NTR University Ophthalmology MCQ Answers (July 2026) - SET B

Q1. 1 mm change in length of the eyeball leads to change in dioptric power by:

Per AK Khurana: A 1 mm change in axial length of the eyeball corresponds to approximately 3 D of refractive change. However, the most widely accepted and exam-standard answer in Khurana is 3D per mm - but among the given options, b) 2.5D is the closest and the standard answer cited in most Indian ophthalmology MCQ compilations based on Khurana. (Note: Some editions state ~3D, but 3D is not an option; 2.5D is the best available answer.)

Q2. Important feature of herpes simplex keratitis:

AK Khurana: Herpes simplex keratitis characteristically causes reduced (diminished) corneal sensitivity due to damage to the trigeminal nerve endings in the cornea. Dendritic ulcer + reduced corneal sensation = pathognomonic of HSV keratitis. Pannus is seen in trachoma; ciliary congestion and congestive haze are non-specific.

Q3. Angular conjunctivitis is caused by:

AK Khurana: Moraxella lacunata (Diplobacillus of Morax-Axenfeld) causes angular conjunctivitis, characterized by redness and maceration at the canthi (angles). The organism produces proteolytic enzymes that macerate the skin at the angles.

Q4. Junction between the retina and ciliary body is called:

AK Khurana: The ora serrata is the serrated anterior margin of the retina, marking the junction between the retina and the pars plana of the ciliary body. Pars plana is the flat posterior part of the ciliary body; pars plicata is the folded anterior part.

Q5. Nerve supply of levator palpebrae superioris:

AK Khurana: Levator palpebrae superioris (LPS) is supplied by the oculomotor nerve (CN III). The smooth muscle component (Muller's muscle) is supplied by sympathetic fibres. Ptosis in CN III palsy is due to LPS paralysis.

Q6. Dislocation of lens is seen in all the following conditions EXCEPT:

AK Khurana: Ectopia lentis (lens dislocation) is associated with:

• Marfan syndrome (upward and outward dislocation)
• Homocystinuria (downward and inward dislocation)
• Marchesani's syndrome (microspherophakia with subluxation)

Congenital rubella causes cataract (pearly white nuclear cataract), NOT lens dislocation. So the exception is congenital rubella.

Q7. Treatment of dacryocystitis in a 3-month-old child:

AK Khurana: In a neonate/infant under 6 months with congenital nasolacrimal duct obstruction (NLDO) / dacryocystitis, the first-line treatment is Crigler's massage (pressure massage of the lacrimal sac). Probing is done only if massage fails after 6-12 months. Massaging empties the sac and helps open the membranous obstruction at the lower end.

Q8. Krukenberg spindle is associated with:

AK Khurana: Krukenberg spindle is a vertical spindle-shaped deposition of pigment granules on the posterior corneal endothelium. It is the hallmark of pigmentary glaucoma (and pigment dispersion syndrome). Pigment from the iris rubs off onto the lens zonules and is phagocytosed by the trabecular meshwork, raising IOP.

Q9. Muscles responsible for accommodation are innervated through nerves passing via:

AK Khurana: The Edinger-Westphal nucleus (accessory parasympathetic nucleus of CN III) sends preganglionic fibres that relay in the ciliary ganglion. Postganglionic fibres supply the ciliary muscle (accommodation) and the sphincter pupillae (miosis). The near reflex (accommodation-convergence-miosis) is mediated through this nucleus.

Q10. Complication of prolonged use of corticosteroid eye drops:

AK Khurana: Prolonged use of corticosteroids (topical or systemic) causes posterior subcapsular cataract (PSC). Steroids inhibit lens epithelial cell migration and cause accumulation of abnormal protein in the posterior subcapsular region. This is a classic exam fact.

Q11. Cherry red spot on retina is seen in all EXCEPT:

AK Khurana: Cherry red spot is seen in:

• CRAO (Central Retinal Artery Occlusion) - the fovea receives choroidal supply, so it appears red against pale ischemic retina
• Tay-Sachs disease (GM2 gangliosidosis)
• Niemann-Pick disease (sphingomyelin storage)
• Sandhoff disease, Farber disease, Gaucher disease

CRVO (Central Retinal Vein Occlusion) causes flame-shaped hemorrhages, dilated tortuous veins, disc edema - NOT a cherry red spot. So the exception is CRVO.

Q12. Aqueous humor in the eye is secreted by:

AK Khurana: Aqueous humor is secreted by the non-pigmented epithelium of the ciliary processes (pars plicata) of the ciliary body. The non-pigmented layer is the inner layer (facing the posterior chamber) and is metabolically active in aqueous production via active secretion, ultrafiltration, and simple diffusion.

Q13. The sclera is thinnest at:

AK Khurana: The sclera is thinnest (0.3 mm) just posterior to the insertion of the rectus muscles. This is why perforations during strabismus surgery are a risk at this site. Other thicknesses: at equator ~0.4-0.5 mm, near optic nerve ~1 mm (thickest).

Q14. Stye is inflammation of:

AK Khurana: A stye (external hordeolum) is an acute staphylococcal infection of the gland of Zeis (sebaceous gland of eyelash follicle) or Moll's gland. Internal hordeolum is infection of the Meibomian gland. Chalazion is a chronic granulomatous inflammation of the Meibomian gland.

Q15. Protozoa that affects the eye:

AK Khurana: Toxoplasma gondii is the most common protozoan cause of posterior uveitis / retinochoroiditis. It causes focal necrotizing retinochoroiditis, often near old scars. Congenital toxoplasmosis: classic triad of chorioretinitis, hydrocephalus, and intracranial calcification. E. histolytica and Giardia primarily affect the GI tract.

Q16. A muddy appearance of iris is seen in:

AK Khurana: In iridocyclitis (anterior uveitis), the iris appears muddy, dull, and discolored due to edema and engorgement of iris vessels with cellular infiltration. Other signs include ciliary congestion, flare and cells in AC, keratic precipitates, and posterior synechiae.

Q17. A girl has pain and blurring of vision while reading:

AK Khurana: Asthenopia (eye strain) presents with headache, pain in and around the eyes, and blurring of vision especially on prolonged near work (reading). It is typically due to uncorrected refractive errors (hypermetropia, astigmatism) or imbalance of ocular muscles. The near effort to overcome the refractive error fatigues the ciliary muscle.

Q18. Which field of vision has the maximum extent?

AK Khurana: The temporal field has the maximum extent - approximately 90 degrees from fixation. The nasal field is ~60°, superior ~50°, inferior ~70°. The temporal field is widest because the nasal retina (which sees the temporal field) has a wider expanse and the nose does not obstruct it.

Q19. Presence of an extra row of cilia posterior to the grey line:

AK Khurana: Distichiasis is the presence of an accessory row of eyelashes arising from or near the Meibomian gland orifices, posterior to the grey line. These lashes are directed toward the cornea and can cause corneal irritation. Trichiasis = misdirected normal lashes; Poliosis = white lashes; Madarosis = loss of lashes.

Q20. Colour blindness is transmitted through:

AK Khurana: Colour blindness (red-green, most common form - Daltonism) is inherited as an X-linked recessive trait. It affects males more (1 in 12) than females (1 in 200). Females are carriers. Males cannot transmit to sons (no X-linked male-to-male transmission). The gene is located on the X chromosome.

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