Propagation of tonic posturing in supplementary motor area (SMA) seizures.
We analyzed ictal motor symptoms in 10 patients diagnosed to have supplementary motor area (SMA) seizures based on ictal encephalographic (EEG) findings and ictal clinical semiology. Inclusion criteria were (1) EEG seizure pattern in the vertex for the scalp recording or in the area over and/or adjacent to SMA for epicortical recording and (2) ictal motor semiology characterized, as previously reported, by sudden and a brief tonic posturing of extremities and trunk mainly occurring during sleep without loss of consciousness. In 50% (5/10) of the patients, tonic posturing began in one part of the body and moved to other part(s) in 5-10s. Unlike Jacksonian march seen in seizures involving the primary sensorimotor area (S1-M1), it spread in no accordance with the somatotopy in S1-M1. The sequential propagation of tonic posturing may represent the somatotopic organization within the SMA proper.
Ohara
Shinji
S
Human Brain Research Center, Graduate School of Medicine, Kyoto University, Shogoin, Sakyo, Kyoto 606-8507, Japan.
Ikeda
Akio
A
Kunieda
Takeharu
T
Yazawa
Shogo
S
Taki
Junnya
J
Nagamine
Takashi
T
Taki
Waro
W
Miyamoto
Susumu
S
Hashimoto
Nobuo
N
Shibasaki
Hiroshi
H
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D004569:Electroencephalography / Q000379:methods; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology / Q000503:physiopathology*; D010146:Pain / Q000503:physiopathology; D012640:Seizures / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted; D013577:Syndrome; D014742:Videodisc Recording / Q000379:methods