Stereotactic transcranial magnetic stimulation: correlation with direct electrical cortical stimulation

Neurosurgery. 1997 Dec;41(6):1319-25; discussion 1325-6. doi: 10.1097/00006123-199712000-00016.


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.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain Mapping / methods*
  • Electric Stimulation
  • Female
  • Humans
  • Male
  • Motor Cortex / physiology*
  • Physical Stimulation
  • Stereotaxic Techniques* / instrumentation
  • Transcranial Magnetic Stimulation*