Sphenoid Wing Meningioma: Proposing Modification to Cushing Classification System Based on Results of 29 Consecutive Patients

Abstract Cushing and Eisenhardt first classified globoid sphenoid wing meningiomas (SWM) into medial, middle and lateral groups. The authors examined 29 consecutive patients with globoid shape SWMs that were surgically treated by the senior author (NG). Based on our results, we would like to modify Cushing's classification system of globoid SWM. All patients who had undergone surgery at two hospitals between 2000 and 2017 were identified. All data from different tumor locations along the sphenoid ridge were compared to determine whether these tumors had different behaviors in presenting symptoms, surgical observation and post-op surgical outcomes. All 29 consecutive patients with globoid shape of SWM underwent microsurgical resection during this period. The rates of cavernous sinus (CS) invasion (medial 46.1%, lateral 0%, pterional 0%; p 0.01) and vascular encasement (medial 76.9%, lateral 36.3%, pterional 0%; p 0.008) were all highest in medial SWMs. Gross total removal (GTR) was found less in medial SWMs (medial 23%, lateral 63.6%, pterional 100%; p 0.008). Complication rate was higher in medial SWMs (medial 53.8%, lateral 18.1%, pterional 20%, p 0.04). Visual impairment was higher in medial SWMs (medial 92.3%, lateral 36.3%, pterional 40%; p 0.01). The authors report different entities of meningiomas located along the sphenoid wing, including the presenting symptoms, imaging studies, microsurgical observation, extension of surgical resection, surgical outcome and surgical complication. Our results support the idea to modify Cushing's classification system.