Endoscope-assisted surgery for acoustic neuromas (vestibular schwannomas):Early experience using the rigid Hopkins telescope

OBJECTIVE: Endoscopes have been increasingly used during neurosurgical proc edures. Previously, they have been shown to offer better visualization than the microscope in selected situations and frequently have allowed less inv asive surgery. This study was undertaken to determine whether endoscopy is safe and effective during suboccipital surgery for vestibular schwannomas. METHODS: Ten patients with vestibular schwannomas underwent suboccipital tr ansmeatal craniotomies for tumor excision. Endoscopy with a rigid glass len s endoscope (Hopkins telescope) was used during tumor removal to examine po sterior fossa neurovascular structures and after tumor excision to inspect the internal auditory canal. RESULTS: Complete tumor excision was achieved in nine patients. Endoscopy a llowed improved identification of tumor and adjacent neurovascular relation ships in all cases without the need for significant retraction of the cereb ellum or brain stem. In addition, residual tumor at the fundus of the inter nal auditory canal (n = 2) and exposed petrous air cells (n = 3) not seen w ith the microscope were identified endoscopically. Operative time was not s ignificantly increased by incorporating the endoscope. CONCLUSION: Posterior fossa endoscopy can be performed safely during surger y for tumor removal. Endoscope-assisted surgery for vestibular schwannomas may offer some advantages over standard microsurgery in selected cases. The advantages may include improved visualization, move complete tumor removal , and a lowered risk of cerebrospinal fluid leakage.