Superior Mesenteric Artery

Question 1

Origin

Answer 1

From front of abdominal aorta opposite 1st lumbar vertebra lower border (about 1cm below coeliac trunk)

Question 2

Course

Answer 2

1. Lies behind pancreas body between two veins (splenic vein (above artery origin) and left renal vein (below artery origin))
2. Descends in front of pancreas uncinate process and duodenum 3rd part
3. Enter root of small intestine mesentery
4. In mesentery, it runs downwards and to right (with superior mesenteric vein on its right) crossing over 6 structures
5. Surrounded by superior mesenteric plexus of nerves throughout its course

Question 3

Structures crossed over

Answer 3

1. Abdominal artery
2. IVC
3. Right Psoas major
4. Right ureter
5. Right gonadal vessels
6. Right genitofemoral nerve

Question 4

Termination

Answer 4

At ileocaecal junction by anastomosing with ileocolic branch

Question 5

Branches

Answer 5

1. Middle colic
2. Inferior pancreatico-duodenal
3. Right colic
4. Ileocolic
5. Jejunal
6. Ileal

Question 6

Middle colic site

Answer 6

Arises just below pancreas and runs in transverse mesocolon dividing into right and left branches

Question 7

Right branch

Answer 7

Anastomoses with ascending branch of right colic artery

Question 8

Left branch

Answer 8

Anastomoses with ascending branch of superior left colic artery

Question 9

Supply

Answer 9

Middle 1/3 of transverse colon

Question 10

Inferior pancreatico-duodenal site and course

Answer 10

1. Arises as it crosses uncinate process
2. Runs in groove between pancreas head and duodenum
3. End by anastomosing with superior pancreaticoduodenal artery (from hepatic artery)

Question 11

Inferior pancreaticoduodenal supply

Answer 11

1. Duodenum lower 1/2
2. Lower 1/2 of pancreas head and its uncinate process

Question 12

Right colic course

Answer 12

1. Arises from the artery concave right side at its middle
2. Runs to right retroperitonealy towards ascending colon
3. Crosses 3 structures
4. Ends by dividing into ascending and descending branches

Question 13

Right colic crossed structures with

Answer 13

1. Right gonadal vessels
2. Right ureter
3. Right Psoas major

Question 14

Ascending branch right colic

Answer 14

Anastomoses with right branch of middle colic artery

Question 15

Descending branch right colic

Answer 15

Anastomoses with ascending branch of ileocolic artery

Question 16

Right colic supply

Answer 16

1. Upper 2/3 of ascending colon
2. Right colic flexure

Question 17

Jejunal and Ileal

Answer 17

1. 12-15 branches arise from the artery convex left side
2. Run between 2 layers of small intestine mesentery
3. Divide repeatedly forming arches (arterial arcades) which give straight end arteries (vasa recta)
4. Jejunal branches are longer and less numerous their arcades are fewer than Ileal branches

Question 18

Ileocolic course

Answer 18

1. Arises from lower part of the artery concave right side
2. Runs to right retroperitonealy towards right iliac fossa
3. End by dividing into ascending and descending branches

Question 19

Ascending branch ileocolic

Answer 19

Anastomoses with right colic artery

Question 20

Descending branch ileocolic

Answer 20

Runs towards ileocaecal junction to anastomose with superior mesenteric artery termination

Question 21

Descending branch ileocolic branches

Answer 21

1. Ascending branch
2. Anterior and posterior Caecal artery
3. Appendicular artery
4. Ileal branch

Question 22

Ascending branch of descending branch supply

Answer 22

To ascending colon lower 1/3

Question 23

Anterior and posterior Caecal arteries supply

Answer 23

To caecum front and back

Question 24

Appendicular artery course

Answer 24

Descends behind ileum termination to enter mesoappendix

Question 25

Appendicular artery supply

Answer 25

Appendix

Question 26

Ileal branch supply

Answer 26

Ileum terminal part