NEET-PG 2012 - Ophthalmology Practice Questions

Q: Shaffer's sign is seen in ?

Retinal detachment. ***Retinal detachment*** - **Shaffer's sign** refers to the presence of **pigment cells** (tobacco dust) in the **anterior vitreous**, indicating a retinal break or detachment. - This sign is due to the release of retinal pigment epithelium cells into the vitreous following a tear in the retina. *Acute angle-closure glaucoma* - This condition is characterized by a **sudden increase in intraocular pressure** due to blocked fluid outflow, causing pain, redness, and blurred vision. - It does not involve pigment cells in the vitreous, but rather changes in the **anterior chamber angle**. *Diabetic retinopathy* - This is a microvascular complication of diabetes, leading to damage to the blood vessels in the retina, causing **hemorrhages**, **exudates**, and **neovascularization**. - It does not typically present with free pigment in the vitreous as a primary diagnostic sign. *Age-related macular degeneration* - This condition affects the **macula**, often causing distorted vision and central vision loss, and is characterized by drusen and atrophy. - While it can involve retinal changes, it does not classically present with pigment cells in the vitreous as a diagnostic indicator.

Q: What is the most common cause of vitreous hemorrhage in diabetic retinopathy?

Proliferative diabetic retinopathy. ***Proliferative diabetic retinopathy*** - **Neovascularization** is the hallmark of proliferative diabetic retinopathy (PDR), where new, fragile blood vessels grow on the surface of the retina and optic disc. - These delicate vessels can easily rupture and bleed into the vitreous humor, leading to a **vitreous hemorrhage**. *Non-proliferative diabetic retinopathy* - This stage is characterized by **microaneurysms**, hemorrhages, and cotton wool spots, but typically lacks significant neovascularization. - While it involves retinal vascular damage, the absence of **newly formed, fragile vessels** makes vitreous hemorrhage less common. *Severe non-proliferative diabetic retinopathy* - This stage shows extensive microvascular abnormalities, including numerous hemorrhages and venular beading, but generally **still no new vessel formation**. - Without the presence of **fragile neovascular membranes**, the risk of significant vitreous hemorrhage is lower compared to PDR. *Diabetic macular edema* - This condition involves **fluid leakage** from damaged retinal vessels into the macula, causing vision loss. - While it's a common complication of diabetes, it primarily causes **macular swelling** and does not directly lead to vitreous hemorrhage.

Q: What is the definition of the visual axis in relation to the eye?

Line from the object to the fovea. ***Line from the object to the fovea*** - The **visual axis** is the theoretical line connecting the **object of regard** in the external world to the **fovea centralis** (the area of sharpest vision) on the retina. - This axis passes through the **nodal points** of the eye, which are conceptual points within the lens system acting as optical centers. *Line from the center of the lens to the cornea* - This description does not correspond to any standard anatomical or optical axis of the eye. - The **cornea** and **lens** are parts of the eye's refracting system, but a line solely between their centers would not define visual perception. *Line from the center of the cornea to the center of the lens* - This line is generally referred to as the **optical axis**, which is an anatomical reference line. - The optical axis typically passes through the centers of curvature of the refractive surfaces, but it does not necessarily align with the actual line of sight or the path of light from an object to the fovea. *None of the options* - This option is incorrect because the first option accurately defines the visual axis.

Q: What is the term for the fusion of the palpebral and bulbar conjunctiva?

Symblepharon. ***Symblepharon*** - **Symblepharon** is the term for the adhesion between the **palpebral conjunctiva** (lining the eyelid) and the **bulbar conjunctiva** (covering the eyeball). - This condition can limit eye movement and cause chronic irritation, often resulting from severe conjunctival inflammation or injury. *Trichiasis (inward growth of eyelashes)* - **Trichiasis** refers to the misdirection of eyelashes such that they rub against the cornea or conjunctiva. - It causes irritation, foreign body sensation, and can lead to corneal abrasion, but it does not involve fusion of conjunctival layers. *Ectropion (outward turning of eyelid)* - **Ectropion** is a condition where the lower eyelid turns outward or sags away from the eyeball. - This exposes the conjunctiva, causing dryness, irritation, and epiphora (excessive tearing), but it is not a fusion of conjunctival tissues. *Tylosis (thickening of skin on palms and soles)* - **Tylosis** is a medical term referring to diffuse **hyperkeratosis** or thickening of the skin, typically observed on the palms and soles. - This condition is completely unrelated to the conjunctiva or eye structures.

Q: Neonatal conjunctivitis is caused by all of the following except:

Aspergillus. ***Aspergillus*** - **Fungal infections** of the eye, particularly by *Aspergillus*, are extremely rare in neonates and typically present as **keratitis** rather than conjunctivitis. - While *Aspergillus* can cause severe infections in immunocompromised individuals, it is not a common cause of neonatal conjunctivitis. *Gonococcus* - **_Neisseria gonorrhoeae_** is a well-known cause of **ophthalmia neonatorum** (gonococcal conjunctivitis), presenting as severe, purulent discharge usually within the first 2-5 days of life. - This infection can lead to **corneal ulceration** and blindness if untreated. *Chlamydia* - **_Chlamydia trachomatis_** is the most common bacterial cause of **neonatal conjunctivitis**, typically appearing 5-14 days after birth. - It causes a **mucopurulent discharge** and can be associated with **chlamydial pneumonia** in infants. *Pseudomonas* - **_Pseudomonas aeruginosa_** can cause severe and rapidly progressive **neonatal conjunctivitis** and **keratitis**, especially in premature infants or those exposed to contaminated solutions. - It is a highly aggressive pathogen that can lead to significant ocular morbidity.

Q: Herpetic keratitis is treated by which of the following?

Acyclovir. ***Acyclovir*** - **Acyclovir** is an **antiviral agent** that specifically targets the **herpes simplex virus**, which is the causative agent of herpetic keratitis. - It works by inhibiting viral DNA replication, thereby reducing viral load and preventing further damage to the cornea. *Analgesics* - **Analgesics** are used to manage pain but do not address the **viral etiology** of herpetic keratitis. - While they can improve patient comfort, they are not a definitive treatment for the underlying infection. *Atropine* - **Atropine** is a **cycloplegic agent** used to paralyze the ciliary muscle and dilate the pupil, often to reduce pain from ciliary spasms in uveitis. - It does not have **antiviral properties** and is not effective against the herpes virus. *Steroids* - **Corticosteroids** can suppress inflammation but are generally **contraindicated** in active herpetic keratitis, especially in the epithelial form. - They can worsen the viral infection by compromising the immune response, potentially leading to **corneal ulceration** and perforation.

Q: Which virus is most commonly associated with disciform keratitis?

Herpes Simplex Virus (HSV). ***Herpes Simplex Virus (HSV)*** - **HSV** is the most common cause of **infectious disciform keratitis**, often following a primary ocular HSV infection or reactivation. - Disciform keratitis caused by HSV is a form of **immune-mediated stromal keratitis**, characterized by corneal edema, inflammation, and potential vision loss. *Rubella Virus* - While Rubella can cause ocular manifestations, such as **congenital cataracts** and **glaucoma** in infants, it is not typically associated with disciform keratitis in adults or children. - **Congenital rubella syndrome** is the primary context for ophthalmic issues related to this virus. *Human Immunodeficiency Virus (HIV)* - HIV can lead to various ocular complications, such as **CMV retinitis**, **Kaposi's sarcoma** of the conjunctiva, and **HIV retinopathy**. - However, HIV itself is **not directly linked** to disciform keratitis. *Hepatitis B Virus (HBV)* - HBV infection primarily affects the **liver** and is not commonly associated with direct ocular infections like keratitis. - Ocular manifestations are rare and often nonspecific, mainly related to systemic immune responses rather than direct viral replication in the eye.

Q: Metamorphopsia is seen in?

Posterior uveitis. ***Posterior uveitis*** - **Metamorphopsia**, or the perception of distorted images, can occur in **posterior uveitis** due to inflammation affecting the **retina** or **choroid**, leading to retinal edema or detachment. - Inflammatory processes in the posterior segment can cause disruption of photoreceptor alignment and function, altering the perception of straight lines and object shapes. *Anterior uveitis* - Primarily affects the **iris** and **ciliary body**, causing symptoms like **pain**, **photophobia**, **redness**, and reduced vision due to cellular exudates in the anterior chamber. - While vision can be affected, **metamorphopsia** is not a typical hallmark of anterior uveitis, as the retinal architecture is generally preserved. *Cataract* - Involves **clouding of the eye's natural lens**, leading to blurred vision, glare, and dullness of colors. - It does not cause **metamorphopsia** because the retinal structure and its perception of shapes remain intact; the distortion is primarily visual clarity, not shape. *Glaucoma* - Characterized by **progressive optic nerve damage** and visual field loss, often associated with elevated intraocular pressure. - While it causes vision impairment, typically starting with **peripheral vision loss**, it does not cause **metamorphopsia**, as the retina itself is usually not distorted.

Q: What is the most common type of congenital cataract?

Blue dot. ***Blue dot*** - **Blue dot (punctate) cataracts** are the **most common type of congenital cataract overall**. - They appear as **multiple small, blue-white opacities** scattered throughout the lens cortex. - These cataracts are typically **bilateral, non-progressive, and asymptomatic**, rarely affecting visual acuity. - Often considered **physiological variants**, they usually do not require surgical intervention. *Zonular (Lamellar)* - **Zonular (lamellar) cataracts** are the **most common visually significant** congenital cataract. - They feature **opacities arranged in layers or lamellae** within the lens, classically with alternating clear and opaque zones. - Unlike blue dot cataracts, these **often require surgical intervention** due to visual impairment. *Capsular* - **Capsular cataracts** involve the anterior or posterior lens capsule and are relatively uncommon. - They appear as **small, well-circumscribed opacities** on the lens capsule. - Visual impact depends on size and location relative to the visual axis. *Coralliform* - **Coralliform cataracts** are a rare type characterized by **coral-like branching opacities**. - This distinctive morphology makes them one of the less common congenital cataract types.

Q: The reduced effect of low astigmatism in dim light is primarily due to:

Pupil constriction. ***Pupil constriction*** - In dim light conditions, patients with low astigmatism may experience **reduced symptoms** due to the **pinhole effect** of pupil constriction when they squint or strain to see better. - **Pupil constriction** limits light entry to the central optical zone, reducing the effect of irregular corneal curvature by creating a smaller aperture that acts like a **stenopic slit**. - This **pinhole effect** improves depth of focus and reduces blur from astigmatism by eliminating peripheral aberrant rays. - When viewing in dim light, patients naturally squint to improve clarity, which mimics pupil constriction and reduces astigmatic blur. *Pupil dilatation* - **Pupil dilatation** in dim light would actually *increase* astigmatic symptoms, not reduce them. - A larger pupil allows more peripheral rays to enter the eye, which pass through areas of the lens and cornea with greater refractive error. - This increases the blur circle and worsens the optical quality in uncorrected astigmatism. *Increased curvature of lens* - **Increased lens curvature** (accommodation) increases refractive power but does not correct the unequal curvature of different meridians that defines astigmatism. - This would not specifically reduce astigmatic blur in dim light conditions. *Decreased curvature of lens* - **Decreased lens curvature** reduces refractive power and is associated with relaxed accommodation. - This does not address the fundamental issue of unequal meridional refraction in astigmatism.

Question 1

Shaffer's sign is seen in ?

Accepted Answer

Retinal detachment

Answer

Acute angle-closure glaucoma

Answer

Diabetic retinopathy

Answer

Age-related macular degeneration

Question 2

What is the most common cause of vitreous hemorrhage in diabetic retinopathy?

Accepted Answer

Proliferative diabetic retinopathy

Answer

Non-proliferative diabetic retinopathy

Answer

Severe non-proliferative diabetic retinopathy

Answer

Diabetic macular edema

Question 3

What is the definition of the visual axis in relation to the eye?

Accepted Answer

Line from the object to the fovea

Answer

Line from the center of the lens to the cornea

Answer

Line from the center of the cornea to the center of the lens

Answer

None of the options

Question 4

What is the term for the fusion of the palpebral and bulbar conjunctiva?

Accepted Answer

Symblepharon

Answer

Trichiasis (inward growth of eyelashes)

Answer

Ectropion (outward turning of eyelid)

Answer

Tylosis (thickening of skin on palms and soles)

Question 5

Neonatal conjunctivitis is caused by all of the following except:

Accepted Answer

Aspergillus

Answer

Chlamydia

Answer

Pseudomonas

Answer

Gonococcus

Question 6

Herpetic keratitis is treated by which of the following?

Accepted Answer

Acyclovir

Answer

Analgesics

Answer

Atropine

Answer

Steroids

Question 7

Which virus is most commonly associated with disciform keratitis?

Accepted Answer

Herpes Simplex Virus (HSV)

Answer

Rubella Virus

Answer

Human Immunodeficiency Virus (HIV)

Answer

Hepatitis B Virus (HBV)

Question 8

Metamorphopsia is seen in?

Accepted Answer

Posterior uveitis

Answer

Cataract

Answer

Glaucoma

Answer

Anterior uveitis

Question 9

What is the most common type of congenital cataract?

Accepted Answer

Blue dot

Answer

Capsular

Answer

Coralliform

Answer

Zonular

Question 10

The reduced effect of low astigmatism in dim light is primarily due to:

Accepted Answer

Pupil constriction

Answer

Pupil dilatation

Answer

Increased curvature of lens

Answer

Decreased curvature of lens

NEET-PG 2012 — Ophthalmology