NEET-PG 2013 - Ophthalmology Practice Questions

Q: Which of the following statements about the c-wave in electroretinogram (ERG) is most accurate?

The 'c' wave is a slow positive wave.. ***The 'c' wave is a slow positive wave.*** - The **c-wave** in an ERG is generated by the **retinal pigment epithelium (RPE)** and is characterized by its **slow, positive deflection**. - It reflects the **hyperpolarization** of the RPE cells in response to light stimulation. *The 'c' wave is a negative wave.* - This statement is incorrect because the **c-wave** is consistently observed as a **positive deflection** in the ERG tracing. - A negative wave like the **a-wave** is generated by photoreceptor hyperpolarization, which is a different component. *The 'b' wave arises primarily from photoreceptors.* - The **b-wave** primarily arises from the **Müller cells** and **bipolar cells**, not directly from photoreceptors. - Photoreceptor activity is primarily reflected in the **a-wave**. *The 'a' wave is a positive wave.* - The **a-wave** is a **negative deflection** in the ERG, representing the **hyperpolarization of photoreceptors** in response to light. - It is the earliest component of the ERG waveform.

Q: Parachute lesions are associated with which of the following conditions?

Eale's disease. ***Eale's disease*** - **Eale's disease** is an idiopathic retinal perivasculitis affecting young males, characterized by recurrent vitreous hemorrhages. - In the context of this question (NEET-2013), the term "parachute lesions" refers to the characteristic pattern of hemorrhages seen in Eale's disease. - The disease features retinal periphlebitis, capillary non-perfusion, and neovascularization leading to vitreous hemorrhage. - **Note:** The term "parachute hemorrhages" in broader ophthalmology typically describes preretinal/subhyaloid hemorrhages that settle inferiorly (boat-shaped), more commonly seen in proliferative diabetic retinopathy. *Diabetes* - **Diabetic retinopathy** presents with microaneurysms, dot-blot hemorrhages, hard exudates, cotton-wool spots, and neovascularization. - While proliferative diabetic retinopathy can cause preretinal "parachute-shaped" hemorrhages (boat-shaped hemorrhages that settle inferiorly), this is not the association being tested in this NEET-2013 question. - The specific context of this exam question associates the term with Eale's disease. *Sickle cell anemia* - **Sickle cell retinopathy** features characteristic sea-fan neovascularization in the peripheral retina. - Can cause salmon-patch hemorrhages, black sunburst lesions, and angioid streaks. - While vitreous hemorrhage can occur, "parachute lesions" is not standard terminology for sickle cell retinopathy manifestations. *None of the options* - This option is incorrect because **Eale's disease** is the correct answer according to the NEET-2013 exam key.

Q: What condition is characterized by an "umbrella" configuration on fluorescein angiography?

Central serous retinopathy. ***Central serous retinopathy*** - The "umbrella" or "smokestack" configuration on **fluorescein angiography** is a classic finding in central serous retinopathy, indicating leakage of dye creating a mushroom-shaped plume. - This leakage originates from the **retinal pigment epithelium (RPE)** into the subretinal space, causing serous detachment of the neurosensory retina. *Retinitis pigmentosa* - Characterized by **progressive photoreceptor degeneration** and **pigmentary changes** in the retina, often described as "bone-spicule" pigmentation. - Fluorescein angiography in retinitis pigmentosa typically shows **atrophy** and **window defects**, not an umbrella pattern of leakage. *Rhegmatogenous retinal detachment* - Involves a **full-thickness break in the retina** that allows vitreous fluid to pass into the subretinal space, causing the retina to detach. - Fluorescein angiography is generally not used for primary diagnosis and would not show an umbrella pattern, but rather **non-perfusion** or vascular changes in the detached area. *Eale's disease* - A rare **idiopathic obliterative periphlebitis** primarily affecting the retinal veins, leading to recurrent vitreous hemorrhages and retinal neovascularization. - Fluorescein angiography would reveal **vascular sheathing**, **non-perfusion**, and **neovascularization**, which are distinct from the umbrella configuration.

Q: Snow banking is seen in?

Intermediate uveitis. ***Intermediate uveitis*** - **Snow banking** refers to the accumulation of inflammatory exudates on the surface of the **pars plana** and **ora serrata**, a characteristic sign of intermediate uveitis. - This condition primarily affects the **vitreous** and peripheral retina, often leading to symptoms like **floaters** and **decreased vision**. *White coat syndrome* - This refers to a phenomenon where a patient's **blood pressure is elevated** in a clinical setting due to anxiety, but is normal outside of the medical environment. - It has no ophthalmic manifestations or association with "snow banking." *Eales syndrome* - This is an idiopathic inflammatory condition primarily affecting the **peripheral retinal vasculature**, leading to **vasculitis**, occlusion, and neovascularization. - While it can cause vitreous hemorrhage, it does not typically present with "snow banking" as a primary feature. *Diabetic kidney disease* - This is a complication of **diabetes mellitus** characterized by damage to the small blood vessels in the kidneys, leading to impaired kidney function. - It is a systemic condition with no direct relationship to ocular "snow banking" or uveitis.

Q: Which of the following is not a cause of exudative retinal detachment?

High myopia. ***High myopia*** - **High myopia** is a risk factor for **rhegmatogenous retinal detachment**, which is caused by a retinal break, not by fluid accumulation from a vascular or inflammatory process. - In rhegmatogenous detachment, vitreous fluid passes through the break into the subretinal space, separating the **neurosensory retina** from the **retinal pigment epithelium**. *Toxemia of pregnancy* - **Toxemia of pregnancy** (preeclampsia/eclampsia) can cause **exudative retinal detachment** due to choroidal ischemia and dysfunction of the retinal pigment epithelium, leading to fluid leakage. - The elevated **blood pressure** and systemic vascular changes impair choroidal perfusion, resulting in serous fluid accumulation beneath the retina. *Scleritis* - **Posterior scleritis** can lead to **exudative retinal detachment** by causing inflammation and edema of the choroid and sclera, which in turn compromises the integrity of the retinal pigment epithelium. - The inflammatory process increases vascular permeability, allowing fluid to leak into the subretinal space. *Central serous retinopathy* - **Central serous retinopathy** is a classic example of **exudative retinal detachment**, characterized by serous fluid accumulation under the macula. - This occurs due to dysfunction or a break in the **retinal pigment epithelium**, often associated with stress and corticosteroid use, leading to fluid leakage from the choroid.

Q: The most common cause of vitreous hemorrhage in adults is

Diabetes. ***Diabetes*** - **Proliferative diabetic retinopathy (PDR)** leads to the formation of new, fragile blood vessels (neovascularization) on the retinal surface or optic disc. - These new vessels are prone to bleeding into the **vitreous cavity**, making diabetes the most common cause of vitreous hemorrhage in adults. *Retinal hole* - A retinal hole or tear can lead to **rhegmatogenous retinal detachment** but does not commonly cause significant vitreous hemorrhage on its own. - While a tear can sometimes be associated with a small amount of hemorrhage, it is not the MOST common cause of widespread vitreous bleeding. *Trauma* - **Ocular trauma**, such as blunt or penetrating injuries, can certainly cause vitreous hemorrhage due to direct damage to retinal or choroidal blood vessels. - However, in the general adult population, **systemic diseases** like diabetes are statistically more frequent causes of spontaneous vitreous hemorrhage than acute trauma. *Hypertension* - Severe **hypertensive retinopathy** can cause retinal hemorrhages, microaneurysms, and cotton wool spots, but it typically does not lead to large-volume vitreous hemorrhage. - While hypertension can contribute to the severity of other retinal conditions, it is not the primary direct cause of vitreous hemorrhage itself.

Q: Birdshot retinopathy is characterized by all except?

Unilateral. ***Unilateral*** - **Birdshot retinopathy** is characteristically a **bilateral** inflammatory condition affecting both eyes, even if the onset may be asymmetric. - The disease involves widespread inflammation of the **choroid** and **retina**, typically presenting in both eyes simultaneously or sequentially. - Unilateral presentation would be highly atypical and should prompt consideration of alternative diagnoses. *Common in females* - Birdshot retinopathy shows a **clear female predominance**, with approximately **2-3 times more females affected than males** (60-75% of cases). - This demographic trend is a well-established feature of the disease. - However, it does occur in both sexes and is still considered characteristic of the condition. *HLA-A29 positive* - A strong association with the **HLA-A29 allele** is a hallmark of birdshot retinopathy, found in **over 95% of affected individuals**. - This genetic marker is highly specific and often used to support the diagnosis. - HLA-A29 testing is considered part of the diagnostic workup. *Creamy yellow spots* - The presence of characteristic **creamy yellow-white choroidal lesions**, resembling birdshot scatter, is a defining clinical feature. - These lesions are typically located in the **mid-peripheral and posterior fundus**, distributed radially around the optic disc. - The "birdshot" appearance refers to the scattered pattern resembling shotgun pellet distribution.

Q: The earliest change noticed in hypertensive retinopathy is:

Arteriolar spasm. ***Arteriolar spasm*** - **Arteriolar spasm** is the **earliest functional change** and is characterized by increased vascular tone in response to elevated blood pressure. - This spasm is a dynamic process and often leads to **narrowing of the retinal arterioles**, which can be observed during fundoscopic examination. *Soft exudate* - **Soft exudates**, also known as **cotton wool spots**, represent areas of **ischemic retinal nerve fiber layer** damage due to obstruction of precapillary arterioles. - These are typically seen in later stages of hypertensive retinopathy, indicating more significant vascular damage and ischemia. *Venospasm* - **Venospasm**, or narrowing of retinal veins, is **not a primary or early finding** in hypertensive retinopathy. - While venous changes like tortuosity can occur, arterial changes dominate the early pathogenesis. *Hard exudate* - **Hard exudates** are yellow-white deposits of **lipid and protein** that leak from damaged capillaries, often indicative of chronic retinal edema and incompetent blood-retinal barrier. - These usually appear in **more advanced stages** of hypertensive retinopathy and are not considered the earliest change.

Q: What is the thinnest portion of the sclera?

Posterior to the rectus muscle insertion. ***Posterior to the rectus muscle insertion*** - The sclera is thinnest immediately **posterior to the insertion of the rectus muscles**, where it is about 0.3 mm thick. - This area is clinically relevant as it is a common site for globe rupture during trauma. *Anterior to the rectus muscle insertion* - The sclera is relatively thick in this region, measuring around **0.6 mm thick**. - It provides robust support and attachment for the rectus muscles. *At the posterior pole* - At the posterior pole, the sclera is the **thickest**, reaching about 1.0 mm, especially around the optic nerve. - This thickness is necessary to protect the delicate neural structures exiting the eye. *At the limbus* - The sclera-corneal junction, or **limbus**, has an intermediate thickness, around **0.8 mm**. - This area is critical for surgical procedures but is not the thinnest point.

Q: Panophthalmitis involves ?

All structures of the eyeball including Tenon's capsule. ***All structures of the eyeball including Tenon's capsule*** - **Panophthalmitis** is a severe inflammation or infection that affects **all coats of the eyeball** (sclera, choroid, retina). - Crucially, it also extends to the **intraocular contents** and the **Tenon's capsule**, leading to potential destruction of the entire eye. *Inner coat of eyeball* - This description is characteristic of **uveitis** (inflammation of the uvea: iris, ciliary body, choroid) or **endophthalmitis** if it extends to the vitreous and retina. - However, **panophthalmitis** is a more extensive condition, involving more than just the inner coats. *Inner and outer coat but sparing tenon's capsule* - This scenario describes **endophthalmitis**, which involves inflammation of the internal structures of the eye (vitreous, retina, choroid) and potentially the sclera. - However, the sparing of Tenon's capsule differentiates it from **panophthalmitis**, which expressly includes involvement of this fibrous sheath. *None of the options* - This option is incorrect because Option C accurately describes the comprehensive nature of **panophthalmitis**, which is an inflammation of all ocular structures, including Tenon's capsule. - The definition of panophthalmitis is critical in distinguishing it from less severe inflammatory conditions of the eye.

Question 1

Which of the following statements about the c-wave in electroretinogram (ERG) is most accurate?

Accepted Answer

The 'c' wave is a slow positive wave.

Answer

The 'c' wave is a negative wave.

Answer

The 'b' wave arises primarily from photoreceptors.

Answer

The 'a' wave is a positive wave.

Question 2

Parachute lesions are associated with which of the following conditions?

Accepted Answer

Eale's disease

Answer

Diabetes

Answer

Sickle cell anemia

Answer

None of the options

Question 3

What condition is characterized by an "umbrella" configuration on fluorescein angiography?

Accepted Answer

Central serous retinopathy

Answer

Retinitis pigmentosa

Answer

Rhegmatogenous retinal detachment

Answer

Eale's disease

Question 4

Snow banking is seen in?

Accepted Answer

Intermediate uveitis

Answer

White coat syndrome

Answer

Eales syndrome

Answer

Diabetic kidney disease

Question 5

Which of the following is not a cause of exudative retinal detachment?

Accepted Answer

High myopia

Answer

Scleritis

Answer

Toxemia of pregnancy

Answer

Central serous retinopathy

Question 6

The most common cause of vitreous hemorrhage in adults is

Accepted Answer

Diabetes

Answer

Retinal hole

Answer

Trauma

Answer

Hypertension

Question 7

Birdshot retinopathy is characterized by all except?

Accepted Answer

Unilateral

Answer

Common in females

Answer

Creamy yellow spots

Answer

HLA-A29 positive

Question 8

The earliest change noticed in hypertensive retinopathy is:

Accepted Answer

Arteriolar spasm

Answer

Soft exudate

Answer

Venospasm

Answer

Hard exudate

Question 9

What is the thinnest portion of the sclera?

Accepted Answer

Posterior to the rectus muscle insertion

Answer

Anterior to the rectus muscle insertion

Answer

At the posterior pole

Answer

At the limbus

Question 10

Panophthalmitis involves ?

Accepted Answer

All structures of the eyeball including Tenon's capsule

Answer

Inner coat of eyeball

Answer

Inner and outer coat but sparing tenon's capsule

Answer

None of the options

NEET-PG 2013 — Ophthalmology