KMU Past Paper Practice

MCQ 1

Question:

A 20-year-old student has visual acuity of 6/6 in both eyes but repeatedly fails to identify numbers on Ishihara plates during a routine ophthalmic examination. Which visual function is being assessed by this test?

Contrast detection

Red-green colour discrimination

Near accommodation

Brightness adaptation

Fine spatial resolution

Correct Answer: Red-green colour discrimination

Explanation: Ishihara plates primarily assess red-green colour vision. Normal Snellen acuity does not exclude a colour-vision abnormality.

MCQ 2

Question:

During a visual-function demonstration, two identical white targets have the same shape and contrast, but one is illuminated more strongly and appears brighter. Which component of vision accounts most directly for this difference?

Colour discrimination

Spatial resolution

Accommodation

Ability to perceive luminance intensity

Meridional refraction

Correct Answer: Ability to perceive luminance intensity

Explanation: Brightness perception reflects the visual response to the intensity of light reaching the retina, distinct from acuity, colour and contrast.

MCQ 3

Question:

A 24-year-old man undergoes automated refraction followed by retinoscopy. The examiner then repeatedly compares different lenses and asks which gives the clearest vision before issuing the spectacle prescription. What is this final stage called?

Subjective refraction

Cycloplegic refraction

Objective refraction

Contrast assessment

Dark adaptation testing

Correct Answer: Subjective refraction

Explanation: Subjective refraction uses the patient’s responses to refine the objectively estimated refractive error into the clearest practical prescription.

MCQ 4

Question:

During an optics teaching session, a converging spectacle lens is shown to have a focal length of 0.5 metre. What is the refractive power of this lens?

−4.0 diopters

−2.0 diopters

+0.5 diopters

+4.0 diopters

+2.0 diopters

Correct Answer: +2.0 diopters

Explanation: Lens power in diopters equals 1 divided by focal length in metres. A converging lens with a 0.5 m focal length therefore has +2 D power.

MCQ 5

Question:

A 22-year-old student complains mainly of difficulty reading the lecturer’s writing from the back of the hall but can use his mobile phone comfortably without spectacles. A 50-year-old colleague has the opposite problem, with good distance vision but increasing difficulty reading the phone. Which diagnosis best fits the younger student?

Presbyopia

Aphakia

Myopia

Hypermetropia

Pseudophakia

Correct Answer: Myopia

Explanation: Myopia predominantly impairs distance vision while near vision remains relatively better. Presbyopia produces the reverse pattern of age-related near difficulty.

MCQ 6

Question:

A 21-year-old woman has clear distance vision during routine testing but complains of recurrent eyestrain after prolonged close work. Refraction shows that her eye has insufficient optical power relative to its axial length, yet she can partly overcome this while young. Which state best explains the findings?

Myopia with reduced convergence

Hypermetropia with accommodative compensation

Astigmatism with irregular meridians

Presbyopia with reduced near addition

Aphakia with absent lens power

Correct Answer: Hypermetropia with accommodative compensation

Explanation: Young hypermetropic patients can use accommodation to add refractive power and maintain clarity, although sustained effort may produce asthenopic symptoms.

MCQ 7

Question:

Two patients are reviewed in the refraction clinic. One eye has different refractive powers in its horizontal and vertical meridians. Another patient has a markedly different refractive state in the right eye compared with the left eye. Which statement correctly distinguishes these conditions?

Both findings represent presbyopia

Both findings represent anisometropia

Both findings represent astigmatism

Astigmatism involves the two eyes; anisometropia involves accommodation

Astigmatism involves meridians; anisometropia involves the two eyes

Correct Answer: Astigmatism involves meridians; anisometropia involves the two eyes

Explanation: Astigmatism is unequal refractive power between meridians of an eye, whereas anisometropia is a refractive difference between the two eyes.

MCQ 8

Question:

A 67-year-old patient underwent removal of the crystalline lens several years ago without implantation of an intraocular lens. Compared with a pseudophakic eye, why does this eye require much greater additional converging power for clear vision?

Aphakia causes major loss of ocular positive power

Aphakia increases corneal curvature substantially

Pseudophakia removes the refractive power of the cornea

Pseudophakia increases the axial length of the eye

Aphakia increases retinal contrast sensitivity

Correct Answer: Aphakia causes major loss of ocular positive power

Explanation: The natural lens contributes substantial converging power. In pseudophakia this power is replaced by an IOL, whereas in aphakia it is absent.

MCQ 9

Question:

A 53-year-old physician already requires spectacles for distance vision and now needs additional correction for reading clinical notes. He prefers a single pair of spectacles that provides a gradual transition between distance and near viewing. Which option best meets this requirement?

Simple minus spectacles

Simple cylindrical spectacles

Plano protective spectacles

Progressive-addition spectacles

Prismatic spectacles

Correct Answer: Progressive-addition spectacles

Explanation: Progressive lenses combine distance and increasing near-addition power within one lens, providing correction for presbyopia without separate reading spectacles.

MCQ 10

Question:

A 32-year-old patient has blurred and distorted vision. Refraction cannot identify two orderly principal meridians, and conventional cylindrical spectacles fail to provide a satisfactory image. Which optical abnormality is most likely?

Simple myopia

Simple hypermetropia

Irregular astigmatism

Presbyopia

Anisometropia

Correct Answer: Irregular astigmatism

Explanation: Irregular astigmatism lacks orderly principal meridians, so a simple cylindrical spectacle lens cannot fully neutralize the variable optical power.

MCQ 11

Question:

A patient with retinal vascular disease requires an investigation to demonstrate the sequence of blood flow through retinal vessels and identify areas with impaired perfusion. Which information is Fundus Fluorescein Angiography most suited to provide?

Retinal vascular filling and perfusion

Axial length of the globe

Crystalline-lens refractive power

Extraocular-muscle movement

Corneal meridional curvature

Correct Answer: Retinal vascular filling and perfusion

Explanation: FFA records fluorescein transit through retinal circulation, helping demonstrate vascular filling, non-perfusion and related retinal vascular abnormalities.

MCQ 12

Question:

A patient with retinal vascular pathology undergoes fluorescein angiography because the ophthalmologist wants to identify abnormal escape of dye from retinal vessels. Which angiographic feature provides this information?

Change in axial length

Loss of accommodation

Altered lens curvature

Areas of fluorescein leakage

Altered corneal power

Correct Answer: Areas of fluorescein leakage

Explanation: Abnormal fluorescein leakage indicates loss of vascular integrity and is an important use of FFA in retinal vascular assessment.

MCQ 13

Question:

A 70-year-old patient has a dense media opacity that prevents direct visualization of the fundus. The ophthalmologist needs to assess the posterior segment for major structural abnormalities. Which investigation is most appropriate?

Fundus fluorescein angiography

Ocular ultrasonography

Ishihara colour testing

Subjective refraction

Contrast-sensitivity testing

Correct Answer: Ocular ultrasonography

Explanation: Ultrasonography can evaluate structures behind opaque ocular media because sound waves do not require a clear optical pathway to the fundus.

MCQ 14

Question:

A patient presents with sudden visual loss and dense vitreous haemorrhage obscuring the retinal view. The ophthalmologist wants to determine whether a retinal detachment is present behind the haemorrhage. Which investigation provides the most useful structural information?

Colour-plate testing

Cycloplegic refraction

Contrast-sensitivity testing

Fundus fluorescein angiography

B-scan ultrasonography

Correct Answer: B-scan ultrasonography

Explanation: B-scan ultrasonography is useful for detecting major posterior-segment structures such as a retinal detachment when the fundus cannot be seen directly.

MCQ 15

Question:

A young patient has moderate myopia in one eye and mild hypermetropia in the other. Refraction of each eye is internally regular, with no significant difference between its principal meridians. Which term best describes the overall refractive relationship?

Regular astigmatism

Irregular astigmatism

Anisometropia

Presbyopia

Pseudophakia

Correct Answer: Anisometropia

Explanation: Anisometropia refers to unequal refractive states between the two eyes; astigmatism refers instead to unequal refractive power between meridians.

MCQ 16

Question:

Two patients undergo cataract extraction. One is left without a replacement lens, while the other receives an intraocular lens of appropriate power. Which optical feature most clearly distinguishes the second patient from the first?

The cornea no longer refracts light

The axial length becomes shorter

Physiological accommodation becomes stronger

Lost lens power is substantially replaced by the IOL

Retinal colour perception is increased

Correct Answer: Lost lens power is substantially replaced by the IOL

Explanation: Pseudophakia restores much of the positive refractive power removed with the natural lens, whereas aphakia leaves this major optical deficit uncorrected internally.

MCQ 17

Question:

During examination, a student is asked to distinguish two targets that have identical colour, size and contrast but are presented at different illumination intensities. Which visual function is being isolated most directly?

Light brightness perception

Colour discrimination

Visual acuity

Accommodation

Meridional focusing

Correct Answer: Light brightness perception

Explanation: When colour, contrast and spatial detail are controlled, perceived differences caused by illumination intensity primarily assess brightness perception.

MCQ 18

Question:

A 26-year-old hypermetropic patient receives appropriate plus spectacles. Besides improving focus, the patient notices that prolonged reading produces less ocular fatigue. Which optical effect best explains this improvement?

The spectacles increase axial length

The spectacles reduce retinal cone activity

The spectacles produce meridional distortion

The spectacles reduce corneal transparency

Hypermetropic correction reduces accommodative demand

Correct Answer: Hypermetropic correction reduces accommodative demand

Explanation: Plus lenses supply part of the converging power that a hypermetropic patient otherwise generates through accommodation, thereby reducing accommodative strain.

MCQ 19

Question:

A patient has both a spherical refractive error and regular astigmatism. Subjective refraction shows that overall focus improves with spherical power, but one principal meridian still requires additional correction. Which prescription principle is most appropriate?

A near addition without distance correction

A cylindrical component added to spherical correction

A prismatic component without spherical power

Equal additional spherical power in all meridians

Occlusion instead of optical correction

Correct Answer: A cylindrical component added to spherical correction

Explanation: Sphero-cylindrical correction addresses both the overall spherical error and the additional difference in refractive power between principal meridians.

MCQ 20

Question:

A 29-year-old patient with corneal irregularity has significant optical distortion. Ordinary spectacles provide limited improvement because refractive power varies across the corneal surface. Which non-surgical optical approach may provide better correction in a suitable patient?

Simple plus spectacles

Simple minus spectacles

Contact-lens correction

Near-addition spectacles

Prismatic spectacles

Correct Answer: Contact-lens correction

Explanation: Selected contact lenses can provide a more regular refracting surface and may improve vision when irregular corneal astigmatism is poorly corrected by spectacles.