Retrosigmoid versus middle fossa approach for hearing and facial nerve preservation in vestibular schwannoma surgery: A systematic review and comparative meta-analysis.

BACKGROUND: Vestibular schwannomas (VS) are benign tumors arising from vestibular nerve's Schwann cells. Surgical resection via retrosigmoid (RS) or middle fossa (MF) is standard, but the optimal approach remains debated. This meta-analysis evaluated RS and MF approaches for VS management, emphasizing hearing preservation and Cranial nerve seven (CN VII) outcomes stratified by tumor size. METHODS: Systematic searches across PubMed, Cochrane, Web of Science, and Embase identified relevant studies. Hearing and CN VII outcomes were gauged using the American Academy of Otolaryngology-Head and Neck Surgery, Gardner Robertson, and House-Brackmann scores. RESULTS: Among 7228 patients, 56 % underwent RS and 44 % MF. For intracanalicular tumors, MF recorded 38 % hearing loss, compared to RS's 54 %. In small tumors (<1.5 cm), MF showed 41 % hearing loss, contrasting RS's lower 15 %. Medium-sized tumors (1.5 cm-2.9 cm) revealed 68 % hearing loss in MF and 55 % in RS. Large tumors (>3cm) were only reported in RS with a hearing loss rate of 62 %. CONCLUSION: Conclusively, while MF may be preferable for intracanalicular tumors, RS demonstrated superior hearing preservation for small to medium-sized tumors. This research underlines the significance of stratified outcomes by tumor size, guiding surgical decisions and enhancing patient outcomes.

Natural history and volumetric analysis of meningiomas in neurofibromatosis type 2.

OBJECTIVE: The objective of this paper was to describe the volumetric natural history of meningiomas in patients with neurofibromatosis type 2 (NF2). METHODS: The authors performed a retrospective descriptive study by reviewing NF2 patients with meningiomas at their institution between 2000 and 2019. Demographic data were collected from the electronic medical records. Tumor volume was collected using volumetric segmentation software. Imaging characteristics including peritumoral brain edema (PTBE) and tumor calcification were collected for each patient from their first to most recent MRI at the authors' institution. An increase of 15% or more per year from original tumor size was used as the cutoff to define growth. RESULTS: A total of 137 meningiomas from 48 patients were included in the analysis. The average number of tumors per person was 2.9. Ninety-nine (72.3%) tumors were in female patients. The median length of follow-up from first imaging to last imaging was 32 months (IQR 10.9, 68.3 months). Most tumors were located in the cerebral convexity (24.8%), followed by the falcine region (18.2%) and spine (10.2%). The median tumor growth was 0.12 cm3/yr (IQR 0.03, 0.52 cm3/yr). At the time of first imaging, 21.9% of tumors had calcifications, while 13.9% of meningiomas had PTBE. Of 137 tumors, 52 showed growth. Characteristics associated with tumor growth included PTBE (OR 9.12, 95% CI 1.48-56.4), tumor volume (per cm3) at first imaging (OR 0.91, 95% CI 0.83-0.99), and 10-year increased age at first imaging (OR 0.57, 95% CI 0.43-0.74). PTBE had the shortest median time to growth at 9.2 months. CONCLUSIONS: Although the majority of NF2-associated meningiomas do not grow in the short term, a wide range of growth patterns can be seen. Younger age at first imaging and presence of PTBE are associated with growth. Patients with these characteristics likely benefit from closer follow-up.

Reconstruction after extended endonasal approaches to the anterior cranial base: surgical techniques and current results.

The development of extended endoscopic endonasal approaches (EEA) to the anterior skull base has allowed successful resection of selected extradural and intradural skull base tumors through an endonasal corridor, minimizing brain and cranial nerve manipulation. However, as the complexity of the approaches has increased, so has the need for more robust and reliable reconstructive options to minimize morbidity. Reconstructive decision-making after extended EEA for anterior skull base tumors must take into consideration multiple factors including patient characteristics (Body Mass Index, previous surgeries, and radiation), location and the size of the skull base defect. A multilayered reconstruction which includes a combination of free grafts and a vascularized flap is the standard approach to anterior skull base defects after EEA and should be applied in a stepwise manner tailored to each patient. The techniques and materials used to accomplish skull base repair are discussed, the outcomes in the literature are reviewed, and our reconstructive paradigm presented.