Transcript for:
Overview of Trigeminal Nerve Anatomy and Function

I ninja tears in this video we're going to talk about the trigeminal nerve or the cranial nerve 5 this is probably one of the most important cranial nerves when it comes to sensations like touch pain temperature of the face and a lot of control with the muscles of mastication so for our chewing processes so this is NER we're going to spend a decent amount of time on because it has a lot of clinical correlation with it that can really really really be important that we understand all right so it's going to get started so what are we going to talk about in this video we're basically going to discuss the origin of the nerve where you're going to find in the brainstem okay you're also going to talk about the course of the nerve what are the different branches which there is a plus for branches of this nerve what are the structures that it supplies which is going to be a significant amount of structures and what are those structures do for some of them and then we're going to have a little tidbit on clinical correlation specifically with relationship to is called trigeminal neuralgia alright so let's get started the origin of the nerve is a little bit tricky and the reason why is there's two points that we have to look at you know we have what's called a gangly on how do we define a ganglion a ganglion is basically a group of cell bodies that are located within the peripheral nervous system now here is going to be a special special ganglion and this ganglion here is called the trigeminal ganglion so it has the cell bodies that are going to be very very very important for the actual peripheral processes that are further branches of the trigeminal nerve what are these three peripheral processes coming off one branch is actually going to do what's called the v1 branch know one thing stands for for v1 they actually say this is the ophthalmic division so it's the first division of what cranial nerve five so v1 is the 1st division of the fifth fifth cranial nerve is called the ophthalmic division the second division of the fifth cranial nerve is going to be the maxillary division and then the third division of the fifth cream there where the trigeminal nerve is going to be the mandibular division so again what does v1 here v1 is opthalmic v2 is going to be maxillary and v3 is going to be mandibular okay just that wheel I'm going to refer to them as v1 v2 v3 they might use them interchangeably throughout the process of this video okay so first things first these are the peripheral processes it has to have central processes where did these central processes extend to they extend to the brainstem and they're very very widespread for example these peripheral processes going to come into the brainstem and they could stretch out to three different nuclei what are these three different nuclei well there's a nuclei that's located within the medulla this is probably of all the nuclei here for the trigeminal nerve this is probably the most importance this is called the spinal nucleus of cranial nerve five or the trigeminal nerve okay so it's called the spinal nucleus why is this one so important because it controls so many things you don't know what it controls it controls what's called touch okay pain temperature pressure and even proprioception of the entire face okay so again what is the control touch pain temperature pressure and proprioception of the entire face so whenever these peripheral processes are taking up the sensory information they're bringing it into the actual brain stem to the spinal nucleus of the trigeminal nerve and what kind of fibers are coming to this area touch fibers pain fibers temperature fibers pressure fibers and proprioceptive fibers alright sweet deal another branch could actually go to this actual part here within the pause because you know this is actually going to be what part of the brains and this is the medulla this part here is the pons and this part here is the midbrain or the knees and Cephalon right and that's an important term all right and I'll explain why but the branch here coming to the ponds they call this it's kind of in the center so they can either you have two names for it you can either call it the central or for whatever reason they call it the principal pontine nucleus of cranial nerve five so you can call it the central or the principal pond tiny nucleus of cranial nerve five this one is really important because he's going to be picking up a little bit of touch and proprioception so this guy's picking up what type of sensations he's picking up touch and proprioception okay of the other face particularly of the jaw and this last one up here we said it's within the midbrain okay what else could you call the midbrain you know was actually driving was called the mesencephalon so because it's a part of the maze in Cephalon we actually call this one that the other branches could go to specifically for proprioception and this is for proprioception or pretty much the face this one here is since it's derived from the musing Cephalon this area of the midbrain we call this nucleus B it's a weird one it's called the Mazen cephalic nucleus of cranial nerve five so again the median cephalic nucleus occurring earlier v is picking up proprioception right of the face the central or principle upon tyne nucleus of cranium or five is picking up touch and proprioception from reading the jaw area the spinal nuclear sub tray of the trigeminal nerve is going to be picking up touch pain temperature pressure and proprioception from the entire face now where do these divisions go okay so we know exactly where we can find these origins the multiple nuclei we'll talk about another nuclei right here the trigeminal motor nucleus which supplies the first four in charge we'll talk about that later when we get to the mandibular division but now we're going to do is we're going to talk about this v1 and all the tons of branches it has okay so first off this v1 branch the Soundlink division it's going to move within this nice dural sinuses thorough sinus here called this dural sinuses called the cavernous sinus if you guys have watched the videos on the oculomotor nerve if you guys watched on the abducens and got to sit on the trochlear nerve you guys become very very familiar with this okay so what is it stand for it stands for the cavernous sinus and the cavernous sinus is really important because it's a dural sinus which means if you have to see this brown layer right there that's called the periosteum of the dura mater and this green layer here is branching away from it it's called the meninges of the dura mater that's actually located between that actual between these two structures between the meningeal layer and the periosteal that's where you'll find this cavernous sinus now particularly it actually is going to run within the lateral wall of the cavernous sinus so this v1 division the ophthalmic division is going to move within the lateral wall of the cavernous sinus v2 is also going to move within a lateral wall of the cavernous sinus just below it but v3 he says brick that crap amount and he goes through the foramen ovale alright so now to look at it even better because we're not really giving a justice to look at it from this view really quickly let me say that I actually draw kind of a section here let's say here I have the actual spine bone and then we have here we have the sella turcica and if you know here you'll have like the anterior cleanly processes and you're cleanly processed like this right you know that you have what's called the pituitary gland sitting right here well there's actually going to be a nice little sinus called the cavernous sinus which sits right in this area here sits right in this area and over here you have the lateral walls the lateral walls if you guys remember first one was third cranial nerves then fourth cranial nerve then v1 and the most inferior one is v2 same thing on the other side three for v1 v2 and six is actually moving within the cavity and if you guys remember it's always good to be very very repetitious you what artery is actually coming up through here with the actual six cranial nerve or the abducens service called the internal carotid artery guys remember that the internal carotid artery is moving up through the foramen lacerum and into the cavernous sinus the cavity of it but just so we're clear v1 and v2 are moving within the lateral wall of the cavernous sinus sweet deal as these bad boys move through what happens is I should actually bring the v2 division here because the v2 division it doesn't come out at the end it actually gives off about halfway through this point so along the way this v2 division the maxillary division is going to come out of this cavernous sinus and move out through a hole in the skull called the foramen rotundum and we'll talk about his branches afterwards but then there's v1 so this is our v2 division so we keep track of it this is our v1 division or ophthalmic division this bad boy is going to move through a hole in the skull called the superior orbital fissure once it gets to this point it branches out to three different branches that we're going to talk about okay so that's just getting ready to go through the superior orbital fissure it gives off three branches so really if we want to we could say here that this ophthalmic division is really giving off three branches moving into this area here okay and we're going to talk about each one of those divisions that being the needs of ciliary the lacrimal and the frontal but to see it an even better way we're going to look at it here first but we're going to see it in another view up there in the top right corner in a second so here we go ophthalmic division goes through the superior orbital fissure when it goes through the superior little fissure like we said it gives off three branches okay three branches one of the branches is actually called the lacrimal blent branch so it's called the lacrimal branch so the first branch we're going to have is called the lacrimal branch the next one it's a pretty interesting one the next one is called the frontal branch the frontal branch and then this last one over here at the bottom is going to be the Mae ciliary branch who okay so now where did these bad boys go okay well the lacrimal nerve is going to move throughout the orbital cavity and here's what we got to remember um let me actually before I go and show you exactly where it is this is not doing it justice to see the exact orientation of how it's coming in so before we keep going let's actually come over here to this top right corner so we can see exactly where it's moving out so I put here we're actually gonna have two parts here we're going to have a nasal side here okay I'm sorry actually this is going to be over here this will be the temporal side here this is going to be on the temple side of the eye okay and this will be on the nasal side of the eye okay so this will be on the temple side of the eye this will be on the nasal side of the eye here's this hole here this hole here is called the optic canal okay this big ol hole here is called the superior orbital fissure and again just in case you guys might be few confused we're taking and looking at the eye imagine here's my eye I'm looking into the back of the orbital cavity so I'm looking in the posterior wall of the orbital cavity and again this is the actual temple side of the orbital cavity this is the nasal side of the overal cavity and this is the posterior wall to upper cavity okay now another structure that's really important is this blue ring or annulus this is a nice connective tissue structure called the annulus of Zen or the common tendon it's ring why is it important because it's the origin for for extra ocular muscles which one's inferior rectus lateral rectus medial rectus and superior rectus right also another function of it is that it separates the superior orbital fissure into two compartments the compartment which is inside of the common tendon it's ring and the compartments which is outside of the common tendinous right why am I telling you this because the oculomotor nerve if you remember as a superior branch and inferior branch and they also remember that the six cranial nerve was running in this area but the actual ophthalmic division that gives off those three branches the nasal ciliary nerve runs right in between the superior and inferior branch and then the lacrimal nerve runs here all the way on the temple side of the supraorbital fissure outside of the comet on this ring the frontal nerve runs just a little bit more medial to that and then the trochlear nerve runs just a little bit more medial to that so really where is the lack of when they're coming it's coming out from the temple side and it's going to supply a gland that's over here which is called the lacrimal gland alright just so that we're clear on that so when we see the lack of motor if it's actually coming on the temple side so in other words if you're looking at me you're looking at my eye it's coming out on this edge of the eye okay the lateral side of the eye alright so we now that we covered that let's see what it's going to do here it's going to come out here and it's going to do two things it's actually going to pierce through the lacrimal gland it's going to pierce through the lacrimal gland and when it pierces through the lacrimal gland it's going to give off a branch here to the eyelid you see right here this is the superior palpebral or the superior eyelid this is the inferior palaver or the inferior eyelid this guy gives off a branch to supply the skin of the superior power Barbra but you know what else is important there's actually a conjunctival lining in others what's called a palpable conjunctiva right here it supplies that conjunctival also so the lacrimal nerve supplies two things it supplies the skin so if we imagine coming out over here it's supplying the skin of the palpebral and it's supplying the underlying conjunctiva but what part what part imagine over here is temple side of the eye imagine over here is the medial or nasal side of the eye okay imagine that this over here this is where the lack of owner would be coming so be coming to supply this part of the palpebral and the underlying conjunctiva okay that's where it would be so beyond the temple side sweet deal recover that now let's do the frontal nerve the frontal nerve acts comes over here and there's actually going to be two branches of it okay two branches of it you notice that's actually called the trochlear right here there's a little bony structure here the called the trochlear and that's where the superior oblique muscle actually moves through so here we have the superior oblique and actually move through here to kind of connect onto the actual top part of the eyeball well this nerve runs right above that right above the trochlear right above it so it's called the Supra trochlear nerve okay so this one here is called the super trochlear nerve and the super chalkeley nerve does the same thing it supplies the conjunctiva of the upper palpebral it supplies the skin of the Palpa bruh and it even supplies the skin of the forehead and a little bit of the scalp okay so this is what nerve right here that's actually moving up here that's actually kind of do it like this let's put a little thing here I'm going to put sp supra trochlear nerve so super trochlear nerve there okay it's going to move above the trochlear give branches to the underlying path or up the conjunctiva the skin of the Palpa in the skin of the actual forehead the other branch is actually called the supra orbital branch i wanted to note that it's s o the super orbital branch is going to come it's also going to give supply to the underlying palpebral the actual palpable conjunctiva and the skin of the palpebral it'll supply the skin of the forehead and it'll go all the way back how far back will it go the supraorbital nerve will actually supply the palpebral the underline conjunctiva the skin of the forehead this sucker will go all the way back until you get to that the vertex ok the vertex so where the actual lambdoid suture is it goes all the way back there whereas the super trochlear nerve only comes to about to around the hairline maybe a little bit above that okay and just to reiterate that we could actually kind of say it like this which one will be right here we could have soup trochlear nerve that will come up here and they would get branches to the path around the underlined conjunctiva and if you want we'd also have right here supra orbital and this would give conjunctival branches palpable branches and it would even go up and supply the actual forehead and all the way back to the vertex of the skull so we deal so we cover those bad boys now we got to go to the monster unfortunately the needs of ciliary so the needless ciliary has a couple branches okay so one of the branches here for the nasal ciliary is kind of interesting it actually gives off a branch or so let's say here's the nasal ciliary it actually can give off two branches here one is going to move with three nerves I'm going to do them a different color so let's say this green nerve is parasympathetic so I'm going to put P s and s nerves then I'm going to do here in red these are going to be identifying sympathetic nerves so s NS these guys are going to run together okay and then running together they pierce the actual sclera so they actually Pierce the sclera and they run through the sclera and what happens is when they have run through the sclera this actual fiber of the nasal ciliary fiber comes up and gives supply to the cornea so it gives specifically Kuch pain temperature fibers to the cornea the actual parasympathetic fibers it'll come through there and it will give off branches to the silly Aris into the iris whereas the sympathetic fibers will do the same thing they'll come here and supply the ciliary and they'll supply the iris what is this whole bundle here called these are basically called your short ciliary nerves the only reason I mentioned is because there's another one called the long ciliary nerves and the long ciliary nerves is just basically a sympathetic branch so I put s and s and the names of ciliary nerve also piercing together okay the long ciliary nerve is just basically going to pretty much be the sympathetic fibers and the nasal silly branch which will pierce the actual sclera and again go and supply the cornea whereas the sympathetic fibers will go and supply the ciliary muscle and the iris so what are these ones here called I'm just going to abbreviate them long ciliary nerves and same thing over here just we can save and conserve space short ciliary nerves okay sweet that's that part now we get into another one for the sake of not making it too intense I'm going to do this one in a different color so that we can definitely follow let me do it in this uh and this teal color here okay this is still going to be a part of the nasal ciliary nerve but I don't want us to get confused here with all of these other purple fibers moving so now what happens is the nasal ciliary nerd is going to give off another branch here but again remember this is still a branch of the nasal ciliary nerve and what it does is it moves upwards okay towards the ethmoid bone as it moves upwards it gives off two branches okay one branch is a little bit more posterior the other branch is a little bit more anterior towards the ethmoid bone we think they're called this one here is the posterior ethmoidal nerve this one there is the and here at the mitral nerve that's it okay and they basically what's their purpose they're going to supply the sinuses so they're going to apply supply the ethmoid sinus the anterior ethmoid own herb we'll talk about here in a second it actually has another branch three more branches but again what's this one here this is the posterior ethmoidal nerve this one here is the anterior ethmoid 'el nerve okay so just so we're clear there the nasal ciliary also gives off another branch which is the posterior lobe which supplies the posterior ethmoidal anise you guys all have an anterior ethmoid nerve which supplies the anterior part of the ethmoid sinus and again if you want to know what this big old shark fin like structure areas it's just one of the landmarks of the ethmoid bone it's called the crista galli and then this whole plate here which is having these holes that plate is called the cribriform plate okay it's called the cribriform plate and the holes are the olfactory Fram and that's where the olfactory nerves run up through okay just so that you're aware okay so now let's look at the actual branches from that anti-earth moodle nerve okay because I want to I want to show you guys something here so what happens is let's say for a second I actually put a small diagram right over here a small diagram right over here real quick okay so let's say here I'm going to have V let's say this is a part of the ethmoid bone with the olfactory foramina on that cribriform plate and if you remember what was this structure right here called this was called the crista galli right underneath it is the nasal cavity literally right underneath this is the nasal cavity okay so if you imagine here this is going backwards like that again this is all a part of the nasal cavity this is the nasal septum right here and if you remember we talked about this a couple times the actual perpendicular plate of the ethmoid bone is one component of the nasal septum the other component is the boma why I'm telling you this is those anterior ethmoid owners remember that was actually coming over here needs a ciliary gives off this branch which is anterior ethmoid 'el posterior ethmoidal the anterior ethmoid will actually continue downwards and go into the nasal cavity when it goes into the nasal cavity gives off three branches okay one is supplying the medial side of the nose so it's called the medial nasal branch I'm just going to put em in be medial nasal branch the other one is supplying the lateral side of the nasal cavity lateral nasal branch but this one is probably of the most interesting this one is actually going to continue and it's going to pierce through a part of the nose and supply the tip of the nose it's going to supply the tip of the nose you know where there's the cartilage of the nose and the bone of the nose there actually is a kind of separation point it pierces right through that separation point between the bone and the cartilage and this applies mainly the tip of the nose okay so this one right there is called the external nasal nerve okay just so we're clear this right here is the anterior ethmoid owner this one right there this is the posterior ethmoidal nerve the antipodal nerve will give branches to supply the ethmoid sinus it will give off a medial nasal branch which is for touch paying temperature of that area lateral nasal banters for touch brain temperature there and an external nasal branch which will be for the touch main temperature for the tip of the nose all right sweet goodness we got that one okay that's kind of a tough one there now let's do another one one more branch of this guy and the ophthalmic division is complete okay so if we go hearing next we're going to have another branch of the nasal ciliary nerve what's going to happen is this branch okay it's not going through the eye so don't get that confused I'm just doing it for the sake of the diagram it's not going through the eye it's actually moving underneath the trochlear remember this one was moving above the trochlear so it's called the super trochlear nerve this bad boy right here is going underneath the trochlea so this one is called the what infra trochlear nerve infra trochlear nerve why am I telling you this one because the in photo clear nerve is also really really important it's going to give a couple different branches okay remember how this was the soup here popover was supplied by the trooper trochlear the supraorbital and even the lacrimal the infra trochlear nerve is very nice and he gives a couple different branches okay best seen in this view here best seen in this view remember there is actually called a certain part of the eye over here you have a certain structure called the lacrimal Karanka okay can uh nice little fleshy part there then if you guys have seen our videos we talked about the eye we know that we have these little canals over here called the lacrimal punctum and then you have black rimmel canal lick you lie which goes into the lacrimal sac right well what happens is some of them the infertile clear nerve is going to give two different things it's going to supply the palpebral the superior palate abroad okay more medial it's also going to supply the lacrima korone cool so it's going to supply that lacrimal chronical and it's going to give supply over here to the lacrimal sac okay so what three structures is it going to supply the in for Oakley own herb is going to supply the palpebral the most medial part of the Palpa bra and the underlying conjunctiva it's going to give supply to the lacrimal sac and it's going to give supply to the lacrimal core uncle that little fleshy Biddy part in the middle of your eye okay all right sweet deal so we covered that one so the in photo clear nerves will give off branches to supply the palpebral underline conjunctiva it'll also give off a branch for the lacrimal sac and or give off a branch for thee what else the lacrimal chronicles' lacrimal sac and her uncle the lacrimal chronicle and again these are basically your touch pane temperature and pressure fibers holy sweet goodness we have done the ophthalmic division okay unfortunately that's not the worst of it all right so so far we've covered the ophthalmic division sweet deal now let's go ahead and move on to the actual maxillary division the maxillary division is a little bit tough I'm not going to lie so we're going to try to go through this piece by piece the best we can all right so we said that the v1 went through the superior orbital fissure right the v2 moves to this nice little hole in the skull and this hole right here is called the foramen rotundum this is where the actual maxillary division runs through as the maxillary division is running through it gives off of a current branch here it gives off a nice little recurrent branch and this recurrent branch is going to supply what is this here your meninges it's going to supply the dura mater because the dura mater is pain sensitive so one branch here is going to be what's called the an NGO branch so you're going to give off what's called a meningioma branch okay so man injeel' branch or a dural branch we can even say Durrell branch specifically it's supplying the dura mater not the arachnoid mater and the PIA mater okay all right sweet then as it comes out of the foramen rotundum it moves into a special structure that is kind of interesting it's actually called the this little fossa here it's kind of a little bit posterior to the orbital cavity and a little bit more inferior to it this cavity right here or fossa is called the tear go it's actually right above it tear go palatine fossa and this is probably a really really interesting one and the reason why is because it has some gang Leon in here so it actually does have some gangly on here so what is a gangland against a group of cell bodies located within the peripheral nervous system now what happens is this actual maxillary division is going to move through the terrible Palatine fossa but it does give off some branches here to the tear go Palatine ganglion so what does that green group of cell bodies they're located within that area this right here is called the tear go Palatine ganglion so I'm going to put tear go Palatine gangly on little ladies you don't want to write all that in there tear go Palatine ganglia and good for cell bodies are located within the penis so it does give off some branches there but then what happens is from here it gives off three branches bop-bop-bop okay so three branches here one branch is called the posterior superior alveolar nerve so one of the branches here and I'm going to put posterior superior alveolar nerve okay the other one is called the infra orbital nerve and the last one here is called the zygomatic nerve now what happens is the zygomatic nerve in the infraorbital nerve run up into the orbital cavity through with this little hole in the bottom part now this was called the superior orbital fissure this is the inferior orbital fissure so the zygomatic nerve okay so now that we know what they are and I've written them down let's abbreviate them for space sake all right so zygomatic nerve here and infraorbital nerve these two are going to move through the inferior orbital fissure okay what does that hold they're called inferior orbital fissure okay cool now the zygomatic nerve as it runs through here it gives off two branches okay we're not going to be able to see them very very well here I'll show you in another diagram in just a second here but it's going to get off one branch I'm going to denote it as ZT because we're going to talk about it called the zygomatic oh temporal branch and another one called the Z F which is the zygomatic aphasia branch the other one is going to give this guy here this infraorbital nerve and what happens is the infraorbital nerve is going to run on the the floor of the orbital cavity they call like the infraorbital like groove but then what happens is it moves through a hole right here there's a tiny little hole underneath the orbit about right here okay it's called the infraorbital foramen so let's kind of make this nice little hole here here's our infraorbital foramen this guy goes through this hole here called the infraorbital foramen and gives off three branches one branch is going to go here and supply the inferior palpebral right and the underline conjunctiva I just get so excited about this I'm sorry another branch is going to continue downwards and supply the upper lips let's apply the upper lip and the other branch is going to go and supply the actual nose so it gives us three branches one is an inferior pop of a wrench the other one is a nasal branch and the third one is going to be the you know you can call a lips you can also call them labia all right doesn't mean to have a vagina on your face it just means it's lips lips is labia so you have the superior labial branches okay all right all right so we got that that's the end for battle nerve now I said I was going to talk to you about the zygomatic or temporal zygomatic facial I was gonna show you in a different way because this does not do it justice here so let me do that real quick on this bottom guy here with the Mississippi mud flap okay what happens is you're going to have two branches here let's say it's coming from the orbital cavity right here one branch is going up and it's supplying the temple that's it it's supplying the temple that's the zygomatic Allah temporal branch the other branch is coming over here in supply mainly the cheek area okay so the zygomatic bone a little of the cheek area that's the zygomatic 'el facial branch that's it done its supplying touch pain temperature pressure fibers to thee if it's here is IO medical facial if it is here is I go medical attempt or done that's it okay like I said seeing it like this does not do it justice so we showed you like that right there okay fortunately still not done okay now from the infraorbital nerve okay so let's put it here again so we don't confuse that this one is right here just kind of putting it in between as an intermediate IO infraorbital nerve okay it gives off two more branches I did not show you what the posterior superior alveolar nerve is doing now this is probably something I should show you it comes over here and it gives supply to the hard palate a little bit of the teeth but what teeth is a really really supplying the molars so this guy right here supplying the molar so it's applying the actual molars and you know there's that the skin coming right up over the teeth of gingiva it's supplying that too so it's giving even a little bit of supply to the actual tissue over that area which is called the gingiva supplying the molars and the gingiva okay that's the posterior superior alveolar nerve and just to be saved space as much as we possibly can here let's put this as PSA okay not prostate specific antigen okay this is going to be posterior superior alveolar nerve all right so posterior superior alveolar nerve now the reason I'm putting it like this is because there's off the infraorbital nerve is two branches so off of this bad boy here you're going to give two branches this one here and this one here so there's this one coming right in the middle so this is posterior this would be anterior and this is middle so I'm going to put here that we know it's the middle superior alveolar nerve this one is going to be the anterior superior alveolar nerve the middle superior alveolar nerve is supplying the premolars and again the actual gingiva around it okay so even the gingiva the anterior superior alveolar nerve is going to supply the canines right the canines and even the incisors the central incisors and the lateral incisors and just in case for those of you who are like you can also call you know you have those called the cuspids and the bicuspids if you want to call them that too for you can actually call again you have central lateral incisors you have the canines and you have the cusp it's in the bicuspids too but again I'm just going to say here cane I'm going to keep it simple canines and sizers premolars and molars and the end you have three molars two premolars and then you have the actual two canines here and then the actual two centralizers and two lateral incisors okay so that's going to be supplied by these guys all right so that's the big part of the the maxillary branches there's a couple other parts that we have to cover though and it's coming from this ganglion area okay so from this ganglion there's going to be a couple different branches that are coming out here okay so coming through that tear go Palatine ganglia there's going to be a couple different branches that we have to talk about all right here we go one branch is actually going to come down here and give supply to the nasal pharynx so one branch is going to come down here and it's going to supply the nasal pharynx nazo for injeel' branch another interesting point here is if you guys remember the eustachian tube or the French or tympanic - but the auditory tube you know that there's actually the little accent of that fringe of tympanic tube right here right and then right around it you know you have like the tonsils the tubal tonsils there's a little tubal tonsils that are actually lymphatic tissue wrapping right around this area this guy here this actual nasopharyngeal branch is going to give some fibers that will come over here and supply the fringe of tympanic tube maybe a little bit of the skin over the tube will tonsils okay so the nasal pharyngeal branch is going to supply the nasal pharynx it's going to give some branches to the frigid tympanic tube and maybe a little bit of the skin of the tubule tonsils there all right that's that bad boy all right let's see if we can do this one here let's do another one here this branch here this branch here is going to come into the orbital cavity okay and it's going to give a touch pain temperature supply to the actual orbit so it's going to give touch pain temperature to the actual orbital cavity so touch pain temperature fibers to the orbital cavity so what would you call this branch and so we notice they call the terrible Palatine fossa I'm going to get this out of the way this is actually called the orbital branch so this one right here is called the orbital branch okay then we have another one here okay let's see if we can get this bad boy here another one here is going to come from the back here it's going to come out the back here and it's going to move let's see if we can follow this one down here this guy's going to come and it's going to supply the soft palate and a little bit of the actual uvula okay so this guy here is going to come and supply the actual soft palate this one here is called the lesser Palatine nerve okay so this one here is called the lesser Palatine nerve holy crap we're doing all right here okay so we got a nasopharyngeal branch we got a lesser Palatine herb which is supplying the soft palate and then we also have the orbital branch which is applying the actual orbital cavity okay we have another one here it's going to move with that lesser Palatine nerve in a similar way okay let's see if we can get this bad boy in here now okay here we go this next one here so we're going to bring him downwards and this one's going to move next to the actual lesser palantine and when it does it's going to go and it's going to only supply the actual hard palate okay so it's going to supply the posterior part of the hard palate so again what is this nerve here called this one is called the greater Palatine nerve okay so let's recap here how many branches do we have coming off of this gangly honor these ganglionic branches we have an orbital branch which is one supplying the orbital cavity we have the nasopharyngeal branch which is applying the nasal pharynx the fringe and tympanic tube and liver the tubule tonsils we have the lesser Palantine nerve which is going to be supplying the soft palate we have the greater Palatine area which is supplying the posterior part of the hard palate there's another one but this one's really hard to see from this angle and plus with all this gibberish we got going on here so what we're going to do is we're going to come over here for a second to a mini diagram okay so a mini diagram over here again what would this here call this is called at ergo Palatine fossa with the Terrigal Palantine ganglion and again what nerve was running through here this is your maxillary division and it gave off those ganglionic branches right remember some of the branches will actually move through when they move through the empty into the post here part of the nasal cavity so they come into the posterior part of the nasal cavity so since they come into the posterior and even a little bit upper so I could actually kind of show like this so posterior in itself actually in the upper parts of the nasal cavity so this is called the posterior superior nasal branch so the posterior superior nasal branch what happens is it actually gives off two branches here one like this and one like this one is going to supply the medial wall so this would be called the medial nasal branch another one's going to supply the latter wall so this would be a lateral nasal branch and then it'll have another one another guy which is actually going to go through a hole in the actual hard palate there's a nice little hole within the hard palate here what is that hole here called this hole is actually called the incisive philosopher Raymond and the text that I read was done incisive fossa and it comes out and supplies the hard palate but specifically the anterior hard palate the greater Palantine supplied the posterior hard palate so again how many branches off of this sucker here so again this branch was d well how many branches is that that was three four so we had how many again we had orbital branch we had the nasal pharyngeal branch we had the lesser Palantine greater Palatine this is the fifth one okay so the fifth one is going to be the posterior superior nasal branch which gives off a medial nasal branch which supplies the medial walls of the nasal cavity the lateral nasal branch which supplies the latter walls of the nasal cavity and this other one that moves through the incisive flossing into the actual oral cavity to supply the hard palate what is this bad boy here this one right here is called the nazo Palatine nerve okay and if you guys are interested I know you guys are the hole that this guys go into to get into the actual nasal cavity area it's called the sphenoid palatine frame and actually go through is called the sphenoid Palatine foramen okay all right that covers that holy crap guys we did the maxillary division let's keep going we're almost done we're at the home stretch here let me get this out of the way so that now we can do the mandibular division and this one's not that bad of all of them it's probably one of the easier ones and we're going to introduce a new concept here okay so we've got V 3 V 3 moves through a nice little structure here and it actually moves through a hole in the skull here called the foramen ovale other structures that move through this area also but we're not going to spend any time talking about that ok here's what we're going to talk about now and I want to do this one we're going to do in black we'll do it in black from this guy here so let's actually make this nucleus black here this nucleus here is the motor nucleus of the trigeminal nerve so this is actually going to be the cranial nerve 5 motor nucleus and so what happens is it gives off motor fibers and these motor fibers this black is good it actually is going to move through the foramen ovale it moves through the foramen ovale with this actual sensory division you know what she wanted me that I didn't tell you what kind of fibers these guys work you see these actual purple fibers I told you that there touch paying temperature proprioception all that stuff like that but they're even more specific these type of fibers are actually called g SI fibers which means that they're consistent they've called their general somatic a Ference which a touch pain temperature proprioception pressure fibers right these black fibers here are called s v e phi burs and the reason why is they're called special visceral efferent is because these guys supply what's called the first pharyngeal arch there's actually during embryonic development you have these things called Ferengi arches there's the first second third fourth and sixth and what happens is the actual special events or efferent fibers from the trigeminal motor nucleus supplies the first four in charge which is the muscles of mastication the tensor villi palate tonight and the 10th sorted panel and we'll talk about that ok so cool we got that so now what happens is it moves through the foramen ovale what then we have to give off a branch here so there's actually a artery that comes here up through this area here it's actually a branch off of the external carotid artery very very important artery especially when it comes to what's called epidural hematomas that can develop this right here is called the middle meningeal artery it actually runs up through that area and actually goes into this nice space here which is called a nice little epidural space that's why if you ever get hit real actually run right through the temple very very yes is the most common part for the epidural hematoma if you get hit really really hard there you can actually rip through the middle meningeal artery and cause blood to accumulate and lead to a hematoma that can compress the brain and cause and increased intracranial pressure but anyway we're not talking about that I'm just keep saying here then it runs up through this area what happens is it gives off fibers that move with it through the dura mater ok gives all fibers that move with it within that dura mater this branch here is called the nervous spino system ok that's called the nervous actually I think there's a you yes my gnosis so it's called the nervous by gnosis that's one branch as it moves through it gives off another branch because it's going to come down here it's going to give off this branch that moves with the minimun middle meningeal artery called the nervous by gnosis it's also going to give off another branch back here gives off another branch here that's going to move all the way out here and come and supply this is a heck of a journey the ear ok so it's going to supply the external ear ok so it's going to supply the external ear and this is called the auricular temporal nerve so you can already also get from this that it's not just supplying the actual external ear if you imagine that this is a part of the temple it would give off branches to the temple region also okay so the Fache are there where the temple is ok auricular temporal lobe that's another branch and again these are still gsa fibers but as it moves downwards let's follow these motor fibers now these motor fibers they come through this area and they give off a boatload of branches here I mean I shouldn't say Bowl oh they give off three branches ok one branch is going to go and supply a lot of these muscles of mastication another branch is going to go to the tongue and another branch we'll talk about in a second it will actually go and supply some of the actual teeth okay so let's go through each branch here let's do let's actually follow this bad boy we'll do that one later let's just follow this one right now we're going to say that this one is the branch to the muscles of mastication since they're right here this is a way better view here okay so there's a couple muscles of mastication here let's actually highlight them this one right here is supposed to be the masseter this one right here is going to be the temporalis this one here is going to represent thee and again these are not anatomically perfect I'm doing it so we can get the point here this is going to supply the lateral pterygoid and this one right here is going to be the medial pterygoid this bad boy here this branch which is actually a part of the anterior division of this motor fibers right it's going to give off a nerve that supplies the actual temporalis this nerve is called V I'm going to abbreviate it deep temporal nerve so it's going to give off a branch called a deep temporal nerve it's going to give off another branch which is going to come over here to the masseter what I think this one's called this is called the masseteric nerve Massa Carrick nerve it's going to keep going down here and it's going to also give off a fiber here that it's actually on its own it's not a part of the anterior vision so let me actually kind of put like a little asterisks apart on this one this is not a part of the anterior division this masseteric nerve is the part of the anterior division this one is actually just an individual branch here to the medial pterygoid and then it's going to give off another branch which is a part of the anterior division which is going to go to supply the actual lateral pterygoid okay this is actually called the nerve to lateral pterygoid I want to put NLP nerve to lateral pterygoid what also happens is it gives off one more branch here but really we should actually be specific because this branch it actually it's a weird one it's a really weird one here okay it gives off another branch to the ladder of pterygoid but the fibers that are moving with it it actually has some sensory fibers here that are moving with it here and these sensory fibers are going to go and supply the cheek okay so really as it's moving here if I follow these actual purple violet fibers up back all the way here some of these actual general somatic efferent fibers are actually moving and gives off a branch here to the lateral pterygoid and gives off a branch of supply the skin of the cheek this branch here is called the buccal nerve okay it does not supply the Vox inator that's the actual function of the facial nerve okay so again which ones are being supplied temporalis by these deep temporal nerve medial pterygoid which is not a part of the anterior division masseteric nerve which is actually a part of the anterior division lateral pterygoid through the nerve to the lateral pterygoid and then there's going to be another branch off the buccal nerve which is going to supply the lateral pterygoid and then the bucco nerve is also gonna have a sensory branch which supplies the skin of the cheek holy crap we did that okay now let's keep her going here let's keep her going and let me actually kind of make sure that all of these branches here are separate here from this three branches believe me three branches here so really this is the one branch here so we should have it all like this that's better like I just got to be picky okay because again this was one branch that was actually going to supply all of these muscles of mastication there's another branch which is going to be for the lingual nerve and another branch which is going to supply specifically the teeth and even the skin of the chin okay we'll talk about that holy crap let's follow this one here this one here is going to continue and it's going to move through a hole within the mandible there's a nice little hole here within the mandible that it's going to move through what did that hole there called it's called the mandibular foramen so moves through a hole called the mandibular foramen and as it's moving this way it actually is going to give off branches that come over here to supply the teeth so it's going to get branches that come over here to supply the teeth what does this branch here called this branches that are actually coming off of that is called the inferior dental nerves so they're called the inferior dental nurse as we continue from that point there's going to be fibers that are going to come out through another hole within the mandible what does that hold they're called that hole is called the mental foramen so it's called the mental foramen out of that you're going to have the mental nerves coming through here the mental nerve is going to supply the skin of the chin so it's going to supply the skin of the actual chin or why as we call it the mental region okay so again this nerve here is going to move through the mandibular foramen it's going to give off inferior dental nerves and then it's going to continue out through the actual mental foramen and give off these mental nerves which are going to supply the skin of the actual chin now it also gives off another branch that comes over here and supplies to other muscles to other muscles here one less we're going to draw like this and we're going to say that there's another one moving like this and these are both connecting to a bone right here I want to put the bone right here this bone is the only bone in the body that doesn't articulate with any other bone in the body okay so this is actually going to be a bone that articulates with no other bone in the entire body this is called the hyoid bone this is going to give off branches to to muscles one is going to be going to the stylohyoid so this muscle right here is called the stylohyoid the other one I'm sorry not the stylohyoid this is actually called the mylohyoid I'm sorry about that it gives off one branch which goes to a muscle called the mylohyoid it gives off another branch which is going to the digastric and tear your belly okay this nerve here which is coming off is actually called the mylohyoid nerve so this one's called the mylohyoid nerve this one right there this nerve though which was actually moving all this way this bad boy right there this is called the inferior alveolar nerve okay so just to recap that we have the inferior alveolar nerve it's going to move through the mandibular foramen it gives off a branch called the mylohyoid nerve which supplies the mylohyoid and the digastric and tear belly which are super high weight muscles so they elevate the high bone it's going to give off another branch which is the inferior dental nerves which are going to supply the teeth and it's going to give off another brand which is going to be through the mental nourish apply to the skin of the chin now really moving through here if we were to really be specific the purple fibers are the ones that are the gsa fibers right so really if we really wanted to be particularly all of these fibers here that are actually coming off to the teeth are really the gsa fibers and then the actual fibers are coming out to supply the skin of the chin are also gsa fibers the only motor fiber is the one that's going to the mylohyoid nerve okay just so we're clear on that okay so again this would all be GSA's fibers and the black ones are going to be the SVG fibers holy crap we're almost done guys I promise we have another one this one right here is going to be a really cool one this is called the lingual nerve the lingual nerve will move down okay it will continue downwards and as it's moving downwards it's actually going to go and supply the anterior 2/3 of the tongue so this is going to be the lingual nerve and the lingual nerve specifically is going to be taking GSA fibers so if we're being really really particularly here this black nerve really should be purple if we really want to be particularly because we've been keeping the GSA fibers here purple so we should actually make this purple here too so really the lingual nerve is actually GSA fibers and these GSA fibers here are actually going to give what touch pain temperature fibers to what the anterior two-thirds of the top okay so it's going to be giving touch pain temperature fibers to the anterior two-thirds of the top so again that's the lingual nerve now why am i mentioning this because there's something else that moves with it okay so another nerve that's really worth mentioning is going to be the seventh cranial nerve okay I'm not mentioning these things just round sake I'm doing it because I really I really want this to make sense guys so the seventh cranial nerve is going to move through this bony canal within the middle ear and this bony canal within the middle ear is called the facial canal we actually have a video on the middle ear anatomy with the external ear okay now what's important is as this seventh cranial nerve is running through here let's say that this is actually going to be able to put m4 motor fibers there's going to be other ones that are moving with it what else would be nice and bright let's use this link steel color here to go with it let's say over here we're going to have sensory fibers so this is going to be sensory fibers these are going to also be moving with the motor fibers of the seventh cranial nerve okay okay there's another one here which we're going to make here and Brown and these are going to be the parasympathetic fibers so we have three fibers so far moving through this area motor fibers we're going to have parasympathetic fibers in these actual sensory fibers what happens is the parasympathetic fibers and the sensory fibers come out of the bony canal so they come out of the bony canal so let's actually say here's the parasympathetic fibers they come out of the bony canal and they go through a hole within the posterior wall of the middle ear so this is the middle ear here again it comes through this hole within the poster wall called the posterior canal Achilles so that little hole in the back is called the posterior canal Achilles and these fibers move anteriorly and come out the anterior canaliculus of the middle ear why am I telling you this because with it these Tila fibers are moving so look at this these tail fibers also decide to peel off and come out with this area - with these actual parasympathetic fibers this whole thing here that's moving like a cord within the middle ear is called the chorda tympani so again what is this structure right here called this whole structure here is called the chorda tympani these fibers are going to move with the actual lingual nerve so now we got to bring this bad boy up through this way so I'm going to bring this fiber up here and I'm going to bring the teal fibers up there and again the do to brown fibers are going to be what the blue brown fibers are representing the parasympathetic fibers the teal fibers are representing the sensory fibers these all run with the lingual nerve so they hop on with the lingual nerve and move with the lingual nerve okay so it's actually follow these teal fibers all the way down here okay these teal fibers are sensory fibers when they move with the lingual nerve they come all the way out here to the tongue to the anterior tooth is along where the lingual nerve is and what they're specifically doing is these teal fibers that are part of the facial nerve they're picking up taste they're picking up taste but again that's for the facial nerve I just want you to realize that with the lingual nerve these SVA fibers which are taste fibers these teal fibers are moving with it the other fibers that are moving with it are these doodoo brown fibers and they'll continue and eventually come out in synapse and a ganglion called the submandibular gland Leon and they'll go out to glands okay just in this case it's going to be called submandibular salivary and submandibular link I'm sorry submandibular lingual submandibular salivary glands and sublingual salivary glands and this is going to cause the production of saliva okay so just so we're clear here the lingual nerve is picking off two fibers from the facial nerve this is the lingual nerve here and within the lingual nerve it's carrying with it two fibers from the quarters and pana that hop on the fibers here the brown ones are the parasympathetic nervous system fibers they're the cause the salivation the teal fibers are going to be the SVA fibers and these are taste fibers but remember this is not a part of the fifth crane on earth this is for cranial nerve seven but they're moving on the link with the lingual nerve which is a part of cranial nerve five okay just so that we are completely clear one more and we're done one more guys more muscle as it's coming through this area it gives off another little individual branch here it gives off another little individual branch here which comes to this muscle right here this is called the fringe of tympanic tube there's a muscle that's right superiorly to it it's going to be right above it this muscle here is called D tensor tympani and the tensor can pay and I actually it connects to a bone it's going to be hard to see from this angle because we've pretty much flooded the board with informations like nowhere else to draw but I want you to trust me for right now that this tensor tympani is actually attaching to a bone a little obstacle inside of the middle ear cavity called malleus and what it does is it pulls malleus medially which tenses up the tympanic membrane because nataly's is connected to the tympanic membrane when it tenses the DIMM panic membrane it makes the tympanic membrane very very tense and very less sensitive to compression and decompression what's the purpose of that to make the actual sound waves less less intrusive what do I mean whenever you're chewing food this this nerve is called helping the actual mastication process you know how loud it would be if we didn't have this tensor tympani function while we're chewing it would be so loud we would hear herself so loudly chewing so thank goodness for this trigeminal nerve innervating the tensor tympani pulling on the malleus medially to tense the tympanic membrane to dampen some of the sounds whenever we're chewing alright so last thing i want to talk about to finish everything off and i thank you guys for sticking in there with me throughout this whole process is absolutely amazing if you guys have stuck in there the actual last thing I wanna talk about is called trigeminal neuralgia which was that last clinical correlation that I wanted to discuss so trigeminal neuralgia and this is not gonna we're not going to have a whole long discussion I'm just basically going to give you the synopsis version of it okay there's specific arteries okay one is called the superior cerebellar artery if you guys remember we've talked about this so many times there is a vessel moving right here called the superior Oh artery and if you guys remember there was also another one called the posterior cerebral artery we talked about this an oculomotor nerve a trochlear nerve this SCA the superior cerebellar artery is the most common okay there's two causes of trigeminal neuralgia generally one is idiopathic okay so what is idiopathic meaning it could be anything you're not really completely sure but that only accounts for 10% of that called the causes so 10% of it is kind of like idiopathic the other 90% of trigeminal neuralgia is due to the superior cerebellar artery actually compressing the nerve root so imagine here that this superior cerebellar artery is actually compressing the nerve root okay for whatever reason the loop of that superior cerebral artery is compressing the actual nerve root now which areas of the trigeminal nerve are most commonly affected any branch could be affected but the two most common branches that are affected are trigeminal neuralgia is v2 and v3 okay so in trigeminal neuralgia 90% of the cases is due to superior cerebellar artery compression of the nerve root 10% is idiopathic most common areas affected is the actual maxillary division and the mandibular division okay that's that how would these patients be presenting they would be presenting with excruciating lancinating stabbing cutting pain that radiates from the jaw up to the ear up to the actual nasal cavity even up to the eye and it can last for seconds even up to about a minute or two minutes it is extremely painful and it can actually happen up to a hundred times a day okay so this can happen almost a hundred times a day could you imagine that amount of pain they say it's one of the most excruciating pains a person can go through okay so how they treat this is a couple different ways generally we're not going to go through every single part of it I'm just going to say that there's a couple ways to treat it um one is you can do it with medicine okay you can medically manage it by giving them what's called car bama the pain which is a anticonvulsant you can also give them another one called gabapentin they're not really sure of how the mechanisms of these are working but they know that it actually does help to be able to reduce some of the pain in this at of the spasms that are coming from the trigeminal neuralgia or you could do surgical intervention okay and the most common one that they usually do is actually what's called a surgical decompression okay so a microvascular surgical decompression surgery and i actually go in and alleviate that that loop that artery that's actually compressing on the actual nerve root they get rid of it or they could do what's called radiofrequency ablation where they hit it with radio waves to destroy it or they can do it's called Gamma Knife surgery okay where you hit it you hit a specific area of where the actual damage is where the actual all this trigeminal nerve root is being damaged you hit it with small amounts of gamma rays and actually destroy the actual tissue okay but it's very very pinpoint focused so in conclusion trigeminal neuralgia is a very lancinating cutting stabbing pain that's rating from the actual jaw up to the ear up to the actual maxillary region up to the eye nasal cavity and it is extremely painful that can last from seconds to minutes almost a hundred times a day 90% of the cases is due to a superior cerebellar artery compression of the nerve root ten percent could be idiopathic the most common areas affected is v2 and v3 and you treat them usually with carbamazepine or gabapentin which is basically anticonvulsant or you can do a surgical decompression surgery and if necessary you might even have to do some type of radiofrequency ablation initiatives I hope all of this made sense I really hope you guys enjoyed it if you guys stuck in the whole time in this video I can't thank you enough iron engineers as always until next time