ABDOMINAL AORTA

ABDOMINAL AORTA

ORIGIN AND EXTENT

• The abdominal aorta originates from the descending thoracic aorta at the level of T12 vertebra.
• It extends downwards to the fourth lumbar vertebra.

RELATIONS

• It has a crescentic impression on the left side of the vertebral column.
• On the right side, it is covered by the inferior vena cava, the right kidney, and the right suprarenal gland.
• Behind, it is related to the pancreas, the left kidney, and the splenic vessels.
• In front, it is covered by the peritoneum, the stomach, the left colic flexure, and the small intestine.

BRANCHES

• Coeliac trunk (Truncus coeliacus)
• Superior mesenteric artery
• Inferior mesenteric artery
• Middle suprarenal arteries
• Renal arteries
• Common iliac arteries
• Other branches: Testicular, ovarian, and lumbar arteries

COELIAC TRUNK

COURSE

• The coeliac trunk arises from the abdominal aorta at the level of T12 vertebra, just below the diaphragm.
• It descends downwards and forwards to the left side of the abdominal aorta.
• It then divides into three main branches: Left gastric, common hepatic, and splenic arteries.

DISTRIBUTION

• Left gastric artery: Supplies the stomach.
• Common hepatic artery: Supplies the liver, pancreas, and stomach.
• Splenic artery: Supplies the spleen.

COMMON HEPATIC ARTERY

COURSE

• The common hepatic artery descends downwards and forwards from the coeliac trunk.
• It passes behind the first part of the duodenum and in front of the portal vein.
• It then divides into right and left hepatic arteries.

DISTRIBUTION

• Right hepatic artery: Supplies the right lobe of the liver.
• Left hepatic artery: Supplies the left lobe of the liver.

SPLenic ARTERY

COURSE

• The splenic artery descends downwards and laterally from the coeliac trunk.
• It passes behind the pancreas and in front of the splenic vein.
• It then divides into several branches that supply the spleen.

DISTRIBUTION

• Supplies the spleen, pancreas, and stomach.

COMMON ILLIAC ARTERIES

COURSE

• The common iliac arteries arise from the abdominal aorta at the level of L4 vertebra.
• They descend downwards and forwards to the pelvic cavity.
• Each common iliac artery divides into internal and external iliac arteries.

DISTRIBUTION

• Internal iliac arteries: Supply the pelvic cavity.
• External iliac arteries: Supply the lower limb.

FLOWCHART OF ABDOMINAL AORTA AND ITS BRANCHES

      +---------------+
      |  ABDOMINAL  |
      |  AORTA      |
      +---------------+
              |
              |
              v

+---------------+ +---------------+ | COELIAC | | SUPERIOR | | TRUNK | | MESENTERIC | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | LEFT | | INFERIOR | | GASTRIC | | MESENTERIC | | ARTERY | | ARTERY | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | COMMON | | MIDDLE | | HEPATIC | | SUPRARENAL | | ARTERY | | ARTERIES | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | RIGHT | | RENAL | | HEPATIC | | ARTERIES | | ARTERY | | | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | LEFT | | COMMON | | HEPATIC | | ILLIAC | | ARTERY | | ARTERIES | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | SPLINIC | | TESTICULAR | | ARTERY | | ARTERIES | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | PANCREATIC | | OVARIAN | | ARTERY | | ARTERIES | | ARTERY | | | +---------------+ +---------------+ | | | | v v +---------------+ +---------------+ | GASTRODUOD | | LUMBAR | | DENAL | | ARTERIES | | ARTERY | | | +---------------+ +---------------+