Blood vessels of the rectum and anal canal.

This tutorial covers the anatomy and function of the rectum, focusing on its blood supply and venous drainage. It details the arterial supply from the internal iliac and inferior mesenteric arteries, and the venous drainage through the internal iliac and inferior mesenteric veins. The tutorial also discusses clinical aspects of hemorrhoids, including their causes and treatments.

What are the three main veins that directly drain the rectum?

Describe the venous plexuses associated with the rectum.

What are hemorrhoids and how are they classified?

Discuss the differences between internal and external hemorrhoids.