Petroclival meningiomas resected via a combined transpetrosal approach: surgical outcomes in 60 cases and a new scoring system for clinical evaluation

Abstract

OBJECT Petroclival meningiomas are among the most challenging intracranial tumors to treat surgically. Many skull base approaches have been described to improve resection and decrease patient morbidity. The authors undertook this study to evaluate the results of their treatment of petroclival meningiomas using objective measurements of tumor volume and a new impairment scoring system to assess neurological symptoms that severely affect the patient's quality of life, such as impairment of swallowing and speaking, motor function, and consciousness and communication. METHODS Between January 1990 and December 2009, the authors used a combined transpetrosal approach to treat 60 patients with benign (WHO Grade I) petroclival meningiomas. In this retrospective study, all 60 cases were analyzed in detail with regard to tumor volume, extent of resection (EOR), long-term tumor control, neurological outcome, and the patient condition. In addition, patients were divided into 2 groups according to the period during which the surgery was performed: the early group, from 1990 to 1999, and the late group, from 2000 to 2009. A new scoring system, the petroclival meningioma impairment scale (PCMIS), was created for quantitative assessment of 8 categories of neurological functions, with scores assigned in each category according to the level of disability and its impact on the patient. The PCMIS was used preoperatively, at 3 months after surgery, and at the time of the last follow-up examination, and the results for the 2 groups were compared. RESULTS There were 24 cases in the early group (1990–1999), and the mean duration of follow-up was 149.3 months. The mean EOR was 96.1%, and good long-term tumor control was obtained in 22 patients (91.7%). One of patients died because of a postoperative complication in the perioperative period. The PCMIS improved in 3 patients (12.5%), remained stable in 1 (4.2%), and worsened in 20 (83.3%). There were 36 cases in the late group (2000–2009), and the mean duration of follow-up was 77.9 months. The mean EOR was 92.7%, and good long-term tumor control was obtained in 34 patients (94.4%). The PCMIS score improved in 23 patients (63.9%), remained stable in 5 (13.9%), and worsened in 8 (22.2%). CONCLUSIONS The combined transpetrosal approach has provided satisfactory functional improvements and excellent tumor control for patients with petroclival meningiomas. The PCMIS provides a specific tool for quantitative assessment of the patient's state.