After the Knife: A Detailed Roadmap for Vestibular Schwannoma Resection in the Semi-Sitting Position - How I do it.

BACKGROUND: Vestibular schwannoma surgery remains a neurosurgical challenge, with known risks, dependent on a number of factors, from patient selection to surgical experience of the team. The semi-sitting position has gained popularity as an alternative to the traditional supine position for vestibular schwannoma resection due to potential advantages such as improved surgical exposure due to clearer surgical field and anatomical orientation. However, there is a lack of standardized protocols for performing the procedure in the semi-sitting position, leading to variations in surgical techniques and outcomes. METHODS: In this study, we aimed to establish a standardized approach for vestibular schwannoma resection using the semi-sitting position. Initiating after final position for semi-sitting, the authors have divided the surgical steps into five major parts for improved understanding and replication. Surgical techniques were analyzed through one hundred steps to identify commonalities, determining the optimal procedural steps for the semi-sitting position using surgical video for visual conceptualization. RESULTS: The analysis described one hundred steps for vestibular schwannoma resection in the semi-sitting position, with visual demonstration of the various parts of the procedure through surgical videos. Specific recommendations for each step were outlined, including appropriate approach, monitoring strategies, and tumor and posterior fossa structures manipulation. Five major parts of the procedure were identified, leading to a reproducible standardization of the surgical procedure of vestibular schwannoma resection in the semi-sitting position. CONCLUSIONS: This study provides a comprehensive standardized protocol for the semi-sitting procedure in vestibular schwannoma resection. By establishing a consistent approach, surgeons can minimize variations in surgical techniques and improve patient outcomes. The identified steps and recommendations can serve as a valuable resource for surgical teams involved in vestibular schwannoma resection and facilitate the dissemination and reproducibility of best practices.

Two-Stage Resection of a Giant Trigeminal Schwannoma in a Non-Neurofibromatosis Type 2 Pediatric Patient: A Case Report, Systematic Review, and Intraoperative Video.

BACKGROUND: Trigeminal schwannoma is an uncommon tumor in pediatric patients. Several surgical approaches have been described in the literature. METHODS: The case of an 11-year-old boy with a giant dumbbell-shaped trigeminal schwannoma removed through a 2-stage approach was presented with an intraoperative video. Using PubMed and Scopus, the literature on trigeminal schwannoma in pediatric patients was searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. RESULTS: The search strategy yielded 312 titles, of which 13 were included in the review. Cases of trigeminal schwannoma were described, with a highly variable clinical presentation and anatomical arrangement in cranial fossae. Two-stage approaches were reported, although most studies described single-stage approaches. Common postoperative outcomes were a range of disturbances of cranial nerve V. CONCLUSIONS: The surgical approach varies based on the tumor conformation. However, a 2-stage pterional subtemporal and semisitting retrosigmoid approach is a safe, practical, and effective strategy for the removal of dumbbell-shaped trigeminal schwannoma in a pediatric patient.

Multiple Cranial Dural and Pial Arteriovenous Fistulas with Occlusion of All After Embolization of Primary Superior Sagittal Sinus Dural Fistula.

BACKGROUND: We present a rare case of multiple intracranial arteriovenous fistulas (AVFs). A young female presented with headache and a left eyelid pulsatile swelling. CASE DESCRIPTION: Magnetic resonance imaging demonstrated numerous dilated cortical veins, along with a prominent left superior ophthalmic vein. A diagnostic cerebral angiogram revealed 5 distinct AVFs including 4 dural AVFs (dAVFs) and a pial AVF (pAVF). The largest dAVF was at the superior sagittal sinus. The others included bilateral ethmoidal, torcular, and a pAVF arising of the right pericallosal artery. She was treated by endovascular transarterial Onyx embolization. Only the superior sagittal sinus fistula was treated via middle meningeal artery feeders with complete occlusion. Immediate follow-up angiogram also showed complete spontaneous occlusion of the untreated dAVFs and pial AVF. CONCLUSIONS: This case is exceedingly unique considering the multiplicity of AVFs, concurrent presence of pial and dural AVF, and spontaneous occlusion of all untreated AVFs after embolizing the largest shunting fistula.

Rescue Maneuver for Dislocated Woven EndoBridge Device in Middle Cerebral Artery.

BACKGROUND: Intrasaccular flow disruption has emerged as a useful modality for treatment of wide-necked saccular aneurysm at vessel bifurcations. The Woven EndoBridge (WEB) device is one such device that has been evaluated in several series with excellent safety and good midterm efficacy. Bailout techniques to retrieve or reposition a dislocated WEB device are sparse and associated with significant risks. We describe a case of a dislocated WEB device that was repositioned with a microcatheter alone. METHODS: We describe a case of a WEB device that inadvertently detached in the parent vessel and the technique we used to reposition it. A number of bailout techniques are discussed with pros and cons associated with each maneuver. RESULTS: An unruptured middle cerebral artery (MCA) aneurysm was treated by endovascular embolization with a WEB device. The WEB was deployed within the aneurysm without incident. However, the device failed to detach. While attempting to resheath the device, it extruded out of the aneurysm and then inadvertently detached in the MCA. After many options were considered, a microcatheter alone was used to push the device back into the aneurysm. CONCLUSION: Caution should be exercised, especially when detaching the WEB device. Microcatheter repositioning by pushing the dislocated device may be attempted, especially if part of the device is within the aneurysm. This is the first description of the described microcatheter repositioning rescue maneuver.