Colon
Arterial supply of the large intestine
The table below illustrates the main vessels supplying the sections of the large intestine. It should be noted that the junnction of the proximal 2/3 and distal 1/3 of the colon is where the arterial supply switches from superior mesenteric to inferior mesenteric artery.
| Part of large intestine | Main vessel supplying | Origin of vessel |
|---|---|---|
| Appendix & caecum | ileocolic | Superior mesenteric |
| Ascending colon | right colic | Superior mesenteric |
| Transverse | middle colic (left colic supplies distal 1/3) | Superior mesenteric |
| Descending | left colic | Inferior mesenteric |
| Sigmoid | sigmoid branches | Inferior meseteric |
| Rectum | superior rectal branches | inferior mesenteric |
Diagram illustrating arterial supply of the colon
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Diagram illustrating anatomy of the colon
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Anatomical Relations
Ascending colon
| Section of colon | Anterior relations | Posterior relations |
|---|---|---|
| Ascending colon | Loops of small intestine Greater omentum Anterior abdominal wall | Iliacus Iliac crest Quadratus lumborum Transversus abdominis Right kidney (lower pole) Iliohypogastric nerve Ilioinguinal nerve |
| Transverse colon | Greater omentum Anterior abdominal wall | 2nd & 3rd part of duodenum Head of pancreas Loops of small intestine |
| Descending colon | Loops of small intestine Greater omentum Anterior abdominal wall | Iliacus Iliac crest Quadratus lumborum Transversus abdominis Iliohypogastric nerve Ilioinguinal nerve Left kidney (lower pole) |
| Sigmoid colon | Bladder Uterus & upper vagina | Rectum Sacrum Loops of small bowel |