So the oesophagus and the stomach are really
important in the process of digestion.
The oesophagus, obviously, because
it carries food or bolus
to the stomach from the oral cavity and
then the stomach is going to continue
this process of mechanical
and chemical digestion.
So in this lecture we going to start off by
looking at the surface anatomy,
the position of the oesophagus in the
stomach and then look at
the oesophagus and stomach individually.
Looking at the blood supply and the anatomy
of the oesophagus in the abdomen
and then we going to move on to the stomach and
look into the structure. Talk a little bit
about the gastric ulcers, how they formed.
And also look at the blood and nerve
supply of the stomach.
So if we start off with just nice
key facts about the
oesophagus. While the oesophagus is a
hollow its a muscular tube
and its about 25 cm long, but obviously
this can vary from person
to person and has a diameter of about 2cm.
It’s a muscular tube and it carries out
peristalsis and that means this
contraction of the muscles, muscle fiber
allows the food to pass
down from the pharynx in your throat to the
stomach. To do that it has
to pass through the
through the thorax and it runs
posterior to both the trachea
and the heart. So in your neck the most
anterior you can feel the trachea
and immediately posterior to that you have
the oesophagus and then it
runs directly posterior to the heart.
It then open ups into the stomach,
which is really this muscular expansion
of the gastrointestinal tract. And if you
remember from the surface anatomy, it is located
within the epigastrium and
umbilical region. Sometimes
it extends across into the left
hypochondrium and it stores the ingested
food, the primary function of it.
It also mechanically
churns the ingested food into smaller
fragments that increases the
surface area allowing for
gastric juices to carry out
the chemical digestion.
And ultimately it converts this
ingested bolus of food into
a semi-liquid which is known as Chyme.
This is then expelled
into the rest of the gastrointestinal
tract initially the duodenum,
part of small intestine. As we will
see the stomach can be
divided into numerous regions,
and we'll look at these in more details:
Cardia, Fundus, the Body
and the Pylorus.
So here if we look at the surface
anatomy for the oesophagus and the
stomach. We can see we have got our
clavicles up here and we have got the
the rib cage and we got the ribs
and we have got the mid-line.
And the oesophagus is pretty much runs
down that mid-line towards the
stomach. And to do that it has to
penetrate the diaphragm which you will
see in the moment.And then here we can see
this stomach,tucked down to some of those ribs on
on the left hand side, this kind of
"J" shaped muscular sack
which will then be continous with the
duodenum over in this direction.
We can see that if we super impose these
kinds of cartoons of these images
of these organs onto the person's torso,
we have got a liver here which is
shielding some of the stomach we can see
we got the oesophagus that runs down into
the stomach which we can see here.
And the stomach is going to pass the food into the
"C" shaped duodenum which is the
first initial part of the
small intestine. So we can see the
general layout,the general position
of the oesophagus and the stomach
in these pictures here.