Microsurgical excisions of vestibular schwannomas: A tumor-size-based analysis of neurological outcomes and surgical complications

Introduction: Vestibular schwannomas (VS) are benign tumors originating from Schwann cells in vestibulocochlear nerve. This study aimed at evaluating outcomes of microsurgical resections of VS based on tumor sizes in a South Asian country.Methods: The chart notes of 71 Patients who underwent microsurgical resections of VS at a single academic center over a 20-year period (1990-2009) were reviewed, and relevant information was extracted. For analyzing outcomes, Patients were divided into two groups based on tumor size at initial presentation: (1) Group A (tumor size ≤ 4 cm) and (2) Group B (tumor size > 4 cm). Pearson's chi-square and Fisher's exact tests were used for comparison of proportions, the independent sample t-test was used for comparison of means.Results: The average tumor diameter was 4.1 1.5 (range, 1-6.6) cm. Complete resection was achieved more frequently in Patients in Group A (P < 0.001). Duration of hospital stay and cost of treatment were significantly higher in Group B Patients (P < 0.003 and P < 0.04, respectively). The severity of postoperative facial nerve injury, assessed by House-Brackmann grading system, was significantly higher in Group B (P < 0.01). Cerebrospinal fluid (CSF) leak and lower cranial nerve deficits also occurred more frequently after resection in Group B (P = 0.031 and P = 0.003, respectively).Conclusion: We conclude that advanced stage tumors suggestive of delayed presentation are fairly common in Pakistan, and limit curative resection in the majority of Patients. Postoperative morbidity is significantly higher in Patients with tumor size > 4 cm.