Botulinum toxin-A (BTX-A) is widely used for aesthetic purposes and is recognized for its vasomotor actions. However, new medical applications have emerged. This study aims to describe the effect of BTX-A on human skin perfusion, particularly vessel diameter, blood flow, and blood vessel density in regions with known low vessel density. This case series involved 40 patients who were treated with subcutaneous injections of BTX-A and sodium chloride 0.9% into marked skin areas on their backs. …