A Novel Language Paradigm for Intraoperative Language Mapping: Feasibility and Evaluation

Area of Science:

• Neuroscience
• Neurosurgery
• Cognitive Science

Background:

• Mapping language functions during awake craniotomy is challenging due to time constraints for direct cortical stimulation (DCS).
• Existing paradigms often exceed the 4-second limit required for DCS, increasing intraoperative risks.
• A novel, time-efficient language paradigm is needed to accurately assess critical language areas.

Purpose of the Study:

• To develop and evaluate a novel intraoperative language paradigm for direct cortical stimulation (DCS).
• To assess the paradigm's ability to map language functions within the 4-second DCS time limit.
• To determine the paradigm's feasibility and impact on neuropsychological outcomes in brain tumor patients.

Main Methods:

• Designed a language task combining picture naming and verb generation, executable within 4 seconds.
• Validated the paradigm's ability to map the cortical language network using functional magnetic resonance imaging (fMRI) in healthy subjects.
• Assessed the paradigm's feasibility and clinical utility in brain tumor patients undergoing awake craniotomy, monitoring neuropsychological status pre- and post-surgery.

Main Results:

• fMRI demonstrated activation within the language network around the sylvian fissure in healthy subjects.
• The language task trials were consistently completed within the 4-second limit.
• All intraoperative patients exhibited DCS-induced language errors during the task, indicating effective stimulation.
• Postoperative assessments revealed mild, transient neuropsychological impairments compared to presurgical baselines.

Conclusions:

• The novel language paradigm effectively and safely engages critical language functions during intraoperative DCS.
• This paradigm allows for precise mapping of language areas, crucial for minimizing surgical risks.
• Its use can lead to better preservation of cognitive functions and reduced postoperative neuropsychological deficits.