Dysthyroid Optic Neuropathy

Dysthyroid optic neuropathy (DON) is a serious complication of thyroid associated orbitopathy that can result in irreversible and profound visual loss. Controversy exists regarding the pathogenesis and management of the disease. The mechanism of DON appears to be multifactorial: direct compression of the optic nerve by enlarged extraocular muscles, orbital pressure, vascular insufficiency, and inflammation. Some or all of these factors may be involved in an individual patient. The diagnosis and management of which is complex and requires a multidisciplinary approach. There is little evidence regarding the optimum management strategy. Based on the current literature, the first line of treatment is intravenous methylprednisolone, with the exact timing and indication of bony orbital decompression still to be determined. In addition, there may be a role for the use of biologic agents that will require a systematic program to determine efficacy.