Meningiomas of the tuberculum and diaphragma sellae

Introduction Although tuberculum sellae (TS) and diaphragma sellae (DS) meningiomas have different anatomical origins, they are frequently discussed as a single entity. Here we review the radiologic and intraoperative findings of TS and DS meningiomas and propose a radiologic classification. Methods We retrospectively reviewed 10 consecutive TS and DS meningiomas. Data regarding clinical presentation, preoperative imaging, and intraoperative findings were analyzed. Three sellar dimensions were measured on magnetic resonance imaging (MRI): the tuberculum-sellar floor interval (TSFI), the planum-tuberculum interval (PTI), and the total height. Results Three distinct anatomical patterns were recognized: exclusively tubercular meningiomas (type A) were accompanied by elongation of the TSFI and, more significantly, of the PTI; combined TS and DS meningiomas (type B) were associated with relative elongation of both the PTI and TSFI; and the sole exclusively DS meningioma (type C) was associated with elongation of neither PTI nor TSFI. Conclusion Suprasellar meningiomas can be classified as tubercular, combined, or diaphragmatic based on preoperative MRI. Exclusively tubercular meningiomas (type A) require only a supradiaphragmatic approach. Tumor involvement of the sellar diaphragm (type B or C) requires resection of the diaphragm and thus a combined infra- and supradiaphragmatic approach.