 Good day everybody. This is going to be a demonstration of the entire ease of figures and the company Vegas. This is a supine cadaver I'm standing on the right side camera person is also on the right side So the extent of the ease of figures is from the neck to the abdomen The cervical ease of figures is approximately from this level where my instrument is pointing to T1 So that is a cervical ease of figures Then if I were to lift up this then we have the thoracic ease of figures Thoracic ease of figures is from T1 to T10 To T1 is a thoracic inlet T10 is the ease of a gel hiatus in the diaphragm It is running in the posterior medias channel and then we have the prominence of figures Which is a very short segment, but we have pulled it down to make it look a little big It is from T10 to T11 Initially the ease of figures is situated a little on the right side and we can see it is located to the Right of the descending thoracic aorta But as it goes down at the level of diaphragm It moves a little in front of the aorta and it moves to the left and we can see the aorta is moving to the back So it moves to the left and this is where it exits through the isophageal hiatus So therefore abdominal segment of these are figures is from T10 to T11 This is only just half an inch apart from that There are a few other points the cervical portion of these are figures and thoracic part of these are figures does not have any Serosal covering so therefore there is no protection While the abdominal part of the ease of figures is encircled by visceral baritoneum, which is referred to as the serosa Now we come to the sites of isophageal constrictions. The first constriction is at its origin itself And that is referred to as the upper isophageal sphincter or the pharyngo isophageal junction This constriction is produced by a muscle called the cricopharyngeus muscle Which is the muscle of the pharynx and that constitutes the upper isophageal sphincter This constriction is approximately 15 centimeter from the incisor teeth as seen through an isophageal scope The next constriction is at this complex that we can see here. We can see this is the arch of the aorta The arch of the aorta as it goes it curves posteriorly and behind and therefore it compresses the isophagus from the side And we can see it here. It compresses the isophagus on the side here So this is another constriction and closely happening that constriction is this constriction produced by the bifurcation of the trachea Into the left and the right principal promise So these two constrictions together are considered to be approximately at the level of 25 centimeters from the incisor teeth Aortic arch constriction is from the sides. Therefore it is best seen in an anterior posterior view While the tracheal bifurcation constriction is moved from anterior posterior So therefore this best seen in a lateral view of a barium swallow This is a barium swallow to show the aortic arch and the left main bronchus constriction of the isophagus And the third constriction is at the isophageal hiatus Which is at the level of 40 centimeters from the incisor teeth and this constriction is produced by This structure of the diaphragm Now if you were to look closely we can see this muscle fibers that we see here This is the right cross of the diaphragm The right cross of the diaphragm as it goes it completely encircles the isophagus and it comes back again This constitutes the lower isophageal sphincter and this constitutes the Lowest constriction for the diaphragmatic constriction This is another barium swallow to show diaphragmatic constriction and a dilatation above that called the phrenic ampulla So we have seen the two sphincters and we have seen the constrictions Now let's take a look at the blood supply and the venous drainage The blood supply of the cervical to the isophagus is the inferior thyroid artery This is the thyroid and the inferior thyroid artery is a branch of the subclavian artery The venous drainage is to the inferior thyroid vein which drains into the brachiosophalic vein The thoracic part of the isophagus the blood supply is from the Descending thoracic aorta the isophageal branches and the venous drainage is to this vein here This is the azagus vein So this is also part of the systolic circulation because it drains into the supia venaigiva The abdominal part of the isophagus gets a blood supply totally different This is the celiac trunk and we can see these branches This is the left gastric artery And the isophageal branch of the left gastric artery supplies the abdominal part of the isophagus And the venous drainage is to the left gastric vein which drains into the portal vein So therefore we have a very important clinical correlation here The abdominal part of the isophagus belongs to the portal circulation The rest of the isophagus belongs to the systemic circulation So in the sub-bucosa of the isophagus at the lower end, there are small microscopic communications Which is not visible in a normal person And those communications are referred to as the porta systemic communications In a patient with alcoholic cirrhosis and portal hypertension These porta systemic communications become dilated And then they become known as isophageal varices Which we can see through an endoscope and these can rupture and they can lead to life-threatening hematomases This is a distinction specimen from another cadaver to show alcoholic material cirrhosis of the liver And this is an isophagoscopic view to nominate the isophagus to show isophageal varices, which I described just now The next point which I want to mention to you was about the nerve supply of the isophagus We have seen this nerve here and we can see this nerve here This is the right vagus and we can see the right vagus is coming down from the neck And it is going in front of the subclavian artery and is entering into the thorax It is going behind the column of the lung Similarly the left vagus, this is the left vagus And we can see it is coming in the carotid sheath It goes behind the column of the left lung And below the column it breaks up into a plexus And we have removed most of the plexus, but we can see some of the fibres of the plexus here And after that the left vagus comes anterior and we can see that here It is curving anteriorly And the right vagus goes posterior and we can see it is going posterior And both of them exit the thorax through the same hiatus. That's the isophageal hiatus The left vagus or the anterior vagus is the smaller one It supplies only the anterior part of the stomach And it supplies the hepatic and the biliary plexus The right vagus, the posterior vagus is the larger one and it supplies up to the neck Cervical isophagus and the thoracic isophagus The cervical isophagus drains into the lower deep cervical nodes And the thoracic isophagus, it drains into the stereometastinal nodes While the abdominal isophagus, it drains into the celiac nodes Cancer of the thoracic isophagus and the cervical isophagus, they tend to spread very rapidly Because there is no cirrhosis covering And therefore cancer of the isophagus is very difficult to treat And the life expectancy and the prognosis is very poor The best way to study the isophagus is by means of a barium swallow Followed by isophagoscopy Another gold standard test for the isophagus is isophageal pressure recording Which is referred to as isophageal manometry Which is required in mortality disorders, which I will describe just now And because there is no cirrhosis covering in the thoracic part of the isophagus While doing an isophagoscopy, rupture of the isophagus And various units is a likely possibility And finally some other pathologies pertaining to the isophagus Sometimes there may be a mismatch in the peristaltic constrictions of the isophagus And that can lead to dysphagia One such condition is referred to as press by isophagus And the other is what is known as diffuse isophageal spasm They are all because of abnormalities of the parasympathetic supply of the isophagus So these are some of the points which I wanted to mention to you about the isophagus And the vagus nerve in the cervical region, thoracic region and the abdominal region