Diplopia With Dural Fibrotic Thickening.

Idiopathic hypertrophic pachymeningitis (HP) is a rare disorder of diffuse thickening of the cranial or spinal dura mater without an identifiable cause. Most common in adult males, idiopathic HP typically presents with headache with or without varied associated focal neurologic deficits and findings of dural enhancement on magnetic resonance imaging in a linear, nodular, or combined pattern. As it is felt to be an autoimmune disorder, treatment with high-dose corticosteroids is typically recommended, and without intervention, the course is usually progressive. The disease can commonly progress with a relapsing remitting course requiring other immune modulators such as methotrexate, azathioprine, or cyclophosphamide for control. Here, we describe a unique case of idiopathic HP as it presented in a pediatric patient and resolved without immunomodulatory therapy.