Article
Subcortical monopolar language mapping during awake surgery
Subkortikales, monopolares Sprachmapping bei Tumoroperationen unter Wachbedingungen
Search Medline for
Authors
Published: | June 4, 2021 |
---|
Outline
Text
Objective: Intraoperative subcortical language mapping is traditionally performed with bipolar stimulation, which is characterized by frequent interruptions of the operative flow and intermittent mapping of the tumor cavity point by point. To overcome these limitations, we performed a continuous subcortical mapping using a monopolar suction device previously reported for motor tract mapping.
Methods: We present a consecutive case series of 15 patients with glial tumors (4 low grade/ 11 high grade) located in speech eloquent areas, who underwent awake surgery with neuropsychological support. Subcortical monopolar language mapping was performed with the Suction Probe by Raabe et. al. (short train, interstimulus interval 4 msec, pulse duration 500 μsec). Stimulation intensity, evoked temporary speech deficit as well as pre- and postoperative neurological findings were recorded.
Results: Thirteen of 15 procedures were technically successful. Two patients were not cooperative enough for awake surgery. Stimulation intensity ranged from 1 to 10 mA. Intraoperative temporary language errors (a.e. anomia, paraphasia) were evoked in 9 cases (82%) and a temporary total speech arrest in 3 (27%) cases. No seizure occurred during surgery. Gross total resection was achieved in 7 (47%), subtotal resection in 3 (20%) and partial resection in 5 (33%) cases. Postoperative language function deteriorated temporarily in only 2 patients.
Conclusion: Our preliminary data encourage the use of continuous dynamic monopolar language mapping as feasible and safe for localizing speech eloquent fibers adjacent to tumor boundaries.