Image-directed tumor resection.

Intra-axial tumors can be localized by intraoperative real-time ultrasound, stereotactic computed tomography (CT), or magnetic resonance imaging (MRI). In the former, intraoperative ultrasound can help a surgeon find a tumor and assess the completeness of resection. Computer interactive CT and MRI-based stereotactic surgery are used to localize the tumor, maintain orientation within the tumor volume, and indicate the CT- and MRI-defined boundaries of the tumor during resection.