all right ninja nerds in this video we are going to talk about medullary lesions we'll talk about medial medullary syndrome lateral medullary syndrome before that though i want to take a teensy bit of time to just kind of quickly very quickly we're going to brush through this quick anatomy of the medulla and we're going to talk a little bit about the blood flow the reason why it's very pertinent for us to understand a little bit about the anatomy and some about the blood flow in order for us to understand these syndromes so let's go ahead and do that first all right nigeria so what we're going to do first okay before we start going over all these syndromes we have to talk a little bit about the anatomy and a little bit about the blood flow so what i want us to understand is a guy if you want more detail on all this stuff go watch our video where we have uh all the in-depth discussion about the anatomy and the function of the medulla but really quickly what i want us to understand is i'm going to draw a small little diagram here okay this is our sagittal section right if you guys remember midbrain pons medulla spinal cord cerebrum cerebellum right we're taking a section of this cross section at more of the top aspect and actually thankfully most of the syndromes medial medullary and lateral medullary syndrome most of them occur at this top part so let's say that we took a section here at one that's the most rostral the most superior the most at the top portion of the medulla if you will and then here at the bottom as we go towards the medulla into the spinal cord that's going to be the most caudal portion the one the reason why i want to mention the difference between these two is that the blood flow is just a teensy bit different to the medulla at the most rostral portion in the caudal portion and i'll discuss that but for right now i just want to quickly brush over the anatomy at this section one okay which is going to be pretty much at that pons medulla junction then what we'll do is we'll briefly go over blood flow and i'll talk about the difference in blood flow at these two portions okay all right so let's go ahead and take a look at this section here quickly quickly quickly we're going to say again ventral medulla dorsal medulla okay we're going to kind of quickly go through these structures because it's pertinent we understand them first thing here in the dorsal aspect what do we have here i'm going to abbreviate them this is our hypoglossal nucleus cranial nerve 12. here in blue we have the dorsal nucleus of vagus next to it as we go laterally we have the nucleus of tractus solitarius as we go more laterally we have the medial vestibular nucleus and we have the inferior vestibular nucleus as we go a little bit more laterally you get these purple guys here what are these guys that's your dorsal cochlear nuclei this one is your ventral cochlear nuclei go a little bit more laterally what is this son of a gun he is the inferior cerebellar peduncles right okay move continuously here what do we got here this is our ventral or anterior spinal cerebellar tract so we'll put ventral spino cerebellar tract okay move a little bit here now we got this bad boy what's this son of a gun right here this is our inferior olivery nucleus so inferior olivary nucleus okay move a little bit here what do we got here this is our corticospinal tracts which is going to be carrying those descending motor fibers what do we got here this is our medial lemoniscus this blue guy here this is our spinal lemoniscus come over here to this green structure this is our spinal nucleus of the trigeminal nerve and this is the spinal tract of the trigeminal nerve as we move here to this green structure this is the inferior salivatory nucleus this blue guy here is our nucleus ambiguous this orange guy here is our descending sympathetic tract so this is the descending here we'll put dst descending sympathetic tract move back medially here the black one here this is the tacto spinal tract and this purple one is the medial longitudinal fasciculus one more time so that we completely understand this hypoglossal nucleus dorsal nucleus of vagus nucleus attractive solitarius medial and inferior vestibular nucleus the dorsal ventral cochlear nucleus inferior cerebellar peduncles ventral spinal cerebellar tract inferior olivery nuclear complex corticospinal tract medial meniscus spinal meniscus inferior salvatory nucleus spinal tract and spinal nucleus the descending sympathetic tract the nucleus ambiguous inferior salvator nucleus tectospinal tract and medial longitudinal fasciculus we understand this now it's going to be easier for us when we cover the lesions okay next thing we're going to talk about is a little bit about this blood flow okay because the blood flow to these different sections of the medulla is critical you guys remember from the circle of willis what do we have these arteries coming up here what are they your vertebral arteries they're coming up through those transverse foramina within the cervical vertebrae right eventually as they come up here what do they do they eventually start coming together getting ready to fuse whenever they kind of fuse together what do they make they make your basilar artery as they move up towards the midbrain they give off the posterior cerebellar cerebral artery so posterior cerebral artery vertebral artery this would be your left this would be your right here we'll put that right vertebral artery left vertebral artery posterior cerebral artery now along the way here's our basal artery we also going to give off some branches off of the vertebral arteries you're going to have some branches you see off this vertebral artery we're going to have a branch coming down here and one coming like this this artery that kind of comes off of the vertebral arteries and works its way down the anterior aspect of the spinal cord is called the anterior spinal artery there is another one and it works in the back okay so it works on the back of the medulla and down the back of the spinal cord and that one is called the posterior spinal artery so again the one in the anterior portion formed at more of the superior aspect or rostral aspect of the medulla is the anterior spinal artery the one that's formed just a little bit more inferiorly and on the posterior aspect of the medulla and down the spinal cord is the posterior spinal artery you also have this branch coming off here what is this guy this is your pica right the pica is your posterior inferior cerebellar artery posterior inferior cerebellar artery what else do you have you also have this one this is your icah icah is going to be the anterior inferior cerebellar artery anterior inferior cerebellar artery and then the last one you have coming off of this portion around the midbrain is your superior cerebellar artery okay so what are the arteries that we want to focus on here the ones that we want to focus on i'm going to kind of highlight here is your vertebral arteries and they're going to be supplying the medulla as you can see here the other one is going to be this anterior spinal artery this is supplying the medulla also and even as you see out here the pica the posterior inferior cerebellar arteries and the last one that i want to mention that you can see at the most caudal portion of the medulla teensy bit of it is the posterior spinal artery so we know that these are the main ones the most medial portion of supply by the uh particularly the anterior spinal arteries a little bit more laterally is the vertebral arteries and then the most laterally and kind of posterior are your picas so let's kind of shade that in here so again if you kind of imagine here i'm going to kind of make this kind of like line here this kind of red line here all of this portion here that i'm kind of highlighting all of this this is all supplied by what vessel the anterior spinal artery so this whole portion here all of it is supplied by the anterior spinal artery as we go a little bit more laterally what is going to be supplying this portion let's do it in a different color we'll do it here in this kind of like greenish color here this guy right here is going to be the vertebral arteries so your vertebral arteries are supplying this portion so you have your vertebral artery supply in this portion and then the most lateral portion of the medulla kind of this portion here is supplied by the posterior inferior cerebellar artery your pica okay so again what i want you to remember is just in the simplicity sake more medial midline is anterior spinal artery kind of a little bit here in the middle is your vertebral arteries and the most laterally is your pica the big ones the two ones that you can't forget you have to remember this is your pica and your anterior spinal the reason why is what is the anterior spinal artery supplying more of the medial aspect of medulla guess what that's going to cause if there's a if there's an inf a kind of an occlusion in that vessel it's going to cause medial medullary syndrome if there's an occlusion in pica which supplies more of the lateral aspect of the medulla what's that going to cause lateral medullary syndrome so it's pretty simple now the last teensy bit of the thing that i want you guys to remember is if i were to just kind of draw a very quick diagram here here i just want you guys to remember here's our midline right if we're at the most caudal portion so this is going to be at the caudal portion here we covered at the rostral portion at the most caudal portion it's going to be pretty much the same blood flow i'm going to put here anterior spinal artery then you're going to have here the vertebral artery then you're going to have here your pica the only thing that's different is that a teensy bit of the posterior aspect of the medulla and the most cuddled portion is supplied by that posterior spinal artery just one thing i wanted to make sure that we're clear about okay but for the most part big ones anterior spinal and pica now that we know our anatomy and our blood flow let's move on to the lesions all right so now that we've kind of covered the neuroanatomy we talked about the blood flow again big one i want you to remember anterior spinal more the outer aspect is going to be the pica okay so this one that we're covering is going to be a lesion involving primarily what vessel because it's going to be a medial type of lesion in the medulla this is medial medullary syndrome let's write that down what is this son of a gun here this guy is our medial medullary syndrome okay so what vessel is causing the infarct here this is going to be an infarct of the uh it's going to be an infarct or occlusion of the anterior spinal artery whether it be an embolus whether it be a thrombus whatever the anterior spinal artery is occluded what three structures is damaged that's what i want you to remember okay three structures that are damaged you guys remember the neuroanatomy here what was that pink structure there the hypoglossal nucleus so the hypoglossal nucleus and the nerve coming out right so the hypoglossal nucleus and if you guys remember the nerve is obviously going to be exiting here it's going to be leaving like this right that's also going to be damaged so the hypoglossal nucleus and the hypoglossal kind of nerve is going to be damaged what else is damaged what is this blue structure here called that's your medial liminiscus and your medial limb meniscus is obviously important because it plays a role within that sensations and we'll talk about what sensations and in the ventral aspect here this is going to be the corticospinal tracts so three structures that are damaged hypoglossal nucleus and nerve medial meniscus corticospinal tracts if those are damaged because of a occlusion of the anterior spinal artery what are the clinical manifestations that these patients will present with okay let's look here at this first diagram all right so we'll talk about the hypoglossal nucleus first so the hypoglossal nerve hypoglossal nerve if this bad boy is affected how will the patient present well you guys got to remember what does the hypoglossal nerve do we talked about it in that medulla video we said that it supplies the tongue muscles right the styloglossus the hi-lo glosses the genioglossus which i said is a really important one that i want you to remember particularly pertinent to this it also supplies like the chondroglossus and your intrinsic muscles of the tongue but the big one that i want you to remember here that we're going to kind of discuss here is that genial glossus muscle so let's write this guy down here so this is our genioglossus do you guys remember what this muscle does the genioglossus of the tongue we said primarily helps with protrusion of the tongue right so for example this is the right the right genioglossus this is the left genioglossus the right genio glosses will protrude the tongue forward and a little bit towards the left the left genioglossus will protrude the tongue forward and a little bit to the right so let's follow this issue here hypoglossal nerve it supplies the ipsilateral geniogloss is here so here's going to supply the right nucleus and right hypoglossal nerve supplies the right genioglossus the left hypoglossal nucleus and nerve supplies the left genioglossus for the sake of our diagram the lesion is involving the left hypoglossal nucleus and the nerve so if that's the case then hypoglossal nerve stimulates the genioglossus to contract and it'll cause it to protrude and move towards the left but because this left genioglossus is inhibited it doesn't have enough stimulation the direction of it protruding towards the right side is going to be inhibited it's not going to be able to move towards the right so because of that this movement here let's actually draw it like this this movement here of moving the left geniogloss is kind of causing the tongue to protrude towards the left what's going to happen here as we try to do this it'll move to the right it'll be able to move to the right but this guy will not be able to move to the left right so it's going to be inhibited now the right geniogloss is going to be unopposed so whenever the right contracts it protrudes it to the left whenever the left contraction protrudes it a little bit to the right but now that right generosis is going to be unopposed and overpowered and it's going to start causing the genioglossus on the right to cause the tongue to protrude more towards the left so what does that present like so for example if i were to kind of show you i'm going to have my tongue right if i had a lesion involving the left hypoglossal nerve when i try to protrude my tongue that left side is going to be weak right it's not going to be able to treat it to the right which way is the tongue going to go it's going to deviate to the side of the lesion what's that side the ipsi lateral side so it's ipsy lateral tongue deviation let's write that down so beautiful when things make sense right so ipsilateral tongue deviation okay so that would be indicative of more of a lower motor neuron in this aspect more of the hypoglossal nerve lesion if it was upper motor neuron it'd be a little bit different okay so that covers that let's move on to the next one the next thing that is damaged here is that medial meniscus so if the medial meniscus is damaged what will happen here so let's talk briefly about the medial laminiscus okay obviously we know that the medial meniscus is important for carrying sensations what kind of sensations i'm glad you asked so you have here muscles right these muscles are gonna have some spindles right some muscle spindles that are going to be connected to your muscle like your connector your muscles your joint tendons your joints your tendons your joint capsules ligaments all those sons of guns and it's going to be sending information about the position of your muscles your tendons your joints in space and what it does is it sends this information into your dorsal root ganglion comes into that posterior gray horn doesn't synapse on a first order neuron here it doesn't synapse on a neuron here comes into that dorsal white column and then ascends upwards into the medulla right same thing it also is picking up sensations from the skin what kind of sensations it'll be picking up fine and discriminative touch vibratory sensations as well and sending that information via this pathway now what happens is is that eventually this will ascend upwards right it'll synapse on what structure here it'll synapse on the different nuclei for example this is the fasciculus gracilis let's say here we have the fasciculus cuniatus it'll synapse on the nucleus cunatus and the nucleus gracilis then what will happen is the nucleus gracilis and the nucleus cunatus will give off their axons that'll then cross over to the contralateral side and ascend upwards right and ascend upwards as the medial meniscus we have the medial luminiscus here so let's follow the lesion it's on the left side right here got to follow it back contralateral so there's contralateral so here's the lesion on the left side the sensations that we lose is on the right side that's the contralateral side so what are we losing well we're losing contralateral loss of position sense right so it's contralateral loss of proprioception and find a discriminative touch it's contra lateral loss of what sensations proprioception vibrations and touch vibrations here we'll put a comment vibrations and touch sweet that covers that okay so we cover what happens with hypoglossal so far it's ipsilateral tongue deviation contralateral loss of proprioception touch and vibrations what's the last structure damaged here the last structure that's damaged here is the corticospinal tracts so the cortico spinal tracts as you guys know this is our descending motor tracks they're sending information as you would know there's going to be up here's the pretend this is the cortex so that's our upper motor neuron it's sending down the descending information right coming down through that internal capsule moving through the crust cerebri moving through the ponds as it moves through the ponds it gets kind of moves into the medulla right and as it comes to the medulla at the bottom of the medulla in this pyramids this is the pyramids right as it gets to the bottom what does it do it crosses and kind of crosses here right so this will then do what it'll descend downwards into the lateral white column louder white column 85 percent of the fibers will and eventually it'll synapse on these lower motor neurons because this is our upper motor it's our upper motor neuron these were our lower motor neurons all right comes down descending cortical fibers moves through the midbrain through the pons through the medulla crosses that kind of lower part of the pyramids moves into the lateral white column and synapses on these lower motor neurons these lower motor neurons then go via alpha and gamma motor neurons to your skeletal muscles and cause these muscles to contract now where's the lesion the lesion is right here on the left side involving that corticospinal at the most rostral portion we said it crosses caudally though so let's follow this lesion oh contralateral side the lesion was on the left the weakness because this muscles aren't going to contract the weakness is going to be on what side on the right side the contralateral side so what is this contralateral hemiplegia okay so contralateral hemiplegia or hemiparesis hemiplegia is paralysis and paresis is more of the weakness okay so contralateral just put weakness contralateral weakness okay sweet so someone says medial medullary syndrome what part of the medulla is affected medial what vessels occluded anterior spinal artery what are the three structures damaged hypoglossal nucleus and the nerve medial limb meniscus corticospinal tracts what are the three presentations ipsilateral tongue deviation contralateral loss of proprioception fine touch and vibration and contralateral hemiparesis or weakness all right so let's cover the last lesion here this is going to be lateral medullary syndrome why is remember this was primarily supplied by what structure the anterior spinal artery more of this portion was supplied by the vertebral artery the most lateral kind of posterior aspect here was supplied by the pica and that was the other one that i wanted you to remember so the pica is going to be the vessels that is going to be occluded and cause damage to the structures in this portion of the medulla the lateral portion of the medulla so this is called lateral medullary syndrome you guys are so intelligent so lateral medullary syndrome okay so lateral medullary syndrome is going to involve what type of structures in here okay what what do we call these guys so we had hypoglossal nucleus dorsal nucleus of vagus nucleus attractive solutions what do we say was neck next the medial vestibular nucleus the inferior vestibular nucleus the nucleus ambiguous the descending sympathetic tract the spinal nucleus and this the spinal tract the inferior cerebellar peduncles your dorsal cochlear nuclei and your ventral cochlear nuclei all those things oh what else do we got here spinal meniscus so lots of structures are damaged here in this lateral aspect of the medulla so again vestibular nuclei we're going to cover that one first so let's see what happens whenever there is damage to these structures how will the patient present so there's a occlusion of the pica damages the lateral medulla it's going to affect the vestibular nuclei so what happens here what is kind of the presentation well really quickly what does the vestibular nuclei do you guys remember from the millions of times we've talked about it that this guys are going to be the superior medial inferior and lateral vestibular nuclei right and they're receiving information from what structures the inner ear right so they're receiving it from the cristae and they're receiving it from the macula right and that's the inner ear structures they're picking up dynamic equilibrium they're picking up static equilibrium so motion they're going to send this information to these vestibular nuclei right via the vestibulocochlear nerve the vestibular nuclei do what from there they do a bunch of crap they can send information upwards right to what things they can send information to the six nerve nuclei you guys know that you guys got the six nerve nuclei here and then you get the third nerve and then you got your fourth nerve nuclei right and what happens is when it stimulates this six nerve the six nerve will then do what it'll send fibers upwards and cross right and what is this thing's called that's our medial longitudinal fasciculus right that helps to conjugate our eye movements so that's one thing we also know that it sends information into the cerebellum to help with letting the cerebellum know of the you know basically our equilibrium sense it also sends information downwards to our skeletal muscles to help contraction of the anti-gravity muscles or extensor muscles so it does a lot of stuff so whenever there's damage to these vestibular nuclei some of the big things that you want to remember here is that whenever there's damage to a lot of the things that are connected to the inner ear it's going to produce this sense of loss of equilibrium or kind of a disequilibrium and that can present as vertigo okay and sometimes with vertigo people kind of have this you know the spinning sensation they can have an associated nausea and vomiting associated with it so what are the ways that the patients would present they might have some effect of the eye so there might be some type of diploplia maybe from some skew deviation but the big thing that i want you to remember is that it's really going to be having some disequilibrium which will present with vertigo okay so it'll present with vertigo and this is more of a central vertical we'll have another video on that someday and associated nausea and vomiting we'll write it shorthand okay so vertigo nausea and vomiting and maybe some diploplia because you're affecting this kind of this medial longitudinal fasciculus there may be some type of like potential skew deviation but again vertigo nausea vomiting is what i'm really looking for here okay all right good next structure the next thing that we damaged is we go here media vestibular nucleus inferior vestibular nucleus what else did we hit we got those cochlear nuclei those sons of guns got busted up too what do they receive information from they receive information from the inner ear as well but they receive it from the spiral organ of corty this is the inner ear structure the cochlea which is responsible for hearing not equilibrium hearing they send information to these cochlear nuclei via the vestibulocochlear nerve the cochlear nuclei do what you guys know this already some of the a dorsal acoustic striat will just go straight up the ventral acoustic striate will actually kind of come up and synapse on what's called the superior oliveira nucleus same thing over here synapse on that superior olivery nucleus and then ascend upwards right but either way these fibers that are sending upwards here that are coming up here this is all a part of what structure the lateral luminiscus right so this is the lateral meniscus lateral meniscus this would be the right this would be the left the big thing that you guys should remember is what are the cochlear nuclear responsible for hearing and because of that there's going to be again damage to these cochlear nuclei so if you have damage to these cochlear nuclei they're sending sensations about hearing where is it going to it's going to these cochlear nuclei so what happens is the connection to the spiral organ of cordy is damaged here they're going to have some type of deafness a kind of a sensory neural deafness but it might be more predominantly on the right side so what else can they present with because you damage these cochlear nuclei they may present with more of a kind of a unilateral sensory neural deafness okay okay so there might be a little bit of deafness vertigo nausea vomiting let's move on okay we hit the medium an inferior vestibular nuclei with the cor the cochlear nuclei we got that orange structure what is that son of a gun that bad boy right there is going to be the descending sympathetic tract you guys remember in the hypothalamus there's a sympathetic portion and there's a parasympathetic portion we're going to say that this portion this blue portion here is the sympathetic nervous system portion there's nuclei in here that are going to connect and have these descending fibers that are going to move downwards through the midbrain through the pons through the medulla into the spinal cord and give off some axons to some of the pre-ganglionic motor neurons that are present here in the the portion of the spinal cord from t1 to l2 right and what happens is these preganglionic motor neurons will eventually move upwards through the you know the uh all the different ganglia within the neck right it eventually goes up to what's called your superior cervical ganglion and the superior cervical ganglional synapse on these guys this is your postganglionic motor neurons and they'll move out and supply parts of the eye they'll supply for example this the the muscle of the actual pupil the dilator pupili it'll also go over here and supply one of the muscles of the palpable that helps a little bit with elevating the eyelid and it also can go and supply some glands on the face right so here we'll make like a little gland here it also can supply some of the sweat glands in the face now if you damage this track let's say that this is on the left side so let's say that this is that left descending tract if you damage the left descending tract the left pupil is not going to be able to dilate so the left pupil won't be able to dilate the left upper eyelid won't be able to elevate and the left side of the face won't be able to produce sweat so what will this present as you know what this is called this is called horner syndrome so this is called horner's syndrome horner's syndrome is characterized by again what is it whenever you have loss of the dilation it's constriction this is called meiosis what else you're also going to have loss of some of the ability of the muscles of the palpebra to elevate there this is going to cause ptosis of the upper eyelid so this is going to cause ptosis and you're going to have a little bit of loss of sweating on that side as well that's called anhydrosis so they can present with meiosis ptosis anhydrosis this is horner syndrome and this is going to be on the left side nausea vomiting vertigo unilateral sensory neural deafness and horner syndrome okay cool let's move on now we got this kind of greenish structure here that i want to cover this is your spinal nucleus and spinal tract that are connected to the trigeminal nerve do you guys remember the trigeminal nerve here we have what's called the trigeminal ganglia which sits outside of the kind of central nervous system and here it has its different divisions it has the ophthalmic division v1 it has the maxillary division v2 and the the mandibular division or v3 and it goes and supply sensations primarily v1 v2 are going to be more of the sensory aspects v3 is going to have a motor division as well but they supply most of the sensations on in this case let's just say that this is the left side of the face so they're going to supply proprioception pain temperature vibrations pressure all those sensations of the face then they're going to send that information inwards to these nuclei which again what is this nuclei here in the midbrain for the trigeminal no that's the mesencephalic nucleus what is this nucleus in the pons that's your central or principle ponte nucleus of the trigeminal nerve and the one that we care about here in the medulla is the spinal nucleus okay of the trigeminal nerve well what did we damage the lesion is on the left side so we're going to damage this is that spinal tract right we're damaging the left spinal tract and we're damaging the left spinal nucleus that means that all the pain temperature touch pressure vibration sensations that are being carried from these divisions on the left side of the face is lost so you lose sensation right there's a loss of what there's a loss of ipsilateral loss of sensations on face right and again that is going to be because of the spinal nucleus and spinal tract being damaged on the left side because again this is taking the sensations from that side of the face in this case the left side of the face okay we covered that so again so far we've hit the cochlear nuclei that we damaged right so this was our cochlear nuclei that we damaged and then we talked about the sympathetic tract that was damaged all right and we talked about the trigeminal nucleus that are damaged right so we talked about the trigeminal nuclei that were damaged and tracked now let's move on to the next thing so the next thing that we're going to cover here is this next one so this blue structure here what is this blue structure that got damaged we called that the nucleus ambiguous we're not going to go over all of this in depth it'll take forever to do it but what i want you to remember is that the nucleus ambiguous is a part of its fibers that will exit out here of the medulla it's carrying what kind of fibers this is very important it's carrying special visceral efferent fibers do you guys remember what special visceral efferent fibers supply your pharyngeal arches and this nucleus ambiguous its axons are actually going to be incorporated from this into a specific uh three cranial nerves so what happens is the nucleus ambiguous has three cranial nerves that its axons are carried on what are those three cranial nerves we have cranial nerve nine that's the glossopharyngeal nerve we have cranial nerve 10 that's the vagus nerve and we have a teensy bit of cranial nerve 11 the accessory nerve these three nerves their axons are carried from the nucleus ambiguous these special visceral efferent fibers and they're part of what's called the pharyngeal plexus and the pharyngeal plexus is going to supply the pharynx it's going to supply the soft palate in uvula it's going to supply some of the larynx and this is very very important that we understand this right so they're supplying the muscles of these areas so they're supplying the muscles of the soft palate the salpingo pharyngeus the stylopharyngeals the plateau glosses the palatopharyngeus the tensor velipalatini all those muscles they're supplying the muscles of the larynx right the intrinsic laryngeal muscles the cricopharynges the cricothyroid they're supplying the pharyngeal constrictor muscles all those things what is the significance of these well if you remember the soft palate in uvula whenever they contract they elevate and block off the nasopharynx which is important during the swallowing process right so there's going to be so there's going to be ipsilateral weakness of soft palate and uvula okay so that might have some problems whenever they're trying to swallow right so basically whenever they swallow what does that soft palate nebula do again they elevate they block off the nasopharynx that food doesn't get regurgitated into the nasal area the nasopharynx and nasal cavity so that's one important thing it also supplies the pharyngeal constrictors so if the pharyngeal constrictors are damaged what happens to them they're not going to be able to contract very well and push food down the pharynx into the esophagus so there might be some degree of dysphagia so maybe some oral pharyngeal dysphagia what else there's also going to be a damage to the actual nerves that are supplying the larynx right so because it's supplying the larynx muscles you know the larynx has the all the intrinsic laryngeal muscles all the cricoarytenoids and the cricothyroid and the cricopharyngeals all those muscles that are really important for helping with speech in the articulation of speech those are going to be damaged so now the ability to speak is going to be affected that's dysphonia and maybe the ability to articulate might also be affected so there might be some degree of dysarthria so there might be some dysphonia and there may be some degree of dysarthria so again i want you to remember these big things that the maybe weakness of the actual soft palate on one half there might be some dysphagia some dysphonia and some dysarthria let's move on okay the next one that we got here this is going to be for this kind of maroon structure guy the spinal liminiscus right so we hit the nucleus ambiguous now we're going to hit the spinal meniscus so now we're going to hit the spinal meniscus spinal liminiscus what happens here you guys remember this picks up pain temperature what else uh kind of crude touch and pressure sensations right from the body goes to a dorsal root ganglion from here it goes into the dorsal gray horn synapses on the dorsal gray horn right and crosses over if it goes into the lateral white column and ascends that's the lateral spinothalamic tract right if it goes into the ventral portion in the sense that's your ventral spinothalamic tract and again there's also that tectospinal i'm sorry the spinotectal tract but eventually the spinotectal the ventral and lateral spinal thalamic tract will fuse together and form the spinal meniscus that will ascend upwards through the medulla the pons and the midbrain and eventually to the thalamus well where's the lesion the lesion is on the left side and this portion of the medulla boom is damaged follow it back it's going from the left crosses over to the right that's contralateral so contralateral loss of what type of sensation sensations does the spinal liminescus carry there's contralateral loss of pain temperature crude touch and even pressure on the contralateral side of the body right so contralateral loss of pain temperature crew touch and pressure sensations that is important because we've damaged the spinal meniscus all right so now we have here again the last part here is our inferior cerebellar peduncles right and that's going to be the connection between the medulla and the cerebellum middle cerebellar peduncles between the pawns and the cerebellum and then the superior cerebral peduncles between the midbrain and the cerebellum what we damaged is this left inferior cerebellar peduncles the big thing that you guys need to remember is that the inferior cerebral peduncles is receiving tons of sensory information right it's receiving sensory information from your spinal cerebellar tracts like the cunio cerebellar tracts it's receiving it from the dorsal spino cerebellar tract it's receiving it from like the uh spinal olivary tracts there's tons of different tracks that are ascending and putting the sensations going from proprioceptors going from touch receptors all these different things that we have unconscious awareness of taking it to the cerebellum if you damage the connection between our body's position sense and the cerebellum it can cause a sense of gait instability or some ataxia and that is important so what else can these patients develop if you damage their left in this case inferior cerebral peduncles you're taking away the connection to the sensations of the body and this is from that side of the body right so ipsilateral ataxia that's important and again that's because of the damage to the inferior cerebellar peduncles all right niz nurse so in this video we talked a lot about the medullary lesions right we talked a little bit about the blood flow we quickly recap some of the anatomy of the medulla i hope this video made sense i really hope that you guys enjoyed it and learned a lot if you guys did smash that like button comment down in the comment section and please subscribe also if you guys get a chance down the description box we'll have links to our facebook our instagram our patreon all those things you guys want to keep in contact with us we truly appreciate it all right engineers as always until next time [Music] you