Free ophthalmology MCQ exam model for clinical students

Explanation:

• Myopia → Correct because it is the most frequently encountered refractive error.

• Hypermetropia → Incorrect because it is less common.

• Astigmatism → Incorrect because it is often associated but not most common alone.

• Presbyopia → Incorrect because it is age-related.

• Anisometropia → Incorrect because it is unequal refractive error.

Explanation:

• Trabecular meshwork → Correct because it drains aqueous humor into Schlemm’s canal.

• Ciliary body → Incorrect because it produces aqueous humor.

• Lens → Incorrect because it focuses light.

• Iris → Incorrect because it regulates pupil size.

• Vitreous body → Incorrect because it maintains globe shape.

Explanation:

• Glaucoma → Correct because raised intraocular pressure damages the optic nerve.

• Uveitis → Incorrect because it may reduce intraocular pressure.

• Conjunctivitis → Incorrect because it affects conjunctiva only.

• Keratitis → Incorrect because it affects cornea.

• Retinal detachment → Incorrect because pressure is usually normal.

Explanation:

• Tonometry → Correct because it directly measures intraocular pressure.

• Ophthalmoscopy → Incorrect because it examines the fundus.

• Perimetry → Incorrect because it assesses visual fields.

• Retinoscopy → Incorrect because it measures refractive error.

• Slit-lamp examination → Incorrect because it examines anterior segment.

Explanation:

• Peripheral vision loss → Correct because glaucoma initially affects peripheral fields.

• Central scotoma → Incorrect because central vision is affected late.

• Temporal hemianopia → Incorrect because it is due to optic tract lesions.

• Altitudinal defect → Incorrect because it occurs later.

• Bitemporal hemianopia → Incorrect because it occurs in optic chiasm lesions.

Explanation:

• Macula → Correct because it contains the fovea, which provides highest visual acuity.

• Optic disc → Incorrect because it is a blind spot with no photoreceptors.

• Choroid → Incorrect because it provides vascular supply.

• Sclera → Incorrect because it provides structural support.

• Lens capsule → Incorrect because it surrounds the lens only.

Explanation:

• Vitamin A → Correct because it is required for rhodopsin synthesis in rods.

• Vitamin B₁ → Incorrect because it affects nerves.

• Vitamin C → Incorrect because it is an antioxidant.

• Vitamin D → Incorrect because it regulates calcium.

• Vitamin K → Incorrect because it is involved in clotting.

Explanation:

• Lateral rectus → Correct because it abducts the eyeball.

• Superior rectus → Incorrect because it elevates the eye.

• Inferior rectus → Incorrect because it depresses the eye.

• Medial rectus → Incorrect because it adducts the eye.

• Superior oblique → Incorrect because it intorts and depresses.

Explanation:

• Cataract → Correct because lens opacity is the leading cause of preventable blindness globally.

• Glaucoma → Incorrect because it causes irreversible blindness.

• Diabetic retinopathy → Incorrect because it is less common worldwide.

• Trachoma → Incorrect because it is declining globally.

• Age-related macular degeneration → Incorrect because it is common in elderly but not preventable.