Rayan, Tarek

Abstract Objective Cerebrovascular complications (CVC) are rare consequences of vestibular schwannoma (VS) surgery. Our objective was to assess incidences of findings suggestive of postoperative CVC in a large single surgeon cohort, as well as potential risk factors, and implications. Study Design A cohort of 591 patients was retrospectively reviewed. Postoperative magnetic resonance images were screened for findings suggestive of stroke, T2 hyperintensity in the cerebellopontine angle structures or new encephalomalacia. Clinical records were queried for findings consistent with postoperative CVC. Results In total, 61 patients had radiographic findings consistent with possible postoperative CVC (10%); of them, eight had documented intraoperative vascular injury (1.4%), and four had postoperative clinical exam changes indicative of CVC (0.7%). Clinically manifest intraoperative vascular injuries occurred in four patients and involved the petrosal venous complex (n = 3, 5%) or anterior inferior cerebellar artery (n = 1, 2%); clinical deficits included hemiparesis (n = 1, 2%), facial anesthesia (n = 2, 4%), dysphagia (n = 2, 2%), and unfavorable facial nerve function in two (50%). Three out of four patients in this group required out-of-home placement (75%). Clinical CVCs (n = 4) were not significantly associated with tumor size, tumor cyst, gross total resection, or length of stay. Patients with clinical CVC were significantly more likely to require posthospitalization rehabilitation (19 vs. 75%, p = 0.02; 14 vs. 100%, p = 0.0002). Conclusion Although radiographic findings suggestive of CVC were unexpectedly common in this cohort, intraoperative vascular injury and postoperative clinical CVC were exceedingly rare. The association between unfavorable facial nerve outcome and clinical CVC is likely a marker for more difficult operations, predisposing to higher risk of complications.

Abstract Please see the full-text version of this guideline (https://www.cns.org/guidelines/guidelines-management-patients-vestibular-schwannoma/chapter_8) for the target population of each recommendation listed below. QUESTION 1 What surgical approaches for vestibular schwannomas (VS) are best for complete resection and facial nerve (FN) preservation when serviceable hearing is present? RECOMMENDATION There is insufficient evidence to support the superiority of either the middle fossa (MF) or the retrosigmoid (RS) approach for complete VS resection and FN preservation when serviceable hearing is present. QUESTION 2 Which surgical approach (RS or translabyrinthine [TL]) for VS is best for complete resection and FN preservation when serviceable hearing is not present? RECOMMENDATION There is insufficient evidence to support the superiority of either the RS or the TL approach for complete VS resection and FN preservation when serviceable hearing is not present. QUESTION 3 Does VS size matter for facial and vestibulocochlear nerve preservation with surgical resection? RECOMMENDATION Level 3: Patients with larger VS tumor size should be counseled about the greater than average risk of loss of serviceable hearing. QUESTION 4 Should small intracanalicular tumors (<1.5 cm) be surgically resected? RECOMMENDATION There are insufficient data to support a firm recommendation that surgery be the primary treatment for this subclass of VSs. QUESTION 5 Is hearing preservation routinely possible with VS surgical resection when serviceable hearing is present? RECOMMENDATION Level 3: Hearing preservation surgery via the MF or the RS approach may be attempted in patients with small tumor size (<1.5 cm) and good preoperative hearing. QUESTION 6 When should surgical resection be the initial treatment in patients with neurofibromatosis type 2 (NF2)? RECOMMENDATION There is insufficient evidence that surgical resection should be the initial treatment in patients with NF2. QUESTION 7 Does a multidisciplinary team, consisting of neurosurgery and neurotology, provides the best outcomes of complete resection and facial/vestibulocochlear nerve preservation for patients undergoing resection of VSs? RECOMMENDATION There is insufficient evidence to support stating that a multidisciplinary team, usually consisting of a neurosurgeon and a neurotologist, provides superior outcomes compared to either subspecialist working alone. QUESTION 8 Does a subtotal surgical resection of a VS followed by stereotactic radiosurgery (SRS) to the residual tumor provide comparable hearing and FN preservation to patients who undergo a complete surgical resection? RECOMMENDATION There is insufficient evidence to support subtotal resection (STR) followed by SRS provides comparable hearing and FN preservation to patients who undergo a complete surgical resection. QUESTION 9 Does surgical resection of VS treat preoperative balance problems more effectively than SRS? RECOMMENDATION There is insufficient evidence to support either surgical resection or SRS for treatment of preoperative balance problems. QUESTION 10 Does surgical resection of VS treat preoperative trigeminal neuralgia more effectively than SRS? RECOMMENDATION Level 3: Surgical resection of VSs may be used to better relieve symptoms of trigeminal neuralgia than SRS. QUESTION 11 Is surgical resection of VSs more difficult (associated with higher facial neuropathies and STR rates) after initial treatment with SRS? RECOMMENDATION Level 3: If microsurgical resection is necessary after SRS, it is recommended that patients be counseled that there is an increased likelihood of a STR and decreased FN function. The full guideline can be found at: https://www.cns.org/guidelines/guidelines-management-patients-vestibular-schwannoma/chapter_8.

Abstract Dr Albert L. Rhoton Jr became the focal point of neurosurgery's evolution in understanding the intricate and complex microanatomy of the human brain over the last 4 decades. His pioneering work on cadaveric specimens proved to be a pivotal endeavor in the pursuit to better understand the complex microsurgical anatomy of cranial surgery. This paper details his early career at the Mayo Clinic in Rochester, Minnesota. A comprehensive review and synthesis of data acquired from the institutional historical archives including the Annual Reports to the Executive Committee, the Reports to the Board of Directors, the MAYOVOX Newsletter, the illustration archives of the Mayo Clinic Division of Creative Media, staff biographies, curriculum vitae, personal interviews, as well as full-text journal articles, and book publications was performed. Dr Rhoton was engaged in a busy clinical practice as a young staff at the Mayo Clinic. Records show he focused on tackling complex intracranial pathologies along with numerous basic research and neuroanatomy projects that became a major part of his life's work and passion. He was a great teacher and friend to countless individuals and his work will continue to impact and improve the care provided to neurosurgery patients for generations to come.

Abstract BACKGROUND: Extradural approach to the cavernous sinus, the “Dolenc” approach recognizing its developing Dr. Vinko Dolenc, is a critically important skull base approach. However, resection of the lateral wall of the cavernous sinus, most commonly for cavernous sinus meningiomas, results commonly in a defect that often cannot be reconstructed in a water-tight fashion. This may result in troublesome pseudomeningocele postoperatively. OBJECTIVE: To describe a technique designed to mitigate the development of pseudomeningocele. METHODS: We found the Dolenc approach critical for resection of cavernous lesions. However, a number of pseudomeningoceles were managed with prolonged external pressure wrapping in the early cohort. Therefore, we incorporated subgaleal to muscular sutures, which were designed to close this potential space and retrospectively analyzed our results. RESULTS: Twenty-one patients treated with a Dolenc approach and resection of the lateral wall of the cavernous sinus over a 2-year period were included. Prior to incorporation of this technique, 12 patients were treated and 3 (25%) experienced postoperative pseudomeningoceles requiring multiple clinic visits and frequent dressing. After incorporation of subgaleal retention sutures, no patient (0%) experienced this complication. CONCLUSION: Although basic, subgaleal to temporalis muscle retention sutures likely aid in eliminating this potential dead space, thereby preventing patient distress postoperatively. This technique is simple and further emphasizes the importance of dead space elimination in complex closures.