UC Berkeley

The skin’s ability to sense its environment is vital to activities of daily living. Cutaneous sensory perception diagnostics allow for the early detection and symptom tracking of tactile dysfunction. However, lack of access to healthcare and the limited frequency of current screening tools can leave skin sensation impairments undiscovered or unmonitored. This work presents a smartphone application for Cutaneous Hand Assessment with a Smartphone Interface (CHASI) to establish Vibrational Perception Thresholds (VPT). CHASI’s vibrational output and force measurement abilities are also characterized. An 18-participant cross-sectional study, with both normative subjects and subjects with sensation impairment, compares the monofilament test with smartphone established VPT (SE- VPT). We find a high positive correlation between SE-VPT and monofilament scores (rs=0.83, p = 0.00014). We also investigate the sensitivity of our proposed SE-VPT method to the motions and forces applied to the touchscreen. We find that variations in force do not alter the practical significance of the monofilament correlation. These results further the smartphone as a potential diagnostic and monitoring tool for hand health.