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Good evening everyone. Um Thank you so much for joining us for our second uh webinar session on the MRC S Dissected Series before we crack on. Could I just confirm everyone can hear us clearly? I just wanna see that we are alive. You can hear me right? I can hear you. Fine, perfect. Um Right. So let's give it a couple more minutes um Before we crack on in the meantime, for those of you who have joined us uh today. Um Do you wanna share your med sort of code in the chat so people can sort of uh you know, begin logging in? Yeah, sure. So um so you mean meter, right? Sorry. Yeah, meter go. Yeah. So um for this er talk, I've done a few quiz questions um just to keep it interesting. Um gonna use ment. Um So the code is one second just sharing it. I've just shared the uh ment meter link. So if you click on that and you join the code, you can access the uh online quiz as well. Um So yeah, over to, right. So um thanks everyone for joining. Um My name's I'm one of the class esteemed, um, corps trainees in the northeast. I've, um, sat and passed, er, part A and part B, um, around a year and a half ago. And I've been asked by, um, N STC to do a talk on head and neck anatomy. It's really difficult to, uh, cover all of head and neck within one or 45 to 50 minute time slot because there's just so much that they can ask. So for those of you revising for part A or part B, um although my lecture hopefully will be valuable to you. It's not, it's only around 30 to 40% of the anatomy that they could ask. But what I've tried to do is um to cover the most sort of important topics that come up. Um And along the way, I'll tell you sort of what else that you should be thinking of when you structure your vision. So who's everyone logged into um mentor meter? Can you just put in the chat if you're struggling or need a little bit more time, we can give you another 30 more seconds. Ok, fine. So hopefully all of you are logged into um ment meter. Um And that's sort of the method I'm gonna be using um in this teaching session. So, what are the learning outcomes? So we're gonna try to gain an understanding of common anatomy topics tested in the head and neck section of the MRC S syllabus through er MC Qs to keep it interesting, like I mentioned previously, it's impossible to cover all of head and neck within 45 minutes. Um So I'm gonna give you sort of an overview of the main topics that they could potentially ask. But like I said, um there are so, so many topics and at the end of the talk, I'll give you some resources that will contain all the topics that you need for, for head and neck. Um We're gonna make this as interactive as possible. Um So I was originally gonna use sliding, but then I changed the meter which you've all got the code for. Um And throughout the the revisions session, I'll provide some explanations to form a basis for further structuring your revision, right? So first things first. So question one, the internal auditory meatus pierces, the surface of which bone and I'll give you guys about a minute to answer this. Yes. So any more answers or need to be answered so far? No. OK, good. So for those of you who answered the uh temporal bone, you're absolutely correct. Um The internal ultra meatus does indeed pierce a temporal bone. So that brings us on to our first topic. And the first thing that you should be um learning for your exam, whether that's part A and part B is uh the cranial fossa which can be split into anterior, middle and posterior. Um for the purpose of this slide, we're gonna focus on the posterior cranial fossa which is bordered posteriorly um by the squamous process of the occipital bone anteriorly by the petrous part of the temporal bone and the er clivus as well of the sphenoid bone. It contains several foramen. Um So it contains a jugular foramen, the hypoglossal canal foramen magnum, the clivus and the internal acoustic meatus. Um which is the was the answer to our um which contains a facial nerve, the SIBO cochlear nerve and the labyrinthine artery. The labyrinthine artery is a branch of the anterior inferior cerebellar artery, which comes off the bacillar artery. So what's really important is that you learn the er borders of each cranial fossa. Um You learn the foramen involved in this cranial fossa. Um But something that at the top tip that I would advise is learn what the foramen looked like from the other side as well. So if it is, if you're looking from the skull upwards, I um haven't got a picture in this slide. Um But sometimes in the exam, they can turn the skull around and ask you to label the foramen from the other side, which can confuse quite a few candidates. But no, in this, um in this example, I've just got um the foreman of the posterior cranial fossa, um which is a Foramen magnum. That's the biggest one. It contains a medulla oblongata, the brainstem. Um the jugular foramen which contains cranial nerves 910 and 11 as well as a um internal jugular vein, the hypoglossal canal, um which contains the, er, or the hypoglossal nerve runs through internal acoustic meatus, which I've already said. And then the clivus as well. Now, you might think the clivus in this scenario is ir irrelevant. Um, but it's actually some, uh, a question that comes up, they'll ask you to um, recognize it on the skull and ask you what passes over it, um, or on top of it. And the answer is cranial nerve number six, right? Ok. So um question two. So an elderly male smoker attends to the clinic with a three month history of a hoarse voice. You proceed to examine his larynx with a fine nasal endoscopy or F ne so that you can visualize vocal cord abduction. The question is what muscle, what pair of muscle um abducts the vocal cords and I'll just put the, so you've got a good range of answers there, which is good. I think four of you have gone for C Aroid. I'll give you another 20 more seconds any more answers. Nope. Right. So, um well done for those of you who answered correctly, the answer is um posterior er crico retinoids. So, um vocal cord muscles are really difficult to learn and it took me quite a few attempts um to memorize exactly what goes on. Um And what does, what I think if you're really struggling with the movement of the vocal cords, the most important thing to remember in this topic is that there's only one muscle that abducts the vocal cords, um the rest adduct and one tightens. So the posterior crico retinoids are the only muscle pairing that abduct the vocal cords and or open the space between the the vocal cords. The other muscles such as the lateral crico retinoid, they abduct the vocal folds, the transverse retinoid muscles also adduct the vocal vocal folds and the cricothyroid muscles um tighten the vocal folds. So, movement of the vocal folds, um muscles involved is a commonly tested topic. So I strongly advise you to um revise this. Um but the, the most important thing is that the only muscle to abduct, the, the vocal cords is a posterior crico a retinoid. And it's to do with the movement of the vocal of the muscles on the retinoids rather than on the vocal folds um themselves. So the retinoids um will move sort of rotate on themselves on due to the actions of the muscle. And what that will do is either lengthen and er abduct or abduct the vocal cords, changing the picture of the sound that you're able to make. Um I another important thing on this slide is the nerve supply. So all muscles apart from the cricothyroid muscle are supplied by the um recurrent laryngeal nerve. And that's really important to, to, to memorize. So, the recur recurrent laryngeal nerve is um one of the distal branches of the vagus nerve. Um the right, it's the only sort of nerve pairing that has asymmetry between the right and left. Um So the left recurrent laryngeal nerve um will loop around the aortic arch. Um but the right recurrent laryngeal nerve won't. Um So the recurrent laryngeal nerve um supplies all the muscles of the vocal cord apart from the, the cricothyroid. So usually in the exams, they try to trick you out. Um Just remember that the cricothyroid muscle is the only muscle um, of the vocal cords that's supplied by the superior laryngeal nerve, not the recurrent laryngeal. And you might get a question, um, saying that, um, you know, a, a patient's had a thyroidectomy or a parathyroidectomy, they're now unable to make high pitched sounds. Um And if you see that, then the answer is they've lost function of the superior laryngeal nerve because it supplies the cricothyroid, which is involved in tightening the, the vocal folds. Another er, exam scenario that comes up, um, either in part A or, or part B um, will be, um, what happens if you have unilateral recurrent laryngeal nerve palsy. Um, and the answer to that is a patient will present with hoarse voice, but if they present with bilateral recurrent laryngeal nerve palsy, that's uh a, a medical emergency because they lose the ability to abduct the vocal folds. The rema Gotti remains closed and they're unable to, to breathe. So that's a medical emergency. All right next question. OK. So a bit of a tricky question now. Um and I'll just load it on a meter. So um the stapes is derived from which embryological structure. So two of you are motivated for the second pharyngeal arch. One for the pouch fall from the arch. OK? You got a nice um spread of answers, which is good. I'll give you guys another 20 more seconds for those you have in um you haven't waited yet. All right, another 10 more seconds. OK. So the correct answer is, oh, some of you still waiting. OK. So, d one second, my centimeter is frozen. OK. So my ment meters frozen, I don't know why, but for those of you who voted the second er pharyngeal arch, you're correct. Um That's the, that's the correct answer. So, um a very, very tricky concept in um MRC S in part A and part B and it's something that's um tested more in part A rather than part B. Um But something to know about nonetheless. So, um in embryological development, we have uh arches um and pouches. So you can see in the diagram in the left, um the circular structures um represent the arches. So you have the first arch, second arch, arch, third arch, and then you've got arches 4 to 6 at the bottom. The fifth arch um does exist, but it tends to degenerate very, very early on um during embryogenesis leaving you with 1 to 3 and then um 4 to 6. Now, importantly, each arch contains cartilage, um muscles and uh a nerve as well that originates from the arch. The pouches are what are represented as the v shapes within, in between the arches. So, um there are the pouches and there are six pouches in total. So it's really important not to get confused between the, the arches and pouches. Now learning what comes from what uh what um is derived from the arches and pouches can be quite um difficult. Um So I've just put on the right hand side, a table that's there um to help you. And this is how I um re revise it for my part, a exam. So the first arch um gives rise to everything beginning with m. So when we talk about cartilage, we WW we talk about the maxillary process and the mandibular process, um the malleus and incus uh as part of the middle ear. So anything beginning with, when we talk about the muscles um aligning with our theme of M, we have the muscles of, of mastication. So, apart from the temporalis, we have the mater um medial pterygoid, but we also have the mylohyoid as well um as well as the anterior belly of digastric um which is a, a little bit of anomaly. But if you guys remember just all the muscles beginning with m um you won't be too far off again with nerves. Um The way I II remember it is. Um So what's innervates the muscles of mastication, which is the a mandibular nerve of the trigeminal. Um But also you've got the Maxillary division as well. So you've got the MV two and V three divisions when we talk about the um second arch. Um Again, the way I remember it is anything beginning with s so again, as part of the inner ear, we up middle ear, we've got the stabs, we've got the styloid process, um the stylohyoid ligament and then we've got the muscles of facial expression or the muscles that help us smile with an S we've also got the stylohyoid platysma and the posterior belly of the po posterior belly of the digastric, which again is a little bit of anomaly. Um So the muscles of facial expression arise from the second arch. Um and the muscle uh and the nerve um responsible for innervating the muscles of facial expression is the cranial nerve. Number seven, the facial nerve. So that's the nerve that comes from the second arch. We then have the, the third arch, which I remember was anything to do with a pharyngeus ending. So the cartilage again is a little bit of anomaly. Um You've got the stylopharyngeus. Uh and then in terms, that's the only muscle that comes from the, the third arch. Um In terms of the nerve, again, we've got pharyngeal. So we've got the glossopharyngeal er nerve. Last, we've got arches, um 4 to 6. Um And again, this can be quite difficult to remember, but the way I did it for my exam was um I remembered it as um actors act and act, swallow and speak. So in terms of the cartilage, you've got the uh retinoids that form part of the, the vocal cords. You've got the cryo cord cartilage for c um corniculate and cuneiform, which are two small bits of cartilage that sit on the top of the uh arenoid. And then you've also got the thyroid as well. Um And sometimes that can catch a few people out because they think that the thyroid should arise from um one of the pouches, but it doesn't in terms of the uh the, the muscles, um the fourth arch, we've got all of the pharyngeal constrictors and then the sth arch contains all the intrinsic muscles of the larynx. Then, in terms of the nerves. So, um simply swallow. Um that's the superior laryngeal branch of the vagus nerve. The reason why it's simply swallow is because if you damage this branch, um you won't be able to swallow properly or you won't have the, the, you won't have a proper swallow. Um And you'll most likely choke. Um cos it's involved in both the swallowing reflex and the coughing reflex as well. Then you've got the recurrent laryngeal branch from arch number six as well. Um And that's uh again, as mentioned in a previous slide that innervates all the muscles of the, um, the vocal cords, apart from the corot theroid, and that's involved in speaking. So that's how, ii remember it in terms of the pharyngeal pouches, um, you've got six pharyngeal pouches. Um, they don't tend to really ask. In fact, I've never seen them ask or heard of them asking about 12, pouches, one and two. What they do tend to ask is 34 and five and six as well. So it can be a little bit confusing. So the third pharyngeal pouch gives actually gives rise to the inferior parathyroid glands as well as the thymus. Um where the fourth pharyngeal pouch gives rise to the superior parathyroid glands. Sometimes it can be um candidates can get confused. Um and they'll say that the superior ones arise from the third and the inferior arise from the fourth, but that's actually the, the other way round when I had my exam. Um they actually asked me about the thymus um rather than any of the, the parathyroid glands. Um So it's just important to remember that that tags along. I in the third pharyngeal pouch, the 5th and 6th, pharyngeal pouch produce a parafollicular c cell. So that again, that's important to remember, right. Let me see if I can just get a centimeter back on. Ok. So, um next question is which of the following is directly related to the mandible. I give you guys about a minute to, to, to answer this one. Ok. Another 20 more seconds. So most of you have gone for lingual nerve behind that is a lingual artery. Ok. 10 more seconds. Ok. All right. So well done for those who said um lingual nerve, right? So, um lingual nerve is um one of the many nerves that are tested in um uh MRC S syllabus, but it's probably the most popular one because of its um functions. So it's a subbranch of the mandibular nerve, um V three or the V three of the trigeminal nerve. Once it exits um the foramen, it divides into the inferior alveolar nerve er and the the, the lingual nerve, er the lingual nerve is involved in um providing general sensory um innervation to anterior two thirds of the tongue. But the reason why the examiners like to test it because it also has special sensory. So it will provide taste um via the chin party to the, to the anterior 2000 of the tongue as well in terms of uh glands that it innovates. So it innervates uh the sub, the submandibular and subli glands as well. And um if we look at some of the relations of the lingual nerve, so it actually exits the foramen um and passes er in between the tensor vela palatini and the lateral pterygoid um to pass just inside uh of the mandible um where it passes then in between the myeloid and the high, higher glossus to then go on and innovate the tongue. But if you get a question, asking, what's the um sort of nerve related to the mandible? The answer most commonly is the, the, the lingual nerve. Right. Right. So, back to um menter then. Ok. So moving on to um some vasculature. So which of the following is a branch of the external carotid artery. So most of you've gone for occipital artery, give you about 20 more seconds. So, one of you lacrimal. Ok. So the correct answer is um occipital uh artery. So, well, then most of you guys have got it correct. One of you answered after the tick went up. Um So why can't it be the other? So, the inferior uh inferior thyroid artery is a branch of the thyroid cervical trunk, which in turn branches from the subclavian. So it can't be that answer. The lacrimal artery is a branch of the ophthalmic artery, which is a branch of the internal internal carotid artery. The thyroid cervical trunk um is a branch of the first part of the subclavian. And er the vertebral artery again is a branch of the first part of the subclavian, leaving the occipital an er artery is the only answer. So, um the most important take home message with the external carotid artery is um probably the, the, the um acronym that I use to, to remember it. So I like to remember. It is some attendings er or some anatomists like freaking out potential medical students. Um So we have um s for superior thyroid artery, we have a for ascending pharyngeal, we have L for the lingual artery. We have F for the facial artery. We have O for the occipital artery, which was the answer to our question. P for the posterior auricular m for the maxillary artery and um s for the superficial temporal. Now, the most important branch probably from the external carotid is the maxillary artery. And the reason why it's the most important is because it gives rise to the middle meningeal artery. So that um so middle meningeal artery um is a branch of the maxillary artery, not the external carotid. Now, um the o the occipital artery and the superficial temporal artery actually form a really dense anastomotic network uh around the skull, which is why if any of you had surgical jobs, if you've seen a patient down in Ed, who's had a scalp laceration, um they tend to bleed quite a lot because of this dense anastomotic network, uh particularly because the way the muscles create the, the, the the gaps in the, create the lacerations wider as well. Um They do tend to bleed quite a lot to this due to this anastomotic network. So you guys just remember some attendings or anatomists like freaking out potential medical students and you, you won't go wrong. OK. So um next question then um we've got which of the following structures is found in the posterior triangle of the neck. Mhm About 10 more seconds. I think all of you have gone for the for one answer, which is good. Yes. OK. Good. So um the right answer is um accessory nerve. So you guys all got that right? Which is really good. Um I just put my slides back on. Oh, just loading my slides back up. OK. OK. So, yeah, So um posterior triangle triangle of the neck is uh the borders are the middle third of the clavicle, the posterior border of the sternocleidomastoid and the anterior border of the trapezius. Now, although I've covered posterior triangle in this teaching session. Um The examiners could ask about any of the anti uh any of the posterior uh any components of the posterior triangle or components of the anterior triangle which are split up into further and smaller triangles which will cover later. So the posterior triangle um is made up of the subclavian triangle, er and the occipital triangle. Um And the border between those two is the er omohyoid muscle. The um base of the posterior triangle is the um neck muscle. So you've got the anterior medi medial scaling as well as elevator scapula as well. It's really important to know what the contents of uh contents are within each triangle. Um So for this slide, we've got the posterior triangle and I split it up into vessels and, and nerves. So, in terms of the vessels, uh we have the third part of the subclavian artery, which doesn't have any branches. Um, we've got the subclavian vein and we've also got the external jugular vein as well in terms of the nerve. Um, like I've tested in the question, we've got the accessory nerve. So a common exam question might be a patient's been stabbed um in the neck and they might give you a diagram, Er, and they might say that the patient is now unable to um shrug their shoulders. And the answer is because they've damaged their accessory nerve which runs in the posterior triangle. You also have um um some of the branches of the cervical flex, er cervical plexus. So we have the, the fren nerve as well. That's another important branch that often gets missed and we've got trunk of the brachial plexus as well. So a another exam question might be and this may be might be more geared towards. Part B is uh a patient again, is stabbed in the neck in the neck and presents with symptoms of of herbs, palsy. So, an adducted um an adducted um forearm, abducted arm, um with a in a waiter's tip position. It's because they've damaged the trunks of their brachial plexus. So a lot of important vessels um and nerves within uh the posterior triangle. Um but the most important of the vessel is a third part of the subclavian artery, the external jugular vein. And in terms of the, the nerves, you've got the accessory nerve, um, the phrenic nerve and the trunk of the brachial plexus. I would also, um I didn't uh have a chance to put it in this presentation but also learn the fascial sheaths um that are contained in the neck. So for example, the, the carotid sheath which contains the, um the common carotid artery, um the internal uh internal jugular vein and the vagus nerve. But you've also got other fascial sheets as well such as the, the prevertebral fascia, investing fascia. Um because that's something that they could, they could ask about. Yeah. Right. Um Next question then um OK. So a patient undergoes left sub submandibular gland surgery. His hypoglossal nerve becomes injured in the process. What is the most likely outcome? I'm gonna give you guys about a minute to answer this. So all have you gone for one answer so far? So give you guys about 15 more seconds and then, OK, so um the correct answer is the two of you who voted for all extrinsic muscles of the left side of the tongue, except the palatoglossus will be paralyzed. So, um the nu so why is it? So one of you voted for numbness to the posterior third of the tongue. So I'd like to see in, in the next slide, the posterior third of the tongue is supplied by the glossopharyngeal nerve. Um In this question, the, the hypoglossal nerve is, is, is injured. Um, so we wouldn't get, uh, numbness to the posterior third of the tongue. None of you voted for the uvula. Um, which is good if the uvea uvula deviates to the left, we, er, suspect a vagus nerve injury on the contralateral side. So we would be expecting a right vagus nerve injury. Um, the genioglossus muscle is spared. No, that's not the correct answer because the hypoglossal nerve actually supplies the genioglossus on protruding the tongue, um on protruding the tongue, deviates to the right. I can see why you guys answered that. Um And that would have been my first answer as well, but actually weirdly with the tongue, the, the tongue always deviates to the side of the injury due to the strength of the contralateral muscles. So, the correct answer is actually um the three of you who voted for all extrinsic muscles of the left side of the tongue, except the platyglossa are, are, are paralyzed. Ok. So when it comes to the tongue, um so again, all the muscles of the tongue are innervated by the hypoglossal nerve, apart from the plateau glossus, which is the only tongue muscle that's innervated by the vagus nerve. Now, there are um 44 extrinsic muscles that you need to know about. You've got the styloglossus which er originates from the sty um the styloid process and comes down to form the uh underneath the base of the tongue that's involved in retraction of the tongue. You've got the hyoglossus, which is a fan shaped muscle, it's the largest tongue muscle. Um and that's involved in protrusion um and depression of the tongue. You've got the genioglossus which is involved in protraction of the tongue. And then you've also got the plate glossus, which is innervated by the va the vagus nerve. You've then got intrinsic muscles of the tongue as well that you need to know about. Um although less importantly than extrinsic muscles. Again, all the intrinsic muscles are supplied um by the um er g er the hypoglossal nerve. So you've got superior longitudinal, vertical, transverse um and then the inferior longitudinal as well. So you've got longitudinal, vertical and, and transverse as well as extrinsic muscles. So you've probably seen this diagram um since medical school, um it's really important because it just keeps coming up and I guarantee it will be tested um in your exam. So, er on the right, we have motor. So we can see that all of the muscles of the tongue uh apart from the palatoglossus are supplied by the er hypoglossal nerve. On the left, we have sensory nerves which can be a little bit confusing because cos you have um normal sensory. Um so, so for example, pain and temperature, but then we also have um special sensory, which is our taste. So um if, if we start with the easiest one at the back of the tongue So the posterior third, both um taste and normal sensation is supplied by one nerve, which is a glossopharyngeal. So that's easy to remember. It comes in the anterior two thirds. Um So er the sensory nerve is er supplied by the L is the sensory, the sensation is supplied by the lingual nerve um which is cranial nerve. Number five comes off the mandibular branch, um mandibular nerve and then we've got um special sensation of the corda tympani er which actually arises from the from cranial nerve. Number se number seven in the facial nerve. So there's a lot of nerves going uh on here. So it's important to remember the difference. So, posterior third um is the glossopharyngeal anterior third for normal sensation is a lingual nerve, which is a branch of cranial nerve. Number five and special, special sensation is a corda tympani um which is a branch of cranial nerve. Number seven, right? Um Question eight, we've got. Yes. So within the orbital socket, there are three main for foramina, the superior sof stands for superior orbital fissure. IO F stands for inferior orbital fissure and O EC stands for the optic canal, which of the following enters through the optic canal. O ec I give you guys about a minute to answer this. So one of you gone from the lacrimal nerve about 10 more seconds. OK, good. So those of you who voted the um ophthalmic artery, you're absolutely correct. So, well done. So um the superior orbital fissure again is part of the er middle cranial fossa which is bounded anteriorly by the lesser wings of the sphenoid um laterally by the squamous part of the temporal bone and posteriorly um by the um do um dorsum silica of the sphenoid bone and the petrous part of the temporal bone as well. It contains a superior orbital fissure which contains cranial of 345 A or B1 and cranial number six, as well as the ophthalmic veins, not the ophthalmic arteries. The ophthalmic arteries crucially go out of the optic canal along with the optic nerve. And so ophthalmic arteries was, was the right answer. Um Just because uh I've got quite a few more questions to cover. I'm not gonna go through what um enters through each um foramen um in the middle cranial foa. Um But it's really important to know um again, what, what enters through them and be able to identify them on a model both from looking down in the skull but also looking up as well cos it could turn over the skull and ask you to identify um someone's just said no sound. Is that correct? Can you not hear me? I can hear you on my end. Uh Anyone else having similar issues? Find someone else? No. And I think, sorry cause I think it might be on your end, your end. Yeah, sorry about that. There we go. No worries. Yeah. So that's the middle cranial fossa. OK. So um last couple of questions then, so a 14 year old um presents with the A&E with erythematous swollen tonsils and left ear pain. Ear examination is unremarkable, referred pain from which nerve causes this symptom. So we've got split so far I give you guys another 20 more seconds, got 10 more seconds. Any more answers. OK? So the correct answer is the glossopharyngeal nerve so well done to you. Um whoever, whoever answered that correctly. So, um if we have a look at the glossopharyngeal nerve, so I mentioned the lingual nerve before the glossopharyngeal nerve again, is another nerve that's commonly tested. Um Just has because it has quite a few functions. So it exits the skull through the jugular foramen um to pass anteriorly to the er internal carotid, it then branches off to, to, to do several functions. So in terms of sensory, so it supplies all the middle ear, but it also supplies the tonsils as well or the sensation to the tonsils. Um So which is why when you get tonsil inflammation, you can actually get referred ear pain. Hence the answer to this question in the glossopharyngeal nerve. I don't forget from the, from the image of the tongue as well. It also supplies both sensation to the tongue but also a special taste as well in terms of the muscle. So it only supplies one muscle, which is a stylopharyngeus, all the other intrinsic muscles um, of the larynx are supplied by the vagus nerve and parasympathetic. So it actually um supplies uh the otic ganglion which then goes on to innovate, um the parotid gland and again, that's commonly tested in the exams. And the fibers actually hitchhike on another, another nerve called the uricor nerve, which is a branch of the, er, mandibular nerve of the, of cranial nerve. Number five. So again, it supplies uh the tonsils or sensation to the tonsils, er the middle ear, the posterior tongue, as well as taste, it innervates one muscle and it also supplies the parotid gland as well. Whereas a lingual nerve um which is a branch of cranial nerve. Number five supplies the submandibular sub lingual um glands. Whereas a parotid gland is supplied by the glossopharyngeal AAA com really common exam question. OK. So um penultimate question then uh we have a 72 year old has biopsy confirmed superficial submandibular gland carcinoma, which structure crosses superficial to the submandibular gland. I give you guys about 30 seconds to answer this. Ok. So um whoever answered um the marginal um bra marginal mandibular branch of the facial nerve, um You're absolutely correct. That is the right answer. So, um the submandibular anatomy is quite complex um because it has a superficial and deep branch. So we start by its location. So it's located in the anterior triangle of the neck of the neck or more specifically the submandibular gang. Um triangle, which is bordered posteriorly by the digastric muscle or the posterior belly of the digastric muscle superiorly or um by the angle of the mandible and anteriorly by the anterior belly of the digastric muscle. And that forms a submandibular triangle where you'll find this submandibular gland. Uh Now, as previously mentioned, there's a superficial and deep part to the sub uh submandibular gland and in between both parts, what separates superficial from deep is the er mylohyoid muscle. Now, um if we look at some of the um uh if we look at some of the answers before, so the external carotid artery and the internal jugular vein er are not nowhere near the, well, in terms of an er um proximal relations are not near to the submandibular gland. If we look at the mylohyoid muscle, we know that's in between the superficial and deep. So it can't be the answer in terms of the lingual nerve we have. Um so the, the the three nerves that you need to remember that are around the submandibular gland are the lingual nerve, the er hypoglossal nerve and the marginal mandibular branch of the facial nerve. Now, the lingual nerve actually runs superior to the deep part of the man of the submandibular gland. The hypoglossal nerve lies inferior to the deep part of the submandibular gland. We then have the deep part of the mandibular gland. We then have the myelo hyoid and then we have the superficial part and lying on top of the superficial part of the man of the submandibular gland is the marginal mandibular branch of um the of the facial nerve. So commonly, um when we're doing uh when ent surgeons um are taking out the submandibular gland for a stone, for example, what they'll often do is go around 1 to 2 centimeters below the um where they, where your, you would normally find the submandibular gland in order to avoid damaging the marginal branch of the man, the marginal mandibular branch of the, of the cra of cranial node. Number seven, which actually supplies all the muscles of the lower lip. So it's involved in um frowning, for example, and we can see from the, the, the, the picture on the right um Just how close the marginal mandibular branch of the, of the, the facial nerve is right. So um last question. Um so we done so a lumbar puncture is performed for suspected meningitis. Um CSF is connected to the subarachnoid space to the ventricles um through which of the following. Oh yeah. And I'll give you about 20 seconds to answer this 10 more seconds. Anyone else? OK. So the right answer is the Foramina of MDI and, and, and Luschka, which is absolutely correct and we'll see why in the next slide. So, um so in terms of the CSF pathway, so CSF is actually produced um in the choroid plexus um which is lined by the ependymal cells. Um it then er passes from the lateral ventricles which you can see in red um where the epidermal cells are um into the third ventricle, the blue with the foramen of Munro, once in the foreman of Monro, it then passes into the fourth ventricle via the cerebral aqueduct. And usually if you see, you know, you would have seen in textbooks, Children with non commu non communicating hydrocephalus, that's usually caused by a blockage or a stricture in the cerebral aqueduct, usually by a AAA tumor, for example. And that can cause non communi no non communicating hydrocephalus. From um the fourth ventricle CSF is then released into the subarachnoid space um via the foramen of MDI, which runs in the midline and then laterally um via the foramina of busa um into the roof of the fourth ventricle. It then um passes down um before being reabsorbed um into the duo venous sinuses through the subarachnoid cys which are almost like small out pouches um in um from the subarachnoid space um into the duo venous sinuses for the CSF to to become reabsorbed. So well done. Who you, for those of you who got that right? The most important thing you need to remember in this slide is cerebral aqueduct, er non communicating hydrocephalus. Um as well as how CSF moved into the subarachnoid space through the foramina MDI um and the foramina lush as well, so well done, right? So, um thank you so much. That's the, er, end of the teaching session. Um It was uh a very quick overview of some of the, er, important topics um of the MRC S syllabus for head and neck. Um I wasn't able to cover um, all of the topics. There are loads more topics than that. Um for example, duo venous sinuses, I didn't cover, um I didn't cover the um uh some of the other cranial nerves as well. The anterior cranial fossa, these are things that and the anterior triangles of the neck. Um These are some of the more common topics that also come up as well. But what I try to do is give you um an example of what could come up in, in your exams. So, um I put some resources on there, which I found really good when I was revising for my exams. Um So the first is um Alan's anatomy and I've put them in order of, of what I think you should go through first. So I would start with Akin's Anatomy if you still have access to this. Um So for mine, I um luckily still had access from my medical student days. Um So I watched all of the anatomy videos on Akin's er Can Akins um on the Atkins website. It's really good, it goes over um all the muscles, ligaments, tendons, nerves in so much depth, um giving you a really good visualization and I would strongly recommend this over er, an Atlas book. Um So if you can get access to this, it, it would be really great and, and beneficial and I use this for part A and part B. Um The second symbol is for teaching me anatomy, which I used alongside Acklin and used to make this um powerpoint as well. Um Teaching me anatomy is always good. It gives you a really succinct succinct overview and if you need to find something quickly, um it can be really, really useful for this. The third is a resource that not many people know about. Um, but I think it's a hidden gem. Um, you can either get the book version um because I like annotating, um, or their online website is really good as well. Um, it's all, er, animated or it's all sort of color coded um, pictures. Er, it's really good for learning, er, cranial nerves. It's really good for learning. Um, um, lymph nodes, it's really good for learning um vasculature as well. It's a, it's a really underrated book and website and I, and I really strongly er, recommend it alongside Atkin's, er, Atlas lastly. Um, I used the, er, the book in Green, um, when I thought I'd learnt all my anatomy as in the run up to exams, it's a um, really useful um, book for testing your knowledge of anatomy. So it'll give you pictures of different specimens and ask you to, to label um, to label what each specimen shows in individual muscles, tendons, nerves, et cetera. And I found that a lot of the images in here, um, or a lot of the specimens or a lot of what they were asking you to label, um, actually came up in my part B exam. So it's a really, really good um, textbook er, to use right at the end. Um, if you want to test yourself. So, um, thank you, er, very much. If you've got any questions, just pop them in the chat and I'll try to answer them and then I'd appreciate if you could scan the, um, er, feedback code just to provide some feedback for, for sessions and how to.