right today we are going to talk about cavernous sinus in detail right cavernous sinus is one of the dural venous sinuses so before really I go into detail of cavernous sinus i would like to mention that what is the basic concept of dural venous sinuses what are dual venous sinuses I will make you a very simple diagram that lets pulse it it's a very simple diagram let's suppose this is your cranial cavity okay here are your ears I cannot make a simpler diagram right now actually three neol cavity inside is lined with dura mater what is the meaning of dura mater dorsa dura Salwa lunatone omni rakia his right dura mean hard tough mater mean madonna actually it's a tough mother which protect the central nervous system so he is very right so now what we can see dura mater basically has two layers one layer which is very faithful faithful to what faithful to the bony internal bony lining so the faithful layer of dura mater I can draw it with okay green color right or which okay red color now this red color of dura mater this is red layer this is very very sticky with the bone it is very very sticky with the bone and wherever bone goes it goes with it right this is very very faithful kind of layer of durometer right so it is covering and interior of the interior of the cranial cavity right now but it has one more layer with it right there is second layer is also dura mater but that is less faithful at some places it departs from the route the second layer which is also their first I will make it very simple this green layer this is also the layer of dura mater and this layer is called yes which layer meningeal layer right this layer is meningeal layer the green one is meningeal layer and this one which is sticking with the bone this is called periosteal layer but such periosteum which is lining inside of the bone that part of erestrum is called endosteum so we can say it is also an Austrian layer so this layer is which layer and Austrian layer right actually it is periosteum but that very Austrian which is lining the skull from inside that is called endo still so now what we have learned that dura mater is one of the meninges right and durometer has two layers one is industrial layer which is very faithful with the bone it is a sticky layer it is a sticky layer like a very faithful wife right and other layer is like a girlfriend you know what is that let's faithful right even though try to get along with but this layer this is called meningeal layer right now why I say it is less faithful because at some points it may separate right detached from the industrial layer right and made some sort of infolding right for example it moves like this and like that this is just an example or at some other place it moves away from here and become like this in this way when this meningeal layer of dura mater less faithful layer of the dura mater more this layer when it detaches right away from the end of Steel layer a gap is produced right and this gap right this gap is usually filled by the venous blood right there the purpose in this unfaithfulness also that here actually venous blood right venous blood is entering into this space period in between the two layers off your arm at ER and this venous blood is coming from where mostly it is coming from Sarab cerebral Hemisphere right this venous blood is coming it is coming also from the bones around this area it is also coming like of thermic veins there are this remains communications but basically this is so what we can say now this space which is created by separation of two layers of dura mater and full of what venous blood right this piece is called dural venous sinuses what is it called dural venous sinuses so what are dural venous sinuses dural venous sinuses are very specialized venous channels right present intracranial ii right created by separation of industrial and manage a layer of dura mater and thrilled with the venous blood and lined by lined by lined by endothelium wherever in our body blood is there if you don't want blood to clot it has to be endothelial lining so what we can say now I'm going to enlarge it that let's suppose this is our vision layer is now I'm going to enlarge only this area endosteal and let's suppose what was this layer going yesplease meningeal and here it was little bit departing and space created in between them is full of venous blood and this is called dural venous sinus the important point which you need to remember that this layer this whole channel or space is lined by endothelium right and the pineal cells you know they are very 4/10 they help the blood not to clot right not to clot so basically now we can add one more feature that dural venous sinuses our endothelium lined special spaces created between the two layers of dura mater and one more area now if this is V s channel most of the Venus channel in our body have valves most of the venous channels in our body have valves right but dural venous sinuses rather the question should be which dural venous sinuses have valves no Diller sinus has very very good no this is true these are not having anywhere so it means that it is possible that in dural venous sinuses if around them are inside them local pressure changes blood can flow in either direction right so these are valves less they don't have any well i am i clear after this so this is what is the basic concept of dural venous sinuses right now central nervous system has many dural venous sinuses but today we will specifically focus on cavernous sinus right so let's go and talk about the cavernous sinus first of all I would love to mention that in central nervous system or in the cranial cavity exactly where the cavernous sinus is located right first we learn the exact point where it is located so let's suppose from my do you like my haircut it's a new haircut I tell you brand new ok so why I remember it because I want to give you a concept that if you remove the cranial vault and remove the brain out out of that and then look inside right you will look at the base of the skull is there right from inside and how it will look if you are removed most of the things from inside right it will look something like this ok so oh my it's not balanced but anyway no problem world is also not balanced I'm making just these structures so that you know that ears are on the side and hoses in the front and here a few now when you draw the cranial cavity base this is a central structure here what is it cilantro chica very good and from here greater means of sphenoid or the lesser windows fee night night less servings of sphenoid right and here it is what it was part oh my god why you are after the greater windows fee night that is not here that is somewhere here right we'll talk about that later okay so what is this Petros part of temporal bone right now if we really if you can identify these landmarks right now you must be knowing these are and clear trillion or four see these are middle cannot foresee these are fostering of fuzzy and of course you know the big thing here what passes through it spinal cord or brain stem or really possible it's the end of the brainstem and beginning of the spinal cord but don't tell anyone has so biggest passage from the area's right okay so Wow so this is the seat now this is the base of the cranial cavity somewhere here cavernous sinus is located right exactly where actually Cooper the sinus is located on the side door what sella turcica right of course a little Sheikh has the top of the body of sphenoid bone so there is one given this sinus here right this is one cover the sign is here looking to you and other cover the sign of this here look into you so where are the cover no sinuses we can say they are situated in middle cranial fossa just on the yes lateral side of the which seller predict not cilantro Zika more Tori speaking from the lateral side of body of sphenoid and pituitary gland is that right now this is the location right now so where it extends in 10th row posteriorly let me make it rotated and I'm going to now draw my cover the sensors with this view right and if I make that it should become something like this you know a big brain but I never intended to make a big nose anyway so here it is yes now you understand what are the structures I've made there's no fun in telling it is crista galli and you hear it it's cribriform plate of ethmoid bone and of course you know that here is your eyeball am i right your many balls and these are a balls and then okay let me make it a little more bigger for you so this is what you're spinning right now cavernous sinus one should be on right side and other should be on the left side so there are two cover no senses which are paired structure at the in the middle cranial fossa now interiorly this is the orbital cavity this one and of course there's other orbital cavity of that side right and here there the structure what is this very good I'm impressed by some of you you know Fischer is also superior orbital fissure right now speed orbital fissure is here on both sides keeper the sinus basically extend okay before I go to detail what was this bone petrous part of temporal bone and here also this is petrous part of temporal bone right now for the sinus explained from now I'm going to draw it here this is the top of the cavernous sinus right now cavernous of course there's another side also there's no fun in telling you you know it already by now now cavernous sinus anteriorly it approaches which structure superior orbital fissure right and posteriorly it extend up to that tip of the clitoris part of temporal bone right so we can say cavernous sinus are paired structures which are dural venous sinuses created by a separation of two layers of your matter they are situated on the sides of a finite body of sphenoid and pituitary gland right they interiorly they extend up to the superior orbital fissure and posteriorly they reach up to the tip of the which was part of temporal bone it's almost 2 centimeters long and 1 centimeter wide is that right it's 2 centimeter long and 1 centimeter wide now this is the basic structure now I will make a diagram from the side right and we'll go into detail effect any question up to now it was just a basic concept what is cavernous sinus why we call it cavernous sinus any question call it given asanas no one want to answer me what is K were spaces actually Cuban asanas he's very right to burn our sinuses having lot of you can suspicious or caverns right it looks like if you cut the cavernous sinus right it will choke radicular structure right and because it has multiple channels within it right within the cavernous sinus there are multiple what caverns but what are exactly those governs let me tell you let me tell you before you tell me something new cavernous synapse is called covertness sinus because it's cavity is full of full of very thin walled and athelia lined pubes and spaces right so it is not one space it is just like a one box having many many cubes inside it and many many spaces inside so we can say governor sinus interiorly or internally has a meshwork of meshwork of venous channels and the phillium line right because a multiple channel that they are inter communicating and when we cut them they look like tribal structures we call them they are like lot of worms inside it caverns mean small caves small spaces to call it cavernous sinus does that right so anyway now cover the sinus we know the basic exactly where it is present let me tell you how it is created a little more detail right there how exactly it is created it means already you know that to create a cavernous sinus two layers of durometer should become unfaithful and depart from each other now let me draw the yes body of sphenoid bone right and here there is greater wing on the here is a Tetris part of temporal bone going on the side and then you know that you have ears on the side is that right I don't know maybe okay support something here so that females can be happy okay now here we have to see how the cavernous sinuses exactly produced right there was sticky layer and austrial layer faithful layer it's moving towards this side right it remains faithful with these bony structures even if there is a foramen here what are the foramen exactly under the cavernous sinus which is the forum and just under the cover on a sinus foramen lacerum very good why we call it less room because it is less irritated see irregular excellent so anyway there is foramen lacerum here but I'm talking about endo still layer right and the still layer faithfully goes from petrous part of temporal bone medially runs over the body then from here moves and in this way it goes to the other side also right now what is this layer and Austria right with it other is moving what is this yesplease meningeal layer now as meningeal layer is approaching initially they are together as it approached what is this spin at born right before it here it becomes unfaithful right and it depart from there and it goes fee really right it goes upward and when it is going upward it really goes upward and then it moves medially right but it doesn't stop here not at the top it moves more than expectation medially and then it comes back and moves here right and again now again it becomes faithful for a while is there right but you know it's a little naughty okay so again it will depart and make a beautiful fold here and then it will go go go and eventually it will come down and then it's become faithful and sticky with that layer so now you can see cavernous sinuses are created like this you understand exactly how they are created right that basically and or still layer remain with the sphenoid bone and with the base of the what is this middle cranial fossa but as middle layer approaches right it detaches from the end of still layer right and it moves speedy early then medially right and eventually making a special fold here and then coming down and again they become together at this space which is the top of the body of the sphenoid the top is called Sela tell chika right why we call it set sella turcica why we call it cilantro chika Turkish saddle Turkish saddle who is riding on the saddle which would Wrigley and the chairman of Endocrine Society is there right Sophie chotek land is here this is stock of pituitary gland and here it is which you rig land over here is that right now this part of meningeal fold which is making a the yes overhanging over the pituitary gland this is called diaphragmatic all this component is called diaphragmatic as a central aperture through which the pituitary stock goes upward and of course it gets connected under what how very good hypothalamus excellent now this is how Adams made now let's define the walls actually if you define the walls now on board in our lecture we will consider this setup floor of cavernous sinus what is that floor of cavernous sinus which is made of industrial layer part of a median wall is also made by and Australia right and lateral wall is made by yes meningeal layer roof is made by meningeal layer very good and part of upper part of medial wall is also made by manon jelly now you exactly know how it is made dural sinuses right so in the same way it is here right that roof is made by meningeal lateral wall by the meningeal floor by industrial and part of the middle lower part of the medial wall by industrial and upper part of the medial wall made by manager done Claire okay now we know where cavernous sinuses are situated what is the size and dimension and how exactly they are made now we see what are the structures important structures related with cavernous sinus