NEET-PG 2013 - Ophthalmology Practice Questions

Q: Retinitis pigmentosa is characterized by ?

Loss of peripheral vision. ***Loss of peripheral vision*** - Retinitis pigmentosa is a group of genetic disorders that cause **progressive degeneration of photoreceptor cells**, primarily rods, which are concentrated in the periphery of the retina. - This degeneration leads to a gradual **loss of peripheral vision**, often beginning with **night blindness** and progressing to tunnel vision. *Loss of central vision* - Loss of central vision is characteristic of conditions affecting the **macula**, such as **age-related macular degeneration** or certain forms of **macular dystrophy**. - While later stages of retinitis pigmentosa can affect central vision, the initial and primary characteristic is loss of peripheral vision. *Tubular vision* - **Tubular vision** is an advanced stage of peripheral vision loss, where the visual field shrinks to a narrow central area, resembling looking through a tube. - While it can be a consequence of retinitis pigmentosa, it is a description of the **extent of visual field constriction** rather than the primary characteristic of the disease itself. *Visual field constriction* - **Visual field constriction** is a general term for any reduction in the extent of the visual field. - While retinitis pigmentosa certainly causes visual field constriction, the term "loss of peripheral vision" is more specific to the initial and dominant pattern of vision loss in this condition.

Q: Which of the following statements about the c-wave in electroretinogram (ERG) is most accurate?

The 'c' wave is a slow positive wave.. ***The 'c' wave is a slow positive wave.*** - The **c-wave** in an ERG is generated by the **retinal pigment epithelium (RPE)** and is characterized by its **slow, positive deflection**. - It reflects the **hyperpolarization** of the RPE cells in response to light stimulation. *The 'c' wave is a negative wave.* - This statement is incorrect because the **c-wave** is consistently observed as a **positive deflection** in the ERG tracing. - A negative wave like the **a-wave** is generated by photoreceptor hyperpolarization, which is a different component. *The 'b' wave arises primarily from photoreceptors.* - The **b-wave** primarily arises from the **Müller cells** and **bipolar cells**, not directly from photoreceptors. - Photoreceptor activity is primarily reflected in the **a-wave**. *The 'a' wave is a positive wave.* - The **a-wave** is a **negative deflection** in the ERG, representing the **hyperpolarization of photoreceptors** in response to light. - It is the earliest component of the ERG waveform.

Q: Arcuate field defect akin to glaucoma is seen in?

Optic nerve lesion. ***Optic nerve lesion*** - An **arcuate field defect** is a specific pattern of visual field loss that follows the course of nerve fibers in the retina and is characteristic of **optic nerve damage**, similar to what is seen in glaucoma. - This type of defect is due to damage to the **bundle of retinal nerve fibers** that arch above or below the macula, often causing a scotoma (blind spot) that respects the horizontal meridian. - Common causes include **anterior ischemic optic neuropathy (AION)**, **optic neuritis**, and other optic nerve pathologies that affect the nerve fiber layer. *Pituitary adenoma* - A pituitary adenoma typically causes a **bitemporal hemianopsia** due to compression of the optic chiasm. - This visual field defect involves the lateral halves of both visual fields, which is different from an arcuate defect. *Posterior cerebral artery infarct* - An infarct in the posterior cerebral artery typically leads to a **homonymous hemianopsia** (loss of half of the visual field on the same side in both eyes) or a quadrantanopsia. - This type of defect results from damage to the **visual cortex** or optic radiations, not the optic nerve itself in a glaucoma-like pattern. *None of the options* - This is incorrect because **optic nerve lesion** is a valid and correct answer. - Optic nerve pathologies are well-established causes of arcuate field defects similar to those seen in glaucoma.

Q: Binocular single vision is tested by?

Synoptophore. ***Synoptophore*** - The **synoptophore** is an ophthalmic instrument used to diagnose and treat various binocular vision anomalies, including **strabismus** and suppression. - It allows for the precise measurement and assessment of the eyes' ability to **fuse images** from both eyes into a single perception, which is the essence of **binocular single vision**. *Amsler grid* - The **Amsler grid** is primarily used to detect central visual field defects, such as those caused by **macular degeneration** or other retinal pathologies. - It does not directly assess the brain's ability to fuse images from both eyes into a single vision. *Cardboard test* - The "cardboard test" is not a standard ophthalmic test for binocular single vision. - It may refer to various informal or rudimentary tests, but it lacks the precision and standardization required for accurate assessment of binocular functions. *Maddox rod* - The **Maddox rod** is used to detect and measure **heterophoria** (latent strabismus) or **heterotropia** (manifest strabismus). - It dissociates the images seen by each eye, preventing fusion and revealing the deviation of the eyes, rather than directly testing the ability to achieve binocular single vision.

Q: Stocker's line is seen in?

Pterygium. **Pterygium** - **Stocker's line** is a **ferrous deposit** that appears as a brown or yellow line at the leading edge of a **pterygium**. - Its presence signifies the progressive nature of the pterygium, indicating ongoing iron deposition due to chronic epithelial degeneration and remodeling. *Glaucoma* - Glaucoma is characterized by **optic nerve damage** and **visual field loss**, usually associated with elevated intraocular pressure. - It does not involve the formation of Stocker's line, which is a corneal or conjunctival finding. *Posterior scleritis* - Posterior scleritis is an **inflammation of the sclera** behind the equator of the globe, often presenting with pain, vision loss, or choroidal folds. - It does not involve the characteristic Stocker's line, which is specific to pterygium. *Diabetic retinopathy* - Diabetic retinopathy involves **microvascular damage** to the retina, leading to vision loss, and is characterized by microaneurysms, hemorrhages, and neovascularization. - It is a retinal disease and does not present with Stocker's line.

Q: From which surface is the Purkinje IV image formed?

Posterior surface of lens. ***Posterior surface of lens*** - The **Purkinje IV image** is formed by reflection from the **posterior surface of the lens**, which is the most curved surface in the eye. - Due to the higher curvature and refractive index difference, this surface acts as a concave mirror, producing an **inverted, virtual image**. *Anterior surface of cornea* - The **Purkinje I image** is formed from the **anterior surface of the cornea**, which is the primary reflective surface of the eye. - This image is **bright, erect, and virtual**, serving as a basic reference for eye position. *Posterior surface of cornea* - The **Purkinje II image** originates from the **posterior surface of the cornea**, a much less curved and reflective surface than the anterior. - This image is typically **fainter** and less frequently used in clinical assessments due to its reduced visibility. *Anterior surface of lens* - The **Purkinje III image** is generated by reflection from the **anterior surface of the lens**. - This image is **inverted and virtual**, and its movement relative to Purkinje I can indicate lens accommodation changes.

Q: Cicatrising trachoma is associated with which stage of the disease?

Stage-3. ***Stage-3*** - **Cicatrising trachoma** corresponds to Stage 3 of the WHO classification for trachoma, characterized by scarring of the conjunctiva. - This stage is marked by the presence of **conjunctival scarring (TS)**, which can lead to further complications. *Stage-1* - Stage 1 is characterized by **trachomatous inflammation, follicular (TF)**, indicating active infection with follicles in the upper tarsal conjunctiva. - It represents the initial, active inflammatory phase and does not involve scarring. *Stage-2* - Stage 2 is characterized by **trachomatous inflammation, intense (TI)**, where there is pronounced inflammation that obscures blood vessels. - While intense inflammation is present, significant scarring has not yet developed at this stage, differentiating it from cicatrising trachoma. *Stage-4* - Stage 4 is characterized by **trachomatous trichiasis (TT)**, where the eyelashes turn inward and rub against the cornea. - This stage is a direct complication of the scarring from Stage 3, leading to corneal damage, rather than the cicatrising stage itself.

Q: Which Goldmann type is considered the standard in perimetry?

Goldmann type III (commonly used stimulus size). ***Goldmann type III (commonly used stimulus size)*** - This stimulus size is the **international standard** for kinetic perimetry and ensures comparability of visual field charts worldwide. - It provides a balance between **sensitivity** and minimizing the effects of **pupil size** and other ocular factors. *Goldmann type I (small stimulus size)* - While very small, this stimulus type is **not the standard** for general perimetry. - It is sometimes used for detecting **subtle defects** or for patients with very good visual acuity, but its small size can make it harder to detect. *Goldmann type II (medium-small stimulus size)* - This stimulus size is **smaller than the standard** and is not universally adopted for perimetry. - It offers slightly more sensitivity than the standard but can be more affected by **refractive errors** or media opacities. *Goldmann type IV (large stimulus size)* - This stimulus is **much larger than the standard** and is typically used for detecting **gross defects** or in patients with severely impaired vision. - Its large size makes it **less sensitive** to smaller visual field abnormalities.

Q: All are parts of anterior segment of eye except?

Vitreous. ***Vitreous*** - The **vitreous humor**, or simply vitreous, is a transparent, gel-like substance that fills the space posterior to the lens and anterior to the retina, making it part of the **posterior segment** of the eye [3]. - Its main function is to maintain the shape of the eye and keep the retina in place. *Lens* - The **lens** is a transparent, biconvex structure located behind the iris and in front of the vitreous, making it a key component of the **anterior segment** [2]. - It works to focus light onto the retina, changing shape to alter the focal length of the eye. *Cornea* - The **cornea** is the transparent, outermost layer of the eye that covers the iris, pupil, and anterior chamber, clearly positioning it within the **anterior segment** [2]. - It plays a crucial role in focusing light into the eye. *Aqueous humor* - The **aqueous humor** is a clear, watery fluid located in the space between the cornea and the lens (the anterior and posterior chambers), which is definitively part of the **anterior segment** [1]. - It nourishes the cornea and lens and maintains intraocular pressure.

Question 1

Retinitis pigmentosa is characterized by ?

Accepted Answer

Loss of peripheral vision

Answer

Loss of central vision

Answer

Visual field constriction

Answer

Tubular vision

Question 2

Which of the following statements about the c-wave in electroretinogram (ERG) is most accurate?

Accepted Answer

The 'c' wave is a slow positive wave.

Answer

The 'c' wave is a negative wave.

Answer

The 'b' wave arises primarily from photoreceptors.

Answer

The 'a' wave is a positive wave.

Question 3

Arcuate field defect akin to glaucoma is seen in?

Accepted Answer

Optic nerve lesion

Answer

Pituitary adenoma

Answer

Posterior cerebral artery infarct

Answer

None of the options

Question 4

Binocular single vision is tested by?

Accepted Answer

Synoptophore

Answer

Amsler grid

Answer

Cardboard test

Answer

Maddox rod

Question 5

Stocker's line is seen in?

Accepted Answer

Pterygium

Answer

Glaucoma

Answer

Posterior scleritis

Answer

Diabetic retinopathy

Question 6

From which surface is the Purkinje IV image formed?

Accepted Answer

Posterior surface of lens

Answer

Anterior surface of cornea

Answer

Posterior surface of cornea

Answer

Anterior surface of lens

Question 7

Cicatrising trachoma is associated with which stage of the disease?

Accepted Answer

Stage-3

Answer

Stage-1

Answer

Stage-2

Answer

Stage-4

Question 8

All statements are true about trachoma except:

Accepted Answer

Marked papillary hyperplasia with limbal follicles are seen in stage III

Answer

Strains mainly responsible are A, B, Ba and C

Answer

Trachoma is caused by bedsonian organism of psittacosis - lymphogranuloma - trachoma (PLT) group.

Answer

Corneal ulceration is a complication

Question 9

Which Goldmann type is considered the standard in perimetry?

Accepted Answer

Goldmann type III (commonly used stimulus size)

Answer

Goldmann type I (small stimulus size)

Answer

Goldmann type II (medium-small stimulus size)

Answer

Goldmann type IV (large stimulus size)

Question 10

All are parts of anterior segment of eye except?

Accepted Answer

Vitreous

Answer

Lens

Answer

Cornea

Answer

Aqueous humor

NEET-PG 2013 — Ophthalmology