Diseases of the Retina — MCQs

Diseases of the Retina Indian Medical PG Practice Questions and MCQs

Question 321: What is the most common etiology of recurrent vitreous hemorrhage in a young patient?

A. Trauma
B. Peripheral detachment of retina
C. Eales disease (Correct Answer)
D. Central retinal artery occlusion

Explanation: **Explanation:** **Eales disease** is the most common cause of recurrent vitreous hemorrhage in young adults (typically males aged 20–40) in the Indian subcontinent. It is an idiopathic, inflammatory peripheral retinal perivasculitis (primarily affecting venules). The disease progresses through three stages: perivascular sheathing, peripheral retinal ischemia/non-perfusion, and finally, **neovascularization**. These fragile new vessels (usually at the junction of perfused and non-perfused retina) bleed easily into the vitreous, leading to sudden, painless vision loss. Its association with hypersensitivity to tuberculoprotein is a frequently tested high-yield point. **Why other options are incorrect:** * **Trauma:** While a common cause of a *single* episode of vitreous hemorrhage, it is less likely to cause spontaneous *recurrent* episodes unless associated with a specific structural complication like a retinal tear. * **Peripheral detachment of retina:** Retinal detachment (RD) usually presents with flashes (photopsia) and floaters. While a retinal tear can cause hemorrhage, the RD itself is a consequence or a co-finding, not the primary etiology for recurrent bleeding in this demographic. * **Central Retinal Artery Occlusion (CRAO):** This presents with sudden, profound, painless loss of vision and a "cherry-red spot." It is an ischemic event, not a hemorrhagic one, and is rare in young patients. **High-Yield Clinical Pearls for NEET-PG:** * **Classic Triad of Eales:** Perivasculitis (sheathing), peripheral non-perfusion, and neovascularization/vitreous hemorrhage. * **Treatment:** Peripheral scatter laser photocoagulation (to ablate ischemic areas) and occasionally anti-VEGF injections or vitrectomy. * **Differential:** Always rule out Tuberculosis and Sarcoidosis in suspected Eales cases. * **Most common cause of VH in elderly:** Proliferative Diabetic Retinopathy (PDR).

Question 322: 'Bull's eye' lesion in the macular region is seen in which of the following conditions?

A. Progressive cone dystrophy
B. Chloroquine maculopathy
C. Both progressive cone dystrophy and chloroquine maculopathy (Correct Answer)
D. None of the above

Explanation: **Explanation:** A **'Bull's eye' maculopathy** is a classic clinical sign characterized by a central island of pigmented foveal epithelium surrounded by a concentric ring of hypopigmentation (due to RPE atrophy), which is further encircled by a ring of normal pigmentation. **Why Option C is Correct:** The lesion is not pathognomonic for a single disease but is a shared feature of several retinal conditions: 1. **Chloroquine/Hydroxychloroquine Maculopathy:** This is the most common toxic cause. The drug binds to melanin in the RPE, leading to localized atrophy in a circular pattern around the fovea. 2. **Progressive Cone Dystrophy:** This is the most common inherited cause. It presents with a gradual loss of color vision and central acuity, often manifesting the Bull's eye pattern during the atrophic stage. **Analysis of Other Options:** * **Options A & B:** While both conditions individually cause a Bull's eye lesion, selecting only one would be incomplete. In NEET-PG, when two valid causes are presented alongside a "Both" option, the combined option is the most accurate choice. **Clinical Pearls for NEET-PG:** * **Differential Diagnosis (Mnemonic: C-S-A-G-E):** * **C:** **C**hloroquine/Hydroxychloroquine toxicity. * **S:** **S**targardt’s disease (occasionally). * **A:** **A**ge-related macular degeneration (atrophic). * **G:** **G**lycosidosis (certain metabolic storage diseases). * **E:** **E**pinal (Cone) dystrophy. * **Screening:** For patients on Hydroxychloroquine, the **10-2 Visual Field test** and **SD-OCT** (showing the "Flying Saucer" sign) are the current gold standards for early detection before the Bull's eye becomes visible on fundoscopy. * **Prognosis:** Once the Bull's eye lesion is visible clinically, the damage is usually irreversible, even if the offending drug is discontinued.

Question 323: Exudative retinal detachment occurs in which of the following conditions?

A. Myopia
B. Diabetes mellitus
C. Pregnancy induced hypertension (Correct Answer)
D. Trauma

Explanation: **Explanation:** **Exudative (Serous) Retinal Detachment (RD)** occurs when fluid accumulates in the subretinal space between the neurosensory retina and the retinal pigment epithelium (RPE) without any retinal break or traction. **Why Pregnancy-Induced Hypertension (PIH) is correct:** In severe PIH or Eclampsia, the primary pathology is **systemic vasospasm**. This leads to intense vasoconstriction of the choroidal arterioles, causing choroidal ischemia and subsequent damage to the RPE. When the RPE (the blood-retinal barrier) is compromised, fluid leaks from the choriocapillaris into the subretinal space, resulting in an exudative RD. This is typically bilateral and usually resolves spontaneously once blood pressure is controlled postpartum. **Why the other options are incorrect:** * **Myopia:** High myopia is strongly associated with **Rhegmatogenous RD**, caused by peripheral retinal degenerations (like lattice degeneration) leading to retinal holes or tears. * **Diabetes Mellitus:** Proliferative Diabetic Retinopathy (PDR) leads to fibrovascular proliferation. The contraction of these membranes causes **Tractional RD**. * **Trauma:** Ocular trauma most commonly causes **Rhegmatogenous RD** (via retinal dialyses or tears) or occasionally tractional RD due to vitreous hemorrhage and scarring. **High-Yield Clinical Pearls for NEET-PG:** * **Rhegmatogenous RD:** Most common type; characterized by a "break" (hole/tear) and "Shifting Fluid" is **absent**. * **Exudative RD:** Key feature is **Shifting Fluid** (fluid moves with gravity). Other causes include Vogt-Koyanagi-Harada (VKH) syndrome, posterior scleritis, and choroidal tumors. * **Tractional RD:** Characterized by a "concave" configuration and restricted mobility; "Shifting Fluid" is **absent**.

Question 324: The retina is embryologically derived from which of the following germ layers?

A. Surface ectoderm
B. Neural ectoderm (Correct Answer)
C. Mesoderm
D. Endoderm

Explanation: **Explanation:** The eye is a complex organ derived from three primary sources: surface ectoderm, neural ectoderm, and mesoderm (including neural crest cells). **Why Neural Ectoderm is Correct:** The retina develops from the **optic vesicle**, which is an outgrowth of the **forebrain (diencephalon)**. As the optic vesicle invaginates to form the double-layered **optic cup**, the outer layer becomes the **Retinal Pigment Epithelium (RPE)** and the inner layer becomes the **Neurosensory Retina**. Since the forebrain is a derivative of the neural tube, the retina is strictly a **neural ectoderm** derivative. Other structures from this layer include the optic nerve, the posterior epithelium of the iris, and the ciliary body muscles (sphincter and dilator pupillae). **Analysis of Incorrect Options:** * **A. Surface Ectoderm:** This layer gives rise to the **lens**, the corneal epithelium, the lacrimal apparatus, and the eyelid skin. * **C. Mesoderm:** This contributes to the extraocular muscles, vascular endothelium, and the temporal side of the sclera. (Note: Most of the stroma of the eye, like the choroid and iris stroma, is derived from **Neural Crest Cells**). * **D. Endoderm:** The endoderm does not contribute to the development of the eye. **High-Yield Clinical Pearls for NEET-PG:** * **The "Two-Layer" Rule:** The potential space between the RPE and neurosensory retina (the intraretinal space) is where **Retinal Detachment** occurs. * **Optic Nerve:** It is technically a tract of the CNS, not a peripheral nerve, which is why it is myelinated by **oligodendrocytes** rather than Schwann cells. * **Muscle Exception:** The sphincter and dilator pupillae are the only muscles in the body derived from **neural ectoderm** (most muscles are mesodermal).

Question 325: The fundus photograph shown is characteristic of which of the following conditions?

A. Stargardt disease
B. Best disease (Correct Answer)
C. Fundus flavimaculatus
D. Stickler syndrome

Explanation: ***Best disease*** - Characterized by the pathognomonic **"egg-yolk" vitelliform macular lesion** that appears as a bright yellow, round deposit in the **macula**. - Associated with mutations in the **BEST1 gene** and shows characteristic **reduced Arden ratio** on electrooculography (EOG). *Stargardt disease* - Presents with **pisciform (fish-shaped) flecks** throughout the posterior pole, not a single egg-yolk lesion. - Caused by **ABCA4 gene mutations** and shows **dark choroid sign** on fluorescein angiography due to lipofuscin accumulation. *Fundus flavimaculatus* - Features multiple **yellow-white flecks** scattered across the fundus, similar to Stargardt disease pattern. - Also caused by **ABCA4 mutations** and lacks the characteristic single vitelliform lesion of Best disease. *Stickler syndrome* - A **connective tissue disorder** that may cause retinal detachment and vitreoretinal degeneration. - Does **not produce characteristic macular lesions** and is associated with systemic features like cleft palate and joint hypermobility.

Question 326: A 65-year-old man presents with metamorphopsia. On examination, he has yellow deposits subretinal near the macula in both eyes. The rest of the fundus is normal. What is the probable diagnosis?

A. Hypertensive retinopathy
B. Age-related macular degeneration (Correct Answer)
C. Eales disease
D. Diabetic retinopathy

Explanation: ### Explanation **Correct Answer: B. Age-related macular degeneration (ARMD)** The clinical presentation is classic for **Age-Related Macular Degeneration**. The key diagnostic features in this case are: 1. **Age:** ARMD typically affects patients over 50–60 years. 2. **Metamorphopsia:** This distortion of vision (straight lines appearing wavy) is a hallmark symptom of macular pathology. 3. **Drusen:** The "yellow subretinal deposits" described are **Drusen**, which are accumulations of extracellular material between the retinal pigment epithelium (RPE) and Bruch’s membrane. Their presence near the macula is the earliest clinical sign of ARMD. --- ### Why the other options are incorrect: * **A. Hypertensive Retinopathy:** Characterized by generalized arteriolar narrowing, AV nipping, flame-shaped hemorrhages, and **Cotton Wool spots**. While "Hard Exudates" (yellowish) can occur, they usually form a macular star and are associated with vascular changes not mentioned here. * **C. Eales Disease:** An idiopathic peripheral perivasculitis (usually affecting young males). It presents with peripheral neovascularization and recurrent **vitreous hemorrhage**, not subretinal yellow deposits at the macula. * **D. Diabetic Retinopathy:** Features include microaneurysms, dot-and-blot hemorrhages, and hard exudates. However, these are typically accompanied by vascular abnormalities and occur in the setting of diabetes, whereas Drusen are specific to the aging RPE. --- ### High-Yield Clinical Pearls for NEET-PG: * **Amsler Grid:** The bedside test used to monitor metamorphopsia in ARMD patients. * **Dry vs. Wet ARMD:** Dry ARMD (90%) is characterized by Drusen and geographic atrophy. Wet ARMD (10%) involves **Choroidal Neovascularization (CNVM)** and is treated with **Anti-VEGF** injections (e.g., Ranibizumab, Bevacizumab). * **AREDS 2 Formula:** A specific combination of antioxidants (Vitamin C, E, Lutein, Zeaxanthin, Zinc) used to slow the progression of intermediate/advanced dry ARMD. * **Fundus Fluorescein Angiography (FFA):** The gold standard for identifying the "classic" or "occult" leakage in wet ARMD.

Question 327: Which gas is used for retinal tamponade?

A. Sulfur hexafluoride (SF6) (Correct Answer)
B. Ethylene oxide
C. Nitrous oxide
D. Carbon dioxide (CO2)

Explanation: **Explanation:** In vitreoretinal surgery, **intraocular gases** are used as a "tamponade" to provide surface tension that holds the retina in place against the retinal pigment epithelium (RPE), allowing for the closure of retinal breaks and the reabsorption of subretinal fluid. **1. Why Sulfur hexafluoride (SF6) is correct:** SF6 is a colorless, odorless, non-toxic, and inert gas. When injected into the eye, it acts as an **expansile gas**. It is insoluble in water, allowing it to remain in the eye for approximately **10–14 days**. This duration is sufficient for a permanent chorioretinal adhesion (scar) to form following laser or cryotherapy. Other commonly used gases include Perfluoropropane (C3F8), which lasts longer (55–65 days). **2. Why the other options are incorrect:** * **Ethylene oxide:** This is a potent chemical used for the **sterilization** of medical equipment. It is highly toxic and cannot be used inside the human body. * **Nitrous oxide (N2O):** Used as an **inhalation anesthetic**. It is highly soluble in blood and would be absorbed from the eye within minutes, making it useless as a tamponade. (Note: N2O should be discontinued during surgery before gas injection to prevent rapid expansion of the intraocular bubble). * **Carbon dioxide (CO2):** This gas is rapidly absorbed by the tissues and blood; it lacks the surface tension and longevity required for retinal stabilization. **High-Yield Clinical Pearls for NEET-PG:** * **Expansion:** SF6 expands to **2x** its volume; C3F8 expands to **4x** its volume. * **Positioning:** Patients must maintain a specific **prone (face-down) position** post-operatively so the buoyant gas bubble rises to press against the retinal break. * **Contraindication:** Patients with intraocular gas must **avoid air travel** and nitrous oxide anesthesia, as the change in atmospheric pressure can cause the gas to expand, leading to a dangerous rise in intraocular pressure (secondary glaucoma).

Question 328: A 7-year-old child presents with left exotropia. The right eye has 6/6 vision with a normal fundus. The left eye has only close hand movements, with subretinal yellow exudates, retinal detachment, and telangiectatic vessels. What is the diagnosis?

A. Sympathetic ophthalmia
B. Coats disease (Correct Answer)
C. Retinopathy of prematurity (ROP)
D. Familial exudative vitreous retinopathy (FEVR)

Explanation: **Explanation:** The clinical presentation of a young child with unilateral vision loss (presenting as exotropia), **telangiectatic retinal vessels**, and massive **subretinal yellow exudates** (due to lipid deposition) is the classic hallmark of **Coats Disease**. **Why Coats Disease is correct:** Coats disease is an idiopathic, non-hereditary condition characterized by abnormal telangiectatic and aneurysmal retinal vessels ("light bulb" appearance). These leaky vessels lead to extensive subretinal exudation, which can progress to an exudative retinal detachment. It typically affects young males (85%) and is almost always **unilateral**, distinguishing it from other pediatric retinal pathologies. **Why other options are incorrect:** * **Sympathetic Ophthalmia:** This is a bilateral granulomatous panuveitis following a penetrating injury or surgery to one eye (the "exciting" eye). There is no history of trauma or signs of uveitis here. * **Retinopathy of Prematurity (ROP):** ROP is typically bilateral and occurs in premature infants with a history of oxygen therapy. It is characterized by fibrovascular proliferation at the ridge between vascular and avascular retina, not massive subretinal lipid exudation. * **Familial Exudative Vitreous Retinopathy (FEVR):** While it shares features of peripheral non-perfusion, FEVR is usually **bilateral**, hereditary (autosomal dominant), and characterized by vitreoretinal traction rather than primary massive exudation. **High-Yield Clinical Pearls for NEET-PG:** * **Gender:** Predominantly affects males (85%). * **Laterality:** 90-95% of cases are **unilateral**. * **Leukocoria:** Coats disease is a major differential diagnosis for Retinoblastoma (pseudoglioma). * **Pathognomonic sign:** "Light bulb" telangiectasia and cholesterol crystals in the subretinal fluid. * **Treatment:** Laser photocoagulation or cryotherapy to the leaking vessels.

Question 329: Macular involvement is common in which of the following infections?

A. Toxoplasma
B. Malaria (Correct Answer)
C. Cytomegalovirus (CMV)
D. Syphilis

Explanation: **Explanation:** The correct answer is **Malaria**. While many systemic infections can affect the retina, **Malarial Retinopathy** is a hallmark of severe/cerebral malaria (caused by *Plasmodium falciparum*) and is characterized by a high predilection for the **macula**. **Why Malaria is Correct:** The pathophysiology involves the sequestration of parasitized red blood cells in the retinal microvasculature, leading to cytoadherence and capillary occlusion. This results in: 1. **Retinal Whitening:** Ischemic whitening that is most prominent in the **macular and paramacular areas**, often sparing the foveola. 2. **Vessel Changes:** "Orange" or "white" vessels due to dehemoglobinization. 3. **Malarial Retinal Hemorrhages:** Often have white centers (resembling Roth spots). The presence of macular whitening is a strong prognostic indicator of neurological involvement and mortality in children. **Why other options are incorrect:** * **Toxoplasma:** Typically presents as a focal "headlight in the fog" chorioretinitis. While it can occur at the macula, it is not defined by generalized macular involvement in the same systemic context as malarial retinopathy. * **CMV:** Characteristically presents as "pizza-pie" or "crushed tomato" retinopathy with extensive necrosis and hemorrhage, usually following the vascular arcades rather than being specifically localized to the macula. * **Syphilis:** Known as the "Great Imitator," it most commonly presents as posterior placoid chorioretinitis or generalized uveitis, but is not the primary association for specific macular involvement among these choices. **Clinical Pearls for NEET-PG:** * **Malarial Retinopathy Triad:** Retinal whitening (macular), vessel changes, and retinal hemorrhages. * **Prognostic Value:** Retinopathy is the most specific indicator of **Cerebral Malaria**. * **Differential:** Always differentiate Malarial whitening from **Cherry Red Spot** (seen in CRAO, Tay-Sachs, etc.), where the macula is pale but the fovea remains red.

Question 330: Epidemic dropsy is characterised by all EXCEPT:

A. Disc-edema
B. Hard-exudates (Correct Answer)
C. Peri-retinal haemorrhage
D. Tortous-retinal vessels

Explanation: **Explanation:** **Epidemic Dropsy** is a clinical condition caused by the ingestion of mustard oil adulterated with **Argemone mexicana** oil. The toxic alkaloid involved is **Sanguinarine**, which inhibits the Na⁺-K⁺ ATPase pump, leading to increased capillary permeability and widespread vasodilation. **Why "Hard Exudates" is the correct answer:** Hard exudates are composed of lipoprotein deposits resulting from chronic vascular leakage (commonly seen in Diabetic Retinopathy). In Epidemic Dropsy, the ocular involvement is characterized by **acute vascular congestion** and hyperpermeability rather than chronic lipid deposition. Therefore, hard exudates are not a feature of this condition. **Analysis of other options:** * **Disc Edema (A):** Increased capillary permeability and venous congestion often lead to bilateral optic disc edema (papilledema). * **Peri-retinal Hemorrhage (C):** The toxic effect of Sanguinarine on the vessel walls causes them to leak or rupture, leading to superficial and deep retinal hemorrhages. * **Tortuous Retinal Vessels (D):** Marked dilatation and tortuosity of retinal veins occur due to the generalized vasodilatory effect of the toxin. **Clinical Pearls for NEET-PG:** 1. **Glaucoma:** The most characteristic ocular feature is **bilateral, secondary Open Angle Glaucoma** (due to increased production of aqueous humor and accumulation of prostaglandins). 2. **Key Symptom:** Unlike primary glaucoma, the intraocular pressure (IOP) is often very high, but the eye remains relatively quiet (no congestion). 3. **Systemic Features:** Bilateral pitting edema of the lower limbs, cardiac failure, and "Sanguinarine spots" (telangiectasia on the skin). 4. **Treatment:** Immediate withdrawal of the adulterated oil; medical management of glaucoma (though it is often refractory to conventional treatment).

Practice by Chapter

Retinal Anatomy and Physiology

Practice Questions

Age-Related Macular Degeneration

Practice Questions

Diabetic Retinopathy

Practice Questions

Retinal Vascular Diseases

Practice Questions

Retinal Detachment

Practice Questions

Hereditary Retinal Dystrophies

Practice Questions

Inflammatory Retinal Diseases

Practice Questions

Retinal Tumors

Practice Questions

Retinopathy of Prematurity

Practice Questions

Retinal Imaging Techniques

Practice Questions

Intravitreal Pharmacotherapy

Practice Questions

Vitreoretinal Surgery

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free