[Sphenoidal hyperostosis. Problems of differential diagnosis: report of a case].

A case of sphenoid hyperostosis is described in a patient whose clinical history and radiological work up suggested fibrous dysplasia. A year later, the biopsy and MRI showed evidence of a meningioma en plaque. Problems in the differential diagnosis are discussed among entities which present sphenoid hyperostosis: osteoma, Paget's disease, sphenoid meningioma and fibrous dysplasia.