Arteries and veins of the parapharyngeal space.
Hello, everyone. This is Joao from Kenhub and welcome to another anatomy tutorial where this time I'm going to be talking about the parapharyngeal space, specifically the different blood vessels that we find in this region.
And right now, we’re looking at an image where we see the back or the dorsal view of the neck specifically, the pharynx where we see the different pharyngeal blood vessels, arteries, and veins. And we’re going to be describing all these structures that you see here.
Now the first thing we’re going to be doing here on this tutorial is describing the different arteries that you find here on this image.
And that includes the brachiocephalic trunk, the common carotid, the external carotid, the superior thyroid, superior laryngeal, the occipital artery, ascending pharyngeal artery, and also we’re going to be seeing the internal carotid, the thyrocervical trunk, and finally the inferior thyroid.
Let’s start off with the very first one on the list that you see now highlighted in green on this image. This is known as the brachiocephalic trunk. You can also call it the brachiocephalic artery. And this is an artery of the mediastinum.
The brachiocephalic trunk is the first branch of this structure here which is known as the aortic arch. As you can also see how it branches out of this aortic arch. And soon after it emerges, the brachiocephalic artery will be dividing into two other arteries including the common carotid artery which you see here.
So the right common carotid artery because we are looking at the dorsal view of the neck. So this is if we’re looking at the back someone’s neck. And this will be then the right common carotid artery.
The other branch of the brachiocephalic trunk will be then this one here which is the right subclavian artery.
The brachiocephalic trunk will be then supplying blood to the right arm and the head and neck. Very important thing to notice here on this image that there is no brachiocephalic trunk on the left side, so what you have here is a branch coming out of the aortic arch which is then the left common carotid artery and this one here which is the left subclavian artery.
So it is time for us to move on about these two structures that you see here highlighted in green which are known as the common carotid arteries.
Now, the common carotid arteries are a paired, they are paired structures which mean that they are two in your body, so two on each side of your neck, one for each half of course.
Then the left and right, as you can see here, left and right common carotid arteries follow the same course with the exception of their origins.
So the right common carotid will be coming from the brachiocephalic trunk as we talked about before. While the left common carotid artery as you can see here and as I talked about the previous slide, it’s branching out of this arch here, the aortic arch.
The common carotid arteries will be then further dividing into two other important arteries of the head and neck, the external carotid artery and the internal carotid artery.
And you can also see them here on this image. This one here found a bit more posteriorly, this are known as the internal carotid arteries.
And then you could see it here, the external carotid arteries also branching off of the common carotid arteries and then going a bit further laterally or their going to be supplying some of the structures of the head.
The common carotid arteries are going to be then supplying different structures of the head and neck.
Moving on to the next structures and highlighting them, I talked about these already. These are the external carotid arteries. One on each side of your neck as you can see here.
Now, the external carotid arteries are major arteries of the head and neck and they arise from those arteries that we talked about before the common carotid arteries.
Now, they rapidly diminish in size in its course up of the neck going to the number and large size of branches given off from them. Now the wall of the pharynx is located medially to them.
Now, the external carotid arteries are going to give off numerous branches which will be supplying blood to portions of the head such as the face, scalp, skull, and meninges. And also the thyroid, larynx, salivary glands, and the tongue are going to be supplied by the external carotid arteries.
Next blood vessels that we’re going to be covering now, we’re going from the back of your neck to the front. So this is the anterior view where we can see clearly the superior thyroid arteries highlighted in green. One on each side of the neck as you can see here.
Now, as you also see from this image, these arteries are arising from the external carotid arteries. So these are the external carotid arteries.
These are the internal carotid arteries as you can see from both sides. And they are branches of these here which you can see now from the anterior view. These are the common carotid arteries.
Superior carotid arteries are going to be anastomosing with each other, so they meet here in the middle, they form this connection as you can see here, and also with the inferior thyroid arteries.
We’re moving again to the posterior view or dorsal view where we can see the superior thyroid arteries highlighted in green. The superior thyroid artery is going to be distributing twigs to adjacent muscles and numerous branches to the thyroid gland.
Now, the branches to the gland are generally two in number. And you can also see here the thyroid gland. Besides the arteries distributed to the muscles and to the thyroid gland, the branches of the superior thyroid arteries are the hyoid artery, the sternocleidomastoid artery, the superior laryngeal, and the cricothyroid artery.
The next arteries that we’re going to be talking about that you see here highlighted in green, I removed a few structures here to then expose this structure that you might know. This is the larynx.
And you can see here then this artery piercing the larynx where you see then the highlighted superior laryngeal artery on this image.
We’re still looking at it from a posterior view. You can also see here the mandible and the sternocleidomastoid muscles. So you can have a bit of location and here the tongue.
Now, the superior laryngeal arteries are branching off if you can see here the superior thyroid arteries. And they will be forming a connection or anastomosis with the branch opposite from the opposite sides. So as you can see here, on both sides you have a superior laryngeal artery, and they’re forming this anastomosis here.
As we transition to this image here where you can see the different pharyngeal muscles cut open. So you can expose the larynx and we can see here different structures including some nerves and veins, but you can still see the highlighted superior laryngeal arteries.
What I would like to add here is that the superior lanryngeal arteries will be supplying muscles, mucus membrane, and glands of the larynx.
The next structures that we’re going to be talking about, next arteries that you see here highlighted in green, these are known as the occipital arteries.
Now, these will be arising from the external carotid arteries. Their branches will be anastosmosing or forming connections with the posterior auricular artery and the superficial temporal artery.
The occipital arteries will be supplying blood to the back of the scalp, and the sternocleidomastoid muscle, and also the deep muscles of the back and neck.
We’re moving on to another image here, we’re going to be highlighting different structures. These are known now as the ascending pharyngeal arteries.
Now, these are the smallest branch of the external carotid arteries. They are long, slender vessels deeply seated in the neck beneath the other branches of the external carotid. This artery will be also dividing into the pharyngeal trunk and the neuromeningeal trunk.
When it comes to the blood supply associated to these trunks. The pharyngeal trunk will be supplying or it actually consists of several branches which supply the middle and pharyngeal constrictor muscles as well as the stylopharyngeus muscle.
While the neuromeningeal trunk will be then supplying regional meningeal structures as well as neurostructures.
We’re moving on to these that you see here highlighted in green which we talked about on previous slides. If you remember one second, if you can remember, yes, these are the internal carotid arteries, branches of the common carotid arteries.
Now, these are major arteries, paired arteries, that you find on each side of the head and neck, the internal carotid arteries will be then supplying the brain. So as you can see very important structures.
And we’re now ready to move on to the next arteries that you see here highlighted in green. These are known as the thyrocervical trunks.
They are branches of the subclavian arteries as you can see here. Now what we did on this image is a zoom of that previous image on the dorsal view. And you can still see here the aortic arch.
Now, they arise from the first portions of the subclavian arteries. Now, the thyrocervical trunks, they are short and thick vessels; and they divide soon after their origin into four branches.
These four branches include the inferior thyroid artery, the suprascapular artery, the ascending cervical artery, and the transverse cervical artery.
We’re going to talk about one of the arteries that you found on that list, one of the branches of the thyrocervical trunk. These highlighted are the inferior thyroid arteries.
They’re found in your neck region. They arise from the thyrocervical trunk as I mentioned before and will be forming connections or anastomoses with the superior thyroid artery and with the corresponding artery on the opposite side.
As you can see here on the image, the inferior thyroid arteries are going to be supplying this structure here, the thyroid gland. We talked about all the arteries that you can see here on this image to move on and talk about these blue structures that you see now on the screen. These are the veins.
Now a quick list of the different veins that we’re going to be talking about on this tutorial, we’re going to see the pharyngeal veins, the internal jugular, the superior bulb of the jugular vein, and the superior laryngeal vein.
Let’s start off with the very first ones on the list that you see here highlighted in green. All of these structures are known collectively as the pharyngeal veins.
Now, they begin in the pharyngeal plexus on the outer surface of the pharynx. And they receive blood from some posterior meningeal veins and the vein of the pterygoid canal.
This blood will be then drained into the internal jugular vein which you can clearly see here on this image. These are the internal jugular veins.
Next veins that we’re going to be highlighting here which I just talked about, these are the internal jugular veins. They are paired veins that collect blood from the brain, the superficial parts of the face, and also the neck.
They also have a common trunk which will drain the anterior branch of the retromandibular vein, the facial vein, and the lingual vein. And after the roof of the neck, it will be draining into the subclavian veins which you see here on the image to form then the brachiocephalic veins.
Next structures that we’re going to be highlighting here, these are known as the superior bulbs of the jugular veins. Now, these structures are dilation at the beginning of these structures that we talked about before, the internal jugular veins.
And you see here then these dilations which are known as the superior bulbs of the jugular vein. They lie in the jugular fossa in the base of the skull.
Moving on to these that you see here highlighted in green, now we remove a few structures again, a few muscles to then expose the larynx and you see now the highlighted structures which are the superior laryngeal veins.
Now, they collect blood from the larynx and then will drain into the superior thyroid veins which you can also see here on this image.