Surgical Treatment for Clinoidal Meningiomas

• Main Authors: Minamida, Yoshihiro, Mikami, T., Yamaki, T., Houkin, K.
• Format: Conference Proceeding
• Language: English
• ISSN: 1531-5010; 1532-0065
• DOI: 10.1055/s-2005-916457

Introduction: Clinoidal meningiomas are frequently associated with a high mortality and morbidity rate, failure of total removal, and recurrence. Recent advances in cranial base surgery have enabled and facilitated radical resection. In this retrospective study, the surgical results and visual outcomes were investigated in 18 patients who underwent surgical treatment at our institution. Material and Methods: A retrospective analysis was performed on18 consecutive patients with clinoidal menigiomas who underwent surgical resection at our institution from January 1996 to December 2004. A pterional approach with cranial base modifications including extradural anterior clinoidectomy and unroofing of the optic canal was adopted in all patients. Involvement of the internal carotid artery was classified into four categories according to modified Hirsch grading system. Sites of origin were classified into three categories according to Al-Mefty's classifications. All patients had preoperative and postoperative ophthalmological evaluations. The follow-up period ranged from 2 to 96 months (mean: 48.6 months). Results: Total resection was achieved in 13 patients (73%). There were no cases of mortality and the rate of visual improvement was 76% in patients with preoperative visual impairment. In all 5 patients who had tumors encasing the internal carotid artery (Hirsch Grades 2 to 4), total resection could not be accomplished. Karnofsky Performance Scale scores were over 80 in most patients (94%) at the last follow-up period. Among 5 patients in whom total resection was not achieved, 2 patients were treated with stereotactic radiosurgery after operation. One patient developed a growth of tumor. Conclusions: With the use of the skull base technique, total resection and improvement of visual function could be achieved with minimal morbidity in most patients with clinoidal meningiomas. However, total resection could not be achieved in patients with tumor encasing the internal carotid artery, and adjuvant therapy should be considered postoperatively.