 Okay, so this is going to be demonstration of the common carotid, external carotid and all the branches of the external carotid that we can see here. We have completely exposed the infra-temporal fossa, removed all the structures, parotid fossa removed all the structures, reflected the sternocleidomastoid and opened up part of the submandibular triangle, exposed the lateral cervical region and the entry cervical region to show the full course, this is the right side of the cadaver. So let's start off from here. So this is the common carotid artery coming from the brachycephalic trunk and this is the beginning of the subclavian artery on the right side. So let's focus on the common carotid. This groove that you see here is actually an artifact produced by the mortician. The common carotid artery travels on the medial side of the internal jugular vein and at the level of the superior border of the thyroid cartilage, approximately at the level of the superior border of the thyroid cartilage, it divides into an internal and external carotid and we can see this division here. This is the division. This is the external carotid and the other one is the internal carotid. We shall focus on the external carotid. So therefore the external carotid artery extends only from the level of the superior border of thyroid cartilage, it is located in the carotid triangle of the neck and then it goes like this deep to the posterior belly of the digastric and the stalohyad and it finishes inside the carotid gland as it's two terminal branches. So this is the only extent of the external carotid. The reason why this is called external carotid is because it supplies all the structures outside the skull with a few exceptions that we shall see later. Now let's take a look at the branches of the external carotid. For ease of understanding, we have the rule of one, two and three. The external carotid has got one branch going medially which unfortunately we cannot see here. It is the smallest branch and which goes deep and medially and that is called the ascending pharyngeal artery. We cannot show it in this. The ascending pharyngeal artery runs on the postural lateral aspect of the pharynx and goes straight up. So that is the first branch. Then we have three branches extending anteriorly. Those three branches we can see very clearly here. Coming from below up, the first branch that we can see here is this one. This is the superior thyroid artery. The superior thyroid artery, it enters the upper pole of the thyroid gland and it is accompanied by the externalaryngeal nerve. This is an important artery from the surgical point of view. When we are doing a thyroidectomy, we have to ligate this artery and in the process of ligating, we have to safeguard the externalaryngeal nerve which is liable to be injured. So that is about the superior thyroid artery. The second branch going anteriorly is this one which I have lifted up. This is the lingual artery and we can see that it is slightly torturous and it makes a loop up. This lingual artery is the one which goes into the tongue deep to the higher glosses and in here in the tongue it divides into a dorsal branch, a deep lingual branch and a sublingual branch and it supplies the tongue. This lingual artery is crossed in front by this nerve that we can see here and this is an important relationship. This is the hypoglossal nerve which crosses in front of the loop of the lingual artery and the hypoglossal nerve then enters the tongue superficial to the higher glosses muscle. So that is the second branch that we can see here. The third branch which goes anteriorly is this one which I have lifted up here. I have pushed the lingual artery with my one instrument and with my four steps I am lifting up this one. This is the facial artery, the third branch going anteriorly. The facial artery it goes under this muscle. This is the posterior of digastric and it also goes under the other muscle which is the stylohyard muscle and then it comes on to the mandible and this is the other end of the facial artery and if you notice if I pull here it is getting traction from here. This facial artery it runs inside the body of the mandible. It makes a loop and then it comes out again and then it travels along the lower border of the body of the mandible and it travels up to the face. In the process of doing it is located in the submandibular triangle and in the submandible triangle we have retained part of the submandibular salivary gland. It makes a groove on the posterior aspect of the submandibular salivary gland and we can see this groove here. This groove is produced by the facial artery and we have removed and separated the two. So this is an important relationship of the facial artery and we can feel the pulsation of the facial artery against this bone here, the lower border of the body of the mandible in front of the meseter muscle which has been removed and this is where we can feel the pulsation. Facial artery in the face is highly tortuous as you can see because the face muscles are moving constantly and here it gives several branches. We can see them. This is the submental branch. This is the inferior labial branch. Then it gives a superior labial branch which gives a nasal branch to the nose. Then it gives a lateral nasal branch and it finishes off as the angular artery at the angle of the medial angle of the eye. So this is the full course of the facial artery, part of which we can see here. The importance of the facial artery lies in the fact that when we are doing a submandibular salivary gland surgery because it is so intimately related to the submandibular salivary gland and you can see it is closely related, we are liable to injure the facial artery. So therefore this is one of the structures among many other structures which we have to safeguard when we are doing submandibular salivary gland surgery. That is the third branch which is coming out from the anterior aspect. We have two branches of the external carotid which go posteriorly. I have lifted up this branch here. This is the occipital artery. The occipital artery runs under the posterior digastric as you can see here and it runs very close to the mastoid process near the insertion of the posterior belly of digastric. In fact it makes a groove on the mastoid process and this is the occipital artery which supplies the scalp, the back of the scalp. This is the occipital artery and when it is passing from here it is located at the apex of the lateral cervical region and that is why the upper part of the lateral cervical region is also referred to as the occipital triangle. So this is the occipital artery. That is the first of the two branches going posteriorly. The next branch which goes posteriorly is this artery which I have picked up here. This is the posterior auricular artery. By now the external carotid artery has also come above the posterior belly of digastric and the stylohyoid muscle and here it gives this branch. This is the posterior auricular artery and the posterior auricular artery is accompanied by the posterior auricular vein which we can see here. This posterior auricular artery supplies the skin of the scalp behind the ear. So these are the two branches which go posteriorly and after that the same external carotid artery now enters the substance of the carotid gland. This is the portion of the external carotid which is inside the carotid gland and therefore we can see that the consistency is somewhat different because it was located inside the carotid gland and inside the carotid gland it divides into its two terminal divisions. This is the part of the carotid that we have retained here. The two terminal divisions are we can see the larger terminal division here going inside the intratemporal fossa. This is the maxillary artery which enters the intratemporal fossa and the smaller terminal division is this one here. This is the superficial temporal artery. The superficial temporal artery is tortuous and it runs in front of the tragus of the ear. It runs over the temporal region and it supplies the skin of the temporal region and we can feel the pulsation of the superficial temporal artery against the zygomatic arch which has been removed here. And the superficial temporal artery we can see part of it in this place here on the superficial temporal fascia and we can see the superficial temporal artery here. Coming to the maxillary artery. The maxillary artery is the larger terminal division and it has got three parts. One portion is proximal to the lateral teregoid muscle that is the first part that has got five branches. Then there's a portion which is deep to the maxillary artery that's the second part. That's got four branches and there's a third part which enters the teregopalatin fossa and that is the third part. Here we can see only the branches of the first part of the maxillary artery and let's take a look at them. This is one branch that we can see here of the first part. This is called the deep auricular artery. It supplies the extraordinary meters and the outer surface of the tympanic membrane. The second branch of the first part of the maxillary artery is this one which has been partially cut. This is the anterior tympanic artery which supplies the tympanic membrane from inside. The third branch of the first part of the maxillary artery is this one here which runs in close proximity to the lateral teregoid and this is the middle meningeal artery, the all-important middle meningeal artery. This is the only exception to the rule in so far that this is a branch of the external carotid but it enters the cranial cavity. This enters the cranial cavity through the foremins spinosum and it supplies the meninges of the middle cranial fossa and the posterior cranial fossa and this can rupture in a fracture of the tereon and can produce bleeding which is referred to as extradural hematoma which can be life-threatening. After the middle meningeal artery there is an accessory meningeal artery which is not very visible here which enters also the cranial cavity through the foremins ovei and which also supplies the meninges. The fifth branch of the first part is this artery that we see here this is the inferior alveolar artery and this inferior alveolar artery enters the mandibular canal as we can see here and it runs in the mandibular canal and it supplies the lower teeth and then it comes out from the chin through the metal forearm as the mental artery. So these are the five branches of the first part of the maxillary artery that we can see. So these are all the structures and the branches of the maxillary and the external carotid artery that I wanted to show you starting from here all the way to the infrared temporal fossa with their clinical correlations. Thank you very much for watching. If you have any questions or comments please put them in the comment section below. Have a nice day Dr. Sanjay Sanyal signing out.