 Dr. Sanjay Sanyal, Professor Department Chair. This dissection demonstration is going to be on the anterior cervical region. So this is the posterior boundary of the anterior cervical region followed by the anterior border of the sternoclear mastoid. The superior boundary of the anterior cervical region is by the inferior margin of the body of the mandible and a straight line drawn from the angle of the mandible to the mastoid process. And the anterior boundary is the median plane of the neck shown by this instrument here. So this is the boundary of the anterior cervical region. The anterior cervical region roof is formed by the platysma. The distinct layer of deep cervical fascia does not come into the anterior cervical region. The floor is formed by the pre tracheal fascia. The anterior cervical region is further subdivided into four other triangles. Now let's take a look at the submental triangle within the anterior cervical region. The submental triangle is actually a median triangle. It is shared equally by both the sides. The two lateral boundaries are by this muscle and by this muscle. These are the anterior belly of digastric of the right and the left side respectively. Both of them meet in the region of the symphysis mentai or the mandibular symphysis. This is the apex of the triangle. And the base of the triangle is the hyoid bone. So this is the submental triangle. The roof of the submental triangle is formed by the platysma. The floor of the submental triangle is formed by this muscle where my instrument is touching. This is the mylohyde muscle. So there is a mylohyde muscle on the right side and there is a mylohyde muscle on the left side and both of them meet inside in the median raffae. And this is covered by the pre tracheal layer of cervical fascia, the muscular component. So the contents of the submental triangle are submental group of lymph nodes. Then we have the submental artery and we can see a branch of the submental artery coming here. It is a branch of the facial artery. And we have the submental veins. So these are some of the submental veins which are coming here and they go down and unite to form the anterior jugular vein. So these are the three contents of the submental triangle. Now we come to the submandibular triangle. The submandibular triangle is bounded posteriorly by these two muscles. This is the posterior belly of digastric which I have lifted up. And this is the stylohyde. The posterior belly of digastric is coming from the mastoid process and it is becoming an intermediate tendon which is attached to the greater corner of high bone by means of a digastric sling. The stylohyde is coming from the stylohyde process and it is fitting to allow the attachment of the intermediate tendon of the digastric. The anterior boundary is formed by the anterior belly of digastric which is starting from the intermediate tendon under the digastric sling and getting attached to the digastric fossa of the mandible. And the superior boundary is formed by the inferior margin of the body of the mandible and an imaginary line drawn from the angle of the mandible to the mastoid process. So this is the submandibular triangle. The most important content of the submandibular triangle is this structure that I have lifted up. This is the submandibular salivary gland. Additionally, it also contains the submandibular lymph nodes. It contains the facial artery, facial vein, and deep inside we can see the lingual nerve. These are the main contents of the submandibular triangle though a little bit of the lingual artery loop and the hypoglossal nerve may also form part of the contents of the submandibular triangle. Now we come to the carotid triangle in the anterior cervical region. Pustially, we have the anterior boundary of the sternocleidomastoid. Anti-reinferially, we have the superior belly of the omohiaoid picked up by this instrument. Anti-reinferially, we have these two muscles. Most importantly, the posterior belly of the digastric. So this is the carotid triangle. The roof of the carotid triangle is again formed by the pratisma. The floor of the carotid triangle is formed by the muscular component of the critical layer of the deep cervical fascia. The contents of the carotid triangle are, we can see them here, the carotid sheath, which includes the internal jugular vein, the common carotid artery, the internal carotid and a portion of the external carotid with the respective branches and tributaries and some of the cranial nerves which I'm going to demonstrate subsequently. One more content of the carotid triangle is the carotid body which is not visible here which is located at the bifurcation of the internal and the external carotid artery. Carotid body is a peripheral chemoreceptor while the dilatation of the internal carotid artery, the carotid sinus is a baroreceptor. The fourth triangle of the actual cervical region is the muscular triangle or the omotracheal triangle. It is bounded posterior superiorly by the superior belly of omohiaoid, posterior inferiorly by the lower part of the anterior border of the sternocular mastoid and anteriorly again it is the median plane of the neck. So this is the muscular or the omotracheal triangle. The roof of this triangle is again formed by the pletisma and the floor is formed by the visceral component of the pre-tracheal patient. And the contents of this triangle are the thyroid gland, the parathyroid gland, the infrared strap muscles, the anterior jugular vein with all its tributaries and communications and the jugular venous arch and lymph nodes. The small veins in the sub-mental region, they all unite to form the anterior jugular vein. We can see the anterior jugular vein on the right side and we can see the anterior jugular vein on the left side. The anterior jugular vein then descends down in the muscular or the omotracheal triangle and at the lower end, the two anterior jugular veins, they have a communication which is located in the suprasternal space of burns and this communication is known as the jugular venous arch. And thereafter, the anterior jugular vein on each side opens into the external jugular vein. So this is the course of the anterior jugular vein and the anterior jugular vein also has a communication with the facial vein, which we can see clearly here. Thank you very much for watching. If you have any questions or comments, please put them in the comment section below. Thank you so much for sending us your signing off. Have a nice day. Guys, make sure you like this video. Make sure you click the subscribe.