Abstract: Methods and apparatuses for embolizing an artery in a living subject using a catheter are disclosed. The catheter has a lumen and also has a balloon located near the distal end of the catheter. The distal end of the catheter is introduced into the artery, and the balloon is inflated to form a seal that prevents blood in the artery from flowing past the balloon. A mixture that includes embolic particles and contrast agent is injected through the lumen into the portion of the artery that is distally beyond the balloon. The subject's own blood or another fluid that contains platelets is injected through the lumen into the portion of the artery that is distally beyond the balloon. Subsequently, the balloon is deflated and the distal end of the catheter is withdrawn.