Hello, everyone! This is Joao from Kenhub, and welcome to another anatomy tutorial where, this time, we're going to be talking about the neurovasculature of the tongue. Now, the words we’re going to be describing the different arteries, also veins and nerves that are associated to the tongue. And the tongue as you know is a muscular organ of the oral cavity that aids in one thing that I’m doing right now, which is speech, and also aids in swallowing and mastication, which is a fancy word for chewing.
Now, what we’re seeing right now on the screen is an image of a section of the tongue and we’re looking at it from a left lateral view. And, also this image we’re going to be looking at it throughout this tutorial, which is a coronal section of the tongue, as you can see here, we’re cutting the tongue and looking at it from an anterior view. You see here the hyoid bone and the different blood vessels and nerves that we’re going to be talking about.
We’re going to start off with this image here of this highlight, highlight in green, which is highlighting then the external carotid artery which arises from the common carotid artery. And the external carotid artery gives off branches that extend to the neck of the mandible including the lingual artery. And right now, you can also see here from this anterior view of the coronal section of the tongue, you still see here a green highlight which is the external carotid artery.
The next one is one of the branches that we just talked about which is the lingual artery, which you see now highlighted in green. Now, the lingual artery is a branch of the external carotid artery and it enters the tongue deep to the hypoglossus muscle, which is this muscle here that you see cut so we can then expose the lingual artery. The lingual artery will be giving off several branches that supply the tongue.
One of them we’re going to be highlighting now which is the dorsal lingual artery and you see a little bit here, the highlight coming off of the lingual artery. Now, the dorsal lingual artery is a branch of the lingual artery that is comprised of 2-3 branches. Now, this artery will be supplying the base of the tongue.
Another branch of the lingual artery is this one that you see here now highlighted which is the deep lingual artery. Now, this one runs between the genioglossus muscle and the inferior longitudinal muscles of the tongue. Now, this artery runs to then the apex or the tip of the tongue as you can see here.
The next branch that we’re going to be highlighting, next artery, is also a branch of the lingual artery, the sublingual artery that runs between the mylohyoid muscle and the sublingual gland. The sublingual artery will be extending to the gingiva and gives off branches to the sublingual gland.
We’re going to move on and talk about now veins and we’re highlighting one in green, the important vein here, which is the internal jugular vein. The internal jugular vein and its tributaries drain the tongue and extends from the jugular foramen to the venous angle.
Another vein that we’re going to be seeing here highlighted in green is known as the deep lingual vein which as you can see here on this image runs along the deep lingual artery and this vein drains the tongue into the internal jugular vein.
The next vein that we’re going to be highlighting now, you see a little bit of a highlight here, which is the dorsal lingual vein. Now, the dorsal lingual veins also drain the tongue and they are comprised of a number of veins from the dorsum of the tongue and, as such, they drained the back of the tongue.
The next vein that we’re going to be highlighting here is known as the vena comitans of the hypoglossal nerve or also known as the comitans vein of the hypoglossal nerve, and this one runs inferiorly along this nerve here which we will be talking about, hence, the name, the hypoglossal nerve. Now, this vein will be draining the tongue and it will also be draining into the lingual vein.
The next structure I would like to highlight here is also a vein but you see a little cut here, I would like to also highlight here which is the retromandibular vein. The retromandibular vein drains into the facial vein and then into the jugular vein. It is sometimes referred to as the posterior facial vein because as you can see here, the next highlight, this is a cut of then the facial vein. Now, the facial vein drains into the internal jugular vein but in some cases it has been seen to join with the retromandibular vein as well. So, there are a few variations, and it courses beneath the region of the submandibular gland and has several tributaries before it drains into the internal vein.
We’re going to move on to the different nerves of the tongue and, before we do so, I would like to highlight here on this slide that the tongue is innervated by the peripheral nervous system. So, let’s start looking at our first nerve here, one that I talked about before. This is the hypoglossal nerve. Now, the hypoglossal nerve is also known as the 12th cranial nerve and it innervates the intrinsic muscles of the tongue as well as the hyoglossus, the styloglossus and the genioglossus muscles. Now, the hypoglossal nerve provides motor innervation to all the intrinsic and extrinsic muscles of the tongue with the exception of the palatoglossus muscle. Now, the motoric branches of the hypoglossal nerve innervate both the anterior 2/3 and the posterior 2/3 of the tongue. And if we move on here to this image you can see the nerve from the anterior view of this coronal section, you can still see here the hypoglossal nerve highlighted in green.
The next nerve that I would like to highlight here on this image in green is known as the lingual nerve. This is a branch of the trigeminal nerves mandibular branch. This nerve gives off sensory branches that provides sensory innervation to the anterior 2/3 of the tongue.
The next structure that we’re going to be highlighting here, which in this image has a similar shape as a spider, it looks like a tiny spider. So, for those who fears spiders I suggest you do your best to stay tuned for this last topic which is, this last structure, is the submandibular ganglion. Now, this is located on the hypoglossus muscle. This is a parasympathetic ganglion where the preganglionic fibers of the chorda tympani will be synapsing with the postganglionic fibers of the sublingual and submandibular glands. And remember this that the chorda tympani is a sensory branch of the facial nerve.