Figure 10-31

86  D) Neither (Table 10-2)

TABLE 10-2 Classic Stromal Corneal Dystrophies

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87  B) The lesions are among the most common to recur after penetrating keratoplasty.

     This is a case of Reis–Bucklers dystrophy, an autosomal dominant, progressive dystrophy. Symptoms often develop in adulthood and include painful recurrent erosions and decreased visual acuity. Lesions occur at the level of Bowman layer. Treatment may include superficial keratectomy, excimer laser phototherapeutic keratectomy, or penetrating keratoplasty. Recurrence in the graft is common in both Reis–­Bucklers dystrophy and lattice dystrophy.

88  A) Disruption and absence of Bowman layer

     Histopathology shows replacement of Bowman layer by a fibrocellular tissue. “Peculiar substance” is found in epithelial cells in Meesmann dystrophy. Amyloid exhibits birefringence and dichroism when viewed under a polarizing microscope. Oil Red O stain is used to stain the stromal opacities made of cholesterol in ­Schnyder crystalline dystrophy.

89  C) It occurs as a unilateral disease.

     Anterior membrane (map-dot-fingerprint) dystrophy of the cornea occurs bilaterally but may be asymmetric. It may be dominantly inherited. Characteristic clinical findings consist of cystic, geographic, or fingerprint formations that may be seen with sclerotic scatter or retroillumination. Pathologic findings consist of thickened basement membrane, abnormal epithelial cells with microcysts, and fibrillar material between the basement membrane and Bowman layer. Symptoms typically occur between the fourth and sixth decades of life. Treatment options include topical lubricants, 5% sodium chloride, scraping, patching, anterior stromal puncture, or possibly phototherapeutic keratectomy.

90  A) Multilaminar Descemet membrane studded with excrescences

     Patients with Fuchs endothelial dystrophy have malfunctioning Na–K ATPase pumps in the cell wall of the endothelial cells. This diminished pump function results in swelling of the corneal stroma. Cytochrome oxidase is also reduced, which may indicate a decrease in the metabolic activity of the endothelial mitochondria. Histologic examination would reveal a multilaminar Descemet membrane studded with excrescences (Fig. 10-70). This abnormal tissue is a nonspecific response. As the disease progresses, specular microscopy may demonstrate a more pleomorphic endothelium with a reduction of endothelial cell density.

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FIGURE 10-70

     Pigment deposition in the trabecular meshwork could result in elevated IOP and corneal edema. Descemet breaks with keratoconus or birth trauma would be apparent as discrete lines visible on retroillumination.

91  C) Specular microscopy

     Fuchs endothelial dystrophy is an autosomal dominant (variable) corneal dystrophy that usually affects postmenopausal women. Clinical findings may include corneal guttae and Descemet folds. In more advanced disease with endothelial decompensation, stromal, epithelial edema, and epithelial bullae may be present. There is polymegathism and pleomorphism of the corneal endothelial cells with excrescences and thickening of Descemet membrane best evaluated using specular microscopy. Symptoms are usually worse in the morning as a result of decreased surface evaporation during sleep. Similar findings can be duplicated by having the patient patch his or her affected eye for several hours. Pachymetry demonstrates thickening of the central cornea but does not indicate the etiology.

92  A) Bandage contact lens may be used to treat ruptured bullae.

     Treatment measures are aimed at limiting visual dysfunction and discomfort due to epithelial breakdown and ruptured bullae. Hypertonic solutions and ointments may provide some relief, but they do little when the edema is advanced. Some feel that lowering IOP may help control edema. Both hypertonic solutions and IOP–lowering agents, however, are only temporizing measures and are not long-term solutions. Ruptured bullae may be treated with patching or bandage contact lens. Penetrating keratoplasty carries a good prognosis in these patients. Anterior stromal puncture is not indicated in Fuchs dystrophy, but it may be helpful in treating cases of recurrent erosion.

93  A) Retained viscoelastic material within the anterior chamber

     Corneal edema following cataract surgery can be due to a number of factors. In Figure 10-36, there are prominent Descemet and deep stromal folds rather than microcystic corneal edema. Injury to the endothelial cells or to Descemet membrane is to be implicated. Retained viscoelastic would cause an elevation in IOP and the development of corneal bullae and microcystic edema on the epithelial surface.

94  A) Meesmann dystrophy

     All of these autosomal dominant dystrophies, except Meesmann dystrophy, have been linked to chromosome 5q31. Meesmann dystrophy involves thickened epithelium and basement membrane, with epithelial cells containing an electron-dense accumulation of “peculiar substance.” Reis–Buckler dystrophy is a progressive dystrophy that affects Bowman layer. Avellino (granular–lattice) dystrophy has hyaline deposits typical of granular dystrophy and amyloid deposits typical of lattice dystrophy seen.

95  D) Best treated by excimer laser phototherapeutic keratectomy

     Salzmann nodular degeneration is associated with many conditions, including trachoma, keratitis associated with rosacea, map-dot-fingerprint dystrophy, and vernal keratoconjunctivitis. These midperipheral, gray–blue subepithelial nodules gradually appear with chronic inflammation. After the inflammation subsides, these nodules persist. Histologically, there may be a nodular collagenous material between the epithelium and the intact Bowman layer. This may allow for a cleavage plane during removal. Treatments include superficial keratectomy and lamellar keratoplasty. Excimer laser phototherapeutic keratectomy can be performed, but it is not first-line treatment.

96  C) Discontinue her fluoroquinolone drop.

     Figure 10-38 shows the precipitation of ciprofloxacin onto the corneal surface after cataract surgery. Corneal deposits do not result from the use of other fluoroquinolones. Disruption of the epithelial surface may permit the deposits to accumulate more easily. Discontinuation of the ciprofloxacin drops will allow the deposits to slowly resolve.

     A bacterial or fungal infection would be very unusual in such a quiet eye. This may be confused with a shield ulcer from limbal–vernal keratoconjunctivitis, but the shield ulcer has a grayish stromal base with an overlying epithelial defect.

97  A) Corneal sensation is reduced.

     Thygeson superficial punctate keratitis is a bilateral (although it may be asymmetrical) disease consisting of a course punctate keratitis without an accompanying conjunctivitis. These lesions may or may not stain with fluorescein. Corneal sensation is normal. It is very responsive to topical corticosteroids, but this may increase the rate of recurrence. Topical cyclosporine may be beneficial. No clear etiology has been established, but a viral etiology has been postulated (although antiviral medications have not proven beneficial). People possessing the histocompatibility antigen HLA-DR3 have a 5.65 greater relative risk of having Thygeson superficial punctate keratitis.

98  C) Débridement

     This is a typical photograph of adenovirus keratoconjunctivitis; serotypes 8, 11, and 19 are the most common causative agents. Therapy is mainly supportive. Cool compresses and lubrication can be recommended as can topical vasoconstrictors. There is little evidence to support the use of topical antibiotics. The use of topical steroids is controversial and is only indicated for the presence of a conjunctival membrane or pseudomembrane, marked foreign body sensation and chemosis, and reduced vision due to the epithelial and subepithelial keratitis. Débridement is not necessary for this condition.

99  D) Do not share towels or pillows.

     Because adenovirus does not have a lipid coat, alcohol based sanitizers are ineffective. Adenovirus is contagious for approximately 2 weeks. Patients should be told to wash all fomites like towels and pillows.

100 C) Staphylococcus aureus

101 A) Blepharitis

102 A) Prednisolone acetate

     Figure 10-41 shows a staphylococcal marginal infiltrate, which is thought to be caused by a hypersensitivity to staphylococcal exotoxins. The subepithelial infiltrate typically has a lucent area separating it from the limbus. The epithelium overlying the infiltrate may break down, causing many of the patient’s symptoms. Patients commonly have blepharitis and meibomitis, although blepharitis can be noticeably absent. Mild steroid drops (prednisolone 0.125%) effect quick resolution. A combination antibiotic and steroid drop is often an excellent choice. Slight corneal thinning and vascularization may be the only remnants of a previous episode.

103 D) Haemophilus influenzae

     Figure 10-71 shows severe infectious keratitis; this clinical picture may be caused by many bacteria, such as S. aureus, S. epidermidis, and P. aeruginosa. Most bacteria require a break or disruption of the corneal epithelium to gain access and subsequent adherence to the underlying cornea. Hemophilus is one organism that can invade intact epithelium and establish infection. Other bacteria that do not require epithelial disruption include Neisseria spp., Corynebacterium spp., and Listeria spp.

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FIGURE 10-71

104 D) Disciform keratitis

     Conjunctival injection, a large epithelial defect, and corneal infiltrate are present in Figure 10-44. Infectious keratitis, bacterial infection, and fungal infection should be considered. A noninfectious or sterile keratitis, such as that from topical anesthetic abuse, should also be considered. Disciform keratitis clinically shows corneal stromal edema, underlying keratic precipitates, and mild to moderate iridocyclitis. It is classically described in cases of herpes simplex, but it may also be seen in herpes zoster, mumps, varicella, and possibly chemical injury.

105 C) Corneal biopsy

     Corneal smears and cultures would help identify an infectious etiology. However, a negative culture would not rule out an infectious cause. The patient should be questioned about the use of any topical medication other than those prescribed. In this case, the patient admitted to the use of topical proparacaine every 30 minutes. Topical anesthetics are known to be toxic to the corneal epithelium and can cause a nonhealing epithelial defect, stromal infiltrate, hypopyon, and corneal perforation with loss of the eye. Clinical suspicion is critical in making this diagnosis. Testing corneal sensation may be helpful in a significantly abnormal case. Corneal biopsy is not indicated at this time, but it may be needed if the other diagnostic tests are unrevealing.

106 B) The grayish areas are epithelial cells and basement membrane in the stroma.

     The picture shows epithelial ingrowth after LASIK surgery. Mild, non–visually significant epithelial ingrowth that extends 2 mm or less from the flap edge can be watched. The rests of cells are not infectious and will not respond to antibiotics or steroids. Treatment options for thick, pronounced ingrowth include lifting the flap and scraping epithelial cells away. Typically, antibiotic and steroid drops are used after LASIK and after lifting a LASIK flap. Adjunctive measures such as the Nd:YAG laser can be used for epithelial ingrowth.

107 D) Lifting the flap and scraping

108 C) Both

109 C) Both

110 B) Herpes zoster keratitis

111 A) Herpes simplex keratitis

112 C) Both

     A number of features are shared between dendritic infection from HSV and herpes zoster virus (HZV). Both may have an accompanying skin rash (along a dermatome in HZV) and corneal anesthesia. The active viral replication causes sloughing of epithelial cells in HSV, whereas in HZV, the epithelial cells are swollen and heaped up. Both conditions may recur. Iritis and elevation in IOP can be found with both viral infections; however, iris atrophy is more common with HZV.

113 D) It is an indicator of elevation of systemic lipid levels.

     Cholesterol and neutral fats accumulate in crystalline flecks in the corneal stroma in Schnyder crystalline corneal dystrophy. The patients have excellent acuity despite a dense collection crystals in the visual axis. Recurrence in penetrating keratoplasties is possible. Although some patients have elevated lipid levels in association with this condition, the crystals are not indicative of a particular lipid level. Schnyder’s can be found in patients with normal lipid profiles as well.

114 B) Edges of these lesions stain with rose bengal.

     Pictured is dendritic keratitis caused by HSV. The previous episode of redness may have represented primary ocular herpes, which usually lasts only a few days. The duration of dendritic keratitis is approximately 3 weeks, followed by resolution. Topical antiviral therapy is most commonly used for treatment to speed recovery, but simple débridement may be effective. Histopathology shows intranuclear inclusion bodies (Lipschütz bodies or Cowdry type A inclusions). Intracytoplasmic inclusions are present in chlamydia.

     Epithelial cells bordering dendritic lesions are devitalized and laden with virus, staining well with rose bengal; this is in contrast to pseudodendritic lesions of herpes zoster, which stain poorly.

115 D) The corneal opacity is beneath the epithelium.

     Figure 10-47 shows a ghost dendrite. Ghost dendrites may occur after the resolution of primary HSV infection. If they are not visually significant, they do not require treatment. Because the excimer laser is known to activate inactive HSV infection, the patient is not an ideal candidate for PRK.

116 A) Oral acyclovir will expedite recovery.

     Figure 10-48 shows disciform keratitis, in this case, secondary to HSV infection. Topical steroid therapy decreases the inflammatory response but may prolong disease activity, and tapering off steroids may be difficult. For this reason, peripheral lesions without significant neovascularization and central lesions that allow good visual acuity may be best untreated. When treatment is necessary, the lowest effective topical steroid dose is used, and most agree that a dose of prednisolone acetate 1% used more than once a day should be accompanied by a topical antiviral agent drop for drop. The Herpetic Eye Disease Study showed that no statistical or clinically significant benefit resulted from systemic acyclovir in patients receiving concomitant topical corticosteroids and antivirals with regard to treatment failure, resolution of keratitis, time to resolution, or 6-month best-corrected visual acuity. However, more patients in the acyclovir group had improvement in visual acuity after 6 months.

117 D) Simple mechanical débridement may be curative when confined to the corneal epithelium.

     The history described is classic for acanthamoeba keratitis. Patients often are contact lens wearers who clean their lenses with homemade solutions or tap water. Other risk factors include corneal trauma, direct exposure to soil, and exposure to standing water (well water, ponds, lakes). Pain commonly accompanies acanthamoeba keratitis but is often out of proportion to the clinical examination. Figure 10-49 shows a ring infiltrate corneal ulcer, a characteristic but late finding. Early stages may show small epithelial cysts, whereas late stages may show suppurative ulceration with hypopyon. More prominent corneal nerves, because of perineural infiltration, are a feature of this infection but are not pathognomonic. These free-living protozoans may grow well on standard media (blood and chocolate agar); however, they grow best on nonnutrient agar overlaid with Escherichia coli or Enterococcus. Various stains may allow identification with light microscopy, and confocal microscopy can be used to visualize the organisms in vivo. ­Figure 10-72 shows a Geimsa stain and Figure 10-73 shows the appearance of cysts on a wet mount. Treatment includes simple débridement if infection is limited to the epithelium. Topical agents, including neomycin, propamidine, polyhexamethylene biguanide, chlorhexidine, and oral ketoconazole, may be of benefit. More severe infections may require corneal transplantation but may be complicated by recurrences in the graft.

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FIGURE 10-72

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FIGURE 10-73

118 B) Double-walled cysts

     Corneal ulceration in a contact lens wearer is most commonly caused by gram-negative rods, especially Pseudomonas spp. In this case, however, Acanthamoeba is the infectious agent, and the double-walled cyst form or the trophozoite is seen in corneal biopsy. Acid-fast pleomorphic rods may be Mycobacterium spp., which rarely cause keratitis. Branching hyphae are seen in fungal infections, and branching filaments may be found in infections caused by Nocardia spp. and Actinomyces spp.

119 B) Topical cefazolin

     Pictured is a Pseudomonas aeruginosa corneal ulcer in a contact lens wearer. Initial antimicrobial therapy should provide broad-spectrum coverage for both gram-positive and gram-negative microbes. Combination therapy with a cephalosporin or vancomycin for gram-positive coverage and an aminogylcoside (tobramycin or gentamicin) provides excellent coverage. Monotherapy with fourth-generation fluoroquinolones (moxifloxacin and gatifloxacin) is also used. They have shown to provide coverage against both gram-positive and gram-negative microbes. Monotherapy with a cephalosporin (cefazolin) does not provide adequate gram-negative coverage.

120 A) Congenital syphilis

     Tuberculosis, herpes simplex, and acquired syphilis would more likely cause a unilateral interstitial keratitis. Congenital syphilis causes a bilateral interstitial keratitis that may not become manifest until the patient is 10 to 20 years of age. Cogan syndrome affects middle-aged adults with hearing loss, vertigo, and interstitial keratitis.

121 D) Bell palsy

     Figure 10-51 shows a cornea with severe punctate epithelial erosions in the exposed interpalpebral area, such as that seen with exposure keratopathy. Causes for this include lagophthalmos, Bell palsy, proptosis with incomplete closure of the lids, ectropion. The incomplete blink leaves the inferior third of the cornea exposed and dry. Sjögren syndrome is a global dry eye state with decreased mucin production by the goblet cells and decreased tear production. It would appear as drying of the whole cornea. A chemical splash also would affect more of the cornea than is pictured here.

122 A) Tarsorrhaphy

     A tarsorrhaphy would be an excellent treatment to help close the lids and reduce the area that remains exposed. A rigid gas permeable contact lens would not be a good choice for this eye. Penetrating keratoplasties in dry eyes such as this have high rates of failure. Anterior stromal micropuncture may be useful for patients with recurrent erosions.

123 C) Corneal scarring and vascularization are successfully treated with penetrating keratoplasty.

124 A) Dapsone

     Pictured in Figure 10-52 are conjunctival scarring and symblepharon formation caused by ocular cicatricial pemphigoid. Patients often present with symptoms of dry eyes and nonspecific erythema. Extraocular mucosal and skin lesions are common. Subconjunctival fibrosis and symblepharon formation are important findings. Severe dry eyes, corneal scarring, and vascularization develop. Conjunctival scrapings show lymphocytes, plasma cells, and eosinophils. Immunopathology from conjunctival biopsy specimens show deposits of IgA along the basement membrane zone. It is imperative to question the use of topical ocular preparations when encountering this clinical picture. Other causes of cicatrizing conjunctivitis or pemphigoid-like presentation include the use of antivirals, miotics (both direct and indirect), epinephrine, and timolol. Differential diagnosis also includes chemical burns, radiation treatment, ocular rosacea, and the Stevens–Johnson syndrome. Strictly monocular findings may be postsurgical, but they should also raise suspicion of conjunctival carcinoma. Treatment for ocular cicatricial pemphigoid involves systemic immunosuppression. Treatment options include oral dapsone therapy with systemic prednisone for acute exacerbations. Cyclophosphamide or other immunomodulatory therapy may be beneficial. Because this is due to a systemic autoimmune disease, topical cyclosporine will be of limited benefit.

125 D) Staphylococcal hypersensitivity

     Staphylococcal hypersensitivity may cause irritation, corneal infiltrates, and a localized conjunctivitis. It does not result in conjunctival scarring.

126 D) Floppy eyelid syndrome

     Filaments are strands of mucus and epithelial cells that have not been sloughed by the blinking action of the lids. They can be found in many dry eye states, with pro- longed patching, and in conditions such as superior limbic keratoconjunctivitis. Floppy eyelid syndrome would have a papillary conjunctival reaction. When floppy eyelid syndrome is an isolated condition, filaments are not associated with it.

127 B) Long-term steroids are helpful.

     Figure 10-54 shows a corneal epithelial defect. In a cornea with markedly abnormal sensation without trauma, this defect most likely represents neurotrophic keratitis. This condition is caused by trigeminal nerve palsy or inflammation, especially the ophthalmic division. Causes include herpes simplex or zoster, surgery, strokes, and tumors. Evidence of herpetic etiology includes a previous history of a red eye with or without pain, shingles, lid and/or conjunctival scarring, corneal stromal haze or scarring, endothelial keratic precipitates, iritis, and sectoral iris atrophy.

     An oval epithelial defect is usually present in the inferior half of the cornea with rolled, thickened edges. Chronic defects may be accompanied by stromal loss. Treatment includes lubricants, antibiotic prophylaxis, patching, or lid taping. Bandage contact lenses may be considered but must be used with caution. Punctal occlusion may be beneficial. Chronic inflammation at the level of the epithelial basement membrane may inhibit complete healing of the epithelial defect; therefore, low-dose topical steroids may promote healing in some cases. However, steroids must be used with great caution as they may potentiate collagenase activity and corneal thinning. Therefore, they are generally not indicated. Tarsorrhaphy may be necessary in refractory cases, especially in those with markedly abnormal corneal sensation and lid disorders.

128 D) All of the above

     For a traumatic hyphema with normal IOP, observation is appropriate with the modalities to reduce the risk of a rebleed; this includes bed rest, elevation of the head, and patching of the eyes to reduce eye movement. Oral aminocaproic acid may also be helpful to prevent a rebleed. In African-American patients, a sickle cell prep is essential.

129 A) Anterior chamber washout

     If IOP is elevated in hyphema and there are no signs of corneal blood staining, medical management of the IOP is appropriate. A carbonic anhydrase inhibitor may not be the best agent to lower IOP with the possibility of sickle cell in a African-American patient. If the IOP still remains elevated and/or signs of corneal blood staining appear, then surgical intervention is necessary with an anterior chamber washout. Intracameral t-PA may be able to lyse the clot; however, the blood breakdown products will still remain in the anterior chamber, and the IOP will be unaffected.

130 D) Fleck dystrophy

     Superficial phototherapeutic keratectomy uses the excimer laser to ablate the superficial layers of the cornea (epithelium, Bowman layer, or superficial stroma) to remove dystrophic or scarred tissue. Granular and Reis–Buckler dystrophies are associated with recurrent erosions, which are treated by superficial keratectomy or phototherapeutic keratectomy. Epithelial basement membrane dystrophy (also called map-dot-fingerprint or Cogan microcystic dystrophy) is an abnormality in epithelial maturation, turnover, and production of basement membrane. Removal of damaged epithelium and anterior basement membrane is effective and can be done with phototherapeutic keratectomy. Fleck dystrophy is a nonprogressive, usually asymptomatic stromal dystrophy with gray–white opacities in the stroma. The epithelium, Bowman layer, Descemet membrane, and endothelium are not affected.

131 D) Severe uveitis and glaucoma may occur.

     Chemical injury with acid substances causes denaturation and precipitation of proteins, which limits ocular penetration. Alkali burns, in contrast, penetrate the globe rapidly with progressive damage. Symblepharon formation, severe uveitis, anterior segment neovascularization, glaucoma, and cataract are all later complications. Burns at the limbus carry a particularly poor prognosis because of potential ischemia and growth of neovascular tissue.

132 C) Topical steroids are used long-term to decrease the inflammatory response.

     Copious irrigation should be started immediately. Débridement of necrotic conjunctiva and particulate matter should be performed as they may harbor more chemical. pH testing of the conjunctival fornices is helpful during and after irrigation. Patching or bandage contact lens may be used to aid in healing epithelium with antibiotic prophylaxis. Topical steroids are useful to suppress the inflammatory response; however, their use should be limited to the first 7 days after injury as they may potentiate the action of collagenases leading to continued stromal loss. Cicatricial lid changes should be repaired before penetrating keratoplasty.

133 C) Pupillary exam

     Although an integral part of any eye examination, the pupillary examination would add little clinical information. The most likely diagnoses include episcleritis, conjunctivitis (allergic and viral), scleritis, anterior uveitis, and trauma.

134 C) Topical antibiotics

     The clinical entity pictured in Figure 10-57 is episcleritis. Although it is usually self-limited, if symptoms warrant, topical steroids, lubricants, or oral nonsteroidals are reasonable therapies. Topical antibiotics are not necessary or helpful given the noninfectious nature of the process. If purulent drainage or other signs of infection are present, culture and then appropriate coverage with antimicrobial agents are necessary.

135 B) Necrotizing scleritis with inflammation

     The most benign form of scleritis is diffuse anterior. In necrotizing scleritis with inflammation, 60% develop complications such as keratitis, cataract, uveitis, and scleral thinning, and 40% suffer visual loss. Many patients with this process die within a few years of diagnosis secondary to severe systemic autoimmune diseases, such as rheumatoid arthritis, polyarteritis nodosa, and Wegener granulomatosis.

136 D) Behçet disease

     Scleritis has been associated with infectious diseases (syphilis, tuberculosis, herpes zoster, and leprosy), autoimmune diseases (rheumatoid arthritis, Wegener granulomatosis, systemic lupus erythematosus, and polyarteritis nodosa), and metabolic diseases (gout).

137 A) Posterior sub-Tenon steroid injection

     Injection of steroids into the posterior sub-Tenon space is relatively contraindicated because it may increase the risk of scleral thinning and melting. Initial management is usually with an oral NSAID agent followed by systemic steroids and topical cyclosporine. Eventually, systemic immunosuppressives such as azathioprine or methotrexate may be necessary. While anterior injections of steroids have been used and advocated by some, they should be used with caution and avoided when incapable of direct visualization.

138 A) Shield ulcer

     Several ocular surface disorders result from an abnormality of the limbal stem cells. Acquired disorders include injuries, both chemical and thermal, contact lens–induced superior limbal keratoconjunctivitis, and Stevens–Johnson syndrome. Some hereditary etiologies include keratitis associated with multiple endocrine deficiencies and bilateral aniridia. Shield ulcers occur with limbal–vernal keratoconjunctivitis. No limbal stem cell deficiency is present with this condition.

139 D) Hypoventilation during general anesthesia

     Reduction of positive vitreous pressure is important during most intraocular surgeries, especially “open sky” procedures such as penetrating keratoplasty. Intraoperative maneuvers to reduce vitreous pressure include reducing vitreous volume by aspiration or dehydration (IV mannitol) and removing pressure on the globe. Hyperventilation, rather than hypoventilation, also can be used during cases under general anesthesia to decrease vitreous pressure.

140 D) Possible microbial contamination

     Corneal storage medium often contains colorimetric pH indicators. Such a color change indicates a change in pH, which may be consistent with microbial contamination.

141 C) Pseudophakic bullous keratopathy (PBK)

     Of those listed, PBK is the most frequent indication for keratoplasty in adults. This condition may decline in the future because of improvements in the design of anterior chamber and iris-fixated IOLs and in phacoemulsification techniques. Regrafts and keratoconus are also frequent indications for keratoplasty. Typically, endothelial kera- toplasty is used for PBK and penetrating or deep anterior lamellar keratoplasty is performed for keratoconus.

142 C) Peters anomaly

     Peters anomaly is the most frequent indication for penetrating keratoplasty in children.

143 A) Oversized grafts

     Penetrating keratoplasty in children can be very challenging. The eye wall is extremely flaccid, and scleral support is often crucial. Anterior bulging of the lens–iris diaphragm is common, and many surgeons prefer to use a small-sized graft to reduce this problem as well as to reduce the chance of peripheral synechiae formation. Frequent postoperative follow-up and early suture removal (as early as 2 to 4 weeks postoperatively in neonates) help reduce the incidence of ­neovascularization of the graft.

144 C) Slow or delayed healing

     Corneal transplants in children and young adults heal very quickly with sutures becoming vascularized and loosening within the first several months. Glaucoma and graft rejection are possible just as in adult transplants. In very young children, amblyopia presents a very real and difficult challenge. Fitting these children with contact lenses may restore vision more quickly and lessen the degree of amblyopia that develops. In addition to the previous complications, self-induced trauma is a frequent problem.

145 A) 90%

     Corneal graft survival is excellent with current techniques. The incidence is even higher for conditions such as keratoconus.

146 B) 65%

     Graft clarity is often higher for noninflamed eyes. Therefore, penetrating keratoplasty should be delayed until the eye is quiet (if possible).

147 C) 20%

     Overall, the chance of an endothelial graft rejection episode is 20% to 25% according to most studies. If the rejection is recognized early, intensive treatment may save the graft from failure.

148 C) ABO blood type incompatibility was shown to be a possible risk factor.

     The most interesting conclusion of this study was that even for high-risk keratoplasties, HLA tissue matching was neither clearly advantageous nor costeffective. The possibility also existed of a correlation of risk and ABO blood type incompatibility. Further study is needed to decide whether this is a necessary screening test.

149 D) All of the above

     Patients with connective tissue disorders, traumatic or hereditary epithelial surface disorders, poorly controlled blepharitis or keratoconjunctivitis sicca, and unrealistic expectations are also poor candidates.

150 B) 21 days

     Most contact lens wearers are very reluctant to discontinue use of their lenses for any significant amount of time. Stability of refraction and topography are important when deciding on a surgical plan. Most surgeons require at least 2 to 3 weeks of a contact lens “holiday” to verify stability. Some individuals require a longer period before they show stability and may need to be followed with serial topographies, keratometries, and refractions.

151 A) A trend toward hyperopia

     Figure 10-58 shows a patient with radial keratotomy.

152 B) Eight incisions

     The addition of eight incisions to an eight-incision radial keratotomy will often add little more myopic effect and may lead to more problems with corneal destabilization, wound gape, and, potentially, an increased risk of progressive hyperopia. Also, it is technically difficult to make such incisions sufficiently deep and uniform after placing the first eight.

153 B) 90°

     Most surgeons will rarely perform arcuate incisions greater than 90° because of decreased efficacy and increased instability of effect.

154 A) HLA-A, HLA-B, and HLA-DR matching the donor and recipient had no effect on overall graft survival.

     The Collaborative Corneal Transplantation Studies are a set of multicenter trials that investigated the efficacy of matching the donor–recipient HLAs on the incidence of graft rejection and graft survival in high-risk recipients undergoing penetrating keratoplasty. Matching HLA-A, HLA-B, and HLA-DR had no effect on overall graft survival or on the incidence of irreversible graft rejection. It is uncertain whether ABO blood group matching may reduce the risk of graft rejection. Matching donor–recipient age was not evaluated. These are being further studied in the ongoing Cornea Donor Study. Suturing technique and visual outcomes were not evaluated in the Collaborative Corneal Transplant Study.

155 D) Temporal

     The inferotemporal quadrant is the thinnest in most patients (38%). Of the provided choices, the thinnest quadrants (in descending order) are the temporal (28%), inferior (19%), nasal (11%), and superior (4%). Variation exists in individual patients.

156 B) Peripheral anterior synechia

     Figure 10-59 shows endothelial cell counts. The superior cell count shows a normal-­appearing endothelium. The inferior cell count shows abnormal endothelium. Unilateral endothelial cell abnormality is consistent with ICE syndrome. ICE syndrome is associated with unilateral corneal edema, peripheral anterior synechia, iris nevi, ectropion uveae, and other iris abnormalities. Fuchs endothelial dystrophy is demonstrated by bilateral guttata and corneal edema. Tram-track appearance on the corneal endothelium is associated with posterior polymorphous membranous dystrophy. Figure 10-74 shows an OCT image of peripheral anterior synechia in a patient with ICE.

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FIGURE 10-74

157 B) She has endothelial rejection.

     Figure 10-61 shows a penetrating keratoplasty. Horizontally dividing approximately the top third from the bottom third runs an endothelial rejection line called a Khodadoust line. The Khodadoust line is an arcade of advancing white blood cells that will cause severe endothelial damage unless the rejection is halted. While this patient may have had the transplant for keratoconus, there is no evidence of keratoconus in this picture.

158 D) A hyperopic shift is expected.

     Figure 10-61 shows a patient who is status-post Descemet Stripping Automated Endothelial Keratoplasty (DSAEK or DSEK). Superiorly in the anterior chamber an air bubble can be seen. DSEK is performed for endothelial failure. The air bubble keeps the transplant in place in the hours immediately after the surgery. If the patient is kept in a head-down position, the transplant may dislodge before it is allowed to firmly attach. Typically, patients are kept supine immediately after the DSEK procedure. Macular corneal dystrophy is a stromal dystrophy. A small hyperopic is common after DSEK.

159 A) Serum vitamin A levels

     Figure 10-62 shows a Bitot spot. Bitot spots are caused by vitamin A deficiency. They represent keratinization of the conjunctiva along with colonization with Corynebacterium xerosis. Vitamin A replacement is necessary to prevent the consequences of vitamin deficiency, including xerophthalmia, keratomalacia, nyctalopia, and blindness. Vitamin A deficiency mostly affects children in the developing world and may be fatal. Rheumatoid factor, thyroid levels, and antinuclear antibodies will not explain the conjunctival findings.

160 C) Tectonic graft

     Figure 10-63 shows a descemetocele. A descemetocele is a herniation of Descemet membrane. In this case, the overlying epithelium and stroma have been destroyed secondary to vitamin A deficiency and infection with Pseudomonas. Descemetoceles are at risk for perforation and may require tectonic corneal transplant. A bandage contact lens would do little to help this patient and is unlikely to fit because of the contour of protruding Descemet membrane. Topical NSAIDs have been associated with corneal melts and may exacerbate the descemetocele. An antiviral would be ineffective against this problem. Figure 10-75 shows a large diameter penetrating corneal transplant with an overlying amniotic membrane.

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FIGURE 10-75

161 D) Reassurance and observation

     The patient has a normal finding of a lymph vessel in her eye. She needs reassurance and observation especially if the vessel is otherwise asymptomatic. In cases of filariasis, a systemic helminthic workup is required. For example, in cases of Loa Loa filariasis in an infected patient from Africa, Loa Loa microfilariae will be found in the blood. The Loa Loa filarial worm can migrate to the conjunctiva and may be removed using surgical techniques.

162 B) Band keratopathy

     Figure 10-65 shows silicone oil in the anterior chamber. Silicone oil is placed in the eye for recalcitrant retinal detachments. It is associated with development of band keratopathy. Whether in the anterior chamber or not, silicone oil is sometimes associated with the development of band keratopathy. This patient is pseudophakic. The patient does not have a transplant.