Why do crescent-shaped RBCs lead to vessel occlusion?

Crescent-shaped red blood cells (RBCs) are characteristic of sickle cell disease. These abnormally shaped cells fail to flow smoothly through blood vessels, particularly in smaller capillaries. As they deform and lose their flexibility, they are prone to clumping together. This clumping can create a blockage or "sludge," which obstructs blood flow, leading to vessel occlusion.

Once these sickle-shaped cells aggregate, they can effectively hinder circulation in affected areas, resulting in pain and potential tissue damage due to insufficient oxygen supply. The importance of this option lies in understanding the mechanics of blood flow and the implications of abnormal red blood cell morphology on vascular health, particularly in the context of conditions like sickle cell disease.