Spontaneous intracranial hypotension (SIH) is most commonly caused by spinal CSF leaks, with ventral dural defects frequently requiring surgical repair when conservative measures fail. Endoscopic transforaminal approaches have emerged as minimally invasive alternatives to traditional open techniques, but the physiological consequences of continuous irrigation in the presence of a dural defect remain poorly understood. The authors report the case of a 36-year-old woman with recurrent SIH due to a persistent ventral T11-12 CSF leak despite prior laminectomy, revision repair, and multiple targeted interventions. She underwent transforaminal endoscopic discectomy and ventral dural repair. During the procedure, under continuous gravity-assisted irrigation, she developed sudden, severe, and reproducible hypertension with her systolic blood pressure reaching 275 mm Hg, refractory to anesthetic deepening and multiple antihypertensive agents. Irrigation cessation resulted in immediate hemodynamic normalization, while irrigation reintroduction led to recurrence of the hypertensive response. The procedure was completed after minimizing irrigation, and the patient stabilized postoperatively without further hemodynamic instability. The authors propose that this phenomenon reflects direct transmission of irrigation-induced epidural pressure into the intrathecal space through the persistent dural defect, resulting in acute intracranial pressure elevation and sympathetic activation. In contrast to standard endoscopic cases, chronic CSF leak states may create a compartmentalized and fibrotic epidural environment with reduced compliance and impaired outflow, predisposing the epidural space/operative field to rapid pressure accumulation even under low-pressure irrigation systems. This case highlights a previously underrecognized mechanism of intraoperative hemodynamic instability during endoscopic spine surgery and underscores the importance of considering altered pressure dynamics in patients with CSF leaks. Surgeons should maintain a high index of suspicion for irrigation-related complications in this population and consider strategies to minimize inflow pressure, optimize outflow, and promptly interrupt irrigation in the setting of unexplained physiological changes. These findings have important implications for surgical planning, intraoperative management, and the safe expansion of endoscopic techniques in CSF leak repair.

In conventional biportal endoscopic spine surgery, active surgical manipulation is primarily performed through the working portal using the dominant hand, while the endoscopic viewing portal serves a passive role limited to visualization. Although the biportal approach provides superior optical advantages, the functional potential of the endoscopic viewing portal remains underused. The aim of this technical note was to describe a bimanual technique using an endoscopic self-retractor mounted on the endoscopic trocar to expand the operative role of the endoscopic viewing portal. The nondominant hand actively controls the endoscopic self-retractor through finger-based manipulation, while the dominant hand performs surgical maneuvers through the working portal, enabling two-handed manipulation. This technique allows surgeon-controlled retraction, dissection, and tissue protection and can be applied to a wide range of operative situations, including soft tissue dissection, ligamentum flavum resection, dural and nerve root protection, epidural lesion removal, and hemostasis. The bimanual technique with an endoscopic self-retractor was used in 396 cases (33 cervical, 8 thoracic, and 355 lumbar). It was applied in various procedures such as foraminotomy, discectomy, laminectomy, and fusion. No endoscopic self-retractor-related complications or adverse events were observed. By transforming the endoscopic viewing portal into an active auxiliary operative channel, the bimanual technique enhances surgical precision, safety, ergonomics, and autonomy in biportal endoscopic spine surgery.