Idiopathic hypertrophic cranial pachymeningitis: Clinicoradiological spectrum and therapeutic options

OBJECTIVE: Idiopathic hypertrophic cranial pachymeningitis is a rare diseas e, of undetermined pathogenesis, that is characterized by inflammation and fibrosis of the dura mater. METHODS: We encountered six patients with idiopathic hypertrophic cranial p achymeningitis and analyzed their clinical presentations, radiological find ings, and treatment. RESULTS: In the six patients, the main manifestations were cranial nerve pa lsies and headache. Three associations were present, namely optic neuropath y, Tolosa-Hunt syndrome, and diabetes insipidus. Gadolinium-enhanced magnet ic resonance imaging was diagnostic, showing intense dural enhancement in a linear or nodular pattern. The responses to corticosteroid therapy were be tter for patients who exhibited linear, rather than nodular, dural enhancem ent. For one patient, surgical decompression of the superior orbital fissur e provided lasting relief. The course of the disease followed one of three patterns, i.e., sustained remission, relapse with corticosteroid independen ce, or relapse with corticosteroid dependence. Pulse corticosteroid therapy provided significant relief, while reducing the daily corticosteroid requi rement and avoiding side effects, for a corticosteroid-dependent relapsing patient. CONCLUSION: Idiopathic hypertrophic cranial pachymeningitis exhibits varied clinical courses. It is important to prevent irreversible cranial neuropat hy during the active phase of the disease, using daily administration of co rticosteroids, pulse corticosteroid therapy, or surgical decompression.