Left hemibody myoclonus due to anomalous right vertebral artery.
A 43-year-old man presented with sporadic, sudden, brief, and involuntary jerks of his left limbs and trunk muscles. The electromyographic recordings showed short-lasting highly synchronized bursts, compatible with myoclonus limited to the left hemibody. Blink reflex, masseter silent period, cortical and spinal magnetic stimulation, somatosensory cortical evoked potentials, and electroencephalogram (EEG) were normal; the EEG back-averaging showed no spikes preceding the myoclonus. Magnetic resonance imaging and magnetic resonance angiography showed the presence of an anomalous nonectasic right vertebral artery compressing the right side of ventral medulla oblongata. We hypothesize that the aberrant right vertebral artery induced abnormal activation of descending motor tracts responsible for the myoclonus.
Coelho
Miguel
M
Parkinson's Disease and Movement Disorders Unit, Neurology Service, Institut Clinic Malalties del Sistema Nervios, Hospital Clínic Universitari, University of Barcelona, Spain.
Marti
Maria J
MJ
Valls-Solé
Josep
J
Pujol
Teresa
T
Tolosa
Eduardo
E
D000328:Adult; D004558:Electric Stimulation; D004569:Electroencephalography / Q000379:methods; D004576:Electromyography / Q000379:methods; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D007839:Functional Laterality; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008280:Magnetics; D008297:Male; D008526:Medulla Oblongata / Q000473:pathology; D018482:Muscle, Skeletal / Q000503:physiopathology / Q000528:radiation effects; D009207:Myoclonus / Q000473:pathology* / Q000628:therapy; D014711:Vertebral Artery / Q000002:abnormalities* / Q000473:pathology