In image-guided neurosurgery, preoperative MRI (pMR) is used for navigation, yet brain deformation during surgery reduces alignment accuracy and can compromise safe tumor resection. This study outlines a workflow to quantify deformation between pMR and intraoperative MRI (iMR) using stereovision-based measurements. Six retrospective neurosurgical cases with pMR, iMR, and intraoperative stereovision were analyzed. Registration was performed through sequential manual, automatic, and fiducial-based alignment, achieving clinically acceptable fiducial registration errors (0.47–0.90 mm). Deformation was then measured around the resection cavity to guide the generation of updated MR images (uMR). Preliminary results confirm that accurate alignment is achievable, supporting the feasibility of using intraoperative stereovision to update MR guidance in real time. Future steps include generating uMR, validating its accuracy compared to iMR, and investigating ultrasound-based strategies for deeper tissue deformation modeling.