Optic neuritis with normal visual acuity – A case report

Abstract

Background: Optic neuritis is an acquired disorder of the optic nerve due to inflammation or demyelination. Diagnosis of optic neuritis was based mainly on clinical signs and symptoms, ancillary tests only help confirm the diagnosis or follow treatment progress. However, in cases with high visual acuity and with mild or without optic disc edema, the disease can be easily underdiagnosed. Case report: We report a case of optic neuritis with normal visual acuity. The patient complained of blurring vision and mild pain in her right eye upon gazing; however, her right eye best corrected visual acuity was 20/20. Ishihara color vision test was 20/24 on her right eye and 24/24 on her left eye. Relative afferent pupillary defect was detected, fundus examination revealed mild optic disc edema, and visual field test showed enlarged physiological blind spot on her right eye. The patient received careful follow-up with no corticosteroids treatment. After 3 months, all the signs and symptoms resolved completely. Conclusion: This case demonstrated that optic neuritis can be easily underdiagnosed; relative afferent pupillary defect check, visual field, magnetic resonance imaging and color vision test should be performed in every suspected cases. Strict follow-up check, instead of corticosteroids may be of priority when patient visual acuity is still good.