Mazda Farshad, Jana Felicitas Schader, Alexandra Stauffer, Carl Moritz Zipser, Najmeh Kheram, José Miguel Spirig, Marie-Rosa Fasser, Jonas Widmer, Vincent Hagel
Neurospine 2025;22(2):583-591. Published online June 30, 2025
Objective Endoscopic spine surgery implies possibly severe complications of the central nervous system, from headache to seizures and autonomic dysreflexia. These adverse events might be due to increased intracranial pressure (ICP), presumably induced by increased spinal intra-/epidural pressure caused by fluid irrigation. This study was designed to perform interlaminar endoscopic lumbar discectomy (IELD) at different irrigation fluid settings while monitoring its effect on intra-/epidural and ICPs, with and without dural tears.
Methods Spinal intradural pressures were measured by introducing catheters through a sacral approach to human cadavers’ lumbar, thoracic, and cervical levels. Additionally, an epidural probe was placed at L3–4. ICP was measured by an intraventricular probe. IELD was performed at L3–4, and the effect of varying irrigation pressures by different endoscopic pump systems and gravity-based irrigation on intra-/epidural and ICP pressures was measured before and after durotomy at L3–4.
Results Intradural pressure at L3–4 correlated linearly with increasing irrigation pressure, irrespective of the used pump system (median pressure increase at 100-mmHg irrigation pressure: system I: 7 mmHg, r=0.94, p=0.002; system II: 7 mmHg, r=0.89, p=0.017) or gravity (8 mmHg, r=0.93, p=0.242). This effect was also seen intradurally at the thoracic/cervical spine, epidural, and intracranial level, and was even more pronounced with the maneuver of outflow-occlusion and a dural tear present.
Conclusion While performing IELD, pump pressures correlated linearly to intra-/epidural pressures and ICPs. Pressures did not rise to concerningly high levels without outflow-occlusion, even with increased pump pressures. In the presence of a dural tear, higher pump pressures exacerbated by occlusion may lead to deleterious intradural and ICP elevations.
Citations
Citations to this article as recorded by
Biportal endoscopic foraminotomy of the L7–S1 neuroforamen in dogs: Description of surgical technique and ex vivo comparison with conventional open dorsolateral foraminotomy Dimitrios Bekiaridis, Antonio Pozzi, Frank Steffen, Julian Guevar, Lucas A. Smolders Veterinary Surgery.2026; 55(4): 837. CrossRef
A Protocol to Preserve the Dural Safety Margin During Simultaneous Hybrid Lumbar Unilateral Biportal Endoscopy and Cervical Laminoplasty Karson Tam, H.Y. Li, H.K. Lo, W.L. Kam World Neurosurgery.2026; 209: 124877. CrossRef
Epidemiology of spinal cord hypertension syndrome in water-mediated uniportal full endoscopic thoracolumbar surgery: a single-center experience Haiyang Wu, Luyang Wang, Yiping Zheng, Xizhong Zhu, Wanqi Ren, Ziheng Li, Shoule Ma, Mingwang Zhao, Xingchen Li, Yusheng Xu European Spine Journal.2026;[Epub] CrossRef
Validation of the VIEW score: a novel intraoperative grading scale for visualization in endoscopic spine surgery Vit Kotheeranurak, Surachat Jaroenwareekul, Jin-Sung Kim, Christoph Siepe, Don Young Park, Javier Quillo-Olvera, Worawat Limthongkul, Wicharn Yingsakmongkol, Weerasak Singhatanadgige European Spine Journal.2026;[Epub] CrossRef
Preliminary Report of Full-Endoscopic Spinal Dural Repair Using Double-Arm Sutures With a Biportal Endoscopic System: Technical Note and Feasibility Evaluation in an Ex Vivo Porcine Model Kuo-Hua Chao, Chiu-Ming Chen, Jui-Jung Yang Operative Neurosurgery.2025;[Epub] CrossRef
Objective Endoscopic spine surgery is an emerging technique of minimally invasive spine surgery. However, headache, seizure, and autonomic dysreflexia are possible irrigation-related complications following full-endoscopic lumbar discectomy (FELD). Pressure elevation through fluid irrigation may contribute to these adverse events. A validated experimental model to investigate parameters for guideline definition is lacking. This study aimed to create an experimental setting for FELD with pressure assessments to prove the concept of repeatable and sensitive measurement of intracranial, intra- and epidural pressures during spine endoscopy.
Methods To measure intradural pressure, catheters were introduced through a sacral approach and advanced to lumbar, thoracic, and cervical levels in human cadavers. Similarly, lumbar epidural and intracranial probes were placed. The dural sac was filled with Ringer solution to a physiologic pressure of 15 cmH2O. Lumbar endoscopy was performed on 3 human cadavers at the L3–4 level. Pressure changes were measured continuously at all sites and the effects of backflow-occlusion were monitored.
Results Reproducibility of the experimental model was validated with catheters at the correct locations and stable compartmental pressure baselines at all levels for 3 specimens (mean±standard deviation: 1.3±2.9 mmHg, 9.0±2.0 mmHg, 6.0±1.2 mmHg, respectively). Pressure increase could be detected sensitively by closing the system with backflow-occlusion.
Conclusion An experimental setup for feasible, repeatable, and precise pressure measurement during FELD in a human cadaveric setup has been developed. This allows investigation of the effects of endoscopic techniques and pump pressures on intra-, epidural and intracranial pressure and enables ranges of safe pump pressures per clinical situations.
Citations
Citations to this article as recorded by
A Systematic Review of Complication Management During Uniportal and Biportal Endoscopic Spine Surgery: Dural Tear and Bleeding Siravich Suvithayasiri, Ju Eun Kim, Facundo Van Isseldyk, Marcus Serra, Christopher Martin, Viswanadha Arunkumar, Sotirios Veranis, Prashanth Rao, Enrico Giordan, Piya Chavalparit, Nelson Astur, Samuel Cho, Jin Sung Kim Global Spine Journal.2026;[Epub] CrossRef
Spinal Cord Perfusion Pressure Monitoring after Traumatic Spinal Cord Injury: Indications, Techniques, and Future Horizons Angela Tang-Tan, David J. Caldwell, Alexander A. Aabedi, Maria C. Velasco, Geoffrey T. Manley, Phiroz E. Tarapore, John K. Yue Journal of Neurotrauma.2026;[Epub] CrossRef
Endoscopic resection of lumbar intradural spinal tumors: A case series on feasibility, safety, and preliminary outcomes Facundo Van Isseldyk, Vincent Hagel Brain and Spine.2026; 6: 106040. CrossRef
Full Endoscopic Excision of a Large Intradural Extramedullary Tumor: A Technical Note Kanthila Mahesha, H. Shatananda Prasad Rao Journal of Minimally Invasive Spine Surgery and Technique.2026; 11(1): 124. CrossRef
Fluid and thermal dynamics in endoscopic spine surgery: What surgeons need to know Dong Hun Kim, Sang Don Kim, Jin Young Kim, Jae Taek Hong, Jung Woo Hur Journal of Clinical Neuroscience.2025; 136: 111287. CrossRef
Primer on unilateral biportal endoscopic spine surgery: technical overview for beginners Erick R. Kazarian, Jason I. Yang, Gregory S. Kazarian, Yong H. Kim The Spine Journal.2025;[Epub] CrossRef
Intra-, Epidural And Intracranial Pressure Changes During Interlaminar Endoscopy, With and Without Dural Tear Mazda Farshad, Jana Felicitas Schader, Alexandra Stauffer, Carl Moritz Zipser, Najmeh Kheram, José Miguel Spirig, Marie-Rosa Fasser, Jonas Widmer, Vincent Hagel Neurospine.2025; 22(2): 583. CrossRef
Pioneering Promotion in Endoscopic Spine Surgery: Innovation of Fluid Dynamics and Pressure Measurement Models: Commentary on “An Experimental Model for Fluid Dynamics and Pressures During Endoscopic Lumbar Discectomy” Yi-Hao Liang, Facundo Van Isseldyk Neurospine.2024; 21(3): 753. CrossRef
From the Editor-in-Chief: Featured Articles in the September 2024 Issue Inbo Han Neurospine.2024; 21(3): 743. CrossRef
Endoscopic Transforaminal Thoracic Decompression for Removal of a Giant Calcified Thoracic Disc Herniation Mazda Farshad, Christoph Johannes Laux, Lukas Zingg, Florian Wanivenhaus Neurospine.2024; 21(4): 1116. CrossRef
Full-Endoscopic Resection of a Lumbar Intradural Tumor (Schwannoma): Video Case Report and Description of the Surgical Technique Vincent Hagel, Facundo Van Isseldyk Neurospine.2024; 21(4): 1096. CrossRef