Prolonged central motor conduction time of lower limb muscle in spinocerebellar ataxia 6.
We investigated the function of corticospinal tract in spinocerebellar ataxia 6 (SCA6) by measuring the central motor conduction time (CMCT). Motor evoked potentials (MEP) of tibialis anterior (TA) muscle were elicited by magnetic stimulation to motor cortex and spinal cord in 9 SCA6 patients and 10 normal height- and age-matched subjects. CMCT in lower limb of SCA6 patients (18.1+/-1.9 ms) was significantly prolonged than that of the normal subjects (15.0+/-1.0 ms) ((p < 0.001). The prolonged CMCT was well correlated with the duration of disease (p = 0.005), but MEP amplitudes and stimulation intensities were not significantly different. These results indicate that the corticospinal tract function is also impaired and correlate with the disease duration in SCA6.
Chen
Jen-Tse
JT
Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.
Lin
Yung-Yang
YY
Lee
Yi-Chung
YC
Soong
Bing-Wen
BW
Wu
Zin-An
ZA
Liao
Kwong-Kum
KK
D000328:Adult; D016022:Case-Control Studies; D004558:Electric Stimulation / Q000379:methods; D019054:Evoked Potentials, Motor / Q000502:physiology* / Q000528:radiation effects; D005260:Female; D006801:Humans; D035002:Lower Extremity; D008297:Male; D008592:Menisci, Tibial / Q000503:physiopathology* / Q000528:radiation effects; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D011712:Pyramidal Tracts / Q000503:physiopathology; D011930:Reaction Time / Q000502:physiology / Q000528:radiation effects; D020754:Spinocerebellar Ataxias / Q000473:pathology* / Q000503:physiopathology*; D050781:Transcranial Magnetic Stimulation