Intracranial pachymeningitis: CT and MRI aspects

Introduction. Intracranial pachymeningitis (ICPM) is a relatively rare secondary or idiopathic chronic inflammatory thickening of the dura-mater. We report CT-scan and MRI findings. Patients and methods. We report a study of 12 cases observed in the department of neuroradiological at the Rabat hospital (Morocco) over a period of 2 years. CT-scan and MRI were available for all patients, before and after contrast injection. Results. All the patients were female (mean age = 40 years). Imaging disclosed localized and asymmetrical (n = 6) or diffuse (n = 4) meningeal thickening, intensely enhanced after contrast injection. Associated intraparenchymatous lesions (n = 5) and/or clinicobiological abnormalities (n = 6) were found, helping determine etiology. ICPMs were secondary to sarcoidosis (n = 3), tuberculosis (n = 2), Behcet disease (n = 1), Horton disease (n = 1), chronic intracranial hypotension (n = 1) and leptomeningeal carcinomatosis (n = 1). The other cases were idiopathic (n = 3). An intracanalar extension was noted in two cases. Conclusion. Intracranial pachymeningitis is rare, and the etiological diagnosis can be difficult if there is no particular pathological context. Dura-mater biopsy is necessary to confirm idiopathic cases. © 2012 Elsevier Masson SAS.