The Intraoperative Golden Hour in Minimally Invasive Parafascicular Surgery for Brain Tumors

Minimally invasive parafascicular surgery (MIPS) represents a paradigm shift in the management of deep-seated brain tumors, enabling function-sparing resections previously limited to biopsy and/or medical therapy. Central to MIPS are structured frameworks guiding preoperative planning and intraoperative execution. The six-pillar concept-comprising imaging, navigation, atraumatic access, optics, resection, and postoperative care-provides a comprehensive approach to integrate advanced neuroimaging, tractography, tubular retractor systems, fluorescence-guided resection, and neuromonitoring to optimize functional outcomes. Five-point target-trajectory complex planning-craniotomy, outer radial corridor, inner radial corridor, target, and resection margins-translates preoperative imaging and functional mapping into a precise surgical trajectory, balancing maximal tumor resection with minimal disruption of eloquent brain structures. Preoperative assessment of tumor characteristics, vascular relationships, and cortical eloquence informs trajectory planning and intraoperative adjustments. A critical determinant of MIPS success is the intraoperative golden hour, referring to the high-risk period surrounding brain cannulation with a tubular retractor. Key principles include (1) precannulation system checks to ensure instrument readiness; (2) access injury prevention through optimized craniotomy sizing and sulcal preparation; (3) tubular-tumor targeting accuracy addressing brain and tubular translation, tumor displacement, and white-matter sleeves; and (4) intracranial pressure control strategies to minimize tissue strain and venous congestion. Overcoming this period enables a controlled resection phase guided by the above-mentioned surgical adjuncts. The six-pillar concept and five-point target-trajectory complex planning are the foundations of MIPS planning, whereas the intraoperative golden hour provides a roadmap for successful intraoperative delivery of the surgical plan.