What is a neurodiagnostic skin biopsy?

For Small Fiber Neuropathy which usually causes pain and burning sensations . The skin biopsy is a better alternative to nerve biopsy.

What is a neurodiagnostic skin biopsy?
 

Removing a small piece of skin and looking at it by microscope is a safe and effective way to examine sensory nerve cells
 

Many people have had skin biopsies to remove suspicious skin growths. In the 1990s, it was learned that skin biopsies could also be used to look at the peripheral sensory nerves.^1,2 Nearly all parts of the body have microscopic nerves running through them to allow sensation and movement. Skin biopsies can be processed in a way that allows us to see and count the number of sensory nerve endings, and to look for any neural abnormalities.
 

For many patients being evaluated for painful sensory neuropathies, skin biopsy can replace sural nerve biopsy for gaining information about small sensory axons

Patients suspected of having peripheral nerve disease are evaluated by tests on muscles (electromyography or EMG), or by studying how large nerves conduct signals (nerve conduction studies or NCS). These standard tests are often used for evaluating patients with suspected neuropathy (nerve damage). The types of nerve cells that are damaged in painful sensory neuropathies (small, unmyelinated and thinly myelinated axons) are not well studied by EMG and NCS, and these tests can give false "normal" results in patients with small-fiber neuropathies. In the past, the best way of getting information about sensory neuropathies that cause pain was surgical removal of a part of the sural nerve at the ankle. This left patients with permanent numbness, and caused other complications in some patients.^3–5 Today, skin biopsy, a minor procedure with no serious complications, gives much of the same information. In addition, skin biopsy may even be more sensitive than sural nerve biopsy because it samples the nerves closer to their endings in the skin, where disease usually starts.⁶

References

1. McCarthy BG, Hsieh ST, Stocks A, Hauer P, Macko C, Cornblath DR, Griffin JW, McArthur JC. Cutaneous innervation in sensory neuropathies: evaluation by skin biopsy. Neurology 1995;45:1848–1855.

2. Kennedy WR, Wendelschafer-Crabb G, Johnson T. Quantitation of epidermal nerves in diabetic neuropathy. Neurology 1996;47:1042–1048.

3. Gabriel CM, Howard R, Kinsella N, Lucas S, McColl I, Saldanha G, Hall SM, Hughes RA. Prospective study of the usefulness of sural nerve biopsy. J Neurol Neurosurg Psychiatry 2000;69:442–446.

4. Theriault M, Dort J, Sutherland G, Zochodne DW. A prospective quantitative study of sensory deficits after whole sural nerve biopsies in diabetic and nondiabetic patients. Neurology 1998;50:480–484.

5. Dahlin LB, Eriksson KF, Sundkvist G. Persistent postoperative complaints after whole sural nerve biopsies in diabetic and non-diabetic subjects. Diabet Med 1997;14:353–356.

6. Herrmann DN, Griffin JW, Hauer P, Cornblath DR, McArthur JC. Epidermal nerve fiber density and sural nerve morphometry in peripheral neuropathies. Neurology 1999;53:1634–1640.