Stereotactic transcranial magnetic stimulation: correlation with direct electrical cortical stimulation.
OBJECTIVE
To evaluate stereotactic transcranial magnetic stimulation (TMS) as a tool for presurgical functional mapping of human motor cortex.


METHODS
Transcranial magnetic stimulation using a frameless stereotactic system was performed in two patients with tumors near the central sulcus. TMS motor function maps were plotted on the patients' three-dimensional volumetric magnetic resonance imaging data and compared with direct electrical cortical stimulation at surgery with the patient under local anesthesia.


RESULTS
Stereotactic TMS was well tolerated by both patients and was consistent with known somatotopic representation of human motor cortex. The results demonstrated a good correlation between the TMS and electrical cortical stimulation maps, with all TMS responses eliciting more than 75% of the maximum motor evoked potential falling within 1 cm of the electrical cortical stimulation site.


CONCLUSIONS
Our findings indicate that stereotactic TMS is feasible and can provide accurate noninvasive localization of cortical motor function. It may prove to be a useful method for presurgical planning.
Krings
T
T
Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Buchbinder
B R
BR
Butler
W E
WE
Chiappa
K H
KH
Jiang
H J
HJ
Rosen
B R
BR
Cosgrove
G R
GR
D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D010812:Physical Stimulation; D013238:Stereotaxic Techniques / Q000295:instrumentation; D050781:Transcranial Magnetic Stimulation