Prospective Evaluation of the Need for Fixed Brain Retractors During Complex Cranial Surgery.

[OBJECTIVE] The trend toward minimally invasive surgery has led to a reduction in the size of craniotomies, use of endoscopic assistance to minimize the surgeon's footprint and aid with visualization, and use of alternatives to microsurgery, such as endovascular embolization for aneurysms and radiosurgery for skull base pathologies. A movement away from the use of fixed retractors has also been heralded as an advance in skull base surgery, but the data on the utility of a retractorless approach is small and limited to highly experienced surgeons, often with several decades of experience. This has led some to suggest that retractorless surgery may be unsafe, especially in the hands of young surgeons, in an era where the majority of complex vascular pathology has transitioned to endovascular treatment, and many skull base lesions are treated with chemoradiotherapy adjuncts.

[METHODS] This 19-month study prospectively analyzed the use of retractorless surgery in a consecutive series of 139 lesions in 119 patients with complex intracranial vascular and skull base pathology undergoing craniotomy by a single surgeon.

[RESULTS] The microsurgical approaches included orbitozygomatic craniotomy (40 [28.7%]), supratentorial nonskull base approaches (25 [17.9%]), pterional/minipterional (16 [11.5%]), interhemispheric (12 [8.6%]), suboccipital (11 [7.9%]), and an array of other approaches, such as presigmoid, supracerebellar-infratentorial, far lateral, and retrosigmoid approaches. The most common pathology included aneurysms (47 [33.8%]), skull base tumors (32 [23%]), deep-seated lesions (24 [17.3%]), cavernous malformations (10 [7.2%]), arteriovenous malformations (10 [7.2%]), and arteriovenous fistulae (5 [3.6%]). Of the 139 lesions, 8 (5.75%) cases required the use of a fixed retractor. In total, 94.25% of the cases were successfully treated without a self-retaining retractor system.

[CONCLUSIONS] Retractorless surgery can be performed safely, even by young surgeons, in an era where the majority of complex neurovascular and skull base pathology is treated by endovascular and radiosurgical means. Retractorless surgery can be used in the majority of cases, especially if careful attention is paid to patient positioning, microsurgical dissection of arachnoid planes is carried out to access deep corridors, gravity retraction is used in lieu of fixed retractors, and judicious dynamic retraction with the shafts of instruments replaces the blades of a fixed retractor system.