MAGNETIC MOTOR EVOKED POTENTIALS IN PARKINSONISM

Abstract

SUMMARY Transcranial magnetic stimulation of the motor cortex may provide useful data on the functional state of motor output of the central motor structures and on the functional condition of the intracerebral motor network. They can illustrate subtle pathophysiological disturbance's in diseases where there is no direct involvement of central motor pathways such as parkinson's disease. The aim of the study was: 1- To study the effect of different types of parkinsonism and antiparkinsonian drugs on motor evoked potentials using magnetic stimulation. 2- To correlate the changes in motor evoked potentials to degree of disability and clinical presentation. The present study included 31 parkinsonian patients ( 19 males and 12 females) who came to outpatient clinic of neurology department in Assiut university Hospital during the period from June, 1998 to June, 1999. Twenty two patients were under irregular treatment of levodopa-carbidopa or anticholinergics and have withdrawn their medications for at least one month duration. The remaining 9 were not previously treated. The patients were classified according to Lees diagnostic criteria of parkinson's disease (1988), into two groups 15 PD patients and 16 Non-PD patients (other etiologies). The severity of the disease was evaluated clinically, "on" and "off' therapy, by Webster scale (1968).