Chest imaging: pulmonary artery sling: 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 · Chest imaging: pulmonary artery sling

Sample item

An infant has stridor and wheeze. A barium swallow shows an anterior indentation on the oesophagus just above the carina, and CT shows the left pulmonary artery arising from the right pulmonary artery. What is the diagnosis?

ATracheo-oesophageal fistulaBPulmonary artery slingCRight aortic arch with aberrant left subclavian arteryDDouble aortic arch

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

The answer and the reasoning

B. Pulmonary artery sling

In a pulmonary artery sling, the left pulmonary artery loops between the trachea and oesophagus, which makes an anterior oesophageal indentation and compresses the trachea. It is the only vascular ring-like anomaly that indents the oesophagus anteriorly.

Option by option

A. Tracheo-oesophageal fistula
A fistula would be shown as contrast entering the trachea.
B. Pulmonary artery sling (correct)
Correct. An anterior oesophageal indent with an aberrant left pulmonary artery is a sling.
C. Right aortic arch with aberrant left subclavian artery
A right arch with aberrant subclavian causes a posterior indentation.
D. Double aortic arch
A double aortic arch gives bilateral indentations with a posterior oesophageal one.

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 Radiology question

What is the answer to this Radiology question?

The best answer is B, Pulmonary artery sling. In a pulmonary artery sling, the left pulmonary artery loops between the trachea and oesophagus, which makes an anterior oesophageal indentation and compresses the trachea.

Why is "Tracheo-oesophageal fistula" not the answer?

A fistula would be shown as contrast entering the trachea.

Why is "Right aortic arch with aberrant left subclavian artery" not the answer?

A right arch with aberrant subclavian causes a posterior indentation.

Why is "Double aortic arch" not the answer?

A double aortic arch gives bilateral indentations with a posterior oesophageal one.

What concept does this question test?

It tests Chest imaging: pulmonary artery sling in Radiology. It is the only vascular ring-like anomaly that indents the oesophagus anteriorly.

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 Chest imaging: pulmonary artery sling?

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.