OBJECTIVE: Despite Cushing's accurate description of the anatomic origin of tuber-culum sellae meningiomas, many subsequent authors have included tumors originating from the neighboring Sella region in this classification. This has led to difficulty in evaluating the surgical results and consensus for an optimal surgical technique. W e think this confusion has arisen from Cushing's description of these tumors under,the heading "suprasellar meningiomas," which referred-to their distinctive clinical symptoms toms and not their anatomic origin. We describe the microsurgical anatomy and tumor, growth patterns to reemphasize the original classification of Cushing's tuberculum sellae meningiomas. Additionally, we describe our surgical approach, which creases the risk of injury to anterior visual pathways and anterior cerebral circulation arteries. METHODS: During a 19-year period, 23 patients with meningiomas arising frond the, tuberculum and diaphragma sellae underwent craniotomies at New, York Medical Center. The tumor size ranged from 2 to 5 cm. All patients p resented with symptoms of visual dysfunction; 15 were asymmetrical. Magnetic resonance imaging with and without gadolinium differentiated these tumors from other suprasellar tumors with a high degree of accuracy. All patients underwent a pteriona transsylvian approach. RESULTS: Twenty. patients had total tumor removal, and three had subtotal tumor removal. There was one regrowth in the subtotal tumor removal group. Patients were observed for a mean follow-up time of 9.3 years (range, 3.6-18.5 yr). Visual improved in 55%, was unchanged in 26%, and worsened in 19% of patients. Two of the oldest patients died from pulmonary complications, resulting in a mortality, rate,of 8.7%. CONCLUSION: We think that tuberculum and diaphragma sellae meningiomas are, anatomically indistinguishable and should be termed tuberculum sellae meningioma. A pterional craniotomy with microsurgical dissection of the sylvian fissure access to these tumors with minimal neurological and ophthalmological morbidity.