Blood Vessels of the Abdomen
and Pelvis Arterial Supply of the
Abdomen The Abdominal Aorta This is obviously the continuation of the thoracic aorta. It begins at the aortic hiatus in the diaphragm at the level of the intervertebral disc between T12 and L1. It ends around the level of L4 vertebra by dividing into two common iliac arteries. Throughout its course, it lies against the vertebral bodies. Relations of the Abdominal Aorta Anteriorly, the abdominal aorta is related to: 1. The coeliac trunk and its branches; 2. The coeliac plexus; 3. The omental bursa; 4. The pancreas; 5. The left renal vein; 6. The ascending part of the duodenum; 7. The root of the mesentery; 8. And the intermesenteric plexus of nerves. Posteriorly, the abdominal aorta descends anterior to: 1. The bodies of L1 to L4 vertebrae; 2. The intervening intervertebral discs; 3. And the corresponding part of the anterior longitudinal ligament. On the right, of the abdominal aorta is the IVC. Related superiorly to the abdominal aorta on the right is: 1. The cisterna chyli; 2. The thoracic duct; 3. And the right crus of the diaphragm. On the left, the abdominal aorta is related superiorly to the left crus of the diaphragm and the left coeliac ganglion. The duodenojejunal flexure is on its left, opposite L2 vertebra. The sympathetic trunk runs along its left side. Back to top Surface Anatomy of the Abdominal
Aorta This is represented by a broad band
(about 2 cm wide), extending from a median point, about 2.5 cm superior to the transpyloric plane, to a point slightly inferior and to the left of the umbilicus. The latter point represents the level of bifurcation of the aorta to the common iliac arteries. The aortic bifurcation is just to the left of the midpoint of the line joining the highest points of the iliac crests. Branches of the Abdominal Aorta (from
Ashwell) Ventral Branches (unpaired) Click here to go to the ventral branches. 1. Coeliac trunk 2. Superior mesenteric artery 3. Inferior mesenteric artery Lateral (paired) Click here to go to the lateral branches. 1. Inferior phrenic 2. Middle suprarenal 3. Renal 4. Gonadal (ovarian or testicular) Posterior (paired and unpaired) Click here to go to the posterior branches. 1. Lumbar (paired) 2. Median sacral (unpaired) Terminal (paired) 1. Common iliac Back to top Ventral Branches There are anastomoses between these
arteries and with their branches. 1. Left gastric artery branches with the aortic oesophageal branches around the lower oesophagus. 2. Anterior and posterior superior pancreaticoduodenal arteries (coeliac trunk) with the inferior pancreaticoduodenal (superior mesenteric branch) around the head of the pancreas and 2nd part of the duodenum. 3. The marginal artery anastomosis between the middle colic and the left colic. 4. The superior rectal artery (inferior mesenteric) with the middle rectal (internal iliac) and/or the inferior rectal (internal pudendal from internal iliac). Back to top Lateral Branches Inferior Phrenic Artery These are two small arteries that help supply the diaphragm and some small parts of the spleen and liver. They arise separately, as a common trunk
or from the coeliac trunk. Each artery ascends anterior to the crus of the diaphragm medial to the suprarenal gland. These arteries anastomose with the musculophrenic, posterior intercostal, and pericardiacophrenic arteries. They give off the superior suprarenal arteries. Middle Suprarenal Artery These arise level with the superior mesenteric artery. The right passes behind the IVC. Both are related to the coeliac ganglion of the respective sides. These anastomose with the suprarenal branches of the inferior phrenic and renal arteries. Renal Artery These two larger arteries branch from the
aorta, just inferior to the level of the superior mesenteric artery. The right is longer and passes posterior to the IVC, right renal vein, body of the pancreas and descending part of the duodenum. The left passes posterior to the left renal vein, body of the pancreas and splenic vein. Each of these divides into 4 or 5 branches. Each renal artery gives off an inferior suprarenal branch and supplies the ureter in its upper extent. Testicular Artery These two arise anteriorly from the aorta, slightly inferior to the renal artery. Each passes anterior to the psoas major behind the parietal peritoneum. They then pass to the deep inguinal ring and enter the spermatic cord, finally passing into the scrotum. The testicular artery supplies the testis, perirenal fat, ureter, iliac lymph nodes and cremaster. Ovarian Artery These correspond to the testicular
arteries but are obviously in the female. They enter the pelvis to supply the ovaries. After entering the suspensory ligament of the ovary, they continue into the broad ligament of the uterus. Branches are given off to the ovary, ureter, uterine tubes and one branch passes to the side of the uterus to
anastomose with the uterine artery. Other branches follow the round ligament of the uterus to the inguinal ligament and supply the skin of the
labium majus. Back to top Dorsal Branches Lumbar Arteries There are usually 4 on each side. These pass anterior to the 4 upper lumbar vertebral bodies, pass behind the sympathetic trunks to the posterior abdominal wall. The right arteries pass posterior to the IVC. The branches of each artery include: 1. Spinal (to the vertebral canal and
contents) 2. Ventral (to body wall) 3. Dorsal (to dorsal muscles, joints and skin) Median Sacral Artery This is a small posterior branch. It leaves the aorta slightly above its
bifurcation and descends anterior to the midline of L4, L5, the sacrum and ends in the coccyx. Back to top Terminal Branches of the Abdominal
Aorta The abdominal aorta bifurcates anterior to the left side of L4 into the common iliac arteries. These two arteries diverge and further
divide into the internal and external iliac arteries on each side at the level of the lumbosacral intervertebral disc. The external iliac artery gives off the inferior epigastric and deep circumflex iliac arteries and continues as the femoral artery in the lower limb. The internal iliac artery gives many branches and these are divided into anterior and posterior trunk divisions. Branches of the External Iliac Artery Inferior Epigastric Artery This arises from the external iliac just
proximal to the inguinal ligament. It ascends medial to the deep inguinal ring (raising the parietal peritoneum as it does so to form the lateral umbilical fold). It then pierces the transversalis fascia passing anterior the posterior layer of the rectus sheath. It divides into numerous branches, some
of which anastomose with the superior epigastric and posterior intercostal arteries. Deep Circumflex Iliac Artery This arises almost opposite the inferior epigastric artery. It ascends the iliac crest anastomosing with the ascending branches of the lateral circumflex femoral, lumbar and inferior epigastric arteries. Back to top Branches from the Anterior Trunk of
Internal Iliac Artery The superior vesical artery with several branches. It was derived from the umbilical artery of the foetus. The inferior vesical artery (in males). The middle rectal artery. The uterine artery (in females). The vaginal artery (corresponds to the inferior vesical artery of males). The obturator artery. This leaves to the pelvis via the obturator foramen. The internal pudendal artery. This leaves the pelvis between the piriformis and coccygeus muscles. It passes deep to the sacrotuberous ligament to enter the pudendal canal in the lateral wall of the ischiorectal fossa. The artery has several branches including
the inferior rectal artery. The inferior gluteal artery. This leaves the pelvis below the piriformis muscle through the greater sciatic foramen. Branches of the Posterior Trunk of the
Internal Iliac Artery The iliolumbar trunk ascends to the medial border of the psoas major muscle. The lateral sacral arteries. The superior gluteal artery. This leaves the greater sciatic foramen above the piriformis muscle. Back to top Venous Drainage of the
Abdomen There is general portal circulation for the intraperitoneal part. In contrast, there are systemic veins for the extraperitoneal part. Portal Circulation The Portal Vein The portal vein is about 8 cm long and valveless, as are its tributaries, in adult life. It begins at the level of L2 by the junction of the splenic and superior mesenteric veins. As it reaches the porta hepatis it divides into left and right branches, which supplies the corresponding halves of the
liver. The right branch supplies the right half of the liver and usually receives the cystic vein. The left branch divides into branches to the caudate, quadrate and left lobes. As the left branch enters the living, it is
joined by paraumbilical veins, the ligamentum teres and is connected to the IVC by the ligamentum venosum. The tributaries of the portal vein are the splenic, superior mesenteric, left gastric, right gastric, paraumbilical and cystic veins. Tributaries of the Splenic Vein 1. Short gastric vein 2. Left gastro-omental (gastroepiploic) vein 3. Pancreatic veins 4. Inferior mesenteric (receives the left
colic and sigmoid veins) Tributaries of the Superior Mesenteric
Vein 1. Right gastro-omental (gastroepiploic)
vein 2. Pancreaticoduodenal vein 3. Jejunal and ileal veins 4. Ileocolic vein 5. Right colic vein 6. Middle colic vein Back to top Portal-Systemic Anastomoses Site Portal
Tributaries Systemic
Tributaries Oesophagus Left gastric
oesophageal
branches Oesophageal
branches to azygos, accessory
hemiazygos
veins Umbilicus Ligamentum
teres veins (paraumbilical
veins) Epigastric veins Anal canal Superior rectal
veins Middle and
inferior rectal
veins Retroperitoneal Venous radicles
of colon and bare area of liver Retroperitoneal
veins Liver Patent ductus
venosus (branch
of left portal
vein branch) IVC Back to top Systemic Veins This consists of the inferior vena cava and its tributaries in the abdomen. Lumbar Veins There are 4 pairs of these draining the lumbar region and posterior abdominal wall. Near the vertebral column, they drain the vertebral venous plexus and are connected by the ascending lumbar veins to the common iliac and iliolumbar veins. Testicular Veins These drain the epididymis and testis. They unite to form the pampiniform plexus and ascend with the testicular artery. The right one enters the IVC just below the renal veins. The left one enters the left renal vein. Ovarian Veins These arise from a plexus in the broad ligament to ascend with the ovarian artery much like the testicular veins. Hepatic Veins These enter the IVC as it passes through the superior aspect of the liver. Other Veins The renal veins. The suprarenal veins. The inferior phrenic veins. Blood Vessels of the Abdomen
and Pelvis Arterial Supply of the
Abdomen The Abdominal Aorta This is obviously the continuation of the thoracic aorta. It begins at the aortic hiatus in the diaphragm at the level of the intervertebral disc between T12 and L1. It ends around the level of L4 vertebra by dividing into two common iliac arteries. Throughout its course, it lies against the vertebral bodies. Relations of the Abdominal Aorta Anteriorly, the abdominal aorta is related to: 1. The coeliac trunk and its branches; 2. The coeliac plexus; 3. The omental bursa; 4. The pancreas; 5. The left renal vein; 6. The ascending part of the duodenum; 7. The root of the mesentery; 8. And the intermesenteric plexus of nerves. Posteriorly, the abdominal aorta descends anterior to: 1. The bodies of L1 to L4 vertebrae; 2. The intervening intervertebral discs; 3. And the corresponding part of the anterior longitudinal ligament. On the right, of the abdominal aorta is the IVC. Related superiorly to the abdominal aorta on the right is: 1. The cisterna chyli; 2. The thoracic duct; 3. And the right crus of the diaphragm. On the left, the abdominal aorta is related superiorly to the left crus of the diaphragm and the left coeliac ganglion. The duodenojejunal flexure is on its left, opposite L2 vertebra. The sympathetic trunk runs along its left side. Back to top Surface Anatomy of the Abdominal
Aorta This is represented by a broad band
(about 2 cm wide), extending from a median point, about 2.5 cm superior to the transpyloric plane, to a point slightly inferior and to the left of the umbilicus. The latter point represents the level of bifurcation of the aorta to the common iliac arteries. The aortic bifurcation is just to the left of the midpoint of the line joining the highest points of the iliac crests. Branches of the Abdominal Aorta (from
Ashwell) Ventral Branches (unpaired) Click here to go to the ventral branches. 1. Coeliac trunk 2. Superior mesenteric artery 3. Inferior mesenteric artery Lateral (paired) Click here to go to the lateral branches. 1. Inferior phrenic 2. Middle suprarenal 3. Renal 4. Gonadal (ovarian or testicular) Posterior (paired and unpaired) Click here to go to the posterior branches. 1. Lumbar (paired) 2. Median sacral (unpaired) Terminal (paired) 1. Common iliac Back to top Ventral Branches There are anastomoses between these
arteries and with their branches. 1. Left gastric artery branches with the aortic oesophageal branches around the lower oesophagus. 2. Anterior and posterior superior pancreaticoduodenal arteries (coeliac trunk) with the inferior pancreaticoduodenal (superior mesenteric branch) around the head of the pancreas and 2nd part of the duodenum. 3. The marginal artery anastomosis between the middle colic and the left colic. 4. The superior rectal artery (inferior mesenteric) with the middle rectal (internal iliac) and/or the inferior rectal (internal pudendal from internal iliac). Back to top Lateral Branches Inferior Phrenic Artery These are two small arteries that help supply the diaphragm and some small parts of the spleen and liver. They arise separately, as a common trunk
or from the coeliac trunk. Each artery ascends anterior to the crus of the diaphragm medial to the suprarenal gland. These arteries anastomose with the musculophrenic, posterior intercostal, and pericardiacophrenic arteries. They give off the superior suprarenal arteries. Middle Suprarenal Artery These arise level with the superior mesenteric artery. The right passes behind the IVC. Both are related to the coeliac ganglion of the respective sides. These anastomose with the suprarenal branches of the inferior phrenic and renal arteries. Renal Artery These two larger arteries branch from the
aorta, just inferior to the level of the superior mesenteric artery. The right is longer and passes posterior to the IVC, right renal vein, body of the pancreas and descending part of the duodenum. The left passes posterior to the left renal vein, body of the pancreas and splenic vein. Each of these divides into 4 or 5 branches. Each renal artery gives off an inferior suprarenal branch and supplies the ureter in its upper extent. Testicular Artery These two arise anteriorly from the aorta, slightly inferior to the renal artery. Each passes anterior to the psoas major behind the parietal peritoneum. They then pass to the deep inguinal ring and enter the spermatic cord, finally passing into the scrotum. The testicular artery supplies the testis, perirenal fat, ureter, iliac lymph nodes and cremaster. Ovarian Artery These correspond to the testicular
arteries but are obviously in the female. They enter the pelvis to supply the ovaries. After entering the suspensory ligament of the ovary, they continue into the broad ligament of the uterus. Branches are given off to the ovary, ureter, uterine tubes and one branch passes to the side of the uterus to
anastomose with the uterine artery. Other branches follow the round ligament of the uterus to the inguinal ligament and supply the skin of the
labium majus. Back to top Dorsal Branches Lumbar Arteries There are usually 4 on each side. These pass anterior to the 4 upper lumbar vertebral bodies, pass behind the sympathetic trunks to the posterior abdominal wall. The right arteries pass posterior to the IVC. The branches of each artery include: 1. Spinal (to the vertebral canal and
contents) 2. Ventral (to body wall) 3. Dorsal (to dorsal muscles, joints and skin) Median Sacral Artery This is a small posterior branch. It leaves the aorta slightly above its
bifurcation and descends anterior to the midline of L4, L5, the sacrum and ends in the coccyx. Back to top Terminal Branches of the Abdominal
Aorta The abdominal aorta bifurcates anterior to the left side of L4 into the common iliac arteries. These two arteries diverge and further
divide into the internal and external iliac arteries on each side at the level of the lumbosacral intervertebral disc. The external iliac artery gives off the inferior epigastric and deep circumflex iliac arteries and continues as the femoral artery in the lower limb. The internal iliac artery gives many branches and these are divided into anterior and posterior trunk divisions. Branches of the External Iliac Artery Inferior Epigastric Artery This arises from the external iliac just
proximal to the inguinal ligament. It ascends medial to the deep inguinal ring (raising the parietal peritoneum as it does so to form the lateral umbilical fold). It then pierces the transversalis fascia passing anterior the posterior layer of the rectus sheath. It divides into numerous branches, some
of which anastomose with the superior epigastric and posterior intercostal arteries. Deep Circumflex Iliac Artery This arises almost opposite the inferior epigastric artery. It ascends the iliac crest anastomosing with the ascending branches of the lateral circumflex femoral, lumbar and inferior epigastric arteries. Back to top Branches from the Anterior Trunk of
Internal Iliac Artery The superior vesical artery with several branches. It was derived from the umbilical artery of the foetus. The inferior vesical artery (in males). The middle rectal artery. The uterine artery (in females). The vaginal artery (corresponds to the inferior vesical artery of males). The obturator artery. This leaves to the pelvis via the obturator foramen. The internal pudendal artery. This leaves the pelvis between the piriformis and coccygeus muscles. It passes deep to the sacrotuberous ligament to enter the pudendal canal in the lateral wall of the ischiorectal fossa. The artery has several branches including
the inferior rectal artery. The inferior gluteal artery. This leaves the pelvis below the piriformis muscle through the greater sciatic foramen. Branches of the Posterior Trunk of the
Internal Iliac Artery The iliolumbar trunk ascends to the medial border of the psoas major muscle. The lateral sacral arteries. The superior gluteal artery. This leaves the greater sciatic foramen above the piriformis muscle. Back to top Venous Drainage of the
Abdomen There is general portal circulation for the intraperitoneal part. In contrast, there are systemic veins for the extraperitoneal part. Portal Circulation The Portal Vein The portal vein is about 8 cm long and valveless, as are its tributaries, in adult life. It begins at the level of L2 by the junction of the splenic and superior mesenteric veins. As it reaches the porta hepatis it divides into left and right branches, which supplies the corresponding halves of the
liver. The right branch supplies the right half of the liver and usually receives the cystic vein. The left branch divides into branches to the caudate, quadrate and left lobes. As the left branch enters the living, it is
joined by paraumbilical veins, the ligamentum teres and is connected to the IVC by the ligamentum venosum. The tributaries of the portal vein are the splenic, superior mesenteric, left gastric, right gastric, paraumbilical and cystic veins. Tributaries of the Splenic Vein 1. Short gastric vein 2. Left gastro-omental (gastroepiploic) vein 3. Pancreatic veins 4. Inferior mesenteric (receives the left
colic and sigmoid veins) Tributaries of the Superior Mesenteric
Vein 1. Right gastro-omental (gastroepiploic)
vein 2. Pancreaticoduodenal vein 3. Jejunal and ileal veins 4. Ileocolic vein 5. Right colic vein 6. Middle colic vein Back to top Portal-Systemic Anastomoses Site Portal
Tributaries Systemic
Tributaries Oesophagus Left gastric
oesophageal
branches Oesophageal
branches to azygos, accessory
hemiazygos
veins Umbilicus Ligamentum
teres veins (paraumbilical
veins) Epigastric veins Anal canal Superior rectal
veins Middle and
inferior rectal
veins Retroperitoneal Venous radicles
of colon and bare area of liver Retroperitoneal
veins Liver Patent ductus
venosus (branch
of left portal
vein branch) IVC Back to top Systemic Veins This consists of the inferior vena cava and its tributaries in the abdomen. Lumbar Veins There are 4 pairs of these draining the lumbar region and posterior abdominal wall. Near the vertebral column, they drain the vertebral venous plexus and are connected by the ascending lumbar veins to the common iliac and iliolumbar veins. Testicular Veins These drain the epididymis and testis. They unite to form the pampiniform plexus and ascend with the testicular artery. The right one enters the IVC just below the renal veins. The left one enters the left renal vein. Ovarian Veins These arise from a plexus in the broad ligament to ascend with the ovarian artery much like the testicular veins. Hepatic Veins These enter the IVC as it passes through the superior aspect of the liver. Other Veins The renal veins. The suprarenal veins. The inferior phrenic veins.
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