Intraoperative localization of the central sulcus by cortical somatosensory evoked potentials in brain tumor. Case report.
Perplexing findings of cortical somatosensory evoked potentials (SEP's) for determining the central sulcus during a craniotomy are reported in a case of brain tumor. On stimulation of the contralateral median nerve in that patient, phase-reversal of SEP waves N1 and P2 was observed not only across the central sulcus but also across the precentral sulcus. In topographic mapping of the N1-P2 amplitude, the sulcus dividing the maximum polarity was the central sulcus; this was confirmed by the cortical stimulation-evoked motor responses. For accurate localization of the central sulcus by cortical SEP's, the distribution of potentials must be analyzed with extensive exposure of the sensorimotor cortex.
Suzuki
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A
Department of Surgical Neurology, Research Institute for Brain and Blood Vessels-Akita, Japan.
Yasui
N
N
D001931:Brain Mapping; D001932:Brain Neoplasms / Q000503:physiopathology* / Q000601:surgery*; D002540:Cerebral Cortex / Q000503:physiopathology*; D003399:Craniotomy; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D016343:Monitoring, Intraoperative