prolapsed hemorrhoid

hemorrhoid /hem·or·rhoid/ (hem´ah-roid) prolapse of an anal cushion, resulting in bleeding and painful swelling in the anal canal.

Hemorrhoids: (A), internal; (B), external; (C), mixed; (D), thrombosed.

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external hemorrhoid  one in a vein of the inferior rectal plexus, below the pectinate line and covered with modified anal skin.

internal hemorrhoid  one in a vein of the superior rectal plexus, originating above the pectinate line and covered by mucous membrane.

prolapsed hemorrhoid  an internal hemorrhoid that has descended below the pectinate line and protruded outside the anal sphincter.

strangulated hemorrhoid  a prolapsed hemorrhoid whose blood supply has become occluded by constriction of the anal sphincter.

thrombosed hemorrhoid  one containing clotted blood.

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prolapsed hemorrhoid

Etymology: L, prolapsus, falling; Gk, haim orrhois, a vein that loses blood

an internal hemorrhoid that protrudes through the anal orifice.

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hemorrhoid [hem´ŏ-roid]

an enlarged (varicose) vein in the mucous membrane inside or just outside the rectum; called also pile.

Internal hemorrhoids usually are first noticed when minor bleeding occurs with defecation. Pain occurs rarely, unless there is an associated disorder such as an anal fissure, thrombosis, or strangulation of the affected vein. External hemorrhoids produce varying degrees of pain, feelings of pressure, itching, irritation, and a palpable mass. Bleeding occurs only if the external hemorrhoid is injured or ulcerated and begins to break down.

Hemorrhoids are caused by increased pressure on the veins of the anus. Prolonged sitting, constipation, and hard, dry stools that are difficult to pass can lead to straining and sitting at stool for long periods of time, all of which add pressure on the anal veins. Failure to follow through on the urge to defecate can also lead to hemorrhoids. In women, probably the single most common cause is pregnancy.

External hemorrhoids can be treated by local applications of cold and an astringent cream, by sitz baths, and by avoidance of constipation. Internal hemorrhoids may require sclerosing or cryosurgery to obliterate the affected tissue. More advanced, chronic hemorrhoids usually must be removed surgically by ligation and excision (hemorrhoidectomy) or by barron ligation.

Types of hemorrhoids.

external hemorrhoid one distal to the pectinate line.

internal hemorrhoid one originating above the pectinate line and covered by mucous membrane.

prolapsed hemorrhoid an internal hemorrhoid that has descended below the pectinate line and protruded outside the anal sphincter.

strangulated hemorrhoid an internal hemorrhoid that has prolapsed sufficiently and for a long enough time for its blood supply to become occluded by the constricting action of the anal sphincter.