In diabetic neuropathy, assessment of distal autonomic nerve function is important for the dysfunction of peripheral unmyelinated fibers acts as a factor for development of diabetic foot ulcer and Charcot joints. The sympathetic skin response is known to be an useful electrophysiologic technique to evaluate autonomic funtion in diabetic autonomic neuropathy, but little has been known about the site of excitation and the useful parameters for diagnosis. Our purpose is to find out the proper stimulation site and appropriate electrodiagnostic parameters and diagnostic criteria.

36 patients with history of diabetes mellitus and 16 age and sex matching normal subjects were included and the results of sympathetic skin response were compared. Of the various parameters, onset latency was proven to be the most useful parameters and the proper stimulation site was Median nerve at wrist. There was no correlation between the results of sympathetic skin response and the level of fasting blood glucose, duration of disease, HbA1C, method of treatment or systemic complications. Also there was no correlation between the results of sympathetic skin response and the results of sensory nerve conduction studies.

Our conclusion was that

1) The proper site of stimulation is Median nerve at wrist.

2) The most useful parameter is onset latency.

3) The diagnostic criteria of sympathetic skin response is 1.64sec at ipsilateral palm, 1.57sec at contralateral palm, 2.18sec at ipsilateral sole, 2.17sec at contralateral sole.