Abstract
Thiamine (vitamin B1), a critical cofactor for carbohydrate metabolism and neurotransmitter synthesis, plays an indispensable role in neuro-ophthalmic health. Deficiency of this crucial nutrient, while traditionally associated with a range of neuro-ophthalmic symptoms, can often lead to clinical presentations that are far from typical. In this case series, we delve into the unique experiences of three young men who developed uncommon neuro-ophthalmic manifestations due to thiamine deficiency following rapid weight loss due to strenuous exercises. Involvement of the optic nerve, presenting as either optic neuritis or papilledema, stands as an unusual revelation of thiamine deficiency; the insidious nature of imaging abnormalities, which require time to manifest, poses an additional diagnostic challenge. It is crucial to recognize that factors such as rapid weight loss and strenuous exercise can precipitate thiamine deficiency, potentially hastening the onset of its neuro-ophthalmic manifestations. Prompt recognition and intervention are essential to mitigate the risk of permanent neurologic deficits, emphasizing the imperative need for awareness and vigilance among healthcare practitioners. Through this series, we aim to augment the understanding of this under-recognized clinical entity.