Clinical characteristics and results of surgical treatment of petroclival meningioma

Abstract

The size of meningioma and its relation with neurovascular structures in petroclival region stipulate the degree of surgical radicalism and determine an operation risk. In spite of progress of surgical technology, the rate of surgical morbidity in view of cranial nerves deficit is 30%-50%. The objective of our study was to present the results of treatment of patients with petroclival meningiomas and to point to correlation of preoperative radiological findings and intraoperative results as well as neurological status of patients before and after surgical treatment. Retrospective analysis of 35 operated petroclival meningiomas at the Institute of Neurosurgery, CCS, in the period from 1995 to 2004 was presented. The following parameters were analyzed: size of tumor, relation with bone and neurovascular structures, preoperative condition, degree of surgical radicalism and postoperative outcome. The size of tumor was classified in four groups. There were 20 tumors at the right, and 15 at the left side. At the time of diagnostic procedures (based on CT and MRI), 20 tumors were in contact with brainstem, 9 compressed the brainstem, and 6 obstructed the IV ventricle. Preoperative patient condition was evaluated by Karnofsky index. Mean value for group I was 90, II - 80, III - 70 and IV - 50. In 9 cases, liquor drainage was performed preoperatively. In 3 cases, external liquor drainage was carried out postoperatively, and in one case it was replaced by permanent liquor drainage. Radical operation was performed in 44%, and significant reduction was done in other cases. In the postoperative period, 11% patients died, 28% had cranial nerves deficit, and pyramid deficit was recorded in 14% of the patients. The tumor size (III-IV) and brainstem compression were found to be statistically significant (p<0.05) as predisposed factors of deficit prolongation. Petroclival meningoma surgery is required upon precise preoperative analysis. Radicalism of operation is reserved for small and medium tumors, younger patients, and patients in good preoperative condition