ABO Ocular Disease & Pathology 5 — Questions and Answers
Question 1: A patient with myasthenia gravis presents with ptosis and diplopia that worsen with sustained upgaze and improve with rest. Which test is used to confirm the diagnosis at the bedside?
- Forced duction test
- Ice pack test (Correct answer)
- Cover-uncover test
- Maddox rod test
Correct answer: Ice pack test
Applying ice to a ptotic lid for 2 minutes reduces the ptosis in myasthenia gravis by slowing acetylcholinesterase activity at the neuromuscular junction.
Question 2: Haab's striae in the cornea of an infant indicate which diagnosis?
- Birth trauma (forceps delivery)
- Congenital glaucoma (buphthalmos) (Correct answer)
- Keratoconus
- Interstitial keratitis
Correct answer: Congenital glaucoma (buphthalmos)
Haab's striae are breaks in Descemet's membrane caused by elevated IOP stretching the infant eye in congenital glaucoma.
Question 3: Which finding best differentiates wet (neovascular) AMD from dry AMD on clinical exam?
- Drusen in the macula
- Subretinal fluid or hemorrhage at the macula (Correct answer)
- Pigmentary changes in the RPE
- Geographic atrophy of the RPE
Correct answer: Subretinal fluid or hemorrhage at the macula
Subretinal fluid or hemorrhage from CNV defines wet AMD; drusen and geographic atrophy are features of dry AMD.
Question 4: A patient with HIV and CD4 count <50 cells/µL presents with painless progressive peripheral visual field loss and 'pizza pie' fundus appearance. The most likely diagnosis is:
- Toxoplasma retinochoroiditis
- CMV retinitis (Correct answer)
- Progressive outer retinal necrosis
- Acute retinal necrosis
Correct answer: CMV retinitis
CMV retinitis classically produces hemorrhagic, necrotizing retinitis with a 'pizza pie' or 'cottage cheese and ketchup' fundus in severely immunocompromised HIV patients.
Question 5: A Hollenhorst plaque (cholesterol embolus) seen at an arteriolar bifurcation is most likely to originate from which location?
- The aortic valve
- The carotid artery (Correct answer)
- The left atrium
- The pulmonary vein
Correct answer: The carotid artery
Hollenhorst plaques are cholesterol crystals that typically originate from atheromatous plaques in the ipsilateral carotid artery.
Question 6: Sympathetic ophthalmia is a bilateral granulomatous uveitis that develops after:
- Herpes simplex virus reactivation
- Penetrating trauma or surgery to one eye (Correct answer)
- Long-standing uveitis in one eye
- Topical corticosteroid overuse
Correct answer: Penetrating trauma or surgery to one eye
Sympathetic ophthalmia is an autoimmune uveal inflammation of the fellow (sympathizing) eye following penetrating injury or intraocular surgery to the exciting eye.
Question 7: Which of the following is the gold standard imaging modality for detecting and monitoring glaucomatous retinal nerve fiber layer (RNFL) thinning?
- Fundus photography
- Fluorescein angiography
- Optical coherence tomography (OCT) (Correct answer)
- B-scan ultrasonography
Correct answer: Optical coherence tomography (OCT)
Spectral-domain OCT provides quantitative, high-resolution cross-sectional RNFL measurements and is the gold standard for detecting structural glaucomatous damage.
ABO Ocular Disease & Pathology 5
A patient with myasthenia gravis presents with ptosis and diplopia that worsen with sustained upgaze and improve with rest.
Which test is used to confirm the diagnosis at the bedside?