Chiasmal optic neuritis: A report of three cases

Chiasmal optic neuritis (ON), a rare condition that affects the optic chiasm, is mostly associated with inflammatory demyelinating disorders and may be the initial manifestation of multiple sclerosis (MS). Here, we reported three cases of MS with chiasmal optic neuritis. The clinical manifestations, neuroimaging results, and visual prognosis were evaluated in each patient. Routine eye examinations and auxiliary examinations, including Ishihara color plate, determination of the visual field (VF), and magnetic resonance imaging (MRI) of the optic nerve and chiasm, were performed. All patients presented with reduced VA and VF defects. The abnormal enhancement of the optic chiasm was clearly demonstrated on MRI. Two patients recovered after the systemic administration of steroids, but the other patient only partially recovered. In conclusion, although it is rare, chiasmal ON should be considered in patients who develop bitemporal hemianopia. MRI is the modality of choice for accurate diagnosis. Early diagnosis and proper treatment are mandatory for the restoration of restore visual function.