P.102 Role of interdigital sensory nerve conduction study as a noninvasive approach for early diagnosis of diabetic peripheral neuropathy

Abstract

Background: Diabetes mellitus is a common cause of polyneuropathy. Despite numerous diagnostic tools such as routine electrophysiologic procedures, its early detection is challenging. This study compares a distal electrodiagnostic technique, with conventional approaches to investigate its role in confirming early polyneuropathy. Methods: Thirty-one symptomatic diabetic outpatients and 23 asymptomatic nondiabetic subjects were included in our study. We performed nerve conduction studies on the dorsal sural, medial plantar, and digital branches of the interdigital nerves to toes I, II, and III (as a new antidromic technique). All techniques were applied with the surface stimulator and pick-up electrodes. Results: Only 9 (29%) of patients had impaired routine NCSs. Interestingly, the results of interdigital nerve studies were abnormal in 17 out of 22 patients with normal routine NCSs. Also, 11 and 13 subjects had impaired medial plantar and dorsal sural nerves conduction studies, respectively. According to this method, the prevalence of detectable diabetic neuropathy increased from 46% to 83%. Conclusions: The digital sensory branches can be easily evaluated with the new antidromic SNAP technique for the early diagnosis of diabetic polyneuropathy, especially in presymptomatic and subclinical neuropathies. This method is simple, non-invasive, sensitive, and reproducible. There is no need for needle electrodes or averaging techniques.