 So we have completely removed all the scalp structures. We have reflected them and we have pinned them here. So this is the temporal region This is the right side. I'm standing on the right side and the camera person is also on the right side This is the layer which I have lifted up. This is the temporal parietal fascia The temporal parietal fascia is the lateral extension of the glia aponeurotica So this is the glia aponeurotica and the lateral extension of that is called the superficial temporal fascia Or the temporal parietal fascia and we can see running in the superficial temporal fascia these blood vessels and These thrombose vessels these are the superficial temporal veins and accompanying them will be the superficial temporal artery and The auricular temporal nerve. So let's reflect that once we reflect then we can see this layer here This is the deep temporal fascia or the temporal fascia proper We have removed the periosteum from the skull here and we have reflected here and we see deep temporal fascia is Attached to the superior temporal line and we have reflected the deep temporal fascia here one half of it and the other half of it And we notice that this deep temporal fascia as it comes down it becomes very thick and not only that it splits into two layers This is one layer and this is the other layer The lower thick portion the outer layer attaches itself to the outer surface of the zygomatic arch And this is the zygomatic arch here and the inner layer gets attached to the inner surface of the zygomatic arch So this is the deep temporal fascia the two layers attached to the zygomatic arch Now this serves a very important function This gives a very strong counter traction with the zygomatic arch from above and it counters the pull of the miscellaneous muscle which is here When the miscellaneous muscle contracts vigorously it tends to pull on the zygomatic arch from below that is countered by this deep temporal fascia Now let's come to the boundaries of the temporal fossa superiorly and posteriorly The boundary is the superior temporal line to which I mentioned was attached the deep temporal fascia So that is the inferior temporal line which I shall mention just now Anteriorly we have this boundary here This is partly formed by the frontal bone and partly by the zygomatic bone where my finger is tracing Laterally is the zygomatic arch which is formed by the zygomatic process of the temporal bone And the temporal process of the zygomatic bone together constituting zygomatic arch The floor of the temporal fossa is formed by four bones which we cannot see They are from the frontal bone, the parietal bone And deep inside will be the greater ring of sphenoid, posteriorly will be the squamous part of temporal bone This is the picture of the skull to show the four bones constituting the floor of the temporal fossa and the location of the diria This is another cadaver dissection where we have reflected the temporalis fossa to show you the floor of the temporal fossa This is the region of the tirion The floor is composed of four bones Frontal bone, parietal bone, greater ring of sphenoid and squamous part of temporal bone And in this region they form an H-shaped suture which is referred to as the tirion The significance of the tirion is that the anterior division of the middle menageal artery runs under the tirion embedded in the endosteum This is the plain x-ray of the skull that will be able to show the vascular markings produced by the anterior and posterior divisions of the middle menageal artery And if there is a fracture to the temporal region then the middle menageal artery anterior division can rupture and it can produce extracellular hematoma which will require a burr hole This is the non-contrast city of the skull to show fracture of the temporal region of the left side and an extracellular hematoma When we have a patient with extracellular hematoma we do a burr hole by splitting the fibres of the temporalis muscle Then we make a burr hole here and we like the anterior division of the middle menageal artery So that brings me to the next point Given a normal situation like this, how do we locate the position of the tirion? There are several ways of doing it. One of them is take the zygomatic arch, take the midpoint of the zygomatic arch Go one and a half inch above the midpoint that is the location of the tirion Another method is to consider the triggers of the ear and go three fingers behind the triggers of the ear and two fingers behind the frontal bone and where they meet that is the location of the tirion These are two of many methods which are used to locate the approximate location of the tirion before doing a burr hole So that is all about the temporal region