Optic neuropathy caused by thiamine deficiency in a patient with malnutrition

A 52-year-old man complained of decreased visual acuity in both eyes. He had not maintained a balanced and adequate diet for several months. Visual field tests showed centrocecal scotoma in the right eye and central scotoma in the left eye. Results of laboratory tests showed low serum thiamine level. His visual acuity and visual field abnormality improved after supplementation with multivitamin tablets containing thiamine. Ophthalmologists should be aware that thiamine deficiency-induced optic neuropathy may develop in patients with inadequate and unbalanced diets.