Regional anaesthesia: sub-Tenon block: practice question

A Anaesthesia 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

Anaesthesia · Regional anaesthesia: sub-Tenon block

Sample item

What is a recognised advantage of a sub-Tenon block over a sharp-needle retrobulbar block for cataract surgery?

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

The answer and the reasoning

B. A blunt cannula reduces the risk of globe perforation and brainstem anaesthesia

The sub-Tenon technique deposits local anaesthetic through a small conjunctival incision using a blunt cannula, avoiding a sharp needle behind the globe. This reduces the risk of globe perforation, retrobulbar haemorrhage and brainstem anaesthesia. Some chemosis and subconjunctival haemorrhage are common.

Option by option

  • A. It gives more motor activity of the eye

    The block aims to reduce eye movement.

  • B. A blunt cannula reduces the risk of globe perforation and brainstem anaesthesia (correct)

    Correct. A blunt cannula is safer than a needle behind the eye.

  • C. It causes proptosis in all cases

    Proptosis does not occur in every case.

  • D. It does not require any local anaesthetic

    Local anaesthetic is required for the block.

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 Anaesthesia questions

Questions about this Anaesthesia question

What is the answer to this Anaesthesia question?

The best answer is B, A blunt cannula reduces the risk of globe perforation and brainstem anaesthesia. The sub-Tenon technique deposits local anaesthetic through a small conjunctival incision using a blunt cannula, avoiding a sharp needle behind the globe.

Why is "It gives more motor activity of the eye" not the answer?

The block aims to reduce eye movement.

Why is "It causes proptosis in all cases" not the answer?

Proptosis does not occur in every case.

Why is "It does not require any local anaesthetic" not the answer?

Local anaesthetic is required for the block.

What concept does this question test?

It tests Regional anaesthesia: sub-Tenon block in Anaesthesia. This reduces the risk of globe perforation, retrobulbar haemorrhage and brainstem anaesthesia. Some chemosis and subconjunctival haemorrhage are common.

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 Regional anaesthesia: sub-Tenon block?

Make a table of each agent, its key advantage and its main side effect. Then use the flashcards and the other Anaesthesia 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.