00:00
Your main anatomical question will be
related to the angle of Louis. So this is
your angle of Louis. That corresponds to the
lower border of a T4 vertebra and the second
intercostal space. I think you had a question
in your pre-course assessment, the important
structures. You read your answers, but you should
know this. What are the important structures?
What are the important anatomical points?
So if you see a CT scan at this point, what
are the things you need to look for?
Bifurcation of the trachea?
Arch of the aorta. Arch of the aorta, so
the ascending. The
arch of the aorta. So the end of the ascending
aorta and it’s the start of the descending
aorta. So that’s there. What else?
Azygous vein enters --
Azygous vein enters mostly the SVC at that
level, to the superior vena cava. The superior
vena cava enters the right atrium at that
level. Anything else? Imagine you are seeing
a CT section and you’ve seen the T4 vertebra,
what else would you expect to see? The thoracic
duct. Thoracic duct crosses over from the
right to the left at that level. And this
is anatomical plane for the superior mediastinum.
Superior mediastinum is above this, and
the inferior mediastinum is below this. Even
though you don’t have to know the anatomy
of the heart for the part A, I just quickly
draw it so that the rest of it will make sense
to you. So, third intercostal space here,
sixth intercostal
space there, second and apex. So this is the
surface anatomy of the heart. So three, six,
two, and five, that’s the heart. Then you
have the arch of aorta. It divides into
left subclavian, left common carotid, and
the brachiocephalic trunk. Brachiocephalic
trunk divides into common carotid and subclavian.
From the brachiocephalic, can you think of
any branches from the brachiocephalic trunk?
Anterior intercostal?
Anterior?
Intercostal.
02:47
Not from the brachiocephalic. The only thing
you can think of the brachiocephalic from
the arch is your thyroid ima artery. It’s very,
very small artery. There’s nothing significant.
02:58
They’re not from brachiocephalic. They’re
from the subclavian. You have the internal
carotid going there. So if we can forget
about it. So, subclavian, what are branches
of the subclavian artery?
Vertebral.
03:12
Vertebral.
Internal thoracic.
03:14
Internal thoracic.
Costo --
Costocervical trunk, very good, yeah. Very
good. You’re almost there. Fine.
03:24
I’ll do that. So, the common carotid is coming up,
external carotid, internal carotid. We discussed this.
03:36
So we leave that one side. So this is the subclavian.
The subclavian artery, that’s the scalene