 Good day everybody. Welcome to our demonstration of the lung specimens. I'm Dr. Sanjay Sanyal, Professor Department Chair. How do we know that this is the right lung? First of all, it's large in size, but more importantly, we can see that it has got two fissures. This fissure here, this is the horizontal fissure and there's another fissure which goes obliquely up and that's the oblique fissure. The horizontal fissure cuts the anterior margin of the lung at the level of the fourth rib. And the oblique fissure cuts the inferior margin of the lung at the level of the sixth rib. The horizontal fissure continues and meets with the oblique fissure. The oblique fissure goes obliquely up along the posterior surface of the lung and then it comes again and meets with the high lung of the lung from the posterior superior aspect. At the same time, the oblique fissure also meets the high lung of the lung from below from its anterior inferior aspect. The horizontal fissure, as we mentioned, it cuts the anterior margin of the lung at the level of the fourth rib and it continues onto the middle surface and it meets with the high lung of the lung from its anterior aspect. So this is the termination of the fissures. So now that we have the two fissures in place, the horizontal and the oblique fissure, that divides the lung into three lobes, the right one. This is the superior lobe, this is the middle lobe and this is the inferior lobe. So only the right lung has got three lobes. If you look closely, you will notice that the inferior lobe of the lung is situated more posteriorly. And therefore when we ascultate the posterior chest wall, we see the findings as they are in the inferior lobe of the lung. And at the same time, the superior lobe and the middle of the lung are more in relation to the anterior chest wall. So when we ascultate or percuss on the anterior chest wall, we see the findings in the superior lobe of the middle lobe. Now let's take a look at the landmarks on the lateral surface also referred to as the costal surface of the lung. The shiny thing that you see here is the bicarbonate pleura. And we can see the sub pleural lymphatics with the entrapped carbon particle laden macrophage here. If this had been a smoker, then this lung would have been completely black. These red patches that you see are all evidences of old pleurisy. The next important point that we see on the lateral surface are these shallow parallel depressions. These are the costal markings. These are the impressions produced by the ribs. Now let's take a look at the parts of the lung. This is the apex of the lung. And this is the portion of the lung which is above the first rib and discovered by the cervical pleura, cervical fascia, also referred to as the supra pleural membrane of the sipson's fascia. This is the one which is extending above the first rib. This is the anterior margin of the lung. The anterior margin of the lung by definition is sharp. And this is the one which fits into the costo mediastinal recess. This is the inferior border of the lung. This inferior border of the lung is also sharp. And this is the one which fits into the costo diaphragmatic recess. And this is the posterior border of the lung which is blunt. And this is the one which fits into the costo vertebral recess. That brings me to the surfaces of the lung. the lung. This surface as I have already mentioned is the lateral surface or the costal surface which is in relation to the ribs. This surface the concave this is the medial surface or the medial-stinal surface and this surface that we see here this is the inferior surface or the diaphragmatic surface and this is the one which is resting on the dome of the diaphragm in this case it will be resting on the right dome of the diaphragm. So the inferior border completely encircles the inferior surface. Now let's take a look at the medial-stinal or the medial surface of the lung. Let's take a look at this on cave depression. This is called the the cardiac impression and in this case this is related to the right atrium. This is the right atrial surface of the lung. This depression and this continues down and then it continues down like this this one. This is the right brachiocephalic impression continuing as the superior vena keva impression and we know right brachiocephalic continues as the superior vena keva and that opens into the right atrium. Similarly we can see an impression here this is the inferior vena keva impression and we know that inferior vena keva also opens into the right atrium. If you remember that there was the azygosvane. The azygosvane it goes behind the bronchus behind the pulmonary hyalum on the right side and then it hooks from the posterior aspect as the arch of the azygos and it opens into the superior vena keva. So this depression is the impression produced by the arch of the azygosvane and the azygosvane the rest of the azygosvane then travels down so therefore this portion of the posterior border of the right lung is also related to the azygosvane. Now let's take a look at this portion here this impression. This is the esophageal impression because we know that the esophagus is more in relation to the right side. So this is the esophageal impression. Running in front of the hyalum of the lung like this will be the phrenic nerve and running behind the hyalum of the lung will be the vagus nerve. Now let us come to the hyalum itself. The hyalum of the lung by definition is the place where the structures enter the lung or exit the lung. So this is the hyalur structures. The hyalum of the lung is also the place where the visceral pleura of the lung becomes continuous with the parietal pleura namely the medestinal pleura. So this is the place of continuity and the place where the two pleural surfaces meet the visceral and the parietal pleura there is a small extension of that which you can see here. Rest of it has been cut off and this double fold of pleura which hangs down from the hyalum of the lung that is known as the pulmonary ligament. The three most important structures in the hyalum are the bronchial tree, the pulmonary artery and the pulmonary vein. How do we recognize the bronchi? The bronchi are recognized by their feel and we can feel the cartilage of the bronchi. So this is a bronchus here. This is the one bronchus, this is another bronchus and this is the third one. So we know that the right principle bronchus divides into three low bar bronchi. So this is the bronchial tree. The pulmonary arteries there are two of them as I mentioned before they tend to the right lung. So these are the two openings of the pulmonary arteries. Pulmonary veins are very numerous and many but when they finally exit the lung there will be two pulmonary veins. So there will be smaller in diameter, there will be numerous and they will be distributed all over but the standards take books say that the pulmonary veins are situated more in the anterior inferior aspect then we have the pulmonary artery and then we have the bronchi. What else do we see? I would draw your attention to this structure which I have retained here, to this structure and all these cut portions of these structures here. These are the bronchopulmonary or the hyalurlimph nodes and normally you can see the black spots in the hyalurlimph nodes. So they are the ones which are actually filled with carbon particle laden macrophages which have been trapped by the hyalurlimph nodes. So these are the salient structures and points that we see on the right lung. Thank you very much for watching, ladies and gentlemen. If you have any questions or comments please put them in the comment section below. Have a nice day. Dr. Sanjay Sanyal signing out. Like this video and make sure you click to subscribe.