Monitoring peripheral neuropathy by the non‐invasive VPT‐60 System

Peripheral neuropathy (PN) can lead to severe, life‐threatening consequences. The non‐invasive methods currently used for PN evaluations are deficient. The purpose of this study was to evaluate an improved, non‐invasive vibration perception threshold (VPT) system for testing peripheral nerve sensitivity. The results from the experimental system were compared for accuracy with Semmes‐Weinstein Monofilaments (SW). The experimental system (VPT‐60 System) was comprised of VPT at 60 Hz, finger skin temperature, weight exerted by finger, sex, & age. A total of 205 subjects were tested. SW and VPT measurements exhibited a polynomial correlation coefficient of 0.92. Statistically significant linear correlations of 0.78 and 0.82 were observed between VPT measurements and SW categories and SW sizes respectively. The VPT‐60 System resulted in an overall 69% accurate assignment of subjects into their correct SW clinical sensitivity category. The VPT‐60 System exhibited 92% sensitivity and 100% specificity. The overall sensitivity of the VPT‐60 System improved from 69% to 88% when subjects' touch sensitivities were categorized as “normal,” “ diminished,” or “loss” of protective sensation. The VPT operating at 60 Hz resulted in an increased accuracy compared to VPT operating at the standard 120 Hz. The VPT‐60 System provided a relatively reliable and accurate method of measuring peripheral nerve sensitivity.