Motor nerve conduction velocity distribution of diabetic neuropathy

Objective To evaluate the motor nerve conduction velocity distribution (MNCVD) properties of early diabetic peripheral neuropathy(DPN).Method Sixty patients with early diabetic peripheral neuropathy were clinically observed and physically examined and their motor and sensory nerve conduction velocity were measured. Using computer-assisted collision technique(CCT),MNCVD for the median,ulnar and peroneal nerves was measured in 10 normal subjects and 60 adult DPN patients. Results Conduction velocity(CV)10%,CV50% and CV90% were (46.7±5.7)m/s,(50.6±5.2)m/s and (53.4±5.0) m/s for the median nerve;(47.4±5.6) m/s,(51.6±5.3) m/s and (55.0±5.4) m/s for the ulnar nerve;and (34.9±5.4) m/s,(39.2±4.6) m/s and (42.7±4.7) m/s for the peroneal nerve. Except for CV10% in median and ulnar nerve,CV50% in all tested nerves,the statistical differences were found in all values between normal and DPN patients. Conclusions MNCVD histogram of DPN patients showed left-shifted velocity peak and reduced conduction velocity in fibers of all the level. The early DPN processes affect peripheral nerves unevenly and the faster-conducting ones were preferentially affected. The MNCVD method is more sensitive and reliable than conventional measures. This technique can be used to diagnose subclinical DPN.