Optic neuritis: clinical analysis of 27 cases.

We retrospectively reviewed 27 cases diagnosed as idiopathic optic neuritis between 1992 and 2001 at Kaohsiung Veterans General Hospital to assess the clinical features, visual prognosis, neuroimaging, laboratory studies, and development of multiple sclerosis in Chinese patients with optic neuritis. Patient age ranged from 13 to 54 years (mean, 35.8 +/- 11.3 years). Five cases presented as bilateral optic neuritis and 22 as unilateral. Visual function improved gradually from 2 weeks after treatment. Twelve (44.4%) cases showed disc swelling and ocular pain was also noted in 44.4% of patients. All cases that underwent visual field and visual evoked potential tests showed abnormality in lesion eyes. Of the 23 cases that underwent neuroimaging studies, including computerized tomography (17 patients) and magnetic resonance imaging (6 patients), 10 revealed optic nerve thickening. Four cases (14.8%) developed multiple sclerosis during follow-up (mean, 4.3 years). The incidence of disc swelling was higher than that reported by the Optic Neuritis Treatment Trial, but the incidence of initial ocular pain, the presence of periventricular plaques, and the development of multiple sclerosis were lower in our study. The unilateral group had significantly better visual outcome than the bilateral group.