 Good day everybody. This is going to be a demonstration of the entire ease of Vegas 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 Vegas is approximately from this level where my instrument is pointing to T1 So that is a cervical ease of Vegas Then if I were to lift up this then we have the thoracic ease of Vegas Thoracic ease of Vegas is from T1 to T10 To T1 is the thoracic inlet T10 is the ease of agile hiatus in the diaphragm It is running in the posterior medial sternum and then we have the abdominal ease of Vegas 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 Vegas 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 exists through the ease of vigil hiatus So therefore abdominal segment of ease of Vegas 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 the ease of Vegas and thoracic part of ease of Vegas does not have any serosal covering So therefore there is no protection While the abdominal part of the ease of Vegas is encircled by visceral baritoneum, which is referred to as the serosa Now we come to the sites of ease of vigil constrictions The first constriction is at its origin itself And that is referred to as the upper ease of vigil sphincter or the pharyngeal ease of vigil junction This constriction is produced by a muscle called the cricopharyngeus muscle Which is the muscle of the pharynx and that constitutes the upper ease of vigil sphincter This constriction is approximately 15 centimeter from the incisor teeth as seen through an ease of vigil 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 ease of vigil from the side And we can see it here. It compresses the ease of vigil on the side here So this is another constriction and closely accompanying that constriction is this constriction produced by the bifurcation of the trachea into the left and the right principal problems 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 ease of vigil And the third constriction is at the ease of vigil 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 crust of the diaphragm The right crust of the diaphragm as it goes it completely encircles the ease of vigours and it comes back again This constitutes the lower ease of vigil sphincter and this constitutes the lowest constriction for the diaphragmatic constriction This is another barium swallow to show the diaphragmatic constriction and the dilatation of that called the phrenic ampulla So we have seen the two sphincters as 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 ease of vigours is the inferior thyroid artery This is the thyroid and the inferior thyroid artery is a branch of the Subclavian artery Venus drainage is to the inferior thyroid vein which drains into the brachialcephalic vein the thoracic part of the ease of vigours the blood supply is from the descending thoracic aorta the ease of vagal branches and the venous drainage is to this vein here This is the gaseous vein So this is also part of the systemic circulation because it drains into the supia vena gava Abdominal part of the ease of vigours 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 ease of vigil branch of the left gastric artery supplies the abdominal part of the ease of vigours 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 ease of vigours belongs to the portal circulation The rest of these are figures belongs to the systemic circulation So in the sub-bucosa of the ease of vigours 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 ease of vigil 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 maternal cirrhosis of the liver and This is an ease of vigours scopic view the lower end the ease of vigours to show ease of vigil varices Which I described just now The next point which I want to mention to you was about the nerve supply of the ease of vigours 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 sub-cavian artery and is entering into the thorax It is going behind the helm 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 helm of the left lung and below the helm 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 bilia plexus The right vagus, the posterior vagus is the larger one and it supplies up to the neck cap Surveical 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 serosal 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 serosal covering in the thoracic part of the isophagus while doing an isophagoscopy rupture of the isophagus and various unit is 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 Sympathetic 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. That's all for now. Dr. Sanja Sanyal signing out David was the camera person my MD1 students are my silent spectators. If you have any questions or comments Please mention the comment section below. Have a nice day