A nerve biopsy is the removal of a small piece of a nerve for examination.
Biopsy - nerve
How the Test is Performed
A nerve biopsy is most often done on a nerve in the ankle, forearm, or along a rib.
The health care provider applies medicine to numb the area before the procedure. The doctor makes a small surgical cut and removes a piece of the nerve. The cut is then closed and a bandage put on it. The nerve sample is sent to a lab, where it is examined under a microscope.
How to Prepare for the Test
There is no special preparation.
How the Test will Feel
When the numbing medicine (local anesthetic) is injected, you will feel a prick and a mild sting. The biopsy site may be sore for a few days after the test.
Why the Test is Performed
Nerve biopsy may be done to help diagnose:
- Axon degeneration (destruction of the axon portion of the nerve cell)
- Damage to the small nerves
- Demyelination (destruction of parts of the myelin sheath covering the nerve)
- Inflammatory nerve conditions (neuropathies)
Conditions for which the test may be done include any of the following:
- Alcoholic neuropathy
- Axillary nerve dysfunction
- Brachial plexopathy
- Charcot-Marie-Tooth disease (hereditary)
- Common peroneal nerve dysfunction
- Distal median nerve dysfunction
- Mononeuritis multiplex
- Necrotizing vasculitis
- Radial nerve dysfunction
- Tibial nerve dysfunction
A normal result means the nerve appears normal.
What Abnormal Results Mean
Abnormal results may be due to:
- Amyloidosis (sural nerve biopsy is most often used)
- Inflammation of the nerve
- Loss of axon tissue
- Metabolic neuropathies
- Necrotizing vasculitis
- Allergic reaction to the local anesthetic
- Discomfort after the procedure
- Infection (a slight risk any time the skin is broken)
- Permanent nerve damage (uncommon; minimized by careful site selection)
Nerve biopsy is invasive and is useful only in certain situations. Talk to your provider about your options.
Shy ME. Peripheral neuropathies. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 420.
Weis J, Brandner S, Lammens M, Sommer C, Vallat JM. Processing of nerve biopsies: a practical guide for neuropathologists. Clin Neuropathol. 2012;31:7-23. PMID: 22192700 www.ncbi.nlm.nih.gov/pubmed/22192700.
Reviewed By: Daniel Kantor, MD, Kantor Neurology, Coconut Creek, FL and Immediate Past President of the Florida Society of Neurology (FSN), Gainesville, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.