Board Certified Ophthalmologist Board Certified Ophthalmologist Cornea and External Disease Questions and Answers 2 — Questions and Answers
Question 1: A patient presents with a unilateral, chronic, red eye with a strawberry-like papillary reaction on the upper tarsal conjunctiva. What is the most likely diagnosis?
- Giant papillary conjunctivitis (Correct answer)
- Vernal keratoconjunctivitis
- Trachoma
- Floppy eyelid syndrome
Correct answer: Giant papillary conjunctivitis
Giant papillary conjunctivitis is characterized by large cobblestone-like papillae on the upper tarsal conjunctiva, commonly associated with contact lens wear or ocular prostheses.
Question 2: Which layer of the cornea is most responsible for maintaining corneal transparency through its deturgescence function?
- Epithelium
- Bowman's layer
- Stroma
- Endothelium (Correct answer)
Correct answer: Endothelium
The corneal endothelium maintains stromal deturgescence through active Na+/K+-ATPase pump function, which is critical for corneal transparency.
Question 3: A 65-year-old patient develops a peripheral corneal ulcer with an overlying epithelial defect adjacent to an area of limbal injection. Workup reveals elevated ESR and positive c-ANCA. What is the most likely systemic association?
- Rheumatoid arthritis
- Granulomatosis with polyangiitis (Correct answer)
- Systemic lupus erythematosus
- Polyarteritis nodosa
Correct answer: Granulomatosis with polyangiitis
Peripheral ulcerative keratitis with positive c-ANCA is most strongly associated with granulomatosis with polyangiitis (formerly Wegener's granulomatosis).
Question 4: What is the most common causative organism of crystalline keratopathy?
- Staphylococcus aureus
- Streptococcus viridans (Correct answer)
- Pseudomonas aeruginosa
- Candida albicans
Correct answer: Streptococcus viridans
Streptococcus viridans is the most common organism causing infectious crystalline keratopathy, typically occurring in immunosuppressed corneas such as post-graft patients on chronic steroids.
Question 5: During pterygium surgery, which antimetabolite is most commonly used as an adjunct to reduce recurrence?
- 5-Fluorouracil
- Mitomycin C (Correct answer)
- Bevacizumab
- Cyclosporine
Correct answer: Mitomycin C
Mitomycin C is the most widely used adjunctive antimetabolite in pterygium surgery, applied intraoperatively to inhibit fibroblast proliferation and reduce recurrence.
Question 6: A newborn presents with bilateral cloudy corneas, tearing, and blepharospasm. Intraocular pressure is measured at 30 mmHg in both eyes. What is the most likely diagnosis?
- Peter's anomaly
- Birth trauma
- Primary congenital glaucoma (Correct answer)
- Congenital hereditary endothelial dystrophy
Correct answer: Primary congenital glaucoma
Primary congenital glaucoma presents with the classic triad of epiphora, photophobia, and blepharospasm along with corneal edema and elevated IOP in neonates.
Board Certified Ophthalmologist Board Certified Ophthalmologist Cornea and External Disease Questions and Answers 2
A patient presents with a unilateral, chronic, red eye with a strawberry-like papillary reaction on the upper tarsal conjunctiva.
What is the most likely diagnosis?