NEET-PG 2012 - Ophthalmology Practice Questions

Q: Which muscle is the earliest to be involved in thyroid ophthalmopathy?

Inferior Rectus (IR). ***Inferior Rectus (IR)*** - The **inferior rectus muscle** is most commonly and earliest affected in **thyroid ophthalmopathy** due to its anatomical location and muscle fiber type, making it highly susceptible to inflammation and edema. - Involvement of the inferior rectus leads to restricted **upward gaze** and **diplopia**, which are characteristic early symptoms of thyroid eye disease. *Medial Rectus (MR)* - While the **medial rectus** is often involved in thyroid ophthalmopathy, it is typically affected *after* the inferior rectus. - Dysfunction of the medial rectus manifests as difficulty with **adduction** (moving the eye inwards). *Superior Rectus (SR)* - The **superior rectus** is less frequently and usually later involved compared to the inferior and medial rectus muscles. - Its involvement typically causes restricted **downward gaze**. *Lateral Rectus (LR)* - The **lateral rectus** muscle is the *least common* ocular muscle to be affected in thyroid ophthalmopathy. - When affected, it primarily causes difficulty with **abduction** (moving the eye outwards).

Q: What is the treatment of choice for amblyopia?

Occlusion therapy. ***Occlusion therapy*** - **Occlusion therapy** involves patching the stronger eye to force the weaker, amblyopic eye to work harder, thereby strengthening its neural connections. - This treatment is most effective when initiated during the **critical period of visual development** in childhood. *Corrective spectacles* - While essential for addressing **refractive errors** that may contribute to amblyopia, spectacles alone are often insufficient to resolve the amblyopia. - Spectacles primarily optimize the image quality on the retina, but don't directly address the **cortical suppression** of the amblyopic eye. *Surgical intervention* - **Surgical intervention** is typically reserved for correcting structural issues like **strabismus** (misalignment of the eyes) that contribute to amblyopia. - Surgery for strabismus aims to align the eyes, which can then be followed by occlusion therapy or other treatments to address the functional amblyopia. *Convergent exercises for vision therapy* - **Vision therapy exercises**, including convergent exercises, may be used as an adjunct to occlusion therapy or in cases of **convergence insufficiency**. - However, they are not the primary or solitary treatment of choice for amblyopia, which requires direct stimulation of the amblyopic eye.

Q: Most common orbital tumor has its origin from?

Blood vessels. ***Blood vessels*** - The most common orbital tumor in childhood is a **capillary hemangioma**, which originates from blood vessels. - In adults, the most common primary orbital tumor is an orbital varix, also a **vascular lesion**. *Nerves* - Tumors of neural origin, such as **optic nerve gliomas** or **meningiomas**, are less common than vascular tumors. - While significant, they do not represent the *most* common overall origin for orbital tumors. *Muscle* - Tumors originating from muscle, such as **rhabdomyosarcoma** in children (a malignant tumor), are relatively rare. - **Pseudotumor** (idiopathic orbital inflammation), though common, is an inflammatory condition, not a true neoplasm of muscle origin. *Lymph node* - Tumors of lymphoid origin, such as **lymphomas**, are malignant and can occur in the orbit. - However, they are not the most common primary orbital tumor compared to those of vascular origin.

Q: What is the most common cause of intermittent proptosis in adults?

Orbital varix. ***Orbital varix*** - An **orbital varix** is essentially a varicose vein within the orbit, which can cause intermittent proptosis. - Proptosis in an orbital varix is often exacerbated by activities that increase venous pressure, such as **Valsalva maneuvers**, crying, or bending over. *Thyroid ophthalmopathy* - This condition is characterized by **persistent proptosis**, lid retraction, and ophthalmoplegia, rather than intermittent symptoms. - While it can cause proptosis, it typically presents as **constant and progressive** rather than intermittent proptosis that varies with head position or straining. *Neuroblastoma* - This is a **malignant tumor** that primarily affects infants and young children, not typically adults. - Orbital metastasis from neuroblastoma would cause **progressive, constant proptosis** rather than intermittent proptosis. *Retinoblastoma* - **Retinoblastoma** is a malignant tumor of the retina that primarily affects young children, typically under the age of 5. - While it can cause proptosis in advanced stages, it presents as **constant and progressive proptosis** due to tumor growth, not intermittent proptosis.

Q: What is the first sign of iridocyclitis?

Aqueous flare. ***Aqueous flare*** - This is the earliest and most subtle sign, representing an increase in **protein content** in the aqueous humor due to breakdown of the **blood-aqueous barrier**. - It is detected by a **slit-lamp examination** as a hazy appearance in the anterior chamber, similar to a car headlight beam in fog. *KP* - **Keratic precipitates (KP)** are deposits of inflammatory cells on the corneal endothelium. - While characteristic of iridocyclitis, they typically appear **after** the initial breakdown of the blood-aqueous barrier that causes aqueous flare. *Congestion* - **Ciliary congestion** (perilimbal redness) is a common symptom of anterior uveitis, but it is a visible sign of inflammation. - The underlying inflammatory process causing the congestion first manifests as **subtle changes in the aqueous humor**, which is aqueous flare. *Trichiasis* - **Trichiasis** is the misdirection of eyelashes to rub against the cornea, causing irritation. - It is an **external ocular condition** and is not a sign of intraocular inflammation like iridocyclitis.

Q: In the context of homocystinuria, which direction does the lens typically subluxate?

Inferonasal. ***Inferonasal*** - In **homocystinuria**, the **ectopia lentis** (lens subluxation) often occurs due to weakening of the **zonular fibers**. - The classic direction for lens subluxation in homocystinuria is **inferior and nasal**. *Inferotemporal* - While lens subluxation can occur in various directions, **inferotemporal** is not the classic or most common presentation in homocystinuria. - This direction is less specific and does not strongly point to homocystinuria as the underlying cause. *Superonasal* - **Superonasal** dislocation of the lens is more characteristic of **Marfan syndrome**, which is important to differentiate from homocystinuria. - This direction helps distinguish different causes of lens ectopia. *Superotemporal* - **Superotemporal** lens subluxation is the hallmark of **Marfan syndrome**, a genetic connective tissue disorder. - This specific finding is crucial for differential diagnosis in patients presenting with lens ectopia.

Q: Which type of cataract is associated with the phenomenon known as 'second sight'?

Nuclear cataract. ***Nuclear cataract*** - A nuclear cataract causes the lens to become more **myopic** or nearsighted due to an increase in its **refractive index**. - This temporary increase in nearsightedness can allow elderly individuals who previously needed reading glasses (due to presbyopia) to read without them, a phenomenon known as "**second sight**." *Cortical cataract* - Cortical cataracts primarily affect the **outer layer or cortex** of the lens, appearing as spokes or wedges radiating from the periphery. - They tend to cause **glare** and **reduced peripheral vision**, but generally do not improve near vision. *Zonular cataract* - A zonular cataract is a **congenital type of cataract**, characterized by opacity in specific layers (lamellae) of the lens, often in the fetal nucleus. - It does not typically lead to the "second sight" phenomenon, as it is present from birth and affects vision differently. *Punctate cataract* - Punctate cataracts are small, **dot-like opacities** scattered throughout the lens, often considered benign. - They are usually **incidental findings** and rarely cause significant visual disturbances or "second sight."

Q: Which of the following statements is false about phacolytic glaucoma?

Primarily caused by iris-lens contact. ***Primarily caused by iris-lens contact*** - This statement is **FALSE** because **phacolytic glaucoma** is caused by the leakage of **lens proteins** from a **hypermature cataract** into the **anterior chamber**, not by iris-lens contact. - **Iris-lens contact** is the mechanism in **pupillary block glaucoma** and **acute angle-closure glaucoma**, not in phacolytic glaucoma. - The pathophysiology involves **macrophages** engulfing leaked lens proteins and obstructing the **trabecular meshwork**. *Open angle glaucoma* - This statement is true because **phacolytic glaucoma** is definitively an **open-angle glaucoma**. - It involves obstruction of the **trabecular meshwork** by **macrophages** laden with **lens proteins**, which is an open-angle mechanism. - The angle remains anatomically open but functionally blocked. *Seen in hypermature stage of cataract* - This statement is true because **phacolytic glaucoma** develops when the **lens capsule** of a **hypermature (Morgagnian) cataract** becomes permeable. - This permeability allows **high-molecular-weight lens proteins** to leak into the **aqueous humor**. *Lens induced glaucoma* - This statement is true as **phacolytic glaucoma** is a specific type of **lens-induced glaucoma**, arising from the toxic effects of **leaked lens material**. - Other forms of **lens-induced glaucoma** include **phacomorphic glaucoma**, **lens-particle glaucoma**, and **phacoanaphylactic glaucoma**.

Q: Broadest neuroretinal rim is seen in -

Inferior pole. ***Inferior pole*** - The **inferior pole** of the optic disc typically has the broadest neuroretinal rim in healthy eyes. - This observation is often remembered by the "ISNT rule," where **I > S > N > T** (Inferior > Superior > Nasal > Temporal) describes the typical thickness of the neuroretinal rim. *Superior pole* - While the superior pole has a relatively thick neuroretinal rim, it is generally **thinner than the inferior rim**. - The superior rim is the second thickest based on the **ISNT rule**. *Nasal pole* - The nasal pole's neuroretinal rim is typically **thinner than both the inferior and superior poles**. - It ranks third in thickness according to the **ISNT rule**. *Temporal pole* - The temporal pole typically has the **thinnest neuroretinal rim**, making it the narrowest part of the disc. - This is due to the larger excavation of the optic cup temporally, accommodating the macular fibers.

Q: What condition is characterized by a salt and pepper fundus appearance in the retina?

Congenital syphilis. ***Congenital syphilis*** - The **"salt and pepper" fundus** appearance is a classic ophthalmologic finding in congenital syphilis, resulting from diffuse pigmentary retinopathy. - This condition is caused by widespread pigmentary changes in the retina, affecting both the retinal pigment epithelium and neurosensory retina. - It represents chronic, bilateral, and symmetric chorioretinitis that is pathognomonic for congenital syphilis. *Congenital toxoplasmosis* - While it can cause chorioretinitis, congenital toxoplasmosis typically presents with **focal, destructive lesions** rather than diffuse "salt and pepper" pigmentary changes. - Classic ocular lesions are often described as a **"headlight in the fog"** or inactive, pigmented chorioretinal scars. *Congenital histoplasmosis* - Ocular histoplasmosis syndrome (OHS) is usually acquired, not congenital, and causes **discrete chorioretinal scars** ("histo spots") often in the macula or peripapillary region. - It does not result in a diffuse **"salt and pepper" fundus** appearance. *Congenital rubella* - Congenital rubella syndrome can cause pigmentary retinopathy, but the pattern is typically **patchy or mottled** rather than the classic "salt and pepper" appearance. - Other ocular findings include cataract, microphthalmos, and glaucoma.

Question 1

Which muscle is the earliest to be involved in thyroid ophthalmopathy?

Accepted Answer

Inferior Rectus (IR)

Answer

Medial Rectus (MR)

Answer

Superior Rectus (SR)

Answer

Lateral Rectus (LR)

Question 2

What is the treatment of choice for amblyopia?

Accepted Answer

Occlusion therapy

Answer

Corrective spectacles

Answer

Surgical intervention

Answer

Convergent exercises for vision therapy

Question 3

Most common orbital tumor has its origin from?

Accepted Answer

Blood vessels

Answer

Nerves

Answer

Muscle

Answer

Lymph node

Question 4

What is the most common cause of intermittent proptosis in adults?

Accepted Answer

Orbital varix

Answer

Thyroid ophthalmopathy

Answer

Neuroblastoma

Answer

Retinoblastoma

Question 5

What is the first sign of iridocyclitis?

Accepted Answer

Aqueous flare

Answer

KP

Answer

Congestion

Answer

Trichiasis

Question 6

In the context of homocystinuria, which direction does the lens typically subluxate?

Accepted Answer

Inferonasal

Answer

Inferotemporal

Answer

Superonasal

Answer

Superotemporal

Question 7

Which type of cataract is associated with the phenomenon known as 'second sight'?

Accepted Answer

Nuclear cataract

Answer

Cortical cataract

Answer

Zonular cataract

Answer

Punctate cataract

Question 8

Which of the following statements is false about phacolytic glaucoma?

Accepted Answer

Primarily caused by iris-lens contact

Answer

Open angle glaucoma

Answer

Lens induced glaucoma

Answer

Seen in hypermature stage of cataract

Question 9

Broadest neuroretinal rim is seen in -

Accepted Answer

Inferior pole

Answer

Nasal pole

Answer

Superior pole

Answer

Temporal pole

Question 10

What condition is characterized by a salt and pepper fundus appearance in the retina?

Accepted Answer

Congenital syphilis

Answer

Congenital rubella

Answer

Congenital toxoplasmosis

Answer

Congenital histoplasmosis

NEET-PG 2012 — Ophthalmology