Procedures: selective photothermolysis: practice question

A Dermatology 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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Dermatology · Procedures: selective photothermolysis

Sample item

A patient with a decorative black tattoo seeks removal. Which laser principle and device is most appropriate?

AQ-switched laser using selective photothermolysis of pigmentBPulsed dye laser at 585 nm for black inkCTopical hydroquinoneDCarbon dioxide laser ablation of the entire dermis

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

The answer and the reasoning

A. Q-switched laser using selective photothermolysis of pigment

Q-switched lasers deliver nanosecond pulses that shatter tattoo pigment particles, which are then cleared by macrophages. Different wavelengths are needed for different ink colours, and several sessions are required.

Option by option

A. Q-switched laser using selective photothermolysis of pigment (correct)
Correct. Q-switched lasers are standard for tattoo removal.
B. Pulsed dye laser at 585 nm for black ink
A pulsed dye laser targets haemoglobin, as in port-wine stains.
C. Topical hydroquinone
Hydroquinone cannot remove dermal pigment.
D. Carbon dioxide laser ablation of the entire dermis
CO2 ablation would scar.

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 Dermatology question

What is the answer to this Dermatology question?

The best answer is A, Q-switched laser using selective photothermolysis of pigment. Q-switched lasers deliver nanosecond pulses that shatter tattoo pigment particles, which are then cleared by macrophages.

Why is "Pulsed dye laser at 585 nm for black ink" not the answer?

A pulsed dye laser targets haemoglobin, as in port-wine stains.

Why is "Topical hydroquinone" not the answer?

Hydroquinone cannot remove dermal pigment.

Why is "Carbon dioxide laser ablation of the entire dermis" not the answer?

CO2 ablation would scar.

What concept does this question test?

It tests Procedures: selective photothermolysis in Dermatology. Different wavelengths are needed for different ink colours, and several sessions are required.

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 Procedures: selective photothermolysis?

Learn each condition by its primary lesion, site and signature sign. Then use the flashcards and the other Dermatology 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.