A 42-year-old man comes to the office with rectal bleeding. He used to have occasional streaks of blood on the tissue after wiping, but for the past several days he has seen blood dripping into the toilet at the end of defecation. The patient reports chronic constipation and has to strain while having a bowel movement but has no rectal or abdominal pain. He works as a truck driver, and his diet consists mainly of hamburgers and French fries. Abdominal examination is unremarkable. There is no mass or tenderness on digital rectal examination, but anoscopy shows bulging purplish-blue mucosal lesions above the dentate line. Rubber band ligation of the lesions is most likely to involve which of the following?

Question

A 42-year-old man comes to the office with rectal bleeding.  He used to have occasional streaks of blood on the tissue after wiping, but for the past several days he has seen blood dripping into the toilet at the end of defecation.  The patient reports chronic constipation and has to strain while having a bowel movement but has no rectal or abdominal pain.  He works as a truck driver, and his diet consists mainly of hamburgers and French fries.  Abdominal examination is unremarkable.  There is no mass or tenderness on digital rectal examination, but anoscopy shows bulging purplish-blue mucosal lesions above the dentate line.  Rubber band ligation of the lesions is most likely to involve which of the following?

Quizplus · Accepted Answer

11ec160b_3583_9572_9249_e36484098b17_MD0001_00 Hemorrhoids are classified based on their relation to the dentate line in the anal canal, with internal hemorrhoids originating above the line and external hemorrhoids below. They result from abnormal distension of the anal arteriovenous plexus, which normally forms the anal cushions (composed of venous sinusoids and connective tissue) that are important for maintaining fecal continence. Chronically increased venous pressure due to prolonged straining or breakdown of supporting tissue due to advancing age can cause the cushions to bulge into the anal canal, where they can become inflamed, thrombose, or prolapse. Hemorrhoids can be treated with rubber band ligation, which cuts off the blood supply to the lesions and causes them to degenerate. The venous components of internal hemorrhoids drain into the superior rectal vein, which communicates with the inferior mesenteric vein. External hemorrhoids drain via the inferior rectal vein into the internal pudendal vein, which communicates with the internal iliac veins (Choice D). Internal hemorrhoids have no somatic sensory innervation and cannot cause pain; however, external hemorrhoids are innervated by the same nerves that cover the perianal area and can be very sensitive to pain. (Choice A) Branches of the deep external pudendal artery supply the scrotum (labia majora in females) and the perineum. (Choice B) The external iliac vein receives drainage from the inferior epigastric and deep circumflex iliac veins, which serve the anterior abdominal wall and iliac crest, respectively. (Choice E) The left colic artery branches off the inferior mesenteric artery to supply the transverse and descending colon. (Choice F) The superior vesical artery and its branches supply portions of the urinary bladder and ductus deferens. Educational objective: Hemorrhoids result from abnormal distension of a portion of the anal arteriovenous plexus. The vascular components of internal hemorrhoids drain into the superior rectal vein, which subsequently drains into the inferior mesenteric vein. Band ligation of hemorrhoids cuts off their blood supply, causing them to degenerate. __________ References: Hemorrhoids. (http://www.ncbi.nlm.nih.gov/pubmed/22379400) Hemorrhoids. (http://www.ncbi.nlm.nih.gov/pubmed/21766771)

A 42-Year-Old Man Comes to the Office with Rectal Bleeding