 Good day everybody, Dr. Sanjay Sanyal, Professor of Department Chair. This is going to be a demonstration of vessels of the pelvis. This is a supine cadaver. I'm standing on the right side and the camera person is also on the right side. So let's start from this bifurcation of the abdominal aorta, which is at the level of L4. And we can see this is the right common iliac artery. This is the left common iliac artery. At this duct itself, I can mention that the common iliac artery is crossed over by the ureter at the pelvic brim on either side. And this is the place where the ureter has got a normal physiological constriction, which can be a site of impaction of the stone. To continue, the common iliac artery divides into an external iliac artery and an internal iliac artery. The external iliac artery continues along the pelvic brim and it goes under the inguinal ligament where my finger is going. And the moment it crosses the inguinal ligament, it becomes known as femoral artery and we can see that here. Well, it is the external iliac artery. It gives this branch here. This is the deep circumfix iliac, which runs along the inner margin of the iliac crest. And another branch it gives out is the inferior epigastric artery, which we can see on this side. This is the inferior epigastric artery. This inferior epigastric artery runs on the inner surface of the rectus abdominis muscle. Now let's come to the internal iliac. When I lift this up, we can see this is the internal iliac. If we look very closely, we see that the internal iliac is the main supply of the pelvis and it runs in a parasurgical axis on the lateral wall of the pelvis. And we have completely separated from the pelvic fascia. The internal iliac artery divides into a posterior division and an anterior division. Let's start with the posterior division first. The posterior division gives three branches. The first branch is this one here. This is the ilio-lumbar artery. The ilio-lumbar artery divides into descending and an ascending or an inferior and a superior. And this ilio-lumbar artery then runs laterally along the iliac crest. Anastomosis with the fourth lumbar artery and also anastomosis with the deep circumfix iliac, which I mentioned earlier. That is the ilio-lumbar artery. The next branch of the posterior division is if I turn this, we can see an artery going towards the midline of the sacrum. This one here. This is the lateral sacral artery. This lateral sacral artery comes from the lateral side. And there's another lateral sacral artery coming from the other side and it anastomosis with the median sacral artery. The median sacral artery is a unique artery, an unpaid artery which ideally arises from the back of the bifurcation of the aorta. And we can see the median sacral artery here is very small and it runs exactly the midline. And the venous counterpart of this we can see here is very big. So they have the median sacral artery and the two lateral sacral arteries, one from this side and another from this side. And they form an arterial anastomosis in front of the sacrum. So that is the second branch of the posterior division. The third branch of the posterior division is this one here, which we have lifted up. This is the superior gluteal artery. And if we trace it further, we can see that the superior gluteal artery exits the pelvis. When my hand finger is disappeared of the piriformis through the greater sciatic foramen and it enters into the gluteal region. So therefore to summarize the posterior division of the internal iliac gives ilio lumbar, the lateral sacral and the superior gluteal. Now let's come to the anterior division. This is the anterior division, this whole thing. The anterior division has got the following branches. This is the first branch. This is the umbilical artery. The umbilical artery as we know in embryonic life, it carries deoxygen blood to the placenta for oxygenation. After birth, the distal part of the umbilical artery obliterates, becomes fibrozed as we can see it here and it forms the medial umbilical ligament. And we can see the two medial umbilical ligaments one on either side. However, the proximal portion of the umbilical artery remains patent and we can see that here also. And the proximal portion gives these branches that we can see here. It gives numerous branches which go to the bladder. So these are the superior vesicle arteries. There are many of them. They all come from the proximal portion of the umbilical artery which is patent and they supply the dome of the bladder. Then there is supposed to be an inferior vesicle artery coming further behind from the anterior division of the internal iliac which we cannot see clearly here. This supplies the posterior part of the dome and the base of the bladder. In females, inferior vesicle artery is absent. It is replaced by uterine artery and the branch of the uterine artery named vaginal artery. And this is a male cadaver so therefore we don't have that one here. The next branch that we can see here is this one which I have lifted up. This is the operator artery. And we can see that the operator artery is accompanied by this nerve here. This is the operator nerve and deep inside there is an operator vein. So these three structures, they all pass through the operator for a minute but my instrument has disappeared. And they go through the operator canal which is an opening in the operator membrane and they come to the medial side of the thigh. That is the third branch. Then we have the next branch, the middle rectal artery. See the middle rectal artery. We have to lift up the rectum and this is the rectum here and we can see this branch coming to the middle. This is the middle rectal artery. This travels from lateral to medial in a ligamentous structure which is a condensation of the endopelvic fascia. That ligament is known as the lateral ligament of the rectum. And finally we have the last two branches. This branch, this is the internal pudendal artery and this is the inferior gluteal artery. Both of them exit the pelvis through the greater sciatic foramen below the piriformis. The internal pudendal artery then enters the palladium through the lesser sciatic foramen and it supplies the palladium. While the inferior gluteal artery, it supplies the gluteal region and it has anastomosis with structures of the thigh where it forms a trochanteric anastomosis. Therefore to summarize again, the anterior division gives six branches. The umbilical artery. From the umbilical artery comes the superior vesicle arteries. Then we have the inferior vesicle artery or the uterine and the vaginal arteries in females. Then we have the obturator artery. Then we have the middle rectal artery. Then we have the internal pudendal artery and then we have the inferior gluteal artery. So these are the branches that we can see of the internal iliac and they supply the structures of the pelvis. Now let me show you one more structure. We have lifted up rectum here and we can see this artery. Coming from the abdominal aorta at the level of L3 and entering into the pelvis and supplying the rectum. This is the inferior vesicle artery. Once it goes into the pelvis it becomes known as the superior rectal artery. And we can see this accompanying vein. This is the superior rectal vein. This supplies the upper part of the rectum and here it is the continuation of the inferior vesicle artery. Inferior vesicle vein is the continuation of superior rectal vein. Therefore the upper part of the rectum is supplied by the superior rectal artery and the middle rectal artery. There is an inferior rectal artery which comes from the internal pudendal artery. But that is in the perineum. Strictly speaking it does not supply the rectum though it is called inferior rectal artery. It supplies the anal canal. So these are the structures that we can see here. And before I conclude I want to show you one more important relationship. Take a look at this triangular shaped area. This is the lateral boundary of the triangle and that is formed by the gonadal or the testicular vessels. And we can see the testicular vessels are coming from the inferior vena cava and the aorta. This is the doctor's difference going immediately. There is a fold of petronium in life here bridging across. So this triangular space is referred to as the triangle of doom. Which is an area of danger during laparoscopic repair of hernia. The reason being when we are trying to reinforce the posterior wall of the anal canal by means of a mesh and we are putting staples. We are likely to injure these two structures which are running through the floor of the triangle of doom. Namely the external ideal artery and the external ideal vein. So therefore in the triangle of doom staples are strictly prohibited. So that is all for now. Dr. Sanjay Sanyal signing out. David over with the camera person. If you have any questions or comments please put them in the comment section below. Have a nice day.