Stroke is a leading cause of death and disability throughout the world. About one in three symptomatic strokes are due to disease of small perforating arteries; however, most effective interventions are targeted at disease of large arteries. The underlying mechanisms and treatment of small vessel disease remain poorly understood. Microbleeds have emerged as a critical imaging marker of small vessel disease, being found in all types of stroke. With increasing evidence that microbleeds are caused by hypertensive arteriopathy and cerebral amyloid angiopathy, they are likely to play a strong...