[Idiopathic rabbit syndrome: a case report].
We report a patient with idiopathic oromandibular tremor resembling rabbit syndrome. The patient is a 36-year-old Japanese woman without any past and medical histories. On neurological examination, there was no abnormal finding except the oromandibular tremor. The tremor was confined to the jaw and perioral muscles. There was no extremity tremor. Laboratory findings were all normal, as well as her MRI and EEG. Surface EMG studies revealed that regular grouped discharges at a frequency of about 6 Hz appeared in the masseter, the orbicularis oris, and the digastric, and that the alternative contractions were found between the masseter and the digastric. Oral administration of tiapride was effective, but diazepam, trihexyphenydil, levodopa, and a beta-blocker were without effect. Although she had not taken neuroleptics, the appearance of the tremor was identical to the rabbit syndrome. The efficacy of the dopamine blockade may suggest that an abnormal basal ganglia function contributes to the pathophysiologic mechanism underlying this type of tremor.
Miwa
H
H
Department of Neurology, Juntendo University Urayasu Hospital, Chiba, Japan.
Sasaki
Y
Y
Hatori
K
K
Tanaka
S
S
Mizuno
Y
Y
D000328:Adult; D001480:Basal Ganglia Diseases / Q000175:diagnosis* / Q000503:physiopathology; D003937:Diagnosis, Differential; D004409:Dyskinesia, Drug-Induced / Q000175:diagnosis* / Q000503:physiopathology; D004576:Electromyography; D005260:Female; D006801:Humans; D008336:Mandibular Diseases / Q000175:diagnosis* / Q000503:physiopathology; D014202:Tremor / Q000175:diagnosis* / Q000503:physiopathology