 Let's take a look at the parts of the penis attached to the ischemic ramus on either side the roots of the penis Which are called the crura penis and they are composed of corpora cabernosa and in the midline We have another part of the root of the penis which we cannot see that is known as the bulb of the penis So therefore the root of the penis composed of two crura and one bulb They all meet in the lower part of the symphysis fibrous where it's known as the angle Then we have the shaft of the penis Then we have the glance of the penis the junction between the shaft and the glance in this location This is known as the corona glandis now Let's take a look at the structure of the penis on the torso aspect where my finger is pointing are two blood-filled spaces And they are called the corpora cabernosa These are the ones which came from the crura of the penis on the ventral aspect He had this structure here, which I have lifted up for the time being please disregard this structure Which I will describe later on this is the corpus spongiosum and this contains spongy tissue and inside this is the urethra And this corpus spongiosum is the one which continues on the ventral aspect all the way And it becomes a glance penis and at the tip of the glance penis We have the opening of the urethra that is the external urinary theaters So this is the structure of the penis. Let's take a look at the coverings of the penis First of course, we have the skin the prepuse is a double fold of skin The outer layer is the usual skin and then it makes a bend and we can see it is folding inside And this second layer goes and gets attached to the corona glandis So this double fold of skin that we see here This is the prepuse the outer layer is stratified squamous scared nice epithelium And the inner layer which is in contact with the glance penis is the stratified squamous non-cared nice epithelium If there is tightening of the prepuse then that is called phymosis and if the prepuse is excised that condition is known as Circumcised penis after the skin we have the next layer which has been removed here That's a layer of superficial fascia and that is called the dartos fascia The dartos fascia is the continuation of the scarpa's fascia the membranous layer of the superficial fascia of the abdomen Which also covers the penis under that we have the third layer and that is this we have retained a little bit of it And this is known as the bux fascia bux fascia is distinct from dartos fascia The bux fascia is a deep fascia Attached to this bux fascia the deep fascia is the suspensory ligament of penis Which is the main ligament which suspends the penis to the symphysis pubis And then we have the next layer which encloses the two corpora cavernosa And that is a very tough thick layer and that is known as tunica albogenia And there's a septum in between we separate the two corpora cavernosa at this juncture I can mention that the bux fascia covers all the three structures namely the two corpora cavernosa and the corpus spongebosum But the tunica albogenia covers only the corpora cavernosa So these are about the layers of the coverings of the penis now. Let's take a look at the neurovascular structures Superfisher to the bux fascia is this vein here This is the superficial vein of penis and I complete this will be the superficial artery of penis Which supply the skin and the subcutaneous tissue? They are derived from the femoral artery and the femoral vein the superficial external pudendal artery and external pudendal vein Under the bux fascia in the midline. We have this prominent vein here This is deep dorsal vein of penis. This has not to be confused with the superficial dorsal vein of penis This deep dorsal vein of penis is in the midline and we can see it here And this is the one which continues in the midline. This is the one which is responsible for Flaxidity after erection. It drains the blood fill spaces inside the corpora cavernosa And once they drain this deep dorsal vein of penis goes into the pelvis into the perineum above the perineal membrane It does not go through the perineal membrane. It goes above the perineal membrane Between the perineal membrane and the symphysis pubis and it drains into the prostate venous flexors And that is how detubicens or flaxidity occurs after erection on either side of this deep dorsal vein of penis We have this artery here And we have this artery here. These are the dorsal arteries of penis And then we have this nerve here and this nerve here. These are the dorsal nerves of penis So we have five structures deep to the bux fascia What is not visible here, but we will see when we cut the penis will be two deep arteries One each in corpora cavernosa And they are the deep arteries of penis and they are the ones which are responsible for Filling the cavernous spaces with blood by means of small arteries called helicine arteries And that's the ones which produces erection. So therefore in simple terms the deep arteries of penis I have the helicine arteries produce erection in the corpora cavernosa and the deep dorsal vein of penis Rains away the blood and produces Flaxidity or detubicens after erection is over. So these are the vascular structures that we can see here Next part of the dissection We are going to cut the penis transverse deep to show the two corpora cavernosa on the dorsal aspect and the corpus pangeosum On the ventral aspect and we will also show the tunica albogenia covering the corpora cavernosa And that will explain the mechanism of erection So my assistants have done a wonderful job of slicing the corpora cavernosa and the corpus pangeosum So we can see that these are the two halves of the corpora cavernosa This is the proximal cut end and this is the distal cut end And we can see it is first covered by this thick white membranous structure here This is the tunica albogenia the tunica albogenia covers the two corpora cavernosa And it also gives a septum between the two and we can see the same thing here also And it is this tunica albogenia Which is one of the main structures which is responsible for erection This corpora cavernosa is filled with multiple spaces And when they get filled up with blood by means of dilatation of the helicine arteries Tunica albogenia prevents lateral expansion So therefore the penis expands forward and that's what produces erection If there is a rupture of this tunica albogenia that condition is called fracture of penis And that can lead to flaccidity and it is repaired by suturing the corpora cavernosa Likewise if there is thrombosis of the blood filled spaces inside the corpora cavernosa Like for example in polycythemia vira there will be persistent painful erection of the penis And that condition is known as priapism The next structure which I will draw your attention to is this one which is on the ventral aspect This is the proximal cut portion. This is the distal cut portion. This is the corpus fungiosum This is not enclosed in the tunica albogenia. It contains in its center this opening here And we can see this opening here also This is the corpus fungiosum with the pinidirutra inside If it were covered by the tunica albogenia it would have constructed the uritra So therefore this is not covered by tunica albogenia However, it is enclosed in a deep fascia of the penis which is known as the Bux fascia. Bux fascia encloses all these three structures together namely the corpora cavernosa and the corpus fungiosum So the structure of the penis is dorsally the two corpora cavernosa and ventrally the corpus fungiosum These are the structures which I wanted to show you in this particular dissection Thank you very much for watching. Please like and subscribe. Dr. Sanjay Sanyal signing out. If you have any questions or comments Please put them in the comment section below. Have a nice day