hello and welcome to inside Opthalmology this is Dr Amrit welcoming you to another lecture today we are studying the ocular blood supply so in this video we shall be talking about the Opthalmic artery and its branches important relations of the Opthalmic artery and and certain important clinical nuggets blood supply of the retina blood supply of the optic nerve and the optic tract blood supply of the choid blood supply of the eyelid conjuntiva and the blood supply of the extraocular muscles trust me it's going to be easy as long as you follow along and not skip the video in between so let's get started so this is a wonderful image showing the cores and branches of the Opthalmic artery from the netas atlas but to understand the branches we need to really dissect this image and look at the individual components of the Opthalmic artery one by one so now let us simplify the image to break it down further let's look at this diagram and let's start labeling a few structures here so this is your lacrimal gland then we have the lateral rectus present in the lateral part of the orbit we have the optic nerve the internal cared artery which is situated here then we have the superior oblique in this diagram this is the medial wall and the ethmoid sinus which is present in the medial wall of the orbit and this spine structure this spine like structure here is the anterior kinoid process now it is very important to know that the Opthalmic artery basically takes its origin from the internal cared artery and the internal cared artery enters the skull through this foramin here which is known as the foramin laerum now the Opthalmic artery basically arises from the medial aspect of the internal calid artery and then it passes medial to this anterior kinoid process and that is why I mentioned and talked about the anterior kinoid process before now the Opthalmic artery after it's it actually takes its origin from the internal cared artery that you can see over here okay it passes medial to the anterior kinoid process and gives its first branch and that first branch is actually the central retinal artery now the central retinal artery as you can see in this diagram is basically traveling below the optic nerve for some distance and then it enters the optic nerve by piercing its Dura matter archid matter and the Paya matter so as we know that the optic nerve is basically covered by the three sheets which are also covering the brain so your duramat aroid and the pomatter are also covering the optic nerve so the center retinal artery basically travels for some distance below the optic nerve and then it is going to uh take a turn upwards and Pierce the sheets around the optic nerve and enters within the substance of the optic nerve and this happens basically at a distance of 10 to 15 mm from the eyeball and now it travels straight within the optic nerve and reaches the retina now the course of the central retinal artery for which it was traveling inferiorly in the Dural sheet surrounding the optic nerve and till the time it reaches the retina so that part is actually known as the extraocular part of the central retinal artery and now it is going to enter the eyeball through the lamina crosa which is the fenestrated portion of the Scara and through the lamina crosa it is going to enter into the RNA over here as you can see we have this opening in the Scara which is called the optic cup and in the nasal part of the optic cup is basically your central retinal artery situated now this is going to basically give you two branches Superior and inferior the superior branch and inferior Branch are going to further divide dichotomously and they're going to give a nasal branch on the superior side which is called a superior nasal Branch another Superior branch on the temporal side which is called Superior temporal branch and then we also have two branches inferiorly an inferior nasal and an inferior temporal Branch okay now these branches further keep on dividing dichotomously up to up to the AA cator the part of the central retinal artery which has come up to the retina is basically called the intraocular part of the central retinal artery the intraocular part basically is coursing over the surface of the retina and is actually it is basically situated superficial to the gangon cell lay now this these branches are actually going to send some other branches within the layer of retina and it is going to supply the inner six layers of the retina so this is one very important point that the retina basically has 10 layers however the inner six layers of the retina are basically supplied by the central retinal artery okay and another important point that you must remember is that the central retinal artery is basically entering at the nasal end of the optic disc and then it is going to give further branches like the superior and the inferior trunk which are further dividing into the superior nasal Superior temporal inferior nasal and the inferior temporal branches now another point that you must remember is that these branches of the central retinal artery they do not supply the fobia instead the phobia is supplied by the selary circulation or the coral circulation and about that we will be talking in detail in a while okay so remember the inner six layers of the retina are supplied by the central retinal artery but the fobia is not supplied by the central retinal artery it is supplied by the coral circulation or the selary circulation okay now this would be actually a correct time to discuss an important clinical nugget regarding the central retinal artery occlusion now briefly what happens in central retinal artery occlusion is that because of several reasons the central retinal artery can get uded and therefore the blood Supply uh to the center to the retina will actually be uh hold will actually come to a Hal and because of that decrease in the blood supply because of central retinal artery occlusion you will see retinal edema okay and this retinal edema basically gives a pale appearance to the retina because there is edema and also there is decreased blood supply to the retina however as we discuss that the central part of the retina or the fobia is basically supplied by the coral Circle culation and in central retinal artery osion the cidal circulation is normal right so as the cidal circulation is normal the central part of the retina or the phobia will actually retain its normal reddish orange appearance whereas the surrounding retina is going to look paler in appearance and because of which the central red normal for wheel area which is supplied by the seary circulation is going to appear as a cherry red spot okay so that is one IAL nugget regarding the central retinal artery occlusion where you're going to see a generalized retinal edema along with a central cherry red spot now approximately in about 20% of the population there is actually a branch of the celery circulation which is called a celor retinal artery okay so the celor retinal artery is not going to come from the central retinal artery instead as a name suggests it is actually coming from the cery circulation but it is coming right up to the r Rea and supplying The Superficial layers of the retina like this and it is going to come out from this temporal end of the optic nerve and Supply the area between the temporal part of the optic nerve and the macula okay now in this 20% of the population uh who has cilo retinal artery if they actually suffer from a central retinal artery osion what will happen although the blood supply will be cut off because C retinal artery occlusion the area the macular area will now be spared and the patient will have good Vision because of the normal celor retinal artery okay so that is one important clinical nugget that you have to remember so if this artery is present which is present in about 20% of the population the central vision will be preserved even in a case of central retinal artery occlusion so we discussed the first branch of the of the Opthalmic artery so this is the internal cared artery from there we have the Opthalmic artery basically it's going to travel from below and give basically the first branch and that is called a central retinal artery also referred to as the arteria centralis retina so if you want to know in detail about the blood supply of the optic nerve the optic nerve head I would advise you to visit this video on the blood supply of the optic nerve the link is going to be present in the description box now moving on the Opthalmic artery uh which was traveling inferior to the optic nerve will now take a turn and come out lateral to the optic nerve here as it comes out in the lateral compartment of the orbit it is basically situated as you can see medial to the muscle here and this muscle is the lateral rectus apart from that the third cranial nerve which is the ocular motar nerve and the sixth cranial nerve is also present lateral to the the Opthalmic artery along with the selary gangion so what are the structures which are present lateral to the Opthalmic artery as it comes out in the lateral compartment the celer gangon the third nerve the sixth nerve and the lateral rectus muscle okay now the Opthalmic arter is going to actually give a branch in this lateral compartment and this Branch as you can see is going and supplying the lacrimal gland and this branch is referred to as the Lal artery okay so the Lal artery basically travels at the upper border of the lateral rectors and supplies the lacrimal gland now also another import important point that you must remember is that the lacrimal artery will give a branch which is called as the lateral palpable artery which is basically going to supply the lateral aspect of your eyelids okay apart from that these lateral palpable artery are also going to form arcades in the eyelids and Supply the uh eyelids so more about it in a while so here as you can see this is the Opthalmic artery it has actually appeared in the lateral compartment and then it has given this branch laterally which is reaching up to the lmal gland which is called the lcal artery and the lacrimal artery inter turn is giving these two branches which are the lateral palpable artery so it's very simple to remember it's very easy to remember remember L for lacrimal artery and L for the lateral palpable artery and they are all situated in the lateral compartment of the orbit moving on another branch that the Opthalmic arter is going to give in the L in the lateral compartment is the recurrent menal artery okay so this is the Recine menangel artery now this Recine menangel artery which is a branch of ofic artery which is in turn a branch of the internal cared artery is going to come out through the superior orbital fish and we talked about the superior orbital fissure in detail when you were talking about the anatomy of the extraocular muscle okay so if you want I will link link down that video again in the description so this Rec menal artery is going to actually travel in the lateral part of the superior orbital fissure and it's going to reach the dura matter and there it is going to estos with a middle menel artery which is a branch of external cared artery so if you're an anatomy student you would know this is actually a common question that is asked that uh you know mention the locations where the internal C artery and the external C artery anastomosis takes place okay so this is one location of anastomosis between the recurent menal artery and the middle menal artery wherein the recorded Manel artery is a branch of internal CD artery and the middle Manel arter is a branch of external cared artery now the Opthalmic artery now decides that she's going to travel above the optic nerve okay so it's going to cross now above the optic nerve and as it crosses the above the optic nerve it now is going to reach the medial compartment of the orbit and here in the medial compartment of the orbit it is basically accompanied by two structures Superior of thalmic vein and one more nerve that is the nasos cerine nerve okay and this of uh this Opthalmic artery is basically traveling below the superior rectus muscle so on top if you see an axal section of the orbit this diagram is basically an axal section so on the top or Superior most you have the superior rectus below that you have the Opthalmic AR artery and below that you have the optic nerve okay so here uh two important branches that are going to come out from from the Opthalmic artery that you can see over here these wavy branches on the either side of the optic nerve they are very important for us and these are called the selary arteries or the posterior selary arteries now as you can see in this diagram also these wavy branches on the either side of the optic nerve these are basically your posterior selary arteries so very very important so basically in both the eyes you have two posterior selary arteries one which is present on the lateral aspect is called the lateral posterior selary artery abbreviated as the lpca then you have one which is present on the medial aspect is called the medial posterior selary arteries now these posterior sary arteries are going to further divide into numerous branches now two branches are going to actually travel a long distance and they are going to reach they going to travel in the supracal space space and reach right up to the celer body where they're going to Anastos with the anterior selary artery to form the um major arterial Circle okay of the iris whereas a few of the bran a few branches will have a short distance and they're going to terminate here behind in the posterior region and these are called the short posterior arteries okay so to summarize you have basically two trunks of the posterior CER arteries medial and latal then they're going to keep on dividing into multiple branches of course a lot of those branches are going to terminate shortly thereafter which are called the short posterior C arteries and two branches one medial one lateral is going to travel a long distance in the supracal space to reach the selary body and form the major arterial Circle and those are called The Long posterior selary arteries so if you can see over here in this diagram also we have long posterior C arteries we have short posterior C arteries and then we have a few short posterior cery arteries which are going to form a plexus around the optic nerve which is called the circle of Zen andher so let us see so first we shall be talking about the short posterior cery arteries right so they are basically arising as two Trunks from the Opthalmic artery and then they're going to divide into these 10 to 20 branches now an important Point regarding the short posterior celery arteries is that that they're going to pierce the sca near the optic nerve and then they're going to supply the choid in a segmental manner okay so they have the segmental distribution of the short posterior celery artery however some of the branches are going to form a plexus around or you can say not plexus really an anastomotic ring around the optic disk which is called a circle of Zin and Hala okay you can see short posterior selary artery around the optic nerve which is called the par optic short posterior celer artery then you have the long posterior celer artery one at 3:00 one at 9:00 position that is horizontally they are present there are no long posterior sary artery vertically okay and then we have some short posterior CER arteries which are present on the either side of the optic nve the short posterior CER arteries basically Supply the choid as far as the equator and along with that it supplies the outer four layers of the retina so what are the outer four layers of retina we have the retinal pigment epithelium which is the outermost we have the layer of photo receptors the external limiting membrane and the outer nuclear layer so here this image actually tells you regarding the circle of Zen and Hala and if you could notice these two branches here are the short posterior or the posterior C arteries you can see all these anastomotic blood supply is most of it is actually coming from the posterior sary arteries or the short posterior sary artery okay the central retinal arter is traveling in the center of the optic nerve and then supplying the retina and as it supplies the retina we can also say that it supplies The Superficial head of the optic nerve whereas most of the area of the optic nerve in the lamina cribrosa and also in the retr lamina region is being supplied with the posterior celery artery so more about this I've explained in the video on blood supply of the optic nerve now this would be a very important U time to discuss a clinical nugget on the anterior isic optic neuropathy now the oval that we discussed about or the anastomotic ring that we discussed about that forms circle of Zin can actually be divided into Superior portion and inferior Portion by the entry points of the medial and lateral short celery arteries which are forming it okay so the celer arteries which are coming like this they're going to form the Sur Circle so arbitrarily you can divide it into a superior portion and an inferior op inferior portion now this may be the anatomical basis for the altitudinal visual field laws that we see in case of the AI or the anterior isic optic neuropathy so what is anti kic optic neuropathy it is basically a disorder that happens because of the nonperfusion or hypoperfusion of the selary blood supply to the optic nerve head so when the central retinal artery get uded which is called Central retinal artery occlusion you will see a pale retina because the retina is being supplied the inner six lers of the retina are being supplied by the centralal artery whereas the celery circulation is supplying the outer four layers and most of your optic nerve and therefore when the celery circulation is affected the optic nerve head is affected and you will see that dis edema moreover because the celery circulation has a segmental origin or it has a segmental supply usually you will see either the upper half or the lower half of the optic disc will be affected in the form of optic dis edema and if you go ahead and do and a visual field you will see that there will be a hemispherical Field Effect and this hemispherical Field Effect is known as an altitudinal Field Effect so in this picture basically you have the inferior part of the disk affected and therefore you are seeing a superior field defect now here important high yield point that I would like to mention is that the inferior field is more often affected okay because of the preferential involvement of the Superior part of the Ring of vessels okay so Superior part of the optic disc is affected more and therefore an inferior Field Effect is more common in AI o n okay there there is no adequate explanation for that but remember that AI n is it basically leads to an inferior Field Effect because of the Affliction of the Superior part of the disk now another clinical nugget regarding the celor retinal artery so by now I hope that you understood what's the cro retinal artery and what are those celery arteries and where are they coming from now those celer arteries which are coming from behind they can actually send a vessel and that vessel can actually enter the retina from the temporal part of the optic disc and Supply the area of the maula so that is called a celo retinal artery because it is coming from the celery circulation and supplying the retina sometimes the celor retinal artery will get uded and therefore you will see this pale retina in the area which is supplied with the c retinal artery whereas sometimes as we know that both of them are coming from the C circulation or the posterior sary arteries what will happen is that the celor retinal artery along with the short posterior CER arteries will get uded and then you're going to see a picture of pale appearance or edatis dis along with this pale retina so this is a combined occlusion of seal retinal artery and anterior isic optic neuropathy right now what will happen if there is an Opthalmic artery occlusion so if you know the answer give that answer in the comment section so I'm expecting a lot of answers after this okay so again if you want to know more about it you can refer to the video on blood supply of the optic nerve so we discussed about the short posterior sary arteries now let us move ahead and talk about the long posterior sary arteries so what did I tell you we have just two long posterior celer arteries which are coming from those posterior CER arteries and one is coming on the middle aspect one is coming at the lateral aspect that means you have at 3:00 and 9:00 one one long posterior CER AR now they're called long because they have a long course they pierce this CLE obliquely and then they're going to enter the supracal space reaching the celer body Now by now I expect all of you to have uh visited those three videos on the anatomy of Iris anatomy of selary body and the anatomy of choid because only then you will understand what exactly am I talking about so what is Supra choroidal space right and so these long posterior C arteries basically travel in the suid space and reach the anterior aspect of the of the sary body here and if you would notice they do not give any branches in this course Instead at the anterior end of the C body they are being joined by these arteries which are traveling along the muscles and these arteries are the anterior celer arteries and both of them are going to join together and form this anastomotic circle around the iris which is called the major arterial Circle so you have the anterior C arteries and then you have this long post arteries coming from behind and then they are going to both join together and form the major arterial circle now to summarize the blood supply by the or via the celery arteries you can see this diagram so here this circle actually represents your Equator so if you see the part of the retina that is the outer four layers of the retina and the part of choid which is situated posterior to the equator is basically supplied by the short posterior celery arteries whereas the part of the retina and the choid which are anterior to the equator are basically supplied by the posterior celer artery that is the long posterior sary arteries so the long posterior CER arteries basically Supply anterior to the equator whereas the short posterior CER arteries basically Supply posterior to the equator and when we are talking about the retina you have to remember that the central retinal artery is basically supplying the inner six layers of the retina that is your internal limiting membrane the nerve fiber layer the gangon cell layer the inner plexiform inner nuclear and the outer plexiform layer so that forms total six inner retinal layers whereas the posterior celer artery or the celery circulation or the coral circulation will basically Supply the outer four layers of retina that is the outer nuclear layer the external limiting membrane the layers of photo receptors and the retinal pigment epithelium now it is very important uh to remember that the vessels are actually although the four layers that is the outer four layers are supplied with the coral circulation the coral vessels are not present in the outer four layers of the retina because if there were Coral vessels present in the outer four layers of the retina that would actually interfere with the vision and that would actually be a pathology that is actually actually called Coral neovascular membranes okay so when I say that the cidal circulation is responsible for taking care of the outer four layers of retina is basically by the means of diffusion of nutrients and metabolic based products and not per se by the infiltration of branches of the coral vessels into the outer four layers of the retina so there is one very important point that you must remember so with this we finish these two branches of the Opthalmic arteries that is the posterior cery arteries so now let us revise we have the internal cat artery which is giving the Opthalmic artery then the Opthalmic artery was giving this arteria centralis retina or the central retinal artery then it gave a lateral branch called the lacrimal artery the lacrimal artery gave two branches the lateral palpable arteries then we have the two posterior celery arteries which formed the short posterior celer arteries and the long posterior CER arteries so moving ahead we know that these Vel are now going to cross the Opthalmic arter is going to actually cross on top of the optic nerve now and as it travels on top of the optic nerve it gives one branch and that Branch basically travels above the superior rectus and the lator palp superioris okay and this branch is basically the supraorbital artery okay so the supraorbital artery is usually accompanied with the superorbital nerve and it travels above these above these major muscles which are present in the superior aspect the superior rectus and the levator palp superioris it basically travels just below the orbital roof and then it comes out through a notch which is present in the superior orbital rim and that Notch is the supraorbital notch okay so this artery that you can see here which is coming out of the sua orbital Notch is a superorbital branch of the Opthalmic artery now two more branches come on the either side as the ofic artery travels on top of the optic nerve and these are called the muscular arteries so we have a medial muscular artery and lateral muscular artery the medial muscular artery is basically going to supply the muscles which are present on the medial aspect and what are these muscles these are the medial rectus the inferior rectus and the inferior obli whereas the lateral muscular arteries basically Supply the superior rectus the Superior or although they're present superiorly but still the lateral rectus and the LPS okay so remember the medial rectus the inferior rectus and the inferior oblique form one group and they are supplied by the medial muscular arteries whereas the superior rectus the superior oblique that is the superiors and the lateral rectus and the LPs they form one group and they are supplied by the lateral muscular artery so our discussion would not be complete if we don't talk about the anterior cery arteries and here we discussing about the muscular branches that means we talking about the blood supply of the extraocular muscles right so these muscular branches are actually going to give further branches and these are called the anterior cedary arteries right so the muscular arteries Supply the muscles VI the anterior cedary arteries and every muscle has two anterior CER arteries except your lateral rectus which is a loner which has only one single anterior selary artery so one this is very very important point that lateral rectus has only one anterior Cy artery whereas the rest of the muscles have two anterior C arteries now this anti arter is important because apart from supplying the extraocular muscle they also Supply your Scara conjunctiva and the limbal area okay they basically pierce the ca at a distance of about 4 mm M from the limbus and here they going to basically join the arteries which are coming from behind in the supracal space and those arteries are what are those they are the long posterior CER arteries so they join the long posterior CER artery along with the uh so the anti artery and the long post artery they join together at about 4 mm distance from the limbus and at the anterior end of the celer body they're going to form this circle of blood vessels which is called the major arterial Circle this major arterial circle is going to then send branches into the iris which are called the radial branches of the iris and these radial branches of the iris are going to form an anotic ring around the pupil near the CATE and form the minor arterial Circle okay so again it's very important for you to understand the anatomy of Iris in order to understand all what we are talking about so at this point I would like to mention a clinical nugget regarding the anterior segment ishia okay so these anterior celer arteries they're very very important because here we're talking about the major arterial Circle and the minor arterial Circle these major arterial Circle are actually responsible for the perfusion of your anterior segment and in this the 70% of the blood supply is coming from the anterior sary artery and only 30% is being contributed by the posterior sary artery therefore whenever we uh whenever a patient under goes a squint surgery in which we are manipulating the muscles okay and if the surgery involves more than two rectile muscles in one eye the patient can land up into anterior segment ismia because of the damage of the anterior selary artery okay so it's always advisable that we do not operate on more than two retile muscle to prevent the risk of anterior segment hemia very important point now another important point to remember is that the posterior sary arteries which are augmenting these arterial circles they are coming from the horizontal direction that means we do not have any posterior sary arteries coming from the vertical Direction therefore when we do surgeries on the vertical muscle there is much more there is a severe risk of anti esmia compared to the surgery on the horizontal muscles because in the vertical direction we do not have those posterior C arteries which were contributing to 30% of the blood supply in the arterial Circle so moving on I hope you are with me by now so here what happened to the Opthalmic artery it crossed on top of the optic nerve and now it has reached where it has reached on the medial compartment in the medial compartment it encounters the medal wall of the orbit and over there we have two uh we basically have the sinuses which are called the ethmoidal sinuses and therefore they're going to give two branches these are the anterior ethmoidal artery and the posterior ethmoidal artery now these arteries are basically going to come out through the respective feramin that means the anterior ethmoidal foramin and the posterior ethmoidal foramin an important Point regarding the anterior ethmoidal um artery is that it's going to actually travel from the orbit straight into the anterior CR fosa and then it is going to come out again into the nasal cavity through the cribriform plate by piercing the cribriform plate and then it comes out outside on the external aspect of the nose between the junction or at the junction of the nasal cartilage and the um nasal bone okay so till here you have the nasal bone and here you have the nasal cartilage so at the junction of the nasal bone and the Nal cartilage it actually appears on the external aspect so as you can see in this diagram so here we have this anterior ethmoidal artery and here we have the posteroid artery so you should know that on the medal aspect we have these two branches now coming to the terminal branches so so now ultimately as the Opthalmic artery is going to reach the medial compartment it travels anteriorly and then near the tra of the superior oblique it is going to give its terminal branch es and these are the supr trar artery and the doil nasal artery okay the doil nasal is basically going to supply the dorsum of your nose so here as you can see we have this dorsal nasal artery which is coming like this okay so above that we have the Supra choar and the Supra orbital nerves okay so remember one nerve uh one artery which was coming out from the Supra orbital not that was a Supra orbital artery and then we have the supr trop clear artery and then we have the dorsal nasal artery right so these three arteries are present on top the dorsal nasal artery can actually give two branches and these are the medial palpable arteries one artery from for the upper eyelid and one artery for the lower eyelid at the same time do you remember I mentioned that we have a lateral palpable artery which is coming from the lacal artery which is originating in the lateral aspect of the Opthalmic artery in the lateral compartment of the orbit now these lateral palpable artery and the medial palpable artery are actually going to form these two arcades near the lid margin and these arcades are called The Superior and the inferior marginal arcade apart from that in addition to that we also have a peripheral arcade which is basically going to supply the foress area of the eyelid and that is called a superior peripheral archade okay so with this we have uh summarized the blood supply of the eyelids as well that that we have these arcades we have two arcades in the upper lid and we have only one single arcade in the lower lid and these are being formed from the medal palpable artery which is a branch of dorsal nasal artery and the lateral palpable artery which is a branch of the lacrimal artery so if you want to know more in detail about the blood supply of the islands in the conjuntiva H you can visit this video on the anatomy of conjunctival where we have discussed about the posterior conjunctival artery as well now the ocular circulation is not complete if you if we don't discuss the Venus Supply okay or the Venus drainage when we discuss about the Venus drainage of the eyeball we often come across terms like the vortex veins or the Venus vertico say now basically there are about four to seven Vortex veins okay in number so although the diagram shows four you have to remember that there are a lot of people who can have more more than four Vortex veins now there are usually two Vortex veins in the superior compartment they are called Superior temporal Vortex veins and the superior nasal Vortex veins okay so here you have the medial one which is the nasal and then you have the lateral which is the temporal then you have inferior Vortex veins similarly the temporal inferior and the inferior nasal veins now most of the time these Vortex veins basically can have a dilation at their ends and that is called a Vortex ve ampula very important when we talk about these uh Vortex veins they're basically situated in between the rectile muscle and the distance at which they are separated at which they are situated from the limbus is about 14 to 25 mm another important high he point now they're situated at that distance and they are basically also situated within the Scara in in a form of a canal so you have the small Canal within the Scara in which these are traveling and that scleral canal is about 4 mm in length important clinical nugget is with the location of the vortex veins ampula when seen on an indirect opthalmoscope so when you carry out an indirect opthalmoscope the ampula of the vortex veins can actually be visible and they're visible usually at a distance of about 8 to 9 mm from the aura Sera now if you actually draw an imaginary Circle drawn at The Vortex vein ampul as you see on the indirect of thalos opy so that imaginary Circle will actually represent your Equator so that is one important clinical nugget that the position of the vortex veins can actually indirectly um uh indicate the position of the Equator on an indirect of thalos scopy so this is a wildfield angiography image in which you can actually show this position uh you can actually see this position of the vortex vein this is how the vortex veins basic basically look like okay now important point is that the the uvia or the choid is basically firmly attached at certain positions to the Scara the Scara is the outer coat the uvia is the inner cat and the innermost quat is the reum the UA is firmly attached to the Scara at two positions one is at the Scaris sulcus okay and the other is at the ampa of the vortex veins and therefore what happens is that whenever you have separation of the choid or the UVA from the Scara because of presence of fluid in the supracal space you get this lobular appearance or the lobular appearance of the Detachment of the choid this lobular appearance occurs because the points where the vortex ve ampula are situated the choid is firmly adhered to the underlying Scara and fluid cannot penetrate at those locations and therefore the fluid is going to actually accumulate in this lobular configuration and that is the reason why you get this trilobular or quadr lobular appearance of a full flesh coidal Detachment now so we basically have these Vortex veins okay and these Vortex veins are actually going to drain into the superior Opthalmic vein and the inferior of thalmic ve now corresponding to your um anterior celery vein you also have an anterior sorry corresponding to the anterior sary arteries you have a anterior sary vein and we also discussed about this anterior sary vein when we were talking about the tabular mesh okay so these anti- veins they all going to go and drain into the Vortex veins Vortex veins are going to carry this um uh De oated Blood and they're going to drain into the superior of thalmic and the inferior of thalmic veins that is the superior Vortex veins will drain into the superior and the inferior ofic inferior Vortex veins will drain into the inferior of thalmic vein and ultimately along with the central retinal vein they're going to drain into the cavernous sinus so to understand that it's very important that you understand the clinical anatomy of Iris clinical anatomy of the selary body and the celer process and the clinical anatomy of the choid so all these videos are available on the channel so to end let us end with the clinical nugget regarding the choal diffusion so what is coidal diffusion choal diffusion is basically collection of the fluid in the Supra choroidal space that is a potential space present between the choid and the scera which is usually dry however ever in certain situations the Venus drainage from the eyeball through the vortex veins can actually get impaired now if you would remember the coidal veins or the vortex veins basically are traveling for about 4 mm length within the scleral canals now if you put a scleral band like seen in case of written Detachment surgery on top of the eyeball what happens these scal buckles or scal Bands Will basically compress your Vortex veins and the V drainage will will be impaired because of which there will be collection of fluid in the supracal space leading to Coral effusion now in some conditions like the U effusion syndrome you have a very non-compliant Scara the Scara here has increased thickness and very disorganized collagen fibers so these disorganized collagen fibers in the Scara are also going to impede or impair the posterior segment drainage by causing uh a compression on The Vortex veins and reducing the permeability of the Scara to the macromolecular substances leading to the buildup of fluid within the Supra choroidal space and leading to this choal Detachment or choroidal effusion okay so two reasons that you can get a cidal effusion is because of an external pressure which is impeding the drainage of the uh impeding the Venus drainage of the vortex veins or sometimes the scera itself is damaged or the Scara itself is non-compliant uh impairing the posterior segment drainage so that was all for today I hope this video added some value to your life if it did kindly subscribe to our Channel and hit that like button it makes a lot of difference for us thank you and have a nice [Music] day