Radiation safety: operator dose in fluoroscopy: 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 · Radiation safety: operator dose in fluoroscopy

Sample item

In a fluoroscopy room, where is scattered radiation dose to the operator greatest?

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

The answer and the reasoning

A. On the side of the patient where the X-ray beam enters, near the tube

Scatter arises mainly at the beam entrance surface of the patient, so intensity is highest on the tube side, and lower on the detector side where the patient attenuates the beam. Lateral projections increase scatter on the tube side. Distance, shielding and reduced exposure time lower the dose.

Option by option

  • A. On the side of the patient where the X-ray beam enters, near the tube (correct)

    Correct. Entrance-side scatter is highest near the tube.

  • B. On the side of the image receptor

    The detector side receives less scatter because the patient attenuates it.

  • C. At a distance of several metres

    Dose falls with distance.

  • D. Behind a lead screen

    A lead screen reduces the dose.

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, On the side of the patient where the X-ray beam enters, near the tube. Scatter arises mainly at the beam entrance surface of the patient, so intensity is highest on the tube side, and lower on the detector side where the patient attenuates the beam.

Why is "On the side of the image receptor" not the answer?

The detector side receives less scatter because the patient attenuates it.

Why is "At a distance of several metres" not the answer?

Dose falls with distance.

Why is "Behind a lead screen" not the answer?

A lead screen reduces the dose.

What concept does this question test?

It tests Radiation safety: operator dose in fluoroscopy in Radiology. Lateral projections increase scatter on the tube side. Distance, shielding and reduced exposure time lower the dose.

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 Radiation safety: operator dose in fluoroscopy?

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.