KMU Past Paper Practice

Question:

A 22-year-old man with suspected keratoconus has progressive irregular refraction. The ophthalmologist wants to objectively quantify the area of greatest corneal thinning during follow-up. Which investigation is most appropriate for this purpose?

Correct Answer: Corneal pachymetry

Explanation: Pachymetry measures corneal thickness and helps document the characteristic thinning that occurs in keratoconus.

Question:

A 29-year-old man with long-standing keratoconus has severe irregularity, dense central corneal scarring and intolerance to contact lenses. His vision remains poor despite optical correction. Which management option is most appropriate?

Correct Answer: Corneal transplantation

Explanation: Advanced keratoconus with significant central scarring, poor vision and contact-lens intolerance may require corneal transplantation.

Question:

An 18-year-old student with allergic eye disease is found to have early keratoconus. He frequently rubs his eyes because of itching. Which factor in his history is most important to modify to reduce additional mechanical stress on the cornea?

Correct Answer: Repeated vigorous eye rubbing

Explanation: Repetitive eye rubbing is an important modifiable mechanical factor associated with keratoconus progression, particularly in patients with ocular allergy.

Question:

A 70-year-old man has no visual symptoms, but slit-lamp examination reveals a grey-white circumferential ring of lipid deposition near the corneal limbus. The central cornea remains clear. Which condition best explains the finding?

Correct Answer: Corneal arcus

Explanation: Corneal arcus is an acquired peripheral lipid degeneration producing a grey-white ring near the limbus while usually sparing central vision.

Question:

A 54-year-old woman with poorly controlled diabetes reports that her spectacle prescription seems to change when her blood glucose fluctuates markedly. Fundus examination shows no new retinal lesion. Which diabetic ocular effect best explains this complaint?

Correct Answer: Transient refractive change from altered glucose levels

Explanation: Marked changes in blood glucose can temporarily alter ocular refraction, causing fluctuating blur or changes in spectacle requirement.

Question:

Fundoscopy in a diabetic patient shows sharply defined yellow deposits surrounding areas of retinal thickening. Which pathological process produces these deposits?

Correct Answer: Residual lipid after chronic vascular leakage

Explanation: Hard exudates form when lipid-rich material remains in the retina after chronic leakage from damaged retinal capillaries.

Question:

A 61-year-old man with advanced proliferative diabetic retinopathy develops a dense vitreous hemorrhage that fails to clear and prevents useful vision. Which management option is most appropriate at this stage?

Correct Answer: Pars plana vitrectomy

Explanation: Vitrectomy is an important surgical option for selected advanced diabetic complications such as a non-clearing vitreous hemorrhage.

Question:

A diabetic patient has severe retinopathy. The ophthalmologist needs to identify areas of capillary non-perfusion and determine the pattern of retinal vascular leakage before further treatment planning. Which investigation provides this information best?

Correct Answer: Fluorescein angiography

Explanation: Fluorescein angiography demonstrates retinal vascular leakage and areas of capillary non-perfusion, helping assess retinal ischemia.

Question:

Fundus examination in a patient with chronic hypertension shows narrowing of a retinal vein where it crosses beneath a thickened arteriole. Which mechanism best explains this appearance?

Correct Answer: Compression of the vein by a sclerosed arteriole

Explanation: AV nicking develops when a thickened, sclerotic retinal arteriole compresses the underlying vein at an arteriovenous crossing.

Question:

A patient with severe hypertension has yellow hard exudates arranged radially around the macula, producing a star-like pattern. Which process is responsible for this appearance?

Correct Answer: Lipid-rich vascular leakage around the macula

Explanation: A macular star is formed by hard lipid exudates deposited in a radial pattern around the macula after retinal vascular leakage.

Question:

A 68-year-old man develops a central retinal vein occlusion. During assessment, the ophthalmologist reviews factors that may have contributed to impaired venous drainage through the optic nerve region. Which ocular condition is a recognized risk factor?

Correct Answer: Glaucoma with raised intraocular pressure

Explanation: Glaucoma and elevated intraocular pressure are recognized ocular risk factors for central retinal vein occlusion.

Question:

A 72-year-old patient with central retinal vein occlusion has severe visual loss. Fluorescein angiography demonstrates extensive areas of capillary non-perfusion. Which form of the disease does this finding most strongly support?

Correct Answer: Ischemic central retinal vein occlusion

Explanation: Extensive retinal capillary non-perfusion indicates the ischemic form of CRVO, which carries a higher risk of neovascular complications.

Question:

A 75-year-old man develops severe unilateral retinal ischemia from central retinal arterial obstruction. Direct light in the affected eye produces a reduced direct and consensual pupillary response compared with illumination of the normal eye. Which examination finding does this represent?

Correct Answer: Relative afferent pupillary defect

Explanation: Severe unilateral retinal ischemia reduces afferent visual input, producing a relative afferent pupillary defect in the affected eye.

Question:

A 71-year-old man develops acute retinal arterial occlusion. He has a history of carotid atherosclerotic disease and atrial fibrillation. Which etiological mechanism best fits this clinical background?

Correct Answer: Embolic disease from carotid or cardiac sources

Explanation: CRAO frequently results from embolic arterial obstruction, and carotid atherosclerosis or cardiac disease may provide the embolic source.

Question:

A patient is diagnosed with a peripheral rhegmatogenous retinal detachment. He has a field defect, but his central visual acuity remains relatively good. Which anatomical finding best explains preservation of central vision?

Correct Answer: The macula remains attached

Explanation: Central acuity may remain good while the macula is still attached; major central visual loss develops when the detachment reaches the macula.

Question:

A patient with an inflammatory choroidal disorder develops subretinal fluid and separation of the neurosensory retina. Careful examination shows no retinal tear and no significant fibrovascular traction. Which type of retinal detachment is most likely?

Correct Answer: Exudative retinal detachment

Explanation: Exudative detachment results from accumulation of subretinal fluid without a retinal break, commonly because of inflammatory or vascular leakage.

Question:

Fundus examination reveals a choroidal tumor with a characteristic collar-button configuration. Which structural event most directly produces this shape?

Correct Answer: Tumor breakthrough through Bruch membrane

Explanation: A choroidal melanoma may acquire a mushroom or collar-button shape when tumor growth breaks through Bruch membrane.

Question:

A 69-year-old patient has a very large choroidal melanoma with poor visual potential and a painful affected eye. The lesion is unsuitable for conservative eye-preserving therapy. Which management approach is most appropriate?

Correct Answer: Enucleation

Explanation: Enucleation may be required for a large choroidal melanoma, particularly when the eye is painful or conservative ocular treatment is unsuitable.

Question:

Fundoscopy in a patient with inherited retinal degeneration shows pigment clumps surrounding mid-peripheral retinal vessels in a bone-spicule pattern. Which pathological change best explains this appearance?

Correct Answer: Migration of retinal pigment epithelial cells around vessels

Explanation: Bone-spicule pigmentation in retinitis pigmentosa develops as retinal pigment epithelial cells migrate into the retina around blood vessels.

Question:

A patient with chronic intestinal malabsorption develops progressive difficulty adapting to darkness and ocular surface dryness despite an apparently adequate diet. Which mechanism most likely produced the deficiency responsible for these ocular findings?

Correct Answer: Impaired absorption of a fat-soluble vitamin

Explanation: Vitamin A is fat-soluble, so disorders causing chronic fat malabsorption can deplete body stores and lead to night blindness and xerophthalmia.