Evoked potentials in a man with a complete large myelinated fibre sensory neuropathy below the neck.
Cortical somatosensory evoked potentials (SEPs) were recorded from a man with a severe neuropathy without touch and proprioception below the neck. Peripheral neurophysiological tests showed a complete large myelinated fibre sensory neuropathy. Sensory threshold to electrical stimulation of the median nerve was 15 mA (normal 2-4 mA). With a stimulus of 39 mA, duration 400 microsecons, applied at the wrist a cortical SEP was recorded with a latency of 84 msec, giving a propagation velocity of 11.9 m/sec. At stimulation rates of above 3.3 Hz the SEP was absent. It is concluded that the SEPs recorded were conducted along A delta peripheral fibres.
Cole
J D
JD
Wessex Neurological Centre, Southampton General Hospital, U.K.
Katifi
H A
HA
D004558:Electric Stimulation; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000502:physiology; D009186:Myelin Sheath / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology*; D010146:Pain / Q000503:physiopathology; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology*; D011930:Reaction Time; D012684:Sensory Thresholds / Q000502:physiology; D013979:Tibial Nerve / Q000502:physiology; D014110:Touch / Q000502:physiology