--is designed to measure the responsivity of the small fibers that subsume the sensations of pain and temperature.

Generally, electrodes are attached to fingers, toes, other parts, and electrical impulses of known temperatures are sent through them. The test relies on patient self-reporting; the patient is supposed to tell whether the electrodes produce sensations of cold, warm, hot and pain. By gradually or rapidly raising or lowering the temperature and listening to the patient reports, the tester can get an idea if those nerve fibers are responding within normal ranges--certain rapid temperature raisings or lowerings, for example, should produce a sensation of pain if fibers are responding normally.

See:

http://peripheralneuropathycenter.uc...nt/index.shtml

http://mcgs.bcbsfl.com/?doc=Quantita...sory%20Testing

http://www.neurology.org/content/60/6/898.full


Unfortunately, as the second link points out, a lot of insurances consider the procedure experimental and are unwilling to pay for it.