 Good day everybody. Dr. Sanjay Sanyal, professor department chair. This is going to be a demonstration of the media channel insider. So to bring up the speed, this is the supine cadaver. This is the left side. There's the right side of the cadaver. The camera person is on the left side. I'm standing on the right side. So first let's take a quick look at the structures of the root of the neck. The root of the neck is at the level of team one. Basically at the root of the neck we have the great vessels. So this is the left brachycephalic vein. There's the right brachycephalic vein. And each brachycephalic vein as we can see is formed by the union of the subclavian vein and the internal jugular vein. On the left side, the subclavian vein and the internal jugular vein on the right side. This union being referred to as the venous angle. This union takes place at the level of the sternoclavicular joint. And then we have the left brachycephalic going obliquely. And then we have the right brachycephalic. And this union makes big at the level of first rib. And then the supiavenecava is formed. The supiavenecava, strictly speaking, is in the superior mediastinum. And part of the supiavenecava is enclosed in this fibrous pericardium. So this is about one great vessel. From the root of the neck to the superior mediastinum. Now let's take a look at the next one. We see this structure here, which I have lifted up. This is the arch of Eurota. The arch of Eurota is the next great structure, which is present in the superior mediastinum, and its branches go from the root of the neck. So let's take a look. The arch of Eurota goes obliquely posteriorly. The ascending portion of the Eurota, then we have the arch of Eurota, then we have the descending thoracic Eurota. From the arch, we have this vessel. This is the brachycephalic trunk. Brachycephalic trunk divides into right subclavian, right common corollary. Then we have the next vessel, which is this one. This is the left common corollary. And then we have the next vessel. This is the left subclavian. And then the arch of Eurota descends down. This is the digital subtraction angiogram to show the arch of Eurota and the great vessels arising therefrom. When I lift up the arch of Eurota below that, we can see yet one more vessel. Dividing under the arch of Eurota, we have this. This is the pulmonary trunk. The pulmonary trunk does not divide exactly under the arch of Eurota. It divides a little to the left of the arch of Eurota. So therefore, the left pulmonary artery is away from the arch and the right pulmonary artery goes under the arch. And I'm going to show you the rest of the pulmonary artery when I come to the high limb of the lung. So these are the structures that we can see in the root of the neck and in the superior medius tandem. To summarize briefly, the superior medius tandem contains the three great vessels. Namely, the superior vena keva, the arch of Eurota, and the pulmonary trunk. Now let's shift our focus to this structure that we see here. This is the heart as we have already guessed covered by the fibrous pericardium and we have split it open in several places. And we can see that the fibrous pericardium is tough and leathery. Fibrous pericardium is roughly cone shaped. The apex of the cone fuses with the tunic adventurer of the great vessel. More specifically, the arch of Eurota at the junction between the ascending and the arch of Eurota. And we can see that here we have split it here. And the base of the cone is the fibrous pericardium which gets attached to the central tendon of the diaphragm. And this was the place. And to show you exactly where I'm going to bring the thoracic cavity here. And this was the location where it was attached to the central tendon of the diaphragm. And here it is fused by means of ligament which we can see remnant of that is the pericardiophrenic ligament. So this was where the base was located and it was sitting on this. Now I'm going to remove this out. Once we split it open, we can see the pericardial cavity. Under the fibrous pericardium lining the inner surface of the fibrous pericardium here is the parietal layer of the serous pericardium. And lining the surface of the heart is the visceral layer of the serous pericardium which is also referred to as epicardium and we can see it is laden with fat. So therefore this is the pericardial cavity which we have highly exaggerated. There are two portions of the pericardial cavity which requires special mention and they are called pericardial sinuses. The first one is this one where my hand is gone in. It is gone obliquely up and to the right. This is called the oblique pericardial sinus. This is a dead end. The dead end being formed by the four pulmonary veins and the inferior vena kiva and the superior vena kiva opening into the heart. This is the oblique pericardial sinus and this forms the posterior relation of the base of the heart namely the left atrium. The next sinus is the transverse pericardial sinus which is surgically very important and I'm putting my finger in the transverse pericardial sinus right now and if you notice very carefully in front of my finger is located the arch of aorta and ideally even the pulmonary trunk should be located in front and behind my finger is located the superior vena kiva. So this is referred to as the transverse pericardial sinus. Transverse pericardial sinus embryologically is the remnant of the space between the arterial end of the heart and the venous end of the heart and the heart you fold it. This is an amorengogram to show the transverse pericardial sinus between the aorta and the svc. This transverse pericardial sinus is used by cardiothoracic surgeons to cannulate the aorta and the superior vena kiva prior to open heart surgery in order to connect these great vessels to the heart lung machine that is the surgical importance of this transverse pericardial sinus. This is a schematic diagram to show the heart lung machine learning from the venous end to the arterial end. And if I were to put my finger further lower down in the transverse pericardial sinus it stops at one place. That is the lower limit of the transverse pericardial sinus which is bounded by again the base of the heart formed by the left atrium. So these are the two cavities. We need to mention a few other points. This pericardial cavity can get filled with abnormal fluid. Normally it contains very small amount of fluid to allow frictionless movement but if there is excessive collection it is referred to as pericardial effusion. Or it can have collection of blood when it is known as hemopericardium. It can have collection of air which is known as pneumopericardium. These are playing just x-ray to show pneumopericardium indicated by the arrows. If there is correction of fluid we need to tap it and that is called pericardial synthesis. And how do we do it? We go slightly to the left of the Z-fight process and we go in this region. We go to the left between the fifth and the left sixth intercostal space where my finger is located. This region of the pericardium is referred to as the bare area of the pericardium. The word bare is a relative term. It means that this portion of the pericardium is in direct contact with the chest wall because the visceral pleura has moved away by virtue of the cardiac notch and the lingular process of the left lung. So therefore we can push the needle here without injuring the pleura. So this is the region where we do a pericardial synthesis. So that is about the fibrous pericardium. More will follow when we dissect out the heart. And before I go out of this I just want to draw your attention to this portion here. We can see the remnant of the diaphragm here also. So this was where the inferior or the diaphragmatic surface of the heart was sitting. And we can also see opening of the inferior vena keva which is highly thrombosed here. It is piercing through the central tender of the diaphragm and it's entering into the heart. So that's all we can see in this particular structure. Thank you very much for watching. Dr. Sanjay Sanyal signing out. David O is the camera person. If you have any questions or comments please put them in the comment section below. Have a nice day.