A Methodology For The Early Diagnosis Of Diabetic Autonomic Neuropathy

With the intensify of the world population aging and the improvement of living standards, diabetes has become a common diseases, the incidence of diabetes is increasing year after year. Diabetes is not terrible itself, but various acute and chronic complications, Diabetes neuropathy (DN) is one of the most common syndromes of the diabetic mellitus. Diabetes autonomic neuropathy(DAN) is concerned because the onset of the disease is latent ,early involved and nonreversible pathological changes. DAN threatens cardiovascular system, digestive system, urogenital system, motor nerve of apocrine sweat gland and vision system. Diabetes neuropathy was the 3rd leading cause of death in developed countries after heart attack & vascular diseases and cancer. It is important to control disease and improve patient's living quality; the research on early diagnosis of diabetic autonomic neuropathy has important clinical significances and social values.The diagnosis of DAN is influenced greatly by the complexity and variability of patient's clinical signs, inconsistence detecting methods and diagnosing standard, especially some patients are still not any clinical symptoms. Common method in clinical is often undetected. Sympathetic skin response (SSR) is also called peripheral autonomic surface potential (PASP), it is thought to arise from synchronized activation of palmar or plantar sweat glands, correlate with unmyelinated axon's function. The latency and peak-to-peak amplitude are reliable indicator which reflect periphery sympathetic nervous' activity. SSR proves a reliable, sensitive and non-invasive test of sympathetic function.We discussed the pathogenesis of DAN and described how to examine it in clinic. Based on needs of clinic experiment, we developed an instrument to work on the early diagnosis of DAN; the research consists of two part:1. The mechanics studied the procedure of SSR origin and the affectivness of the electrophysiology indictor of SSR has been studied. Develop an instrument to analyze early DAN based on MSP430. The research emphasized on solving two problems. (1)On account of individual difference, it is difficult to evoke nerve impulse by stimulator. Using all-or-none law of nerve impulse, we control width of activate pulse and using current negative feedback to solve it.(2) Using double T filter and software to eliminate noise and disturb.2 30 controls and 30 DM patients were examined by the instrument to collect electrophysiology data and recorded patients' Neuropad data. We tested the controls' and DM's electrophysiology by Independent-Samples T test, found that latency and peak-to-peak amplitude have high sensitive to the early diagnosis of DAN. We studied the DM's electrophysiology and change color time by correlate, result indicates that latency and peak-to-peak amplitude correlate with severity of diabetes neuropathy.