Surgical treatment of petroclival meningioma with special reference to timing of radiosurgery for residual tumor

Abstract

Introduction: To avoid any morbidity occurring by the surgery for petroclival meningioma, our treatment strategy is (1) the tumor should be left undetached in the case there is no CSF space between tumor and the surrounding structures, to avoid new deficit, (2) the residual volume should be reduced to less than 20 ml, that is, small enough for radiosurgery. The result of our strategy will be presented. Methods: During the past 5 years, we have experienced 13 patients with petroclival meningioma. The tumor volume ranges from 1.0 to 70 ml. Eight patients had neurological deficits preoperatively. Ten patients underwent the anterior petrosal approach while two patients underwent the far lateral approach, according to the tumor attachment. Results: The tumors were totally removed in five patients. The surgical removal had successfully decreased the tumor size in eight patients. The residual volume was small enough (less than 20 ml) just after the surgical removal in each case. Thus, the radiosurgery followed within 3 months after the open surgery in six patients. The residual tumor has almost disappeared in one case and decreased in five cases. No new deficit occurred other than a transient facial weakness in one case and an oculomotor palsy in the other. Conclusion: It is concluded that our planned surgical treatment of the petroclival meningioma is safe and sure in terms of the patients' quality of life. The planned radiosurgery for the residual tumor immediately after the surgical removal is considered most effective.