Cortical origin of mini-asterixis in hepatic encephalopathy.
The authors investigated 12 patients with cirrhosis who had hepatic encephalopathy (HE): six with continuous mini-asterixis and six with subclinical HE without asterixis. They studied the coupling between hand-muscle electromyography (EMG) recordings and brain activity recorded by magnetoencephalography. On forearm elevation, patients with tremor developed excessive coupling between activity in the motor cortex (M1) and contralateral hand-muscle EMG recordings at the frequency of mini-asterixis, which was not found in controls. The corticomuscular coupling demonstrates the involvement of M1 in asterixis and may reflect a pathologically slowed and synchronized motor cortical drive.
Timmermann
L
L
Department of Neurology, Heinrich-Heine-University, Düsseldorf, Germany.
Gross
J
J
Kircheis
G
G
Häussinger
D
D
Schnitzler
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020820:Dyskinesias / Q000209:etiology / Q000503:physiopathology*; D004576:Electromyography; D005260:Female; D006501:Hepatic Encephalopathy / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D008103:Liver Cirrhosis / Q000503:physiopathology; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000503:physiopathology