CT enhancement is actually done through iodine-containing contrast agent into the body, and the blood supply is different for each organ or organ after a lesion occurs. CT enhancement actually reflects the blood supply of the organ or lesion, and after the lesion occurs, the blood vessels inside the rich blood supply have a different color. For example, hemangioma in the liver is mainly a network of tortuous vessels. For example, hemangioma in the liver is mainly a tortuous vascular network. The contrast can go in very early, but it takes longer to overlap, so there is a more typical “early out and late in” pattern of enhancement.