We have measured the body surface perception threshold using the quantitative evaluation system for pain (Pain Vision®). This system produced the increasing electrical stimulation (frequency: 50 Hz, pulse width: 0.3 ms) without causing of pain. The concept of pain quantification is to compare the magnitude of the subject's pain to the magnitude of comparative pain-free stimulus to actual pain. The pain degree was calculated from pain evaluating stimulation current and perception threshold. The electrical current perception threshold (CPT) is also available for the evaluation of the peripheral nerve function. The purpose of this study is to determine the standard value of CPT in healthy person as the control CPT range for evaluating the CPT change due to peripheral neuropathy. CPT were measured on the upper limbs (forearm) and the lower limbs (tarsal, and Achilles' tendon) of both of normal group (from 20's to 80's; total number 1658) and diabetes mellitus group (from 40's to 80's; total number 829). As a result in both of male and female of normal group, the average CPT of the lower limbs was 2-3 times higher than that of upper limbs and the average CPT increased by aging. In comparison, the average CPT in 80's was 1.5 times to that of 20's. The average CPT obtained from diabetes mellitus group showed significantly higher levels than normal group. It was considered that the influence of the diabetic neuropathy reflected with the change in CPT. In particular, the changes in upper limb CPT were clearly larger than that of lower limb in every generation. Diabetic neuropathy frequently appears in lower limbs. However, this study suggests that the change in CPT should be focused its attention on the upper limbs.
