Transverse colon

The transverse colon is the longest and most mobile part part of the large intestine. It measuremeasures up to 45cm45 cm in length. 

Gross pathology and relationsanatomy

The transverse colon is the continuation of the ascending colon from the right colic flexure. It passes from the right to left hypochondrium in a downarddownward convex path crossing both the epigastric and umbilical zones. In the left hypochondrium hypochondrium, it curves sharply on itself beneath the lower end of the spleen, forming the left colic flexure. 

It is almost completely invested by peritoneum, and is connected to the inferior border of the pancreas by a large and wide duplicature of that membrane, the transverse mesocolon. The gastrocolic ligament also attaches the transverse colon to the stomach. 

Relations

• superiorly (right to left) - : liver, gallbladder, greater curvature of the stomach, spleen
• inferiorly: small bowel
• anteriorly - : greater omentum and anterior abdominal wall
• posteriorly (right to left) - 2nd: 2nd part duodenum, head of pancreas, small bowel

Blood supply

• arterial
  • middle colic artery (branch of superior mesenteric artery) supplies proximal 2/3
  • ascending branch of left colic artery (branch of IMA) - supplies distal 1/3
• venous -
  • via similarly named veins to splenic vein to the portal venous system

Nerve supply

• sympathetic
  • superior mesenteric plexus
  • inferior mesenteric plexus
• parasympathetic - derived from pelvic splanchnic nerves (S2-S4)

Lymphatic supplydrainage

Lymphatics accompany vessels and rain to paracolic nodes to the superior mesenteric group (proximal two-thirds) and inferior mesenteric group (distal two-thirds).

Radiological appearanceRadiographic features

Fluoroscopy

Double contrast barium enemas provided good anatomical detail from the rectum to the caecum. The patient may need to be rolled into various positions to get the barium to coat the lumen of the colon.