A nerve biopsy is the removal of a small piece of a nerve for examination.
Biopsy - nerve
A nerve biopsy is most often done on a nerve in the ankle, forearm, or along a rib.
The health care provider will apply medicine to numb the area before the procedure. The doctor makes a small surgical cut and removes a piece of the nerve. The nerve sample is sent to a lab, where it is examined under a microscope.
There is no special preparation.
When the numbing medicine (local anesthetic) is injected, you will feel a prick and a mild sting. The biopsy site will be sore for a few days after the test.
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)
Additional conditions under which the test may be performed:
- 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.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
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 doctor about your options.
Shy ME. Peripheral neuropathies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier. 2007: chap 446.
Vallat, JM, Funalot, B, and Magy, L. Nerve biopsy: requirements for diagnosis and clinical value. Acta Neuropathol 2011, 121: 313-326.
Reviewed By: Luc Jasmin, MD, PhD, FRCS (C), FACS, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles CA; Department of Surgery at Los Robles Hospital, Thousand Oaks CA; Department of Surgery at Ashland Community Hospital, Ashland OR; Department of Surgery at Cheyenne Regional Medical Center, Cheyenne WY; Department of Anatomy at UCSF, San Francisco CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.