Introduction: Meningiomas-en-plaque (MEP), first coined by Cushing in 1922, comprise 2.5% of all meningiomas. While they typically arise in the sphenoid wing, convexity MEP’s are comparatively rare and are often confused with meningeal sarcoidosis, osteoma, tuberculoma, and fibrous dysplasia with very little information published in the literature.
Methods: We conducted a literature review on PubMed from its origin to January 2015 including all language articles using the keyword search “convexity, meningioma en plaque, parasagittal, and cranial vault.” All studies that described reports of convexity MEP were reviewed for patient demographics, presenting symptoms, radiological reports, surgical management, recurrence rates, histopathological presentation, post-operative complications, and follow up. This resulted in ten papers comprising seventeen cases of convexity MEP.
Results: Fourteen (82%) of the 17 patients were female with average age of 49.5 years. Intitial presenting symptoms included headache 11/17 (65%), hemiparesis 3/17 (18%), and visual symptoms 2/17 (12%). 16/17 (94%) patients exhibited hyperostosis with diffuse hyperostosis seen in 19%. Two patients underwent subtotal resections followed by radiotherapy. Twelve cases had pathology reports associated with all 12 tumors graded as WHO Grade I: 5 meningothelial, 5 fibroplastic, and 2 transitional.
Conclusions: Convexity MEP, while rare, present a challenge with regard to correct diagnosis and subsequent resection. The easier accessibility of these meningiomas predicts higher surgical success rates and incidence of total resection, though care must be taken to ensure gross removal of tumor, dural attachments, and any overlying hyperostotic bone. Though hyperostosis is frequently observed with this variant of meningioma, it is neither exclusive or wholly indicative of MEP and various imaging modalities are used to differentiate MEP from other pathological conditions such as fibrous dysplasia. Due to its rarity in both clinical practice and the literature, further studies are warranted to identify modern imaging means to correctly diagnose this condition.
Patient Care: Identify convexity MEP's correct diagnosis and subsequent treatment.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) appreciate the rarity of convexity MEP, 2) ensure proper diagnosis of convexity MEP to guide appropriate treatment.