Surgery of Anterior Clinoidal Meningiomas

Objective: Microsurgery of anterior clinoidal meningiomas (ACM) is associated with significant mortality/morbidity rates and frequent failure of total removal. Study Design: Authors retrospectively analyze clinical and radiological findings, discuss key surgical steps for minimizing postoperative morbidity and evaluate functional outcome. Patients and Methods: Between 2008 and 2012, 13 patients with ACM were operated in our institution, including 5 giant tumors with maximal diameter over 50 mm. Four tumors were removed by the orbitozygomatic approach, in 9 cases the minipterional craniotomy was utilized, complete anterior clinoidectomy was necessary in 3 patients. Results: Simpson grade I resection was achieved in 1 patient, grade 2 in 10 patients and small residual tumor in cavernous sinus was left in 3 cases. Three months after surgery, all patients were GOS 5 with no permanent neurological deficit. Visual acuity improved in four patients, three patients’ experienced temporary oculomotor palsy, and one temporary visual deterioration. Subdural collection was evacuated in one case and in one patient preoperative epileptic seizure persisted. In a relatively short follow-up, no recurrence occurred and three residual tumors showed no progression and need for further treatment. Conclusion: Although, ACMs represent a challenging skull base tumors often encasing important neurovascular structures, their radical removal is possible with good functional outcome in most cases.