Enhancement and Dynamic Time Warping of Somatosensory Evoked Potential Components Applied to Patients with Multiple Sclerosis

A zero-phase, high-pass digital filter at 300 Hz was used to emphasize the higher frequency, smaller peaks of the somatosensory evoked potential (SEP). Using the digital filter, a consistent pattern of peaks was observed in normals. A dynamic time-warping technique was created to align the peaks of digitally high-pass filtered SEP´s. Based on this technique, a clinical test for abnormality of the SEP was developed and applied to 25 multiple sclerosis patients. The results showed that three times as many multiple sclerosis SEP´s were identified by the dynamic time warping as by the traditional latency measurement.