Microsurgical removal of a vestibular schwannoma after stereotactic radiosurgery: Surgical and pathologic findings

Objective: The objective of this study was to provide objective evidence of the enhanced difficulty of preserving the facial nerve in patients who need microsurgery after failed stereotactic radiosurgery (SRS) of vestibular schwannoma. Study Design: This study was a retrospective case review. Setting: A tertiary care referral center was the setting for the study. Patients: The authors present a case of a young woman with a vestibular schwannoma that enlarged 2 years after treatment with SRS. Intervention: Microsurgery via the translabyrinthine approach was used. Results: At surgery, extensive scarring between the facial nerve and tumor capsule was seen, and the nerve could not be identified at all beyond several millimeters proximal to the porus acusticus. Adhesions of the tumor to the ninth and tenth cranial nerves, the brain stem, and the anterior inferior cerebellar artery were also markedly increased. Histologic examination confirmed fibrotic adhesions surrounding the facial nerve. Conclusions: The unusual degree of fibrosis, scarring, and adhesions of the tumor to the surrounding structures after SRS made microsurgical removal of the tumor difficult and preservation of the facial nerve impossible.