Stereotactic radiosurgery for Koos grade IV vestibular schwannoma: a systematic review and meta-analysis.

Background: Stereotactic radiosurgery (SRS) is a well-established treatment option for Koos stage I-III vestibular schwannomas (VS), often used as the first line of treatment or after subtotal resection. However, the optimal treatment for Koos-IV VS remains unclear. Therefore, our study aimed to evaluate the effectiveness of SRS as a primary treatment for large VS classified as Koos-IV.