Nerve conduction study, electromyography and somatosensory evoked potentials in non-Friedreich early onset cerebellar ataxia. A comparative study with Friedreich's ataxia and late onset cerebellar ataxia.
Electrophysiological findings in 14 patients with non-Friedreich early onset cerebellar ataxia are reported. Nerve conduction studies showed reduction of sensory action potential amplitudes in 7 cases associated in 3 with a decrease of sensory conduction velocities. Six subjects also exhibited a chronic neurogenic pattern to standard needle electromyography. Motor conduction velocities were normal in all cases; only two cases showed an increase in distal motor latencies. Short-latency somatosensory evoked potentials following median nerve stimulation revealed a prolonged central conduction time (N13-N20 interpeak latency) in 7 cases, compatible with supraspinal damage of the somatosensory pathways. These electrophysiological data are compared with those obtained in two reference groups of patients, respectively affected by Friedreich's ataxia and olivo-ponto-cerebellar atrophy.
Mondelli
M
M
Institute of Neurological Sciences, University of Siena, Italy.
Decchi
B
B
Parlanti
S
S
Scarpini
C
C
Rossi
A
A
D000200:Action Potentials / Q000502:physiology; D000293:Adolescent; D000328:Adult; D002524:Cerebellar Ataxia / Q000503:physiopathology*; D002648:Child; D004576:Electromyography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D005621:Friedreich Ataxia / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009431:Neural Conduction / Q000502:physiology*; D013997:Time Factors