NEET-PG 2015 Practice Questions

Q: Anisocoria in Horner's syndrome is due to

Disruption of the oculosympathetic pathway. ***Disruption of the oculosympathetic pathway*** - Horner's syndrome results from a lesion interrupting the **oculosympathetic pathway**, leading to classic symptoms of **miosis**, **ptosis**, and **anhidrosis** [1]. - The **miosis** (constricted pupil) specifically arises from the unopposed action of the **parasympathetic innervation** to the pupil dilatory muscles when sympathetic innervation is disrupted. *Disruption of the oculoparasympathetic pathway* - Disruption of the oculoparasympathetic pathway would result in **mydriasis** (dilated pupil), not miosis as seen in Horner's syndrome [2]. - This pathway is responsible for stimulating the **pupillary constrictor muscles**, and its disruption would lead to an inability to constrict the pupil [3]. *Disruption of the oculomotor nerve* - The **oculomotor nerve** (CN III) carries parasympathetic fibers to the eye, and its disruption typically causes a **fixed and dilated pupil** due to unopposed sympathetic action [3]. - Oculomotor nerve palsy also presents with **ptosis** and **down-and-out deviation** of the eye, which are not characteristic of isolated Horner's syndrome [1], [4]. *Disruption of the abducens nerve* - The **abducens nerve** (CN VI) solely innervates the **lateral rectus muscle**, responsible for abducting the eye. - Disruption of the abducens nerve causes **diplopia** and an inability to abduct the affected eye, with no direct impact on pupil size.

Q: Macular sparing is associated with lesions in:

Lesions in the occipital cortex. ***Lesions in the occipital cortex*** - **Macular sparing** occurs when the central visual field (macula) is preserved despite damage to the occipital cortex, often due to its dual blood supply from the **middle cerebral artery** and the **posterior cerebral artery**. [2] - This phenomenon typically results from a **vascular lesion** in the occipital lobe, leading to a **homonymous hemianopia** with a distinct sparing of the foveal region. [2], [3] *Lesions in the optic nerve* - Lesions in the optic nerve cause **monocular vision loss** or central scotomas, rather than the homonymous visual field defects associated with macular sparing. [2] - Damage here affects the visual pathway **before** the optic chiasm, impacting the entire visual input from one eye. [2] *Lesions in the lateral geniculate body* - Lesions in the **lateral geniculate body (LGB)** produce **contralateral homonymous hemianopia** or quadrantanopia, but typically **do not exhibit macular sparing** as consistently as cortical lesions. - The LGB processes visual information from both eyes before relaying it to the visual cortex. [1] *Lesions in the optic chiasma* - Lesions in the **optic chiasma** classically cause **bitemporal hemianopia**, affecting the temporal visual fields of both eyes. [2] - This type of visual field defect is distinct from the homonymous defects seen with macular sparing, as it results from damage to the **crossing nasal fibers**. [2]

Q: Purtscher's retinopathy is associated with -

Head trauma. ***Head trauma*** - **Purtscher's retinopathy** is a rare occlusive microvasculopathy characterized by sudden vision loss and specific retinal findings, classically associated with **head or chest trauma**. - The condition occurs due to **fat embolization** and **leukoembolization** with complement activation, leading to occlusion of retinal precapillary arterioles. - Classic findings include **cotton wool spots**, intraretinal hemorrhages, and **Purtscher flecken** (polygonal areas of retinal whitening between the optic disc and macula). - The term "Purtscher's retinopathy" specifically refers to trauma-induced cases, while "Purtscher-like retinopathy" describes similar findings from non-traumatic causes (acute pancreatitis, fat embolism syndrome, amniotic fluid embolism). *Diabetes Mellitus* - **Diabetic retinopathy** is associated with chronic hyperglycemia causing microvascular damage, characterized by microaneurysms, dot-blot hemorrhages, hard exudates, and venous beading. - It involves gradual progressive changes over years, not acute embolic occlusion from trauma. - Advanced stages include **proliferative diabetic retinopathy** with neovascularization and diabetic macular edema. *Wilson's disease* - **Wilson's disease** is an autosomal recessive disorder of copper metabolism affecting the liver, brain, and eyes. - Ocular manifestations include **Kayser-Fleischer rings** (copper deposition in Descemet's membrane) and sunflower cataracts. - It does not cause acute retinal vascular occlusion or the specific findings of Purtscher's retinopathy. *Rheumatoid arthritis* - **Rheumatoid arthritis** is a chronic autoimmune inflammatory disease primarily affecting joints. - Ocular manifestations include **keratoconjunctivitis sicca** (dry eyes), **episcleritis**, **scleritis**, and peripheral ulcerative keratitis. - It is not associated with Purtscher's retinopathy, which is specifically linked to traumatic or embolic events.

Q: What is the typical appearance of a subhyaloid hemorrhage in the eye?

Boat shaped. ***Boat shaped*** - A subhyaloid hemorrhage is located beneath the **hyaloid membrane** (the posterior vitreous cortex), which is attached to the retina. - The collected blood often assumes a **dependent, gravity-influenced shape**, appearing flat on top and curved underneath, resembling a boat. *Crescent shaped* - This shape is not characteristic of a typical subhyaloid hemorrhage; it might be seen in other types of hemorrhages or detachment patterns. - **Crescentic shapes** are more commonly associated with certain types of **retinal detachments** or tears where fluid accumulation takes on a curved boundary. *Round* - While hemorrhages can be round, a subhyaloid hemorrhage typically spreads out due to gravity within the confined space, resulting in a more distinct shape. - A **perfectly round hemorrhage** is less common in the subhyaloid space as blood tends to layer out rather than remain as a sphere. *Flame shaped* - **Flame-shaped hemorrhages** are typically found in the **nerve fiber layer** due to the orientation of nerve fibers. - These hemorrhages are shallower and follow the linear arrangement of nerve fibers, unlike the larger, more globular subhyaloid bleeds.

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: Muscae volitantes is seen in?

Vitreous detachment. ***Vitreous detachment*** - **Muscae volitantes** (Latin for "flying flies") is the classical term for **vitreous floaters** - **Posterior vitreous detachment (PVD)** is the **most common cause** of muscae volitantes - PVD occurs due to **vitreous liquefaction** and **vitreoretinal separation**, causing **collagen fibers and cellular debris** to cast shadows on the retina - These floaters are typically described as **spots, cobwebs, or threads** that move with eye movement - PVD is extremely common, particularly **after age 50-60 years**, and in **myopic patients** *Remains of primitive hyaloid vasculature* - **Hyaloid remnants** (such as **Mittendorf's dot** or **Bergmeister's papilla**) are **congenital developmental anomalies** - While these can occasionally be visible as small opacities, they are **not the classical cause** of muscae volitantes - These are typically **stationary** rather than "floating" as the term implies *Vitreous Hemorrhage* - Causes **sudden onset** of numerous floaters, often described as **"shower of red blood cells"** or dense black spots - Associated with **significant vision loss** and requires urgent evaluation - Not the benign, chronic floaters typical of muscae volitantes *Eale's disease* - **Peripheral retinal vasculitis** causing **recurrent vitreous hemorrhages** - Floaters occur secondary to **hemorrhage**, not the primary pathology of muscae volitantes - Presents with **recurrent episodes** and **vision loss**, not isolated benign floaters

Q: Which of the following statements is MOST likely false regarding optic neuritis?

Abnormal electroretinogram. ***Abnormal electroretinogram*** - Optic neuritis primarily affects the **optic nerve**, which is responsible for transmitting visual information from the retina to the brain. - The **electroretinogram (ERG)** measures the electrical activity of the **retina** in response to light, which is usually normal in optic neuritis as the retina itself is not the primary site of pathology. *Decreased pupillary reflex* - Optic neuritis often causes a **relative afferent pupillary defect (RAPD)**, where the affected eye's pupil dilates instead of constricting when light is swung from the unaffected to the affected eye. - This indicates a decrease in the afferent nerve signal transmission due to damage to the optic nerve. *Decreased visual acuity* - A hallmark symptom of optic neuritis is **acute vision loss**, which can range from mild blurring to severe vision impairment. - This vision loss is typically unilateral and can progress over several days. *Abnormal visual evoked potentials (VEP)* - **VEPs** measure the electrical activity of the brain in response to visual stimuli, assessing the integrity of the optic nerve and visual pathways. - In optic neuritis, the demyelination and damage to the optic nerve cause a **slowing of nerve conduction**, leading to increased latency and reduced amplitude in VEPs.

Q: The most common type of strabismus seen in myopes is?

Intermittent Exotropia. ***Intermittent Exotropia*** - Myopes often employ less **accommodative effort** for near tasks, leading to reduced **accommodative convergence** and an increased tendency for the eyes to drift outwards. - This outward deviation, or **exotropia**, is frequently intermittent, especially during fatigue or inattention. *Intermittent Esotropia* - **Esotropia** is an inward turn of the eye and is typically associated with **hyperopia** due to excessive accommodative effort leading to increased accommodative convergence. - While it can be intermittent, it is not the most common form of strabismus in myopic individuals. *Esotropia hypotropia complex* - This complex involves both an inward deviation (**esotropia**) and a downward deviation (**hypotropia**). - It is not typically seen in healthy myopes and would suggest other underlying **neurological** or **structural abnormalities**. *Exotropia Hypotropia complex* - While **exotropia** can be common in myopes, the additional presence of **hypotropia** (downward deviation) suggests a more complex strabismic picture. - This combination is not the most frequent strabismus seen in uncomplicated myopia and may indicate **cranial nerve palsies** or **orbital anomalies**.

Q: Dalrymple's sign of ocular Graves' disease refers to which of the following?

Retraction of the upper lid. ***Retraction of the upper lid*** - **Dalrymple's sign** specifically refers to the **wide-eyed stare** seen in **Graves' ophthalmopathy** due to **retraction of the upper eyelid**. - This symptom is caused by sympathetic overactivity of the **levator palpebrae superioris muscle**. *Lid lag* - **Lid lag (Graefe's sign)** is a different ocular sign where the **upper eyelid lags behind the globe** on downward gaze. - While also seen in **Graves' disease**, it is distinct from constant upper lid retraction. *Proptosis* - **Proptosis**, or **exophthalmos**, is the **forward protrusion of the eyeball** from the orbit. - This is a common feature of **Graves' ophthalmopathy**, but it is not what Dalrymple's sign refers to. *Convergence insufficiency* - **Convergence insufficiency (Moebius sign)** refers to the **inability to maintain convergence** during near vision. - While this can occur in **thyroid eye disease**, it is not Dalrymple's sign.

Q: D Shaped pupil is seen in which condition?

Iridodialysis. ***Iridodialysis*** - **Iridodialysis** is a disinsertion or separation of the iris from its root at the ciliary body. - This separation creates a D-shaped or keyhole pupil, as the detached portion of the iris no longer contributes to the circular pupillary margin. *Anterior Uveitis* - **Anterior uveitis** is inflammation of the iris and ciliary body, primarily causing miosis (constricted pupil), not a D-shaped pupil. - It can lead to posterior synechiae, resulting in an irregular, but not typically D-shaped, pupil. *Anterior synechiae* - **Anterior synechiae** involve adhesions between the iris and the corneal endothelium or trabecular meshwork. - While they can cause an irregular pupil shape, they typically pull the iris towards the cornea rather than creating a D-shape from iris root disinsertion. *Iridodonesis* - **Iridodonesis** refers to tremors or wobbling of the iris, often seen in cases of aphakia or subluxated lenses, due to lack of support. - It describes a movement disorder of the iris rather than an abnormal, fixed pupil shape like a D-shaped pupil.

Question 1

Anisocoria in Horner's syndrome is due to

Accepted Answer

Disruption of the oculosympathetic pathway

Answer

Disruption of the oculoparasympathetic pathway

Answer

Disruption of the oculomotor nerve

Answer

Disruption of the abducens nerve

Question 2

Macular sparing is associated with lesions in:

Accepted Answer

Lesions in the occipital cortex

Answer

Lesions in the optic nerve

Answer

Lesions in the lateral geniculate body

Answer

Lesions in the optic chiasma

Question 3

Purtscher's retinopathy is associated with -

Accepted Answer

Head trauma

Answer

Diabetes Mellitus

Answer

Wilson's disease

Answer

Rheumatoid arthritis

Question 4

What is the typical appearance of a subhyaloid hemorrhage in the eye?

Accepted Answer

Boat shaped

Answer

Crescent shaped

Answer

Round

Answer

Flame shaped

Question 5

Most common age related change in vitreous?

Accepted Answer

Posterior vitreous detachment (PVD)

Answer

Anterior vitreous detachment

Answer

Vitreous hemorrhage

Answer

Vitritis

Question 6

Muscae volitantes is seen in?

Accepted Answer

Vitreous detachment

Answer

Vitreous Hemorrhage

Answer

Remains of primitive hyaloid vasculature

Answer

Eale's disease

Question 7

Which of the following statements is MOST likely false regarding optic neuritis?

Accepted Answer

Abnormal electroretinogram

Answer

Decreased pupillary reflex

Answer

Decreased visual acuity

Answer

Abnormal visual evoked potentials (VEP)

Question 8

The most common type of strabismus seen in myopes is?

Accepted Answer

Intermittent Exotropia

Answer

Intermittent Esotropia

Answer

Esotropia Hypotropia complex

Answer

Exotropia Hypotropia complex

Question 9

Dalrymple's sign of ocular Graves' disease refers to which of the following?

Accepted Answer

Retraction of the upper lid

Answer

Lid lag

Answer

Proptosis

Answer

Convergence insufficiency

Question 10

D Shaped pupil is seen in which condition?

Accepted Answer

Iridodialysis

Answer

Anterior synechiae

Answer

Anterior Uveitis

Answer

Iridodonesis

NEET-PG 2015

Internal Medicine

Ophthalmology