A case of idiopathic hypertrophic cranial pachymeningitis masquerading as Tolosa–Hunt syndrome in an elderly female

Idiopathic hypertrophic cranial pachymeningitis (IHCP) is an extremely rare clinical entity of unknown etiology, characterized by a chronic inflammation causing thickening of the dura mater.[1] ICHP can produce similar presentation to Tolosa–Hunt syndrome (THS) if it involves cavernous sinus.[2] THS might represent a focal manifestation of IHCP.[2] The THS is a rare syndrome with an estimated annual incidence of one case per million per year.[3] It typically presents with orbital pain associated with palsy of the third, fourth, or sixth cranial nerve. We present an interesting case of a patient with IHCP associated with THS in an elderly female who responded well to high-dose steroids and in a few days had significant improvement in her retro-orbital pain and ocular movements. The importance of appropriate neuroimaging and serological investigation in patients with suspected THS, role of erythrocyte sedimentation rate in follow-up of these patients, and the relationship between IHCP and THS are discussed.