Now let's move on to the superior mesenteric artery.
Superior mesenteric artery supplying the midgut.
The midgut going from the distal half of the duodenum,
so all structures distal to the major duodenal papilla.
And it includes the jejunum, the ileum,
the caecum (appendix), ascending colon
and the proximal 2/3rd of the transverse colon.
And we can see
the superior mesenteric artery here,
around about L1, is giving rise to a
series of jejunal arteries and ileal arteries that
pass within the mesentery towards the jejunum and the ileum.
It carries on in this direction
alongside the roots of the mesentery
and passes to the lower right quadrant.
As it approaches the lower right quadrant
it then gives rise to ileocolic arteries.
Ileocolic arteries that go and supply the appendix.
And also a right colic artery
and a middle colic artery
The middle colic artery is important because that
passes up and that contributes to this marginal artery,
which we will come back to in a moment.
And that runs along the inside of the
transverse colon. And these colic arteries
feed into it, the middle colic, specifically.
We also have the inferior
pancreaticoduodenal artery. And we spoke
about that when we looked at the
arterial supply to the foregut.
So we have got superior mesenteric artery, gives branches
to the jejunum, gives branches to the ileum.
It gives branches to the ileocolic junction, so
to the distal part of the ileum, to the caecum
and we will also find it up the appendicular branch
there as well. We then have a right colic artery
and we have a middle colic artery.
And these will give branches to the
marginal artery. And this runs
along the inside parallely
most of the transverse colon and then it drifts
down, as we see, the inferior mesentery artery
into the descending colon. And we have got the
inferior pancreaticoduodenal that we have spoken about.
So the midgut extending from the
distal half of the duodenum to the
proximal 2/3rd of the transverse colon. That stretch of
the GI tract is supplied by superior mesenteric.