Microscope Integration and Heads-Up Display in Brain Surgery

Recent advances in frameless stereotaxis, microscope integration, image segmentation, three-dimensional reconstruction, heads-up display (HUD), and intraoperative surgical navigation systems such as Navigation Update show promise in improving the quality of neurosurgical interventions, particularly microscope-based brain surgery. Surgeons now have the ability to apply detailed patient-specific information about critical normal and pathologic structure and their anatomic relationships directly into the operative field. These technologies can link the visual focal point of the operating microscope to an overlaid three-dimensional reconstruction of the most relevant structures. The information that is projected into the eyepieces and overlaid on the optical display is updated in real time as the surgeon moves the microscope or adjusts the focal point depth, without the need to divert attention from the operative field to a computer screen or to introduce navigated instruments. Furthermore, the very recent introduction of the intraoperative Navigation Update system allows the operator to reregister the stereotaxic field to match intraoperative anatomic landmarks in less than 2 minutes, without the need for intraoperative CT, MRI, or ultrasonography. This advance has the potential to significantly increase the utility of surgical navigation and addresses one of the most persistent and difficult challenges in this field, that of intraoperative brain shift. Together these evolving technologies have the potential to transform the operative experience for brain surgeons. This chapter describes how current integrated augmented reality platforms work and includes a proposed workflow for augmented reality implementation, case-based examples of successful implementation, and areas where further development is needed. Readers will be able to apply the ideas presented to their practice in surgical planning and intraoperative applications and to understand the limitations of the technology.