Biopsy - Nerve
What is a nerve biopsy?
A nerve biopsy is the removal of a small piece of a nerve for testing in the laboratory. As this will destroy the nerve being analysed, only small sensory nerves close to the surface of the skin are taken for biopsy. The most commonly analysed nerve is the sural nerve, which supplies sensation to the outer edge of the foot.
Why is a nerve biopsy performed?
A nerve biopsy is performed when your doctor suspects atypical nerve inflammation or infiltration and you’ve experienced the following symptoms:-
- numbness and tingling in the feet or hands
- burning, stabbing or shooting pain in affected areas
- loss of balance and co-ordination
- muscle weakness
How to prepare for a nerve biopsy?
You don’t need to do much to prepare for this procedure. Tell your doctor about any medications you are taking. Your doctor should discuss whether you should stop taking them before and during the test.
If you are unable to attend for your biopsy appointment please let the hospital know as soon as possible (you can call the Jefferson ward booking team directly on 0151 529 5488). Failure to attend without proper notice wastes a theatre slot and will result in you being removed from the surgical waiting list. This could result in a significant delay to a diagnosis being made.
What happens during a nerve biopsy?
On the day of biopsy, you will change into a hospital gown and will be taken to an operating room where the procedure is done. The surgeon will locate the nerve. He or she will numb the area with local anaesthetic, a small surgical cut is made and a piece of the nerve is taken. You may feel an electric-shock like sensation when the nerve is cut. The skin is closed with stitches. The nerve sample is sent to a lab for analysis.
Recovering from a nerve biopsy
You will be able to go home following the biopsy. You can eat and drink normally. You will have a dressing and/or bandage over your ankle and you may experience a little pain as the local anaesthetic wears off.
There is no driving restriction after the procedure but we advise that someone else takes you home afterwards just in case there is undue discomfort in the affected limb that could compromise your ability to drive. It will take several days for the wound to heal, during which time, we advise you avoid strenuous activity and elevate the leg as much as you can. Book an appointment with your practice nurse (or local walk-in centre) for suture removal or just a wound check (if dissolvable sutures were used) 10 days after surgery.
Risks of a nerve biopsy
Whilst biopsy of a small sensory nerve is considered to be a safe procedure, there are still risks involved, including bleeding, delayed healing, infection and scarring. There will be permanent loss of sensation (numbness) in the area supplied by the nerve; in the case of sural nerve biopsy (most common nerve biopsied), this involves the lateral ankle at least (C in diagram below). Uncommonly, the area becomes permanently painful due to the permanent nerve damage, although such symptoms usually diminish with time. In the case of (superficial) peroneal nerve biopsy, if underlying peroneus brevis muscle is also biopsied (with your consent), there is a risk of weakening your ability to lift the foot. Sometimes the tissue is not adequate to make a diagnosis, in such cases a repeat procedure may be required.
Risks of sensory loss after biopsy based on 10 and 14 patients who had peroneal (A, B) and sural (C) nerve biopsies respectively. Complications following sural and peroneal nerve biopsies, JNNP 2007; 78: 1271-1272.
After a nerve biopsy
After the biopsy, the nerve sample is sent to a laboratory to be studied under the microscope. It may take a few weeks for the results to be ready. Once the results are back, your doctor may call you or you will come to clinic for a follow up appointment to discuss the findings. They will discuss treatment options with you or further investigations if required.
- Last Updated:01 October 2019
- Review Date:01 November 2023
- Author:Ms Maggie Lee, Dr J Holt, Ms McMahon
A nerve biopsy is the removal of a small piece of a nerve for testing in the laboratory.