Free Board Certified Ophthalmologist Retina and Vitreous Diseases Questions and Answers — Questions and Answers
Question 1: A 68-year-old patient with non-exudative age-related macular degeneration (AMD) asks about nutritional supplements. According to the AREDS2 study, which formulation is most appropriate to recommend for reducing the risk of progression to advanced AMD?
- Vitamin C, Vitamin E, beta-carotene, zinc, and copper.
- Lutein, zeaxanthin, omega-3 fatty acids, zinc, and copper.
- Vitamin C, Vitamin E, lutein, zeaxanthin, zinc, and copper. (Correct answer)
- High-dose Vitamin E, beta-carotene, and omega-3 fatty acids.
Correct answer: Vitamin C, Vitamin E, lutein, zeaxanthin, zinc, and copper.
The AREDS2 study found that a formulation containing Vitamin C (500 mg), Vitamin E (400 IU), lutein (10 mg), zeaxanthin (2 mg), zinc (80 mg), and copper (2 mg) reduced the risk of progression to advanced AMD. The study recommended replacing beta-carotene with lutein and zeaxanthin because beta-carotene was linked to an increased risk of lung cancer in smokers and the new combination provided an additional reduction in risk. Omega-3 fatty acids were studied but did not show a significant additional benefit.
Question 2: A 55-year-old male presents with a one-week history of painless, progressive central vision loss in his right eye. Fundus examination reveals a localized serous detachment of the neurosensory retina in the macula. Optical coherence tomography (OCT) confirms subretinal fluid. Fluorescein angiography shows a focal point of leakage. What is the most appropriate initial management for this patient with acute central serous chorioretinopathy (CSC)?
- Immediate intravitreal anti-VEGF injection.
- Observation for 3-4 months with lifestyle modification advice. (Correct answer)
- Focal laser photocoagulation to the leakage point.
- Half-dose photodynamic therapy (PDT).
Correct answer: Observation for 3-4 months with lifestyle modification advice.
For most cases of acute central serous chorioretinopathy, the standard initial management is observation, as many cases resolve spontaneously within 3 to 4 months. Patients are often counseled on modifying risk factors such as stress. Active interventions like laser photocoagulation or PDT are typically reserved for chronic or persistent cases, or in specific situations where a patient has occupational needs for rapid vision recovery.
Question 3: Which of the following is the primary mechanism of action for intravitreal anti-VEGF agents in the treatment of macular edema secondary to a central retinal vein occlusion (CRVO)?
- Inducing posterior vitreous detachment.
- Reducing intraocular pressure.
- Decreasing vascular permeability and leakage. (Correct answer)
- Dissolving the thrombus at the optic nerve head.
Correct answer: Decreasing vascular permeability and leakage.
In retinal vein occlusion, ischemia leads to the upregulation of Vascular Endothelial Growth Factor (VEGF), which increases vascular permeability, causing macular edema. Anti-VEGF agents work by binding to and inhibiting VEGF, thereby reducing the leakage from retinal capillaries and decreasing the macular edema, which is the primary cause of vision loss.
Question 4: A 62-year-old phakic patient presents with an uncomplicated rhegmatogenous retinal detachment involving a single horseshoe tear at the 11 o'clock position with subretinal fluid extending just posterior to the equator but not involving the macula. Which of the following surgical options is generally considered the LEAST invasive procedure with a reasonable success rate for this specific presentation?
- Scleral buckle.
- Pars plana vitrectomy with gas tamponade.
- Pneumatic retinopexy. (Correct answer)
- Laser retinopexy alone.
Correct answer: Pneumatic retinopexy.
Pneumatic retinopexy is a minimally invasive procedure best suited for uncomplicated retinal detachments with retinal breaks located in the superior portion of the retina (typically between 8 and 4 o'clock). It involves injecting a gas bubble into the vitreous cavity to tamponade the retinal break, followed by cryotherapy or laser to create a permanent adhesion. While vitrectomy and scleral buckling are also effective, they are more invasive procedures. Laser alone is insufficient to reattach the retina.
Question 5: A patient undergoes successful surgery for a rhegmatogenous retinal detachment but develops recurrent detachment 6 weeks later. The examination reveals fixed retinal folds and subretinal strands, characteristic of proliferative vitreoretinopathy (PVR). Which cell type is considered the primary driver of membrane formation in PVR?
- Müller cells
- Retinal pigment epithelial (RPE) cells (Correct answer)
- Vascular endothelial cells
- Pericytes
Correct answer: Retinal pigment epithelial (RPE) cells
The pathogenesis of proliferative vitreoretinopathy (PVR) involves the dispersion of retinal pigment epithelial (RPE) cells into the vitreous cavity through the retinal break. These RPE cells undergo an epithelial-to-mesenchymal transition (EMT), transforming into fibroblast-like cells that proliferate and form contractile membranes on the retinal surfaces, leading to retinal traction and redetachment.
Question 6: According to the Diabetic Retinopathy Clinical Research Network (DRCR.net) Protocol S, for patients with proliferative diabetic retinopathy (PDR), how did visual acuity outcomes at 2 years for treatment with intravitreal ranibizumab compare to panretinal photocoagulation (PRP)?
- Ranibizumab was superior to PRP.
- Ranibizumab was non-inferior to PRP. (Correct answer)
- PRP was superior to ranibizumab.
- The study was inconclusive regarding visual acuity.
Correct answer: Ranibizumab was non-inferior to PRP.
The DRCR.net Protocol S demonstrated that intravitreal ranibizumab was non-inferior to panretinal photocoagulation (PRP) for treating proliferative diabetic retinopathy with respect to visual acuity outcomes at 2 years. While the mean visual acuity was slightly better in the ranibizumab group, the primary outcome was non-inferiority. The ranibizumab group also experienced less peripheral visual field loss and had a lower rate of developing diabetic macular edema.
Free Board Certified Ophthalmologist Retina and Vitreous Diseases Questions and Answers
A 68-year-old patient with non-exudative age-related macular degeneration (AMD) asks about nutritional supplements.
According to the AREDS2 study, which formulation is most appropriate to recommend for reducing the risk of progression to advanced AMD?