Visualization of Brain Shift Corrected Functional Magnetic Resonance Imaging Data for Intraoperative Brain Mapping

Area of Science:

• Neurosurgery
• Medical Imaging
• Computational Neuroscience

Background:

• Brain tumor surgery necessitates balancing maximal tumor removal with preserving eloquent cortex.
• Awake craniotomy with direct cortical stimulation (DCS) aids surgical decision-making by mapping brain function.
• Preoperative functional MRI (fMRI) planning is limited by intraoperative brain shift.

Purpose of the Study:

• To develop an integrated visualization method for fMRI and DCS results that is intuitive for surgeons.
• To address the limitations of preoperative fMRI due to brain shift during surgery.

Main Methods:

• Constructed an image registration pipeline to overlay brain-shifted fMRI data onto the exposed cortical surface.
• Registered preoperative fMRI and DCS data, calculating residual errors for various misalignments.
• Validated the pipeline on data from five brain tumor patients undergoing awake craniotomy.

Main Results:

• Registration errors were below 5 mm for translations up to 25 mm and rotations up to 10-15°.
• Achieved a 95% success rate with a 5 mm error tolerance for rotational misalignments up to 20°.
• Demonstrated good quality registrations across all five patient cases.

Conclusions:

• A proof-of-concept image registration pipeline offers acceptable accuracy for intraoperative use.
• The pipeline provides multimodality visualization, potentially enhancing intraoperative brain mapping.
• This integrated approach may improve surgical outcomes in brain tumor resections.