 This is a supine cadaver. I'm standing on the right side. The camera person is on the left side. Just to bring up the speed, these are the two kidneys. This is the inferior vena cava. This is the abdominal aorta. And we have cut the inferior vena cava here where it was entering into the liver. The classical teaching is that the renal arteries arise from the abdominal aorta just below the level of the spherymesic artery. But here we see that the renal arteries are different. So let's start at the right side first. I have lifted up the right kidney. And we can see, first of all, this is one renal artery arising from the abdominal aorta. This is number one. When I lift up the inferior vena cava, you see yet a second renal artery. This is the second renal artery coming from the abdominal aorta. And we see a third renal artery also coming from the abdominal aorta. So we see three separate renal arteries coming from the abdominal aorta and entering into the kidneys separately. So let's trace them once more. This is the first one. And we can see it is coming across and it is dividing into two branches. The second one is this one. It started from the abdominal aorta just below the first one. And it went across and it went to the posterior surface of the kidney here. And it is also giving this branch which is coming to the anterior surface of the kidney. And this is the third one. The third one is something unique. We can notice that it is running behind the ureter. The traditional teaching is that the ureter is supposed to be the most mysterious structure, the pelvic calcium system. But here we notice that the third renal artery is behind the ureter. Furthermore, the renal artery as we know once it enters into the kidney, it divides into five segmental arteries as shown in the accompanying angiogram. And the segmental arteries are as follows in a normal circumstance. We have a superior which goes to the upper pole of the kidney. We have an inferior which goes to the lower pole of the kidney. Then the anterior branch divides into an anterior superior, anterior inferior and then we have a posterior segmental artery. So this is the traditional five segmental arteries. This is the right renal angiogram to show the five segmental renal arteries. Let us see how those five segmental arteries relate to this distribution because we have already seen there are three separate renal arteries. So therefore this first renal artery, this branch corresponds to the superior polar artery. This one corresponds to the anterior superior branch. Then the main renal artery that we trace from here, this goes as the posterior renal artery and it is going on the posterior aspect as we can see here. But it is also giving this branch here. This corresponds to the anterior inferior branch. We also notice that the main renal artery which we mentioned, this one is giving this branch here. This is the right superior glan. This is the artery from the renal artery going to the right superior glan. And the last artery that we picked up here which we said goes behind the ureter. This corresponds to the inferior branch which goes to the inferior pole. So this is how we can relate. The kidney as a kidney ascends up during embryonic development. It is the posterior most structure and therefore the renal vessels, they are all located in front and the pelvic system is located behind. But the fact that this renal artery, the ureter is running in front, it indicates that this particular renal artery and this portion of the kidney developed in a different way. And this is in a strictly speaking a postulate. Now let us take a look at the vein. As I mentioned, this is the inferior vena cava. And we can see that the inferior vena cava is giving rise to this branch here, which is the main renal vein. And the renal vein immediately is dividing into two principal divisions and it is dividing further and it is entering into the hyalum of the kidney. And finally, as I mentioned earlier, this is the renal pelvis and the chelicis. This is the hyalurotrophic kidney, therefore the pelvic chelicis system is hyalurotrophic. And we can see the very widely dilated renal sinuses and these are the pelvic chelicis system converging onto the renal pelvis. And this is the pelvic uretric junction and we can see the ureter is running in front of the lowest branch, the renal artery. So this is what we see on the right side. Now let us take a look at the left side. Left side kidney is also hyalurotrophic. We will start with the left renal vein because the left renal vein as we know is longer than the right renal vein and it is located in front of the abdominal aorta. So this is the left renal vein. The left renal vein is dividing into three branches. One branch has been broken here because it was thrombosed and we can see the other two branches which are entering. We notice that the left renal vein is receiving this vein here. This is the vein from the left suprarenal gland and we know that the left suprarenal vein drains into the left renal vein and it also communicates with the left inferior phrenic vein. We also notice the left renal vein is receiving these two veins. These are the gonadal, in this case the disticular vein. There are two in this particular cadaver. Having mentioned the renal veins, now let us come to the renal arteries. So again, let us start from the abdominal aorta. We see this artery. This is the main renal artery and the renal artery as it comes towards the kidney, it divides into two branches. One branch we can see is this one. This is going on the posterior aspect and this is the anterior branch which we have cut which supplies the anterior surface of the kidney. Then we notice yet another branch coming independently from the abdominal aorta and it is this one here. This one is arising from the aorta approximately at the same level as the artery on the other side. And it is going again behind the ureter and it is going to the lower pole of the kidney. And this one we can see is accompanied by a completely independent renal vein. Part of that is visible here. So therefore again to trace the segmental arteries, this being the main renal artery, the anterior branch. This is the anterior superior. This is the anterior inferior. The posterior division, this portion is the superior polar. And the rest of this is the posterior branch and this branch independently is the inferior branch. So that is what we can postulate about the segmental distribution on the left side. And finally again to conclude, we can see this is the pelvic keli-steel system and this is the renal pelvis formed by the union of the major and the minor keli-sis and this is the pelvic ureteric junction. And again on this side also we notice that the ureter is running in front of the lowest branch. The clinical significance of this is that because the right kidney is receiving three separate renal branches, if one or more of these branches get blocked or there is any pathology, there will still be blood supply from the other branches. And the embryological significance that we postulated is also another possibility that we should keep in mind. So these are the findings which I wanted to show to you on the renal sinuses and the renal hyalum on both the sides.