2026 Proffered Presentations
S185: THE FOUR QUADRANT TECHNIQUE: DESCRIPTION OF APPROACH TO SUPRASELLAR TUMORS INVOLVING THE THIRD VENTRICLE AND PEDIATRIC CASE SERIES
Camille K Milton, MD; David G Laird, BS, BA; Emal Lesha, MD; Mallory Saleh, BS; Paul Klimo Jr., MD, MPH; University of Tennessee Health Science Center/ Semmes Murphey Clinic, Department of Neurosurgery
Introduction: Pediatric suprasellar tumors involving the third ventricle pose a neurosurgical challenge due to a location that typically limits gross total resection. Surgical goals for these tumors are 1) maximum safe resection, 2) mitigation of approach related complications, and 3) re-establishment of cerebrospinal fluid pathways. Meticulous perioperative management of endocrine dysfunction is necessary.
Objective: Here we describe the Four Quadrant Technique: a novel approach to the resection of suprasellar tumors with third ventricular involvement and present its associated outcomes in the pediatric population.
Methods: All craniotomies for suprasellar tumors with third ventricular involvement at our tertiary care pediatric hospital from January 2019 to December 2024 were included. All patients were younger than 18. IRB approval was obtained from our institution prior to data collection.
Results: The Four Quadrant Technique is a simple method for approaching the anterior superior (Region 1), posterior superior (Region 2), posterior inferior (Region 3), and anterior inferior (Region 4) quadrants of the third ventricle. All tumors are resected via an anterior interhemispheric transcallosal transforaminal approach. Dilated ventricles and Foramen of Monro may be advantageous to the surgeon in easing access to the tumor. Region 1, with its close association with the fornices, is a “yellow light” area for the surgeon where tumor may be resected subtotally with caution. Regions 2 and 3 are the “green light” areas where the surgeon should aim for maximal resection. Region 4, the anterior inferior quadrant of the third ventricle that is hemisected by a line extending from the clivus, is the “red light” area in which greater restraint should be taken to resection.
34 patients (16M:18F) underwent resection for suprasellar tumors with third ventricular involvement using the anterior interhemispheric transcallosal transforaminal approach and the Four Quadrant Technique. The average patient age was 7.8 years. Tumor types represented included 16 optic nerve gliomas (pilocytic astrocytoma), 16 craniopharyngiomas, 1 ependymoma and 1 ganglioglioma. 7 patients (21%) had history of prior resection. 16 patients (47%) demonstrated preoperative endocrine dysfunction. Tumor resection was subtotal in 29 patients (85%) and gross total in 5 patients (15%). Average length of stay was 6.2 days. 9 patients (26%) had new endocrine dysfunction postoperatively and 4 patients (12%) had new neurological deficit all of which improved over follow-up. 8 patients had direct third ventriculostomies at time of resection, 2 patients had external ventricular drains placed intraoperatively, and 3 patients required postoperative shunt placement. 90-day readmission occurred in 7 patients (21%). Average length of follow-up was 3 years.
Conclusion: The Four Quadrant Technique is a surgical framework for guiding maximum safe resection for suprasellar tumors extending to the third ventricle. Our case series demonstrates the utility of this method in the resection of tumors including pediatric optic nerve gliomas and craniopharyngiomas while minimizing endocrine and cerebrospinal fluid pathway dysfunction.
