Free ABO Glaucoma Questions and Answers — Questions and Answers
Question 1: A 68-year-old patient with newly diagnosed primary open-angle glaucoma (POAG) has an IOP of 28 mmHg in both eyes and early glaucomatous optic neuropathy. What is the most appropriate initial medical therapy?
- Timolol
- Latanoprost (Correct answer)
- Brimonidine
- Dorzolamide
Correct answer: Latanoprost
Prostaglandin analogs are the first-line treatment for POAG due to their potent IOP-lowering effect, once-daily dosing, and favorable side-effect profile. They work by increasing uveoscleral outflow of aqueous humor.
Question 2: A 55-year-old female presents with sudden onset of severe eye pain, blurred vision, and a mid-dilated, non-reactive pupil. Gonioscopy of the fellow eye reveals a narrow, occludable angle. What is the most likely underlying mechanism?
- Pupillary block (Correct answer)
- Plateau iris syndrome
- Phacomorphic mechanism
- Neovascularization of the angle
Correct answer: Pupillary block
Pupillary block is the most common mechanism for primary angle-closure glaucoma. It occurs when aqueous humor is blocked from passing from the posterior to the anterior chamber at the level of the pupil, causing the iris to bow forward and occlude the trabecular meshwork.
Question 3: During gonioscopy, what is the most posterior structure visible in a normal, open angle?
- Schwalbe's line
- Trabecular meshwork
- Scleral spur
- Ciliary body band (Correct answer)
Correct answer: Ciliary body band
The structures of the angle from posterior to anterior are: Ciliary body band, Scleral spur, Trabecular meshwork, and Schwalbe's line. Therefore, the ciliary body band is the most posterior structure.
Question 4: A patient's Humphrey visual field test shows a dense scotoma that begins at the blind spot, arches over the macula, and ends at the horizontal raphe. What is this classic glaucomatous defect called?
- Nasal step
- Central scotoma
- Arcuate scotoma (Correct answer)
- Altitudinal defect
Correct answer: Arcuate scotoma
An arcuate scotoma, also known as a Bjerrum scotoma, is a classic visual field defect in glaucoma. It corresponds to damage to a bundle of retinal nerve fibers that arch from the optic disc around the macula.
Question 5: A 2-month-old infant presents with excessive tearing, light sensitivity, and eyelid squeezing. Examination reveals corneal clouding and an enlarged corneal diameter. This classic triad is most indicative of which condition?
- Congenital cataract
- Nasolacrimal duct obstruction
- Retinoblastoma
- Congenital glaucoma (Correct answer)
Correct answer: Congenital glaucoma
The classic triad of epiphora (tearing), photophobia (light sensitivity), and blepharospasm (eyelid squeezing) is highly suggestive of congenital glaucoma. The elevated IOP causes corneal edema (clouding) and stretching of the globe (buphthalmos).
Question 6: A 45-year-old patient with chronic anterior uveitis develops elevated IOP. Which mechanism is most likely responsible for the IOP spike during an active inflammatory episode?
- Trabeculitis (Correct answer)
- Pupillary block from posterior synechiae
- Steroid-induced IOP elevation
- Angle neovascularization
Correct answer: Trabeculitis
During active uveitis, inflammatory cells and proteins can clog the trabecular meshwork, a condition known as trabeculitis. This obstruction of the aqueous outflow pathway leads to an increase in intraocular pressure.
Question 7: A patient who underwent a trabeculectomy 2 months ago presents with a low IOP of 4 mmHg, a shallow anterior chamber, and choroidal folds on fundus examination. What is the most likely diagnosis?
- Blebitis
- Malignant glaucoma
- Hypotony maculopathy (Correct answer)
- Encapsulated bleb
Correct answer: Hypotony maculopathy
Hypotony maculopathy is a condition characterized by low IOP leading to chorioretinal folds, optic disc swelling, and decreased vision. It is a known complication of glaucoma filtration surgery, often resulting from over-filtration or a bleb leak.
Free ABO Glaucoma Questions and Answers
A 68-year-old patient with newly diagnosed primary open-angle glaucoma (POAG) has an IOP of 28 mmHg in both eyes and early glaucomatous optic neuropathy.
What is the most appropriate initial medical therapy?