Ascending Colon

Ascending colon is the first part of colon, the second part of large intestine. It is about 5 inches in length and lies in the right lower quadrant of trunk. It extends from the cecum, upward to the inferior surface of right lobe of liver. At this position, it turns left to form the right colic flexure and becomes continuous with the transverse colon.

The peritoneum covers the front and the sides of the ascending colon and binds it to the posterior abdominal wall.

Relations of ascending colon:

Anterior relations:

  • Coils of small intestine
  • Greater omentum
  • Anterior abdominal wall

Posterior relations:

  • Iliacus muscle
  • Iliac crest
  • Quadratus lumborum muscle
  • Origin of transversus abdominis muscle
  • Lower aspect of the right kidney
  • Iliohypogastric and ilioinguinal nerves

Blood supply of ascending colon:

Arteries:

The ascending colon receives its blood supply from the ileocolic and right colic branches of the superior mesenteric artery.

Veins:

The veins correspond to the arteries and eventually drain into the superior mesenteric vein.

Lymph drainage:

The lymph vessels drain into lymph nodes lying along the course of the blood vessels of the ascending colon. Ultimately the lymph reaches the superior mesenteric lymph nodes.

Nerve supply to ascending colon:

The ascending colon receives the sympathetic and parasympathetic nerves from the superior mesenteric plexus.