Neuroimaging: artery of Percheron infarct: practice question

A Radiology 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

Radiology · Neuroimaging: artery of Percheron infarct

Sample item

A patient wakes up drowsy with a vertical gaze palsy and memory loss. MRI shows bilateral paramedian thalamic diffusion restriction with a midbrain extension. What is the most likely cause?

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

The answer and the reasoning

A. Occlusion of the artery of Percheron

The artery of Percheron is a single trunk from a posterior cerebral artery that supplies both paramedian thalami and the rostral midbrain. Its occlusion causes bilateral infarcts with hypersomnolence, vertical gaze palsy and amnesia.

Option by option

  • A. Occlusion of the artery of Percheron (correct)

    Correct. Bilateral paramedian thalamic infarcts with midbrain involvement indicate a Percheron occlusion.

  • B. Deep cerebral venous thrombosis

    Deep venous thrombosis causes bilateral thalamic oedema, often with haemorrhage and venous clot on venography.

  • C. Bilateral lenticulostriate occlusion

    Lenticulostriate occlusion causes basal ganglia lacunes, not paramedian thalamic infarcts.

  • D. Wernicke encephalopathy

    Wernicke encephalopathy follows thiamine deficiency and affects the mamillary bodies and periaqueductal region.

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 Radiology questions

Questions about this Radiology question

What is the answer to this Radiology question?

The best answer is A, Occlusion of the artery of Percheron. The artery of Percheron is a single trunk from a posterior cerebral artery that supplies both paramedian thalami and the rostral midbrain.

Why is "Deep cerebral venous thrombosis" not the answer?

Deep venous thrombosis causes bilateral thalamic oedema, often with haemorrhage and venous clot on venography.

Why is "Bilateral lenticulostriate occlusion" not the answer?

Lenticulostriate occlusion causes basal ganglia lacunes, not paramedian thalamic infarcts.

Why is "Wernicke encephalopathy" not the answer?

Wernicke encephalopathy follows thiamine deficiency and affects the mamillary bodies and periaqueductal region.

What concept does this question test?

It tests Neuroimaging: artery of Percheron infarct in Radiology. Its occlusion causes bilateral infarcts with hypersomnolence, vertical gaze palsy and amnesia.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. 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 Neuroimaging: artery of Percheron infarct?

Learn signs with the image, and the disease they point to. Then use the flashcards and the other Radiology 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.