Posterior fossa meningioma (surgical experiences)
Introduction: Meningioma is a common tumor that represents about 30% of all intracranial tumors. Posterior fossa location of the tumor is uncommon. It can be classified according to the location in the posterior fossa into cerebellopontine angle, clival, petroclival, convexity, tentorial and foramen magnum. Different surgical approaches are used to excise these tumors.
Aim of the study: Was to study different aspects of posterior fossa meningioma regarding location, histology, surgical approaches and outcome.
Methods: Retrospective study including 20 patients diagnosed with posterior fossa meningioma was included in the study. Data were obtained from the files of the patients and were analyzed. All patients had preoperative complete general and neurological examination, MRI of the brain with and without Gadolinium. Different surgical approaches were utilized in the study depending on the tumor location and the surgeon’s preference. Postoperatively, all patients had a postoperative CT scan of the brain with contrast. Some patients had also MRI of the brain with and without Gadolinium.
Results: Fifteen of the patients were females and 5 were males. The age ranged from 35 to 69. Symptoms included headache (75%), cerebellar manifestations (60%), cranial nerve affection (40%) and hearing disturbances (15%). Most of the cases (50%) were cerebellopontine angle meningioma while the least (5%) were foramen magnum meningioma. Surgical approaches used included retrosigmoid approach (50%), transpetrosal approach (30%) and transcondylar approach (20%). Tumor removal was total in 60% of cases and partial in 40%. Postoperative mortality was present in 5% of cases. Morbidity included decreased level of consciousness, cranial nerve palsy and wound infection.
Conclusion: Retrosigmoid approach is effectively and safely used for cerebellopontine angle meningioma, convexity menigioma and lateral tentorial meningioma extending inferiorly to the posterior fossa. Suboccipital approach can be used safely for posterior foramen magnum meningioma. Clival and petroclival meningioma carry a high morbidity incidence.
Keywords: Meningioma; Posterior fossa; Retrosigmoid approach; Transpetrosal approach