Free ABO Retina and Vitreous Disorders Questions and Answers — Questions and Answers
Question 1: A 68-year-old male with a history of poorly controlled type 2 diabetes presents with a sudden, painless floater in his right eye. Fundus examination reveals neovascularization of the disc (NVD) greater than 1/3 disc area and a mild vitreous hemorrhage. According to the Diabetic Retinopathy Study (DRS), what is the most appropriate next step in management?
- Observation with strict glucose control.
- Intravitreal anti-VEGF injection alone.
- Prompt panretinal photocoagulation (PRP). (Correct answer)
- Focal laser photocoagulation to the macula.
Correct answer: Prompt panretinal photocoagulation (PRP).
The patient presents with high-risk characteristics (HRCs) of proliferative diabetic retinopathy (PDR), specifically NVD greater than 1/3 disc area and an associated vitreous hemorrhage. The landmark Diabetic Retinopathy Study (DRS) demonstrated that prompt panretinal photocoagulation (PRP) reduces the risk of severe vision loss by over 50% in eyes with HRCs. While anti-VEGF is also a treatment for PDR, PRP is the established gold standard based on the DRS findings for high-risk disease. Observation is inappropriate given the high risk of progression, and focal laser is for macular edema, not PDR.
Question 2: A 75-year-old female reports gradual blurring of her central vision and difficulty reading. Optical coherence tomography (OCT) reveals large, soft drusen and retinal pigment epithelium (RPE) atrophy. A fluorescein angiogram (FA) is performed. Which of the following FA findings would be most consistent with a diagnosis of neovascular (wet) age-related macular degeneration (AMD) rather than the non-neovascular (dry) form?
- Window defects corresponding to areas of RPE atrophy.
- Early hyperfluorescence with late leakage from an undefined source. (Correct answer)
- Blocking of fluorescence due to pigment clumping.
- Slow, late staining of drusen.
Correct answer: Early hyperfluorescence with late leakage from an undefined source.
Early hyperfluorescence that increases in intensity and spreads into the surrounding tissue (leakage) in the late phases of the angiogram is the hallmark of choroidal neovascularization (CNV), the defining feature of wet AMD. Window defects, blocking, and drusen staining are characteristic findings of dry AMD, representing RPE atrophy, pigment, and altered Bruch's membrane, respectively, but not active leakage from new vessels.
Question 3: Which of the following is considered the strongest predisposing risk factor for the development of a rhegmatogenous retinal detachment (RRD)?
- Lattice degeneration.
- Blunt ocular trauma.
- High myopia.
- Posterior vitreous detachment (PVD). (Correct answer)
Correct answer: Posterior vitreous detachment (PVD).
While high myopia, lattice degeneration, and trauma are all significant risk factors for RRD, the inciting event for the vast majority of RRDs is a posterior vitreous detachment (PVD). The dynamic vitreoretinal traction created during a PVD is what causes the retinal break (the 'rhegma'), allowing liquefied vitreous to enter the subretinal space. The other factors increase the likelihood that a PVD will result in a retinal break and subsequent detachment.
Question 4: A 65-year-old man presents to the emergency department with a 2-hour history of sudden, profound, and painless vision loss in his left eye. His visual acuity is hand motion. Fundus examination reveals diffuse retinal whitening, arteriolar attenuation, and a prominent 'cherry-red spot' in the macula. What is the most critical immediate step in this patient's management?
- Immediate referral for a comprehensive stroke workup. (Correct answer)
- Initiation of high-dose oral corticosteroids.
- Anterior chamber paracentesis.
- Scheduling for urgent vitrectomy.
Correct answer: Immediate referral for a comprehensive stroke workup.
The patient's presentation is classic for a central retinal artery occlusion (CRAO), which is considered an ocular emergency analogous to an acute ischemic stroke. Immediate referral to a stroke center for evaluation is critical to identify the embolic source and reduce the high risk of a subsequent, potentially fatal, cerebral or myocardial infarction. While treatments like paracentesis or ocular massage exist to dislodge the embolus, their efficacy is debated and secondary to the systemic evaluation. Steroids are for arteritic causes (like GCA), which must be evaluated but the stroke workup is the priority for all patients. Vitrectomy has no role in acute CRAO management.
Question 5: A 45-year-old patient is diagnosed with retinitis pigmentosa (RP). Which of the following findings constitutes the classic clinical triad observed on funduscopic examination for this condition?
- Optic disc drusen, macular edema, and peripheral hemorrhages.
- Choroidal folds, serous detachments, and vitritis.
- Arteriolar attenuation, waxy optic disc pallor, and bone-spicule pigmentation. (Correct answer)
- Cotton-wool spots, venous beading, and intraretinal microvascular abnormalities (IRMA).
Correct answer: Arteriolar attenuation, waxy optic disc pallor, and bone-spicule pigmentation.
The classic funduscopic triad of retinitis pigmentosa (RP) consists of retinal arteriolar attenuation, a waxy appearance of the optic disc pallor, and characteristic mid-peripheral intraretinal pigment migration in a bone-spicule pattern. The other answer choices describe findings associated with different retinal pathologies: option A can be seen in various conditions, option B suggests uveitis or a choroidal mass, and option D is characteristic of diabetic retinopathy.
Question 6: A 72-year-old patient with symptomatic vitreomacular traction is treated with an intravitreal injection of ocriplasmin. What is the primary mechanism of action of this drug?
- Inhibition of vascular endothelial growth factor (VEGF).
- Reduction of intraocular inflammation via corticosteroid action.
- Enzymatic cleavage of proteins at the vitreoretinal interface. (Correct answer)
- Osmotic dehydration of the vitreous gel.
Correct answer: Enzymatic cleavage of proteins at the vitreoretinal interface.
Ocriplasmin is a recombinant form of the human enzyme plasmin. Its mechanism of action is to enzymatically cleave structural proteins, such as fibronectin and laminin, which are key components of the vitreoretinal interface. This proteolysis dissolves the adhesion between the vitreous and the macula, releasing the traction. Anti-VEGF agents (A) are used for neovascular diseases, corticosteroids (B) reduce inflammation, and osmotic agents (D) are not used in this context.
Free ABO Retina and Vitreous Disorders Questions and Answers
A 68-year-old male with a history of poorly controlled type 2 diabetes presents with a sudden, painless floater in his right eye.
Fundus examination reveals neovascularization of the disc (NVD) greater than 1/3 disc area and a mild vitreous hemorrhage.
According to the Diabetic Retinopathy Study (DRS), what is the most appropriate next step in management?