Homonymous hemianopsia as the initial manifestation of multiple sclerosis.

A 28-year-old male patient in good health with no previous neurologic or ophthalmoscopic abnormalities developed right homonymous hemianopsia. Magnetic resonance (MR) imaging demonstrated bilateral high-signal suprageniculate lesions. The lesion located in the left parieto-occipital area was compatible with the field defect observed. Oligoclonal bands were present in the cerebrospinal fluid. Testing of visual-evoked potentials revealed increased latencies in both eyes. The patient was given 1 g/day intravenous methylprednisolone for 3 days. The visual fields, as determined by automated static perimetry, recovered completely in 2 weeks. Follow-up MR imaging at 1 month showed no change compared to baseline. Seven months after the initial attack he suffered right internuclear ophthalmoplegia, which resolved spontaneously within 1 week. Based on the clinical and radiologic findings, the final diagnosis was made as clinically definite multiple sclerosis (MS). This patient represents a rare case of MS presenting first with homonymous hemianopsia.