Optic perineuritis.

Purpose Of Review: This review paper aims at discussing pathogenesis, etiology, clinical features, management, and prognosis of OPN.

Recent Findings: Optic perineuritis (OPN) is an inflammatory process primarily involving the optic nerve sheath. Clinically, OPN usually presents with unilateral, gradual decline of visual function, eye pain, and/or pain on eye movements, disc edema and various features of optic nerve dysfunction, including visual field defects. It can mimic typical optic neuritis. In most cases of OPN, the disease is isolated with no specific etiology being identified, however, it can also occur secondary to a wide range of underlying systemic diseases. OPN is clinically diagnosed and radiologically confirmed based on the finding of circumferential perineural enhancement of the optic nerve sheath on magnetic resonance imaging (MRI).

Summary: Unlike optic nerve, OPN is not typically self-limited without treatment. High-dose oral corticosteroids are the mainstay of treatment in OPN. The initiation of therapy usually causes rapid and dramatic improvement in signs and symptoms. In general, OPN usually has a relatively good visual prognosis, which is influenced by delays between the onset of visual loss and the initiation of steroid therapy as well as the presence of underlying systemic diseases.