Inferior mesenteric artery Flashcards
what is the IMA a major branch of?
a major branch of the abdominal aorta
what does the IMA supply?
arterial blood to the organs of the hindgut - the distal 1/3 of the transverse colon, splenic flexure, descending colon, sigmoid colon and rectum
where does the inferior mesenteric artery stem from?
The IMA is the last of the three major anterior branches of the abdominal aorta
aside from the IMA, what are the 2 other branches of the abdominal aorta?
coeliac trunk and superior mesenteric artery
where does the IMA arise from?
It arises at L3, near the inferior border of the duodenum, 3-4 cm above where the aorta bifurcates into the common iliac arteries
as the IMA arises from the aorta, where does it descend?
it descends anteriorly to its parent vessel, before moving to the left side
what type of structure is the IMA? where is it situated?
It is a retroperitoneal structure – situated behind the peritoneum
what do the branches of the IMA supply?
structures of the embryonic hindgut. These include the distal 1/3 of the transverse colon, splenic flexure, descending colon, sigmoid colon and rectum
how many major branches arise from the IMA and what are they?
3
left colic artery, sigmoid artery and superior rectal artery
what is the first branch of the IMA?
The left colic artery
what does the left colic artery supply?
It supplies the distal 1/3 of the transverse colon and the descending colon
arising from the parent artery, where does the left colic artery travel?
it travels anteriorly to the psoas major muscle, left ureter and left internal spermatic vessels
what happens after the left colic artery has travelled to the left internal spermatic vessel?
it divides into ascending and descending branches
what is the course of travel of the ascending branch of the left colic artery?
crosses the left kidney anteriorly, before entering the mesentery of the transverse colon, moving superiorly
what does the ascending branch of the left colic artery supply?
the distal 1/3 of the transverse colon, and the upper aspect of the descending colon
where does the descending branch of the left colic artery travel? what does it supply?
moves inferiorly to supply the lower part of the descending colon. It anastamoses with the superior sigmoid artery
what does the descending branch of the left colic artery anastomose with?
superior sigmoid artery
what do the sigmoid arteries supply?
supply the descending colon and the sigmoid colon
how many branches are there typically to the sigmoid arteries?
typically 2-4 branches
what is the uppermost branch of the sigmoid artery termed?
the superior sigmoid artery