NEET-PG 2015 - Ophthalmology Practice Questions

Q: Silk retina is seen in ?

Retinal detachment. ***Retinal detachment*** - **"Silk retina" or "silky sheen"** is a classic ophthalmoscopic finding in retinal detachment, describing the **smooth, glistening appearance** of the detached sensory retina. - The detached retina appears **elevated, gray, and translucent** with characteristic folds or undulations, exhibiting a **satiny or silky luster** when examined. - Patients typically present with **photopsias (flashes of light)**, **floaters**, and progressive **visual field defect** described as a "curtain" or "shadow." - This is a true **ophthalmic emergency** requiring urgent surgical intervention. *Diabetic retinopathy* - Characterized by **microaneurysms, dot-blot hemorrhages, hard exudates**, and **cotton-wool spots** in non-proliferative stages. - Proliferative diabetic retinopathy shows **neovascularization** and vitreous hemorrhage. - Does not produce the "silk retina" appearance. *Macular degeneration* - Age-related macular degeneration presents with **drusen, pigmentary changes**, and in advanced stages, **geographic atrophy** or **choroidal neovascularization**. - May show a **"beaten-bronze" appearance** in certain macular dystrophies (Best's disease), but not "silk retina." - Central vision loss is the predominant symptom. *Hypertensive retinopathy* - Features include **generalized arteriolar narrowing, AV nicking, flame-shaped hemorrhages**, and **cotton-wool spots**. - In severe cases (Grade IV), **optic disc edema** and macular star exudates may occur. - Vascular changes dominate the clinical picture, not a silky retinal appearance.

Q: Which of the following statements is false regarding Eale's disease?

Optic neuritis. ***Correct Answer: Optic neuritis*** - This statement is **false** because **Eale's disease** is a **peripheral retinal vasculitis** (periphlebitis) that primarily affects the **peripheral retinal veins**. - The condition does **NOT involve the optic nerve**, and **optic neuritis is NOT a recognized feature or complication** of Eale's disease. - The disease process is confined to the retinal vasculature and does not extend anteriorly to involve the optic disc or nerve in typical cases. *AKT is given* - While the exact etiology of Eale's disease remains uncertain, there is a **historical and clinical association with tuberculosis**, particularly in TB-endemic regions like India. - In clinical practice, **anti-tubercular therapy (ATT/AKT) is often empirically administered** when TB cannot be ruled out or when there is suspicion of systemic TB. - Some studies suggest ATT may help reduce inflammation and prevent recurrence in selected cases. *Vitreous Hemorrhage* - This is a **hallmark complication** of Eale's disease, particularly in stage 3 (proliferative stage). - **Recurrent vitreous hemorrhage** occurs due to rupture of fragile neovascular vessels that form in response to retinal ischemia. - It is one of the most common presentations requiring intervention. *Retinal detachment may occur* - **Tractional retinal detachment** is a recognized complication resulting from contraction of **fibrovascular proliferative membranes**. - **Rhegmatogenous retinal detachment** can also occur if vitreoretinal traction causes retinal breaks. - Both types may require surgical intervention (vitrectomy).

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: What is the primary function of glaucoma drainage devices?

Drain aqueous humour to an external device. **Drain aqueous humour to an external device** - Glaucoma drainage devices create an artificial outflow pathway, channeling excess **aqueous humour** from the anterior chamber to an external reservoir (usually under the conjunctiva) to lower intraocular pressure. - This bypasses the compromised natural drainage system, preventing further damage to the **optic nerve**. *Drain aqueous humour to the posterior segment* - Glaucoma drainage devices are designed to drain aqueous humour from the **anterior segment** (specifically the anterior chamber) of the eye, not the posterior segment. - The posterior segment primarily contains the **vitreous humour**, and drainage to this area is not the intended mechanism for IOP reduction. *Open the trabeculae mechanically* - Glaucoma drainage devices do not mechanically open the **trabecular meshwork**; this is the mechanism of action for procedures like goniotomy or trabeculoplasty. - These devices create an entirely new drainage pathway, bypassing the dysfunctional trabecular meshwork. *Reduce the aqueous secretion by compressing the ciliary epithelium* - Reducing aqueous humour secretion is the mechanism of action for medications like **beta-blockers** or **carbonic anhydrase inhibitors**, which act on the **ciliary epithelium**. - Glaucoma drainage devices focus on increasing outflow, not on reducing the production of aqueous humour.

Q: All of the following are true for retinopathy of prematurity except which of the following?

End result is bilateral blindness. ***End result is bilateral blindness*** - While retinopathy of prematurity (ROP) can lead to severe vision loss or blindness, it is not always a bilateral end result, especially with early diagnosis and treatment. The severity can vary between eyes, and some cases resolve spontaneously. - Modern screening and intervention strategies, such as laser photocoagulation or anti-VEGF injections, are often successful in preventing complete blindness in one or both eyes. *Due to hypoxia there occurs neovascularization followed by fibroproliferation* - This statement accurately describes the pathogenesis of ROP. The initial phase involves delayed normal retinal vascularization, followed by a proliferative phase characterized by **neovascularization** in response to hypoxia in the avascular retina. - These new, abnormal vessels are fragile and prone to bleeding, and their associated **fibrovascular proliferation** can lead to retinal detachment. *Blindness can be prevented by early diagnosis and ablation of vascular premature retina with cryotherapy or photocoagulation* - This is a true statement. **Early diagnosis** through ophthalmologic screening of premature infants is crucial, and treatments like **laser photocoagulation** or **cryotherapy** are effective in ablating the avascular peripheral retina to halt the progression of abnormal vessel growth. - These interventions reduce the hypoxic drive that fuels neovascularization, thereby preventing severe retinal detachment and subsequent blindness. *Occurs in premature infants due to abnormal retinal blood vessel development.* - This statement is correct. ROP is a disease primarily affecting **premature infants** because their retinal blood vessels have not completed development by the time of birth. - Postnatal factors, including oxygen fluctuations and low birth weight, further disrupt this critical development, leading to **abnormal vascularization**.

Q: 1mm change in axial length of the eyeball would change the refracting power of the eye by?

3D. ***3D*** - A 1mm change in the **axial length** of the eyeball leads to an approximate **3 diopter (D) change** in the refractive power of the eye. - This relationship is crucial for understanding **refractive errors** like myopia (if the eyeball is too long) or hyperopia (if it's too short). *1D* - A 1D change in refractive power corresponds to a much larger change in the **focal length** of the eye, not typically 1mm in axial length. - This value is too small to reflect the significant impact of a 1mm axial length alteration on the eye's focusing ability. *2D* - While a direct relationship exists, 2D is an **underestimation** of the actual refractive change caused by a 1mm alteration in axial length. - This value would imply a less sensitive optical system than the human eye. *4D* - A 4D change would represent an **overestimation** of the refractive power change for a 1mm alteration in axial length. - Such a high value is generally seen with more substantial anatomical variations or surgical interventions.

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: Pilocarpine is used in all of the following except:

Malignant Glaucoma. ***Malignant Glaucoma*** - **Pilocarpine** is contraindicated in **malignant glaucoma** because it can worsen the condition by causing **ciliary body edema** and anterior displacement of the lens-iris diaphragm. - This form of glaucoma requires treatment aimed at posterior displacement of the lens-iris diaphragm, often involving **cycloplegics**, **hyperosmotic agents**, or surgical interventions. *Primary, Open Angle Glaucoma* - **Pilocarpine** is an effective **miotic agent** that increases aqueous humor outflow through the **trabecular meshwork**, thereby lowering intraocular pressure. - It can be used as a treatment for **primary open-angle glaucoma**, although it is less commonly used due to its side effects and the availability of better-tolerated medications. *Acute Angle Closure Glaucoma* - **Pilocarpine** is typically used in the management of **acute angle-closure glaucoma** after the intraocular pressure has been acutely lowered by other agents. - It works by inducing **miosis**, which pulls the iris away from the **trabecular meshwork**, opening the angle and facilitating aqueous outflow. *Chronic Synechial Angle Closure Glaucoma* - In **chronic synechial angle-closure glaucoma**, **pilocarpine** can be used to break or prevent the formation of new **peripheral anterior synechiae** by constricting the pupil. - However, its effectiveness is limited if extensive synechiae have already formed, as these physically block the outflow pathway.

Question 1

Silk retina is seen in ?

Accepted Answer

Retinal detachment

Answer

Diabetic retinopathy

Answer

Macular degeneration

Answer

Hypertensive retinopathy

Question 2

Astigmatism is defined as?

Accepted Answer

Refractive error wherein refraction varies along different meridians

Answer

Refractive error due to long AP length of eyeball

Answer

Varying refractive error in both eyes

Answer

Varying shape perception by both eyes

Question 3

Which of the following statements is false regarding Eale's disease?

Accepted Answer

Optic neuritis

Answer

AKT is given

Answer

Vitreous Hemorrhage

Answer

Retinal detachment may occur

Question 4

What is regular astigmatism?

Accepted Answer

Astigmatism where the principal meridians are at a 90-degree angle to each other

Answer

Astigmatism in which the principal meridians are parallel

Answer

Asymptomatic astigmatism

Answer

Astigmatism as a result of cataract surgery

Question 5

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 6

What is the primary function of glaucoma drainage devices?

Accepted Answer

Drain aqueous humour to an external device

Answer

Drain aqueous humour to the posterior segment

Answer

Open the trabeculae mechanically

Answer

Reduce the aqueous secretion by compressing the ciliary epithelium

Question 7

All of the following are true for retinopathy of prematurity except which of the following?

Accepted Answer

End result is bilateral blindness

Answer

Due to hypoxia there occurs neovascularization followed by fibroproliferation

Answer

Occurs in premature infants due to abnormal retinal blood vessel development.

Answer

Blindness can be prevented by early diagnosis and ablation of avascular peripheral retina with cryotherapy or photocoagulation

Question 8

1mm change in axial length of the eyeball would change the refracting power of the eye by?

Accepted Answer

3D

Answer

1D

Answer

2D

Answer

4D

Question 9

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 10

Pilocarpine is used in all of the following except:

Accepted Answer

Malignant Glaucoma

Answer

Primary, Open Angle Glaucoma

Answer

Acute Angle Closure Glaucoma

Answer

Chronic Synechial Angle Closure Glaucoma

NEET-PG 2015 — Ophthalmology