Potential cost of assumptions within a visual assessment.

We report a man in his 80s who described sudden unilateral loss of vision, resulting in extensive urgent investigations by the accident and emergency department team. Subsequent evaluation of visual acuity with pinhole demonstrated significant improvement, triggering further questioning. It transpired that he was mistakenly wearing his wife's glasses, which accounted for his visual symptoms. This case illustrates the importance of a stepwise approach to visual assessment, and avoiding assumptions, as using the simple pinhole test could have avoided extensive investigations and their subsequent costs.