A nerve biopsy is a minor surgical procedure used to obtain a sample of a sensory nerve. A nerve biopsy is indicated when symptoms of a possible peripheral nerve problem (neuropathy) are present. The biopsy can differentiate between muscle weakness caused by damage to the nerve fiber (axon) or by disease of the insulating sheath (myelin) that surrounds the nerve. It can also identify inflammation in the blood vessels of the nerves and differentiate between acquired and hereditary forms of neuropathy. Biopsy is usually performed on the most accessible sensory nerve, the sural nerve, located behind the ankle, but other nerves may be selected. By studying biopsied tissue, clinicians can evaluate the extent and distribution of nerve disease.
During the procedure, the skin over the selected nerve site is prepared, and the skin is injected with a local anesthetic. A small incision, about 2.5 inches long, is made in the skin. Then a small section of the nerve ending, about 1 to 2 inches long, is removed.
Most patients experience mild discomfort during the procedure, and some report experiencing pain and a burning sensation when the nerve is cut. The nerve is immediately taken to the laboratory for study. Some patients experience mild chronic pain in the area for as long as 3 months after the biopsy, which occurs when the nerve ending grows. A few patients have experienced permanent loss of sensation in the outside area of the foot.
Please consult with your physician for more information about the benefits, risks, and complications of a nerve biopsy.
