Growth Types of Sphenoid Wing Meningiomas and Their Importance in Operative Planning

• Main Authors: Bloss, Heinz-Georg, Mayer, C., Proescholdt, M. A, Schreyer, A., Brawanski, A.
• Format: Conference Proceeding
• Language: English
• ISSN: 1531-5010; 1532-0065
• DOI: 10.1055/s-2005-916477

Introduction: In surgery of meningiomas the complete removal of the tumor is a challenging task, especially when dealing with the skull base region. In our study we analyze which anatomical pathways are used as guidelines for tumor growth of sphenoid wing meningiomas. Material and Methods: In our retrospective study we analyzed the preoperative data of CT and NMR for tumor growth. From 1992 until 2001 we operated on 69 patients; the data of 48 patients could be analyzed. The type of growth was divided into bony and soft tissue growth. For bony growth, the following anatomical structures were investigated for tumor invasion: facies orbitalis, facies temporalis, and facies cerebralis of the greater sphenoid wing; the orbital roof; optic canal; clinoid process of the lesser sphenoid wing; superior orbital fissure; and sphenoid sinus. For soft tissue growth, we analyzed intracranial growth, optic canal, cavernous sinus, superior orbital fissure, and intra- and extraperiorbital growth. Results: All patients with soft tissue growth or with bony growth had an intracranial tumor spread, as follows: 15.9% showed only intracranial growth; 34% invaded the cavernous sinus using the medial superior orbital fissure as a pathway; 36.4% used the lateral superior orbital fissure. In 84.1% the tumors showed a bony growth, and 20.5% of those showed only an intracranial growth. Conclusions: We found that 20.5% of bony growth tumors have no soft tissue spread in NMR, their pathways (bony) only visible on CT scans. So we recommend both CT and NMR for an exact preoperative analysis. In particular, the level of operative challenge can be estimated for bony growth.