Cranial nerves: sixth nerve palsy: 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.

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Ophthalmology · Cranial nerves: sixth nerve palsy

Sample item

A patient has horizontal diplopia worse on looking to the left, with an inability to abduct the left eye. Which muscle is paralysed?

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

The answer and the reasoning

C. Left lateral rectus

The abducens nerve supplies the lateral rectus. Its palsy produces an esotropia that increases on gaze to the affected side, and it is also a false localising sign in raised intracranial pressure.

Option by option

  • A. Left medial rectus

    The medial rectus adducts the eye.

  • B. Left superior oblique

    The superior oblique causes vertical diplopia.

  • C. Left lateral rectus (correct)

    Correct. Failure of abduction means a lateral rectus palsy.

  • D. Right lateral rectus

    The right lateral rectus acts on the right eye.

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, Left lateral rectus. The abducens nerve supplies the lateral rectus.

Why is "Left medial rectus" not the answer?

The medial rectus adducts the eye.

Why is "Left superior oblique" not the answer?

The superior oblique causes vertical diplopia.

Why is "Right lateral rectus" not the answer?

The right lateral rectus acts on the right eye.

What concept does this question test?

It tests Cranial nerves: sixth nerve palsy in Ophthalmology. Its palsy produces an esotropia that increases on gaze to the affected side, and it is also a false localising sign in raised intracranial pressure.

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 Cranial nerves: sixth nerve palsy?

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.