Intraoperative image updating for brain shift following dural opening

Area of Science:

• Neurosurgery
• Medical Imaging
• Computational Anatomy

Background:

• Preoperative MRI (pMR) coregistration for intraoperative navigation is often inaccurate due to brain deformation (brain shift).
• Brain shift occurs after dural opening, significantly compromising the precision of standard neurosurgical navigation systems.

Purpose of the Study:

• To develop and evaluate an updated MRI (uMR) generation process in the operating room (OR) to correct for intraoperative brain deformation.
• To assess the accuracy and computational efficiency of the uMR technique compared to standard pMR coregistration.

Main Methods:

• Acquired intraoperative stereovision (iSV) images to create a 3D cortical surface model.
• Registered iSV surface with pMR to detect displacements, assimilated by a biomechanical model to estimate nonrigid brain deformation.
• Generated uMR in the OR and calculated Target Registration Errors (TREs) against iSV-derived surface positions.

Main Results:

• uMR views showed improved visual alignment and accuracy compared to pMR, with less misalignment.
• Average TRE for uMR was 1.60 ± 0.43 mm, significantly better than pMR's 7.31 ± 2.82 mm.
• The uMR generation process took 7-8 minutes, with minimal disruption to surgical workflow.

Conclusions:

• Computational model-based assimilation of iSV cortical displacements effectively compensates for brain deformation during surgery.
• The uMR technique offers superior accuracy over pMR for intraoperative navigation, as evidenced by lower model-data misfit and TRE.
• The uMR approach is computationally efficient and clinically feasible, enhancing neurosurgical navigation accuracy.