hello and welcome to Insight oftalmology I am Dr Amrit welcoming you to another lecture today the topic is wnal kerto conjuntivitis or vkc in this video we shall be focusing on the signs symptoms and classification of vkc first of all what is meant by wec wec stands for Vernal kerto conjunctivitis it is a chronic bilateral interstitial allergic inflammation of the cornea and the conjuntiva both and typically it present in younger individuals these individuals often have an atopic background that means they usually have an underlying asthma or eczema or one of their family member has history of allergies although I say that patients with vacc have an atopic background don't confuse this with atopic ker conjunctivitis which is an entirely different entity the onset of disease is usually in the first decade and it then it usually lasts uh most still puberty and then resolves during the late puberty however adult weaky is also seen now this is more common in case of boys compared to girls and also it's common in dry and hot weather although it is also known as spring Qatar it is usually a misn normal since you see this disease in basically dry conditions it is more common in tropical areas near to the equator its highest incidence is reported in African country with incidence decreasing in direct proportion from the distance from Equator so as you go away from the equator the incidence of veral kto conjunctivitis basically goes down so what did I tell you that vkc basically is seen in case of dry and hot weather and such weather conditions you are going to find near the equator okay so tropical countries have greater incidence of VCS then next comes a subtropical then comes a temperate and then almost in the almost the vacy is non-existent in the colder areas now in our first video on allergic conjunctivitis we talked in detail about the allergic conjunctivitis and also the pathophysiology of the allergic conjunctivitis now in this video we shall be covering some additional points regarding the vkc let's talk about how does wec occur so usually there would be a presence of of any chronic allergic stimulus in the form of an outdoor or indoor allergen now this usually leads to mass cell degranulation now this we have discussed in the allergic conjunctivitis video as well apart from the mass Cell Activation and degranulation in vkc you are going to find that there will be overactivity of t- helper cells too now usually in our body we have t- helper cells on and t- helper cell two response the t- helper cell 2 response is responsible for allergy and t- helper 1 is something which has a suppressive effect on t- helper 2 all right now the mels are going to degranulate and they are going to cause release of the histamines cyto and proteases the T helper two response is basically responsible for generation of cyto kindes which are like interlukin 4 interlukin 13 and they are responsible for the production of IG from the lymphocytes this is very important now because these histamin cyto protasis and the the interlukin have been released now what will happen all the inflammatory cells will get recruited to the conjunctiva and the cornea and these inflammatory cells basically are iils lymphocytes neutrophils all of them are going to now migrate to the Cora and set up a chronic ongoing inflammation in case of VC now in this point at this point I want you to remember that there's an overa T helper two cell response there is mass cell degranulation and also you can remember at this point that when we talking about vkc we are talking about both type 1 and type four hypers sensitivity reaction all right moving on now there will be a chronic inflammation that will be set and because of that there will be persistent inflammatory cell infiltration and at one point the fibroblasts are going to get activated and now these activated fibroblast are going to start proliferating and they will form fibrous cells in the conjuctival stroma okay so in the substantial appropriate region you will have excessive proliferation of these fibr cells and as they proliferate they are going to deposit certain extra cellular matrix extracellular means that they are going to deposit some material in between these cells okay this could be collagen or other proteins and this process ultimately is known as heniz or thickening of the conjunctiva we'll talk talk about hyalinization in a while all right now apart from that certain other growth factors are also going to be released these will be transforming growth factor beta wedf and platelet derived growth factor now because of these growth factors you will see some modeling going on within the conjunctiva and within and here conjunct by conjuntiva I mean both the Bulba conun Diva and the tarel conun divver okay because in the anatomy of video or uh in the video on anatomy of conjuntiva I told you that conjuntiva basically has two parts it has Bulba conjunctiva and then you have a palpable form of conjuntiva so all these changes are going to occur in both the conjunctivas all right so because of this remodeling there will be formation of elevated nodules and these nodules are known as papila okay so usually a papilla will have the central vascular core a central blood vessel surrounded by inflammatory cell and the overlying epithelium will undergo hyperplasia and hypertrophy okay so this is something which is responsible for multiple papill that you see in the upper tassel conjunctiva in case of vkc all right now let's understand some of the path some of the pathological changes so what did I tell you in the epithelium what will happen in case of vkc there will be hyperplasia hypertrophy and this epithelium is then going to start growing downwards like this within the substandard but within the uh underlying substantia proia or the subepithelial tissue okay then there are changes which are going to occur in this uh sorry in this layer and this is called the adenoid layer what will happen in the adenoid layer you will see marked cellular infiltration that means a lot of cells are going to come into this edoid layers mostly you have to remember iils because they are very dangerous apart from that plasma cells which will secrete IG lymphocytes and the hioides which are nothing but macro phases what will happen in this layer here so this layer is the fibrous layer normally it will have the fibros sides now because of chronic inflammation there will be deposition of extracellular Matrix collagen and ultimately there will be hyalinization so what is heniz now heniz in any tissue refers to a pathological process wherein the tissue will become homogeneous okay of same color it'll become glossy it'll have have a glassy appearance to it and it'll be iophic when viewed under the microscope when I say ionophilic I mean to say that it'll have a pink appearance under the microscope and why does this heniz occur this heniz basically occurs because of deposition of protein such as collagen and other extracellular Matrix component and why does it occur because of chronic inflammation which is going on now it need not be vkc it could be a respon to injury or a response to a chronic degeneration also okay but right now we're discussing we apart from that you will see changes in the conjuntival blood vessel so there will be increased permability and vasod dilation okay so remember these four pathological features associated with vkc this is important for undergraduates all right so you can see over here this is how a papilla basically looks and again you can see these elevated nodular lesions here in the upper task conjuctiva so on EV verion you can see these elevated lesions so this is nothing but this is a this this is basically a papillary reaction so I hope you know what's the difference between a papill and a follicle okay so over here you can see in a in a papula basically you will have a central blood vessel and surrounding that blood vessel you will have lymphocytes and lucos sites however in case of a follicle you will have lymphocytes and other cells sitting in the center and the blood vessles are going to grow basically from the either side of it okay so based on in conjunctivitis what do you see whether you're seeing a Pap or whether you're seeing follicular reaction you can actually classify conjunctivitis into different types okay we have discussed about that in this video on conjunctivitis papilla versus follicles and the membranes so the link to all the important videos will be provided in the description box now let us talk about the clinical features of Vernal kerto conjunctivitis that is the signs and the symptoms first let us discuss the symptoms the wec is characterized by marked burning sensation and itching sensation which is usually intolerable and accentuated when patient comes in a warm dry climate or warm dry atmosphere right and this itching is more common in palpable form of vacy so we'll talk about what is palpable form and what is Bulba form of vacy but know that it's ing is more common in the palpable form of vacy apart from that there will be photophobia and sometimes you can see this white stringy ropey discharge and lacrimation so what is this ropey discharge ropey discharge is nothing but you will have the strands of mucus in patient's eye that can actually stretch like a rope when it is or like a string when it is pulled or wiped away okay so this type of discharge is caused by excessive mucus production due to the chronic inflammation of the conjuntiva which is going on in v KC all right apart from that patient will also have foreign body sensation and this usually happen because of the presence of papilin they will have heaviness of eyelids and why is that happening again because of presence of Pap sometimes the pap will become so heavy and that those papill can actually uh cause tosis or maybe sometimes patients have excessive itching so they might damage their muscles in the eyelid leading to drooping of the eyelid known as tosis okay sometimes response to the allergic photo allergic reactions and in response to photophobia patient might also have ple spasm right apart from that they will have pain and dimition of vision usually if corneal involvement is present so as such if only the conjunctiva is involved these patients will not have any dimin of vision it only happens once the cornea gets involved so remember in kerto in Vernal ker conjunctivitis we have two terms we have a keratitis and we also have conjunctivitis that means there's inflammation of the cornea and also the inflammation of the conjuctiva so once your cornea gets involved it is when you will see deinition of vision okay I hope that is clear all right now let's come to the signs of veral kerto conjunctivitis based on the signs that you see you can divide vkc into three types basically you have palpable form of vkc then we have bulbar form of vkc and we have a mixed form of vkc apart from that you can also have vacy with coral involvement now you have to remember one thing that in v in vacy or Vernal kerto conjuctivitis usually the skin of the eyelids is not involved okay so whenever you see skin of the eyelids also getting involved along with allergy it basically means that you are actually looking at a patient of AKC and not vkc AKC is atopic kto conjunctivitis so what I mean to say is in atopic KOC conjunctivitis you have involvement of the skin of the eyelids but in wec you usually do not have the involvement of skin of eyelid so I hope that is clear all right now let's talk about the palpable form of VC as the name suggests palpable form of vkc basically means that your eyelids are going to be involved now what are you going to see on the eyelids usually it is the upper tarel contiva which gets involved and here you are going to see presence of hard flat toped papill which are arranged in a pavement Stone fashion and this is called as the Cobblestone appearance now you some books call it as flat top papill however there this is there's a slight discrepancy over here because in giant papillary conjunctive iters also you're going to find papill however it is believed that although both of them have flatter papill the papill of wey are going to be slightly more roundish compared to the papill of AKC okay now these papill can be associated with Ry discharge again you can see over here this is the ropey discharge all right now these papill are basically arranged very close to each other just like a just like the stones in a pavement are basically arranged and that's why this is known as Cobblestone appearance or the pavement Stone appearance now let me tell you that whenever you see upper tassel giant papill usually in a younger patient associated with itching and other signs it's usually typical of vkc all right coming to grading of Pap so how do you grade Pap we can grade it based on the size of Pap we have grade one grade two and grade three grade one is when the size is between 0.1 mm to 0.3 mm grade two is when the size is between 0.4 to 1 mm and grade three is when the size is more than 1 mm grade three is also known as giant papill now let us discuss some important clinical pearls in association with the U Pap so first one is the Maxwell lion sign so what is meant by Maxwell lion sign over here in Maxwell lion sign you're going to find fibrine deposition along with the papilin so this fibrine is going to be deposited in the form of a pseudo membrane so when you see pseudo membrane Plus papill in a in a case of vkc that is referred to as the Maxell lion sign if you have made it this far into the video and you are enjoying the content I have a small request for you please don't forget to hit that subscribe button and click on the Bell icons to stay updated with all our future videos did you know that only 50% of our viewers are subscribed to our Channel let's change that your support means a lot and helps this channel grow allowing us to bring more valuable content like this thank you for being here and let's keep learning together the important clinical Pearl is that whenever you papul specifically in milder diseases you have to stain the patient with flosin why because sometimes even in a milder disease you are going to see excessive epithelial stippling and the the palpable conjunctiva is going to take up the stain now the importance of fluoresent staining is that it basically indicates the activity and severity of vacy so if you're seeing a papill which is taking up the stain it means that those the underlying pathophysiology is active in this patient and this patient might actually need a very active anti-allergic treatment or you can say anti-inflammatory treatment we'll talk about treatment later on all right so remember epithelial staining basically indicates activity and severity in a case of vkc another clinical Pearl is with regard to the location of papill so when you see papill in the upper tasel conjunctiva it is more common in case of Vernal kerto conjunctivitis whereas when we talk about atopic Ker conjunctivitis the papill might still be seen but these papill are more common in the lower tasil conjunctiva okay now so we discussed now about the pable form of vkc also known as the tarsal form of vkc moving on to the bulbar form of VC and we can call it as the limble form of VC as well so what are we going to see over here here obviously the Bulba conjuntiva or the area around the limbus is going to get affected so you might see Dusky red triangular congestion of Bulba conjunctiva in the palpable area now this is important for undergraduates because it's given in their textbook Dusky red triangular congestion so you can see over here this might be a triangular congestion that your textbooks are talking about okay so usually you will see those triangular congestions near the limbal area so remember I told you that we see papilla in the tel conjuntiva so you can also see papilla formation in the limble area or in the Bulba conjuncta now these papilla however are going to be more gelatinous and they can fuse with each other to form these confluent areas of limble hypertrophy now these Pap are known as a limble Pap and remember they have a mucoid appearance or they have a gelatinous appearance to them sometimes what you're going to see is that you will see this small white chalky nodules sitting on top of those papilla or sometimes those those papill might totally be capson and you will just see the small white chalky nodules along the limbus and these are known as the Horner trantas spots okay so this is very very important now the limble nodules or the limble pap that you see they basically made up of the lymphocytes plasma cell macras and all the other things but important over here is the Horner tranta spots okay so in the first picture you can see limal hypertrophy and congestion what do you see over here again there is limble gelatinous appearance to the limbus so maybe they were papill here and now they have become confluent here you can see those chalky white dry looking uh excen and these are nothing but a h and trantas dots again here's some sort of uh limble changes and what is more prominent here is the reddish congestion area okay so here you can see these uh uh separated mucoid nodular areas around the limbus so these are basically your limble papill okay don't call them Hornet r dot Hornet R dots is only when you see those chalky precipitates on top of the nodules here maybe here at the top of the nodule you actually see those horr dots all right so what is the importance of these Hornet trantas dots now Hornet dots basically indicate active disease just like the fluoresent staining so when you see a horr dot it basically indicates a SE severe disease and why is that so because these horr dots are basically made up of degenerated epithelial cells and isops and these isops secrete a lot of epithel toxic enzymes like the ionophilic basic protein milin basic protein catonic protein ionophilic peroxidase and they are highly toxic to the coral epithelium at the limbus so they can damage your limbus and ultimately they can lead to Super ficial corneal neovascularization panis formation and they can also cause corneal melting and that is the reason why the Hornet ranta dots are more uh dangerous okay so we discussed about the palpable form we discussed about the Valar form let's move ahead to the mixed form of we casc the bulbar or the limal form is usually most common commonly seen in Asian and African population however the palpable form is commonly seen in Europe and us the mixed form however is more common in the tropical countries and more so in the Indian subcontinent with the incidence being about 72% so most of the cases that we seeing over here in India are of mixed variety of vkc all right now let's talk about the coral involvement so there is an ongoing inflammation going on in the Bulba conjunctiva and in the tarel conjunctiva so because of that inflammation ultimately they there will be release of mediators and these mediators can actually cause some toxicity to the epithelial cells of the cornea leading to punctate epithelial erosions then these erosions will Quest together to form larger areas of erosion important over here is that the Bowman's membrane will remain intact right so that is important now if the condition is untreated these might actually progress to development of a full-fledged ulcer and the ulcer over here is referred to as the shield ulcer and sometimes in in some of the papers I have seen um it is also known as the tobe's ulcer or Tob ulcer okay so again you can see over here these epithelial erosions which are taking stain with the Florin so the case of VC it's very important that you examine the patient under the cobalt blue filter after fluin staining all right so this ulcer is referred to as the shield ulcer and the shield ulcer typically affects the uh it typically affects the lower border of the upper half of the visual axis so you can see this if you divide it like this uh pupil okay so if you BCT draw a line bisecting the pupil the upper part of the cornea will be affected by the shield ala so this doesn't mean you won't find Shield ala in the inferior quadrant it's also it can also be found in the inferior quadrant but it's usually rare okay so now over here let us understand these pictures so here you can see a giant papilla papilla present over here and just below the papilla you can see the border of an epithelial defect over the cornea so at this stage it is just an epithelial defect if you do fluoresent staining it will take up the stain now after slightly lifting up the lid you can see this is a slit lamp image the slit has been passed through that defect and what do You observe the upper part seems to be greater uh seems to be showing greater illumination or you can say the upper part of the or the upper border of the epithelial defect is slightly more opaque and then in the third picture you can see there's a progressive ulceration of the same defect and here you can see this has now become like this is actually a ulcer all right now sometimes you might just have an Alca like this but sometimes with a ongoing inflammation there will be inflammatory debris and mucus which is going to get deposited over the ulcer leading to the formation of a shield ulcer with plug so this white thing that you see is actually a plaque okay now important fact about the plaque is that the plaque is made up of the mucus tissue and also made up of the dead tissue and therefore it is going to prevent the epithelial ends or the epithelial margins from growing inverse that means it's going to stop your epithelial healing and therefore in most of the cases of shield aler with a block it's important that you debrite the plaque and you clear the base of the ulcer sometimes even freshening up of the margin of the ulcer might be needed so we'll talk about the uh treatment of The Shield ulcer later on so just remember debridment is needed in Shield ala with a plug so Shield ala is basically named behind this Shield okay that the soldier is carrying and important fact is that you have to treat the shield also because if it the thing is that it can leave a corneal scar it can get infected and if it is if basically if it encroaches the pupilary area it can also lead to diminish visual it all right and do you know that we can also grade The Shield aler this is so we'll talk about the grading of the shields aler it is divided into a b c d e and f d and e represents grade two okay so in a you will have diffuse punctate epithelial erosions B is macro erosions in the Superior part C is when you see an epithelial defect but the base is transparent D is when you have the epithelial defect but the margins are more opaque than the b e is when the base is more opaque than the margins and F is when there is an opaque elevated plug so let's Zoom this so you can see multiple erosions here this will be a here you will have macro erosions in the superior aspect B this will be your C in which you can see the ulcer but the ulcer is a trans has a transparent base don't think this is greenish in color it's because of the floresent staining probably it's transparent because you can see the underlying a pupil and the iris now again here you can see in this D what is what has happened you have an ulcer but the margins of the ulcer are more opaque than the base here the base is more opaque than the margins and ultimately you can see this plaque formation okay so in the end I will talk about pseudo toxon also so here what happens is that with chronic inflammation going on there will be a gray white superficial stromal deposit position which will be seen in the periphery of the cornea and this is referred to as pseudo toxin true true Geron toxin is seen in case of old individuals where you have the lipid deposition and that is also known as the Arcus analis okay and in Arcus analis you will basically have a bilateral lipid deposition whereas in sudoer and toxon which is seen in bkc usually you will have unilateral Pudo toxon and this will not be symmetrical and it fluctuates over time okay so this indic creates a chronic uh healed state of uh your vkc so here you can see this is active disease and this is more of a coent disease with a pseudo jeren toxon on top and usually in vkc you will have a superior pseudo toxon apart from that periocular pigmentation can also be seen and this is again a sign of Kronos chronicity okay so when you see pigmentation in a case of VC you can uh you can basically uh deduce from that that the inflammation is is chronic now can you classify VC based on the severity of the disease yes so based on severity we can classified it as mild moderate severe and blinding disease and based on the periodicity it could be labeled as intermittent or chronic so what is meant by intermittent disease so intermittent periodicity basically means that the patient has fewer than four episodes per year so basically VC keeps on coming in episode so sometimes it might even be present throughout the year right so intermittent means that patient has less than four episodes per year and each of these episodes will be followed by complete remission that means the patient has complete uh the patient becomes totally well in between these episodes and that period of U remission it usually should last for at least one month okay to to be called as remission I hope that is clear and then we have chronic periodicity chronic periodicity means that the symptom is are present all year round and the remission periods if any are basically less than one month and therefore we don't count them as remission we call it as a chronic uh type of periodicity okay so this classification basically has been taken from the Indian Journal of Opthalmology by Dr nikl s go so you can see mild vacy is only when the symptoms and papill are present moderate intermittent variety is when symptoms papillate and along with that hard trantas dots are also present and you might see some amount of sp sp is nothing but it is superficial punctate epithelial erosions so we talked about the keratopathy keratopathy aspect of the VY so that might be seen along with that you will see focal limal inflammation but the inflammation is less than six clock hours here okay so this is moderate intermittent then in moderate chronic because of the chronic nature of the disease the patient would also develop Cobblestone appearance in the tasel Conca in severe disease what will happen apart from the Cobblestone the anular limble inflammation now will be more than six clock hours so what do I mean by anular limble inflammation I mean to say the gelatinous appearance of the limbus will be more than 6:00 hours right apart from that the SP and pek that is the punctate epithelial keratopathy and superficial punctate epithelial erosions all of those are going to be Co now that means greater area of the cornea is being involved here you might see conjunctival granulomas and also the limbal deficiency might be developing so what happens is that after some time because of the chronic inflammation there will be damaged to the limble stem cells so that will cause limble stem cell deficiency and the limble stem cells will also prevent the growth of the concal vessels on the cornea but now since the limble stem cells are damaged there will be growth of concal vessels on the cornea and that is known as panis okay it's not just the vessels but also fibrous tissue apart from that macro erosions can also be seen in severe disease okay so now in blinding disease you will have various other things as well like you will have a shield ulcer you will have lscd that's limbal stem cell deficiency with conjunctivalization vascular corneal tarer and also tarcel scarring so more amount of scarring going on in case of blinding disease so let's talk a little bit more about the blinding disease in wkc so again you can see over here vessels growing on top of the conjunctiva conjunctivalization of the cornea okay okay so if along with VC you find limble stem cell deficiency if you see the growth of panis on the cornea if you see presence of korus yes we is associated with korus there might be thinning of the cornea and corneal elasia in v vacy and one theory is because of the constant rubbing of the eye that happens in wec also there might be various other growth factors that are released we have discuss about that in the pathophysiology so we have those uh growth factors released in the tears and they can go the cornea and they can also call corneal Remodeling and thinning okay and sometime the epithelial defect because of the kot toxicity of the isoil basic protein there might be persistent epithelial defects also and also because these patients would be mostly on what do you say steroids these patients can also land up with cataracts and glaucoma right so when wey associated with all these things we call it a blinding disease okay and so in a patient of vacy always pleas make sure that you check keratometry and topography to rule out cornal ectasias you check intraocular pressures to rule out glaucoma particularly it be a steroid induced gloma in these patients check the status of lens to rule out Cataract and also check the status of optic dis why because these patients might also develop glaucoma and there might be optic neuropathy or what do you say optic cupping or changes basically glaucoma optic this changes in these patients okay all right another grading system is that of Bon Min this was uh this basically came in 2007 if I'm not wrong okay so you have this grades here again five grades are there basically we refer to four grades and grade zero is basically qu and face grade one is mild intermittent grade two is moderate again intermittent persistent grade three is severe and grade four is very severe okay so you can go through this and in grade four you can see basically you are going to have severe disease that means Hornet trantas dots will be present and coral complication will be there like erosion and ulceration so when you get erosions and ulceration it becomes very severe okay and in severe you can see cornea is involved but only spks are present this is the same bu classification just a different way of presenting it okay so you can go through it so you can see again in the severe and very severe disease you can have superficial punctate and cordial erosions horat tranta dots are basically absent it starts coming up from the severe and very severe disease all right so that was for today and I hope you enjoyed this video kindly give it a thumbs up and don't forget to subscribe thank you and have a nice day