Navigated intraoperative ultrasonography for brain tumors: technique, utility and benefits in neuro-oncology

Intraoperative imaging has become one of the most important adjuncts in Neurosurgery especially in surgery of intra-axial tumors. Navigation and intraoperative MR have their limitations. Intraoperative ultrasound has emerged as a versatile and multifaceted tool for this purpose. With advances in technology of the ultrasound scanners and newer multifunctional probes the potential of IOUS is increasingly being utilized in resection of tumors. Addition of image guidance to IOUS has exponentially increased the power of IOUS. Navigated US (nUS) can now overcome many of the limitations of conventional standalone 2DUS. In this pictorial essay, we outline our technique of performing nUS (both 2D and 3D) during resection of intra-axial tumors with illustrated examples highlighting the various steps and benefits of each.