Morphological measurement of the SEP using a dynamic time warping algorithm.
A dynamic time warping technique was created to align the components of digitally high-pass (300 Hz-2500 Hz) filtered somatosensory evoked potentials evoked by median nerve stimulation recorded with a bipolar cephalic montage. A cost function was assigned related to the amount of warping necessary to match a standard wave derived from 24 normal subjects. Its value ranged from 0.525 to 2.456 (mean 1.305 +/- 0.501). This contrasted with a mean of 5.089 +/- 4.277 (range 0.701-13.972) derived from 25 patients with definite (n = 24) or possible (n = 1) multiple sclerosis chosen on the basis of having few or no clinical abnormalities at the time of testing. Fourteen (56%) of the patients had cost functions that were 3 or more S.D.s above the normal mean as compared to 3 (12%) having prolonged latency of the N19 peak. When used in combination, the cost function and latency yielded 60% abnormalities; 5 times higher than latency measurement alone.
Eisen
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A
Roberts
K
K
Lawrence
P
P
D000328:Adult; D001921:Brain / Q000502:physiology / Q000503:physiopathology; D004569:Electroencephalography / Q000379:methods*; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology