Comparative study of microsurgery and Gamma-Knife surgery in patients with vestibular schwannoma

Abstract

Introduction: Vestibular schwannomas (VSs) are benign neoplasms of Schwann cell origin. Although benign in nature, the treatment of vestibular schwannoma remains a challenge for modern neurosurgery. Patients with vestibular schwannomas have several management options including observation, surgical resection, stereotactic radiosurgery, fractionated radiation therapy, or combinations of these. Material and methods: We study two patient groups that have been treated using either GammaKnife radiosurgery or microneurosurgery. We analyze the criteria for primary referral to one of the thera­peutic procedures and look at their results in terms of tumor control and facial nerve function preservation. The surgical group consisted mostly of patients with equal or bigger than 3 cm (80,95%) tumors out of which 80,95% showed imagistic or clinical signs of brainstem compression. The radiosurgery group consisted exclusively of tumors smaller than 3 cm. Facial nerve function preservation results were unsatisfactory in the surgical group but were good for the patients referred to radiosurgery. Results: Our results show that tumor size is a major factor in facial nerve function preservation. However for large tumors surgery is the only possible therapeutic method. Conclusions: For those patients with smaller tumors and very good preoperative neurological function radiosurgery should be the therapy of choice, keeping in mind that in 12% of the cases in our series there has been an enlargement in tumor volume that could raise the indication for microneurosurgery.