Head and neck: carotid sheath: practice question

A Anatomy 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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Anatomy · Head and neck: carotid sheath

Sample item

A surgeon performing carotid endarterectomy opens the carotid sheath along the anterior border of sternocleidomastoid. Which relationship of the vagus nerve is correct within the sheath?

APosterior, in the groove between the common carotid artery and internal jugular veinBLateral to the internal jugular veinCMedial to the common carotid arteryDAnterior to the common carotid artery

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

The answer and the reasoning

A. Posterior, in the groove between the common carotid artery and internal jugular vein

The carotid sheath contains the common (later internal) carotid artery medially, the internal jugular vein laterally and the vagus nerve posteriorly between them. The superior root of the ansa cervicalis is embedded in the anterior wall of the sheath. The sympathetic trunk lies behind the sheath, outside it.

Option by option

A. Posterior, in the groove between the common carotid artery and internal jugular vein (correct)
Correct. The vagus lies posteriorly between the artery and vein.
B. Lateral to the internal jugular vein
The internal jugular vein is lateral, and the vagus lies behind and between.
C. Medial to the common carotid artery
The artery is the most medial structure, and the vagus lies behind rather than medial to it.
D. Anterior to the common carotid artery
The nerve is not anterior to the artery; the ansa cervicalis lies anteriorly.

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.

Questions about this Anatomy question

What is the answer to this Anatomy question?

The best answer is A, Posterior, in the groove between the common carotid artery and internal jugular vein. The carotid sheath contains the common (later internal) carotid artery medially, the internal jugular vein laterally and the vagus nerve posteriorly between them.

Why is "Lateral to the internal jugular vein" not the answer?

The internal jugular vein is lateral, and the vagus lies behind and between.

Why is "Medial to the common carotid artery" not the answer?

The artery is the most medial structure, and the vagus lies behind rather than medial to it.

Why is "Anterior to the common carotid artery" not the answer?

The nerve is not anterior to the artery; the ansa cervicalis lies anteriorly.

What concept does this question test?

It tests Head and neck: carotid sheath in Anatomy. The superior root of the ansa cervicalis is embedded in the anterior wall of the sheath. The sympathetic trunk lies behind the sheath, outside it.

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 Head and neck: carotid sheath?

Learn every nerve by its route, its muscles and what a lesion looks like at the bedside. That one habit answers a large share of questions. Then use the flashcards and the other Anatomy 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.