Idiopathic hypertrophic cranial pachymeningitis mimicking multiple meningiomas: case report and review of the literature.

A case of idiopathic hypertrophic cranial pachymeningitis with an unusual and misleading manifestation is reported. Computed tomography scan, angiographic and magnetic resonance imaging findings were suggestive of multiple meningeal neoplasms and a correct diagnosis was made only after meningeal biopsy. This 44-year-old patient had a previous history of an ill-defined systemic disorder associating episcleritis, erythroderma nodosa and multiple peripheral arthritis. We review previous reports of idiopathic cranial pachymeningitis with emphasis on radiological investigation techniques, histopathology and possible dysimmune mechanisms of pathogenesis.