EFFECTS OF USING COMBINED TRANSPETROSAL SURGICAL APPROACHES TO TREAT PETROCLIVAL MENINGIOMAS

Abstract

Surgical treatment may be required for large petroclival meningiomas; however, surgery for these lesions is a major undertaking, and modern surgical approaches are still associated with considerable morbidity and recurrence rates. We analyzed our series of transpetrosally operated petroclival meningiomas to obtain detailed information regarding the surgery outcomes with respect to facial nerve effects, hearing changes, general neurological and psychosocial differences, and recurrence rates to identify opportunities for improvement. Between 1994 and 2004, we used transpetrosal approaches to operate on 29 patients for petroclival meningiomas larger than 30 mm. All patients were analyzed in detail regarding neurological outcomes and hearing abilities after surgery. Swedish-speaking patients were contacted for a psychosocial follow-up evaluation using the short-item 36 (SF-36) form. After surgery, the Glasgow Outcome Score improved in 14 patients, was unchanged in 11 patients, and worsened in four patients. Facial nerve function was found to be of House-Brackmann Grade 3 or worse in six patients (including three individuals with transcochlear surgery and facial nerve rerouting). Of the 23 patients who underwent hearing-preservation surgery, serviceable hearing was preserved in 17 individuals. Nineteen Swedish patients were contacted for psychosocial evaluation. Three patients could not participate for health reasons; of the remaining 16 patients, 12 reported physical health scores that were below mean values for the general population. For patients who did not experience very serious neurological compromise, we found that unexpected painful trigeminal neuropathy and unilateral swallowing difficulties conveyed a negative influence on health. Three years after surgery, the patients reported more normalized health scores. Generally, outcomes compared well with current reports. Outcomes can be improved, however by improving patients' psychosocial support; striving to decompress, preserve, and minimize dissection of ill-defined planes of cranial nerves; and using Simpson Grade 4 gamma knife approaches when radicality is precluded. Currently, the performance of transpetrosal surgery for petroclival meningiomas is a major undertaking that significantly affects a patient's health for several years; however, the approaches that we used allowed a high degree of tumor control with relatively little neurological morbidity.