MOTOR IMPAIRMENT IN WILSONS-DISEASE .3. THE CLINICAL IMPACT OF PYRAMIDAL TRACT INVOLVEMENT

Magnetic brain stimulation was performed on 24 patients with Wilson's disease (WD). Responses to the right and left first dorsal interosseus muscle (FDI) and to the right and left tibialis anterior muscle (TA) were analysed. In 45% of the patients prolonged central motor conducti on times (CCTs) to the FDIs were found, whereas only 12% of the patien ts presented with prolonged CCTs to the TA muscles. No consistent sign ificant correlations between copper metabolism and pyramidal tract fun ction tested by magnetic brain stimulation were found. An improvement of CCTs and response amplitudes with copper elimination therapy was ob served only at early phases of therapy. There was no correlation with duration of therapy or neurological symptoms. Thus magnetic brain stim ulation turns out to be sensitive to detect subclinical pyramidal trac t impairment in WD but seems to test a too specific aspect of motor im pairment in WD to reflect the overall neurological status of the patie nts. Therefore, it has to be combined with other tests to be used for therapy control.