NEET-PG 2015 - Ophthalmology Practice Questions

Q: A 44-year-old woman presents with sudden painless loss of vision with a history of previous similar episodes. Fundoscopy shows no glow. What could be the possible diagnosis?

Vitreous Hemorrhage. ***Vitreous Hemorrhage*** - **Painless vision loss** is a hallmark symptom, and **previous similar episodes** suggest a recurrent condition, characteristic of vitreous hemorrhage from fragile vessels. - The **"no glow"** on fundoscopy indicates that light from the ophthalmoscope is unable to reflect off the retina due to something obstructing the clear media, such as blood in the vitreous cavity. *Rhegmatogenous Retinal Detachment* - While it causes **painless vision loss**, patients often report **floaters** or **flashes of light** preceding the detachment, which are not mentioned here. - Fundoscopy in rhegmatogenous retinal detachment would typically show a **grayish, elevated retina**, often with folds, not a complete loss of red reflex or ''no glow.'' *Acute Angle-Closure Glaucoma* - Characterized by **sudden, severe eye pain**, blurred vision, and often a **red eye** with a fixed, mid-dilated pupil. - Fundoscopy would typically reveal a **cupped optic disc** in advanced stages, but the primary finding is elevated intraocular pressure, with a clear vitreous, thus allowing an initial glow. *Fungal Keratitis* - This is an **infection of the cornea** that typically presents with pain, redness, photophobia, and a visible corneal ulcer or infiltrate. - Vision loss is gradual, and fundoscopy would still show a **normal red reflex** unless the corneal opacity is extremely dense, which is not implied by "no glow."

Q: What is the cause of glaucoma in retinoblastoma?

Neovascularisation. ***Neovascularisation*** - Retinoblastoma leads to **neovascularization of the iris (NVI)** and **angle structures** due to tumor necrosis, ischemia, and release of **angiogenic factors (VEGF)**. - The **neovascular membrane** grows over and obstructs the **trabecular meshwork** and anterior chamber angle, causing **secondary neovascular glaucoma**. - This is the **most characteristic and common mechanism** of glaucoma in advanced retinoblastoma. - Neovascular glaucoma in retinoblastoma is typically **refractory to medical treatment** and indicates poor prognosis. *Blockage of trabecular network* - While tumor cells can directly seed into the anterior chamber and block the trabecular meshwork, this mechanism is **less common** than neovascularization. - This option is also **less specific** as it doesn't identify the underlying pathophysiological process (neovascularization) that is characteristic of retinoblastoma-associated glaucoma. - Direct trabecular blockage by tumor cells typically occurs in advanced disease and often coexists with neovascularization. *Mass effect of the tumour* - The tumor mass itself rarely causes glaucoma through direct mechanical compression of outflow pathways. - Retinoblastoma causes glaucoma primarily through **secondary mechanisms** such as inflammation, neovascularization, or cellular seeding, not simple bulk effect. - Massive tumors may cause angle closure, but this is uncommon compared to neovascular mechanisms. *Lysis of the lens* - **Phacolytic glaucoma** from lens protein leakage is rare in retinoblastoma. - While lens damage can occur with advanced tumors, it is **not a typical or characteristic cause** of glaucoma in retinoblastoma. - The primary mechanisms involve the **tumor-angle-trabecular meshwork axis**, not lens pathology.

Q: What is the most common etiopathogenetic cause of glaucoma?

Decreased outflow. ***Decreased outflow*** - The most common cause of glaucoma is an **obstruction** or inefficiency in the drainage of **aqueous humor** from the eye, leading to its accumulation. - This reduced outflow results in an increase in **intraocular pressure (IOP)**, which damages the optic nerve. *Raised pressure in episcleral veins* - While elevated episcleral venous pressure can contribute to increased IOP and glaucoma, it is a **less common primary etiopathogenetic mechanism** compared to impaired outflow facility. - Conditions like **Sturge-Weber syndrome** or an **arteriovenous fistula** can cause this, but they are not the typical presentation of primary open-angle glaucoma. *Increased formation of aqueous humour* - An increase in the production of **aqueous humor** is rarely the primary cause of glaucoma. - The eye's regulatory mechanisms usually compensate, or if overproduction occurs, it is an **anatomical issue**, not an outflow issue. *Increased scleral outflow* - Increased **scleral outflow** (also known as uveoscleral outflow, which is a non-conventional drainage pathway) would actually lead to a **decrease** in intraocular pressure, not an increase. - This mechanism is often targeted by certain glaucoma medications (e.g., **prostaglandin analogues**) to lower IOP by facilitating drainage.

Q: Where is the intraocular lens placed during cataract surgery?

Capsular bag. ***Capsular bag*** - The **capsular bag** is the natural anatomical space where the human crystalline lens resides and is the ideal location for an intraocular lens (IOL) to mimic the natural lens's position and function. - Placing the IOL in the capsular bag provides **optimal stability**, centration, and reduces the risk of complications such as glare or secondary glaucoma. *Surface of iris* - Placing an IOL on the surface of the iris (**iris-fixated IOL**) is a less common surgical approach, typically reserved for cases where capsular support is absent or insufficient. - This position can lead to potential complications including **iris chafing**, pigment dispersion, and increased risk of uveitis or secondary glaucoma. *Over the face of vitreous* - Placing an IOL over the face of the vitreous typically occurs in cases of **capsular rupture** with inadequate posterior capsule support, requiring anterior vitrectomy and alternative IOL fixation. - This position is less stable and carries a higher risk of **vitreous prolapse**, retinal detachment, and cystoid macular edema compared to capsular bag placement. *Around the limbus* - The limbus is the **junction between the cornea and sclera** and is an entirely incorrect location for an intraocular lens implant. - An IOL around the limbus would be outside the globe and would serve no optical purpose within the eye, leading to **severe visual impairment** and potentially structural damage.

Q: Kayser-Fleischer ring is found in which layer of cornea?

Descemet's membrane. ***Descemet's membrane*** - Kayser-Fleischer rings are caused by **copper deposition** at the periphery of the cornea, specifically within **Descemet's membrane**. - This membrane is located between the **corneal stroma** and the **endothelium**. *Bowman's layer* - Bowman's layer is a thin, acellular layer of the cornea that lies beneath the **corneal epithelium**. - While it plays a role in corneal integrity, it is not the site of **copper deposition** in Wilson's disease. *Corneal stroma* - The corneal stroma is the thickest layer of the cornea, composed primarily of **collagen fibrils**. - Although it contains most of the corneal mass, **copper deposition** in Kayser-Fleischer rings does not specifically occur within the main stromal layer. *Endothelium* - The corneal endothelium is the innermost layer of the cornea, responsible for maintaining **corneal deturgescence**. - While it is adjacent to Descemet's membrane, the copper rings are deposited in the membrane itself, not directly in the endothelial cell layer.

Q: What is the type of cataract associated with Galactosemia?

Oil drop. ***Oil drop*** - This characteristic appearance is caused by the accumulation of **galactitol** in the lens, leading to changes in refractive index. - The "oil drop" cataract is a classic sign of **galactosemia**, often appearing as an early manifestation of the disease. *Snowflake cataract* - This type of cataract is more commonly associated with **diabetes mellitus** rather than galactosemia. - It presents as **fluffy white opacities** that can lead to rapid vision loss. *Blue dot cataract* - This is typically a **congenital stationary cataract** with small, bluish opacities in the peripheral lens. - It is usually **benign** and non-progressive, and not specifically linked to metabolic disorders like galactosemia. *Polychromatic lustre cataract* - This describes the varied, iridescent colors seen in certain types of cataracts, often associated with **complicated cataracts** or those near the lens sutures. - It does not specifically refer to the unique "oil drop" appearance of galactosemic cataracts.

Q: Most common age related change in vitreous?

Posterior vitreous detachment (PVD). ***Posterior vitreous detachment (PVD)*** - As we age, the **vitreous body** undergoes liquefaction and shrinkage, leading to its separation from the **retina**, most commonly posteriorly. - This is a very common and usually benign age-related phenomenon, often presenting with **floaters** and **flashes of light**. *Anterior vitreous detachment* - **Anterior vitreous detachment** is much less common than PVD and not typically considered the most frequent age-related change. - It often occurs secondary to **trauma** or specific surgical procedures rather than spontaneous aging alone. *Vitreous hemorrhage* - **Vitreous hemorrhage** is a pathological condition involving bleeding into the vitreous humor, often due to **diabetic retinopathy**, retinal tears, or trauma. - It is not a normal age-related change but a complication of underlying disease. *Vitritis* - **Vitritis** refers to inflammation of the vitreous humor, commonly associated with **uveitis** or infections. - It is an inflammatory disease process, not a physiological age-related degeneration of the vitreous.

Q: Which of the following conditions does not typically cause subconjunctival hemorrhages?

Pellagra. ***Pellagra*** - Pellagra is a **nutritional deficiency disease** caused by a lack of **niacin (vitamin B3)**, characterized by symptoms affecting the **skin, gastrointestinal tract, and nervous system** (dermatitis, diarrhea, dementia, and death if untreated) [1]. - It does **not typically cause subconjunctival hemorrhages** as it primarily affects other organ systems and isn't associated with vascular fragility in the conjunctiva like the other conditions listed [2]. *Whooping cough* - **Violent coughing paroxysms** in whooping cough (pertussis) can significantly increase **venous pressure in the head and neck**. - This elevated pressure can rupture small conjunctival blood vessels, leading to **subconjunctival hemorrhages**. *Scurvy* - Scurvy is caused by **vitamin C deficiency**, which is essential for collagen synthesis and maintaining **blood vessel integrity**. - Lack of vitamin C leads to **fragile capillaries**, making patients prone to bleeding, including **subconjunctival hemorrhages**. *Purpura* - Purpura refers to **purple-colored spots on the skin caused by bleeding underneath the skin**. It is a general term for various conditions characterized by **small vessel bleeding**. - These conditions often involve **vascular fragility or platelet abnormalities**, making individuals susceptible to bleeding in different sites, including the conjunctiva, resulting in **subconjunctival hemorrhages**.

Q: Which mode of ultrasonography is used to measure the axial length of the eyeball?

A-mode Ultrasonography. ***A-mode Ultrasonography*** - **A-mode** (amplitude modulation) ultrasonography is a **one-dimensional** display that measures the distance between structures based on the time it takes for sound waves to reflect. - It is specifically used for **biometry**, such as measuring the axial length of the eyeball for **intraocular lens (IOL) power calculation** prior to cataract surgery. *B-mode Ultrasonography* - **B-mode** (brightness modulation) ultrasonography provides a **two-dimensional** image, displaying the cross-sectional anatomy of organs. - While useful for visualizing ocular structures, it is not primarily used for precise **axial length measurements**. *M-mode Ultrasonography* - **M-mode** (motion mode) ultrasonography displays the **movement** of structures over time in a one-dimensional format. - This mode is typically used in **cardiac imaging** to assess heart valve motion and chamber dimensions, not for static length measurements of the eye. *None of the options* - This option is incorrect because **A-mode ultrasonography** is indeed the gold standard for measuring the axial length of the eyeball. - The other modes (B-mode and M-mode) serve different diagnostic purposes in ultrasonography.

Q: Sudden loss of vision without pain - Which of the following is NOT a cause?

Acute congestive glaucoma. ***Acute congestive glaucoma*** - This condition is characterized by **sudden, severe eye pain** along with blurred vision, redness, and a fixed, mid-dilated pupil. - The pain arises from abrupt elevation of **intraocular pressure**, which differentiates it from painless vision loss. *CRAO* - **Central Retinal Artery Occlusion** (CRAO) typically presents as **sudden, profound, painless monocular vision loss**. - Funduscopic examination often reveals a **cherry-red spot** in the fovea with generalized retinal whitening. *CSR* - **Central Serous Retinopathy** (CSR) causes **sudden, painless blurred vision** or a scotoma, often described as a "watery" or "shimmering" effect. - It involves leakage of fluid under the retina, typically in the macula. *Vitreous Hemorrhage* - Presents as **sudden, painless loss of vision** or a shower of floaters, often described as cobwebs or clouds. - It results from bleeding into the **vitreous cavity**, which can obscure the retina.

Question 1

A 44-year-old woman presents with sudden painless loss of vision with a history of previous similar episodes. Fundoscopy shows no glow. What could be the possible diagnosis?

Accepted Answer

Vitreous Hemorrhage

Answer

Rhegmatogenous Retinal Detachment

Answer

Acute Angle-Closure Glaucoma

Answer

Fungal Keratitis

Question 2

What is the cause of glaucoma in retinoblastoma?

Accepted Answer

Neovascularisation

Answer

Mass effect of the tumour

Answer

Blockage of trabecular network

Answer

Lysis of the lens

Question 3

What is the most common etiopathogenetic cause of glaucoma?

Accepted Answer

Decreased outflow

Answer

Raised pressure in episcleral veins

Answer

Increased formation of aqueous humour

Answer

Increased scleral outflow

Question 4

Where is the intraocular lens placed during cataract surgery?

Accepted Answer

Capsular bag

Answer

Surface of iris

Answer

Around the limbus

Answer

Over the face of vitreous

Question 5

Kayser-Fleischer ring is found in which layer of cornea?

Accepted Answer

Descemet's membrane

Answer

Endothelium

Answer

Bowman's layer

Answer

Corneal stroma

Question 6

What is the type of cataract associated with Galactosemia?

Accepted Answer

Oil drop

Answer

Snowflake cataract

Answer

Blue dot cataract

Answer

Polychromatic lustre cataract

Question 7

Most common age related change in vitreous?

Accepted Answer

Posterior vitreous detachment (PVD)

Answer

Anterior vitreous detachment

Answer

Vitreous hemorrhage

Answer

Vitritis

Question 8

Which of the following conditions does not typically cause subconjunctival hemorrhages?

Accepted Answer

Pellagra

Answer

Whooping cough

Answer

Scurvy

Answer

Purpura

Question 9

Which mode of ultrasonography is used to measure the axial length of the eyeball?

Accepted Answer

A-mode Ultrasonography

Answer

B-mode Ultrasonography

Answer

M-mode Ultrasonography

Answer

None of the options

Question 10

Sudden loss of vision without pain - Which of the following is NOT a cause?

Accepted Answer

Acute congestive glaucoma

Answer

CRAO

Answer

CSR

Answer

Vitreous Hemorrhage

NEET-PG 2015 — Ophthalmology