Lens and cataract: index myopia in nuclear sclerosis: practice question

A Ophthalmology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Ophthalmology · Lens and cataract: index myopia in nuclear sclerosis

Sample item

A 68-year-old presbyope notices that she can read without her reading glasses, but her distance vision has become worse. Slit lamp shows brunescent nuclear lens changes. What explains the improved near vision?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

C. Increased refractive index of the nucleus causing myopic shift

Progressive nuclear sclerosis raises the refractive index of the lens core and shifts refraction toward myopia, giving temporary good near vision called second sight. This also explains the poor distance vision.

Option by option

  • A. Axial elongation of the globe

    The axial length does not change in senile cataract.

  • B. Spasm of accommodation

    Accommodation weakens with age and does not spasm in cataract.

  • C. Increased refractive index of the nucleus causing myopic shift (correct)

    Correct. A rise in nuclear refractive index causes index myopia.

  • D. Corneal steepening

    Corneal steepening is not a feature of nuclear sclerosis.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More Ophthalmology questions

Questions about this Ophthalmology question

What is the answer to this Ophthalmology question?

The best answer is C, Increased refractive index of the nucleus causing myopic shift. Progressive nuclear sclerosis raises the refractive index of the lens core and shifts refraction toward myopia, giving temporary good near vision called second sight.

Why is "Axial elongation of the globe" not the answer?

The axial length does not change in senile cataract.

Why is "Spasm of accommodation" not the answer?

Accommodation weakens with age and does not spasm in cataract.

Why is "Corneal steepening" not the answer?

Corneal steepening is not a feature of nuclear sclerosis.

What concept does this question test?

It tests Lens and cataract: index myopia in nuclear sclerosis in Ophthalmology. This also explains the poor distance vision.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Lens and cataract: index myopia in nuclear sclerosis?

Group the red eye by what to examine and what the pupil does. Then use the flashcards and the other Ophthalmology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.