KMU Past Paper Practice

Question:

A 24-year-old woman develops subacute monocular visual loss. She reports aching behind the eye that becomes worse whenever she looks from side to side. Colour vision is impaired, but the optic disc appears normal. Which mechanism best explains the ocular pain?

Options:

Correct Answer: Movement-related traction around an inflamed retrobulbar optic nerve

Explanation: In retrobulbar optic neuritis, movement of the globe can mechanically stress tissues around the inflamed optic nerve, producing characteristic pain on eye movement.

Question:

A 28-year-old woman has recovered substantially from a first episode of clinically typical optic neuritis. MRI demonstrates several cerebral white-matter lesions compatible with demyelination. Which additional management principle is most appropriate?

Options:

Correct Answer: Neurological assessment for associated demyelinating disease

Explanation: Cerebral demyelinating lesions suggest that the optic neuritis may be part of a wider central nervous system disorder, so neurological evaluation and follow-up are appropriate.

Question:

A young adult has optic-nerve dysfunction with disc swelling and a macular star. The presentation does not resemble ordinary demyelinating optic neuritis. Which clinical approach best addresses the likely underlying process?

Options:

Correct Answer: Targeted evaluation for an infectious or inflammatory cause

Explanation: A neuroretinitis pattern should prompt evaluation for relevant infectious or inflammatory causes rather than being managed automatically as typical demyelinating optic neuritis.

Question:

A patient recovering from optic neuritis can read most letters on the visual-acuity chart but says that objects remain less distinct and appear to blend into their background. Which visual function is most likely still impaired?

Options:

Correct Answer: Contrast sensitivity

Explanation: Optic-nerve dysfunction can reduce contrast sensitivity even when Snellen acuity has substantially recovered, so patients may still perceive objects as less distinct.

Question:

A 25-year-old patient has recurrent inflammatory optic-nerve attacks with prominent disc swelling and a clinical pattern considered atypical for ordinary multiple-sclerosis-associated optic neuritis. Which additional immune-mediated disorder belongs in the differential?

Options:

Correct Answer: MOG-antibody-associated disease

Explanation: MOG-antibody-associated disease is an immune-mediated demyelinating disorder that can present with recurrent or atypical optic neuritis and therefore merits consideration in an atypical pattern.

Question:

A 22-year-old man has genetically confirmed Leber hereditary optic neuropathy. He asks what modifiable lifestyle advice is relevant while his family receives counselling. Which recommendation is most appropriate?

Options:

Correct Answer: Avoid smoking and excessive alcohol intake

Explanation: Smoking and excessive alcohol may increase mitochondrial stress and are important avoidable exposures in patients or carriers with mitochondrial optic neuropathy.

Question:

Two siblings have bilateral painless central visual impairment and optic-disc pallor. Their ophthalmologist suspects an inherited optic neuropathy and wants to establish the diagnosis while providing accurate advice to other family members. Which investigation is most useful for this purpose?

Options:

Correct Answer: Genetic testing with family counselling

Explanation: Genetic testing can confirm a suspected hereditary optic neuropathy and provides a basis for appropriate counselling regarding inheritance and affected relatives.

Question:

A patient with a hereditary optic neuropathy has stable but permanent bilateral central visual loss despite completion of diagnostic assessment. The impairment significantly affects reading and daily activities. Which supportive measure is most appropriate?

Options:

Correct Answer: Low-vision rehabilitation

Explanation: Once irreversible axonal loss has produced permanent central visual impairment, low-vision rehabilitation helps maximize the patient’s remaining functional vision.

Question:

A patient with previous gastrointestinal surgery develops painless bilateral central visual loss and centrocecal scotomas. Vitamin B12 and folate levels are not deficient. Which additional nutritional abnormality should be considered from the causes covered in this topic?

Options:

Correct Answer: Copper deficiency

Explanation: Copper deficiency is a recognized nutritional cause of optic neuropathy, particularly in appropriate malabsorptive or post-gastrointestinal-surgery settings.

Question:

A malnourished patient has bilateral dyschromatopsia and symmetrical centrocecal visual-field defects. Which anatomical fibre group is preferentially involved and best explains this pattern?

Options:

Correct Answer: Papillomacular bundle fibres

Explanation: Nutritional and toxic optic neuropathies preferentially damage fibres serving central vision, particularly the papillomacular bundle, producing central or centrocecal defects.

Question:

A 52-year-old man with long-standing heavy alcohol intake has poor dietary intake and gradually progressive bilateral central visual impairment. Which aspect of his history most directly increases the likelihood of a nutritional optic neuropathy?

Options:

Correct Answer: Alcohol misuse associated with poor nutrition

Explanation: Chronic alcohol misuse may coexist with significant dietary deficiency, creating the metabolic conditions that predispose to nutritional optic-nerve dysfunction.

Question:

A patient with raised intracranial pressure develops swelling of both optic nerve heads. Which anatomical relationship best explains why the process commonly affects both eyes?

Options:

Correct Answer: The optic-nerve subarachnoid spaces communicate with intracranial cerebrospinal fluid

Explanation: The optic nerves are surrounded by meninges and subarachnoid space, allowing raised cerebrospinal fluid pressure to be transmitted to both optic nerve heads.

Question:

A patient has approximately symmetrical bilateral papilledema. Visual acuity is relatively preserved and both pupils are equal. Which finding is most likely on the swinging-flashlight test?

Options:

Correct Answer: No significant relative afferent pupillary defect

Explanation: RAPD compares afferent function between the two eyes. When papilledema affects both optic nerves symmetrically, a significant relative difference may not be present.

Question:

Fundoscopy of a patient with established papilledema shows elevated hyperemic optic discs with blurred margins. Which additional optic-disc change is expected as swelling becomes more pronounced?

Options:

Correct Answer: Reduction or obscuration of the physiological cup

Explanation: Swollen nerve fibres elevate the optic nerve head and fill the normal central excavation, making the physiological cup shallow or difficult to see.

Question:

During fundus examination of a patient with severe disc edema, parts of the retinal vessels become difficult to follow as they cross the edge of the optic nerve head. Which process best explains this appearance?

Options:

Correct Answer: Swollen nerve fibres obscuring vessels at the disc margin

Explanation: Edematous axons elevate and blur the optic nerve head, so vessels crossing the swollen disc margin may become partly obscured.

Question:

A patient with meningeal inflammation develops headache and bilateral optic-disc edema. Which mechanism most reasonably links the intracranial inflammatory process to the ocular finding?

Options:

Correct Answer: Impaired cerebrospinal fluid circulation or absorption

Explanation: Meningeal inflammation can disturb CSF circulation or absorption, raising intracranial pressure and consequently producing papilledema.

Question:

A child with hydrocephalus develops bilateral papilledema. Which physiological change is responsible for transmitting the neurological disorder into the characteristic fundus finding?

Options:

Correct Answer: Increased cerebrospinal fluid volume and pressure

Explanation: Hydrocephalus raises intracranial pressure by increasing cerebrospinal fluid volume, and this pressure is transmitted along the optic-nerve sheaths to the discs.

Question:

A patient with confirmed papilledema is being followed after treatment of raised intracranial pressure. The clinician wants an objective structural method to document changes in optic-nerve-head and retinal nerve-fibre swelling over time. Which test best serves this purpose?

Options:

Correct Answer: Serial optical coherence tomography

Explanation: OCT can quantify structural changes in the optic nerve head and retinal nerve-fibre layer, making it useful for follow-up, although it does not identify the intracranial cause.

Question:

A young woman has headache, pulsatile tinnitus and papilledema. Appropriate investigation excludes an intracranial mass, hydrocephalus and another secondary structural cause, and idiopathic intracranial hypertension is diagnosed. Which management combination is appropriate at undergraduate level?

Options:

Correct Answer: Weight reduction where relevant with acetazolamide therapy

Explanation: Management of idiopathic intracranial hypertension aims to reduce intracranial pressure; weight reduction when relevant and acetazolamide are key undergraduate principles.

Question:

A patient with papilledema is receiving medical treatment for raised intracranial pressure. Despite therapy, serial assessment shows continuing deterioration of visual function. Which broad management principle is most appropriate to prevent irreversible optic-nerve damage?

Options:

Correct Answer: Consider urgent pressure-lowering procedures such as CSF diversion or optic-nerve-sheath fenestration

Explanation: Progressive visual dysfunction despite medical treatment indicates threatened vision; selected patients require urgent procedures that lower intracranial pressure or directly protect the optic nerve.