 I'm just gonna kind of highlight some of the points on each slide, but you guys can have my slides and kind of review a little bit more of what What will be on the test? So we're just focusing on cornea and external disease today so on Anatomy they're probably still going to Ask you about the sort of three component to your film They've kind of changed their thinking on this in in the recent BCSC They just kind of say it's a it's just sort of a glob of all these things together But historically they've thought of the tear film as kind of three distinct layers So you get your lipid aqueous and mucin and they like to ask where each of them come from as well So that's a common question that'll come up The other question that I see commonly in in tests is how much how much tear production Is happening so two microliters per minute and it seems like everything is two And so it's kind of tricky to remember like the aqueous formation the aqueous outflow of the tear film production So you have to kind of get those things straight in your mind Some of these numbers they do like to test so they'll ask you if a Patient's cornea qualifies them for megalocornia or micro cornea And so you have to kind of understand what the corneal diameter is at birth It's about 10 and then as an adult you get up to about 12 It is a little bit wider in the horizontal versus the vertical you'll figure that out when you're doing pks You have to be a little bit more cautious about how you center a pk in the vertical meridian The power of the cornea they love to ask so the anterior surface is about 49 on the positive posterior surface is about minus 6 So you get the combination of about a plus 43 diopters for the total power of the cornea You'll kind of just this will kind of just make sense as you're more experienced in ophthalmology when you're looking at calc for IOLs The average corneal power is about 43 44 diopters And so just remembering that the posterior cornea has negative power The overall refractive index is another thing they bring up 1.33 They like to ask this really lame question that keratometry usually measures 2.3 millimeters apart So they just like to ask details sometimes The thickness of the epithelium again something that you'll learn as you're doing refractive surgery learning about that It's about 50 to 60 microns. It's hydrophobic. So the lipid Sort of cell membranes or they're rejecting fluid as they're trying to get into the cornea And so you've got the hydrophobic epithelium that kind of inhibits some of the Transmission of medications across the epithelial barrier They do sometimes bring up these three layers, but I don't think it's all that important The desmosomes sort of link the middle layers and you've got the hemi desmosomes they anchor the stroma to the bottom This comes up a lot Mamelists kind of pounds this into your brains that bowman's layers not a basement membrane There is an actual basement membrane of the epithelium that will be typed for collagen and stain with PAS So bowman's layers not a basement membrane. I think it's on like every test I've ever taken bowman's membranes about 10 microns thick It's type 1 collagen This is the other key to bowman's is that it usually scars if it's violated So if you get a an injury that's just epithelial, that's why you don't get a scar in the cornea has to go through bowman's You go a little bit deeper into the stroma the stroma is about 480 microns thick. It's mostly water If you get higher water content that about 78 80 percent then it starts to get opaque And thicken type 1 collagen is mostly what's there you've got type 3 involved in wound repair They like to ask those types of questions as well The kratocytes are what kind of turn into the scar forming cells in the cornea and lay down the type 3 collagen On pathology slides, they'll sometimes show you a picture of a Cornea and pathology and it won't have any little clefts in this stroma and that means that it's actually swollen So it's kind of it when it's when the collagen looks really compact. It looks it's actually a swollen cornea That's it for that slide pretty much they get that water content levels about 78 percent Decimase membrane pretty thin membrane 3 to 12 microns in thickness For some reason they like to separate the fetal banded versus the adult non banded part of the of decimase membrane I don't exactly know why but if you think about a fetus coming first It's the anterior part Versus the adult part, which is the posterior part and again, this is a PAS positive basement membrane So it'll it's type 4 collagen The endothelium is pretty thin as well 4 to 6 microns thick. It's just a monolayer cells At birth you've got a lot of cells 35 to 4,000 And then you get about 2,500 cells in the dole again You think about like ophthalmology the experience you're getting when you're looking at PKs You're looking at endothelial cell counts when you're doing transplants They tend to come in at about 2,500 to 3,000 cells and so some of your experience can help you So you don't have to memorize these things but Cell counts that sort of They like to bring this up as well when you're doing cataract surgery on somebody What is what cell count gives them a risk for corneal edema and the thought is that it's about a thousand And again with donor corneas we definitely want above 2,000 cells It's somewhere in the sixes it seems like it's different in a lot of different resources, but Yeah, I mean I have 680 micron corneas that are perfectly normal that I do LASIK on and so It's it's sort of a if you have somebody with Fuchs dystrophy if they're above about 650 then you're at risk so Okay, the sclera The thinnest point is right behind the muscles It's also thin right in front of the muscles. It's an on average about a millimeter thick in the post of your part It's mostly type one collagen. The reason why it's not clear is because it's irregular collagen Instead of the cordia, which is a nice regular collagen structure. That's a little higher water content as well you'll get these little plaques and tear to the muscle insertions and When they get dehydrated they'll look very thin when they hydrate they're a little bit thicker But these are normal aging spots that you'll see Again if the water content drops low, then it'll It'll become a little bit thinner and more see-through So just to summarize the collagen types so type one you've got bowman stroma and sclera type four It's always at the basement membrane So in the cornea you've got the basement membrane of the epicellium and then decimates membrane and then type three does your wound repair Okay, so inflammation of the conjunctivitis you've got follicles versus papillae. Sorry. These are kind of small but The common ones that I like to ask are about herpes and moluscombe for viral causes and then chlamydia of the follicles So the chronic follicular conjunctivitis, that's your main differential You can also have you can have benign folliculosis, but drugs can cause it as well And then there are some kind of unusual things that will bring it Bring it out also With papillae. It's a little bit more nonspecific a lot of times when I look at conge. It's a mixed reaction I just try to figure out which one's more prominent to help me understand what's going on So you'll usually see papillae and follicles in it when there's inflammation so Papillae the key is that it's a pinpoint blood vessel that's kind of centrally in the elevated lesions Whereas the follicles have sort of a dome shaped to them without a vascular structure right in the center And you usually think about bacterial infections in allergy and floppy eyelid so with Giant papillary conjunctivitis those are papillae and so if you flip the upper lid Got those really big cobblestone papillae. That's that's with some of these allergy things So chronic follicular conjunctivitis again the main things that they're going to test you on are herpes Moluscombe so make sure you're looking around the eyelid and lashes and then Chlamydia as well and some of these other ones are pretty rare flick tenuels Kind of interesting things. These are migrating inflammatory nodules on the surface of the ILC these in the corneal see them on the conjunctiva The thought is that these are usually probably in our country staff related So I usually treat these with a combination of antibiotic steroid if you have somebody who's been in an endemic area for tuberculosis You should think about that and test them for tuberculosis There are some other rare things that can come up. So PPD is kind of what you're thinking when you see a flick tenu and again, they're kind of I don't know they're they're not it's kind of a Trash bag diagnosis where it's like well some things on the congenital looks kind of funny But usually you've got a bunch of blood vessels coming up to an area of whitening that's kind of ulcerated and will stain It's usually pretty tender for the patient So degenerations of the corneally so marginal keratitis usually There it's it's kind of in that category if it's at the edge of the cornea honestly So it's kind of tricky to differentiate it exactly You'll still see vessels marginal keratitis tends to be A little bit more flat Than this this is usually a pretty elevated edematous nodule and it's most commonly on the conge So marginal keratitis is specific to the cornea But you can get flictenials that are actually that look like marginal keratitis. So they're kind of a Tricky to distinguish sometimes Most of the time on a test this will be on the conge. Yeah. Yep Okay, so degeneration so if you have a something that is normal and then it's sort of getting It's degenerating over time. You think about pinguicules and terrarium are the most common things But you can also get this ferroidal degeneration and the the limble girdles that you get kind of at the edge of the corneas that are not Band keratopathy, that's also a degeneration. So you'll usually see those at three and nine You'll get just a little whitening of the of the cornea and then conjunctival clases is something that we see really commonly So here's your hypersensitivity reactions is another thing that they like to bring up So type ones you just think about allergy It's mass cell driven Type two you're thinking about you've got antibodies and antigens plus complements So kind of the three together So you have ocp and morons classically is type twos and then type threes are antibodies and antigens with no complement activation and so Those are kind of the ones that you get in there and then so they love this faco anaphylactic in ophthalminus is a type three Type four we've got flictennials AKC can kind of be in both Because it can be a delayed reaction craft rejections classically type four you can also get that as a More acute type one type reaction to So granulomas commonly type four Sympathetic ophthalmin other one they like to ask about type four And then they've got this type five category where it's like a stimulating antibody engraves in my synia Kind of fall into there Okay, so they like to talk about stains and ask you about fluorescein versus rose bengal and what they're actually staining So fluorescein is essentially staining disruptions of cellular junctions And then rose bengal and the samine greeners kind of devitalized epithelial cells So they generally they don't have to be broken down So usually they'll stain things that fluorescein won't so they can kind of bring out more subtle things. I don't even have any I don't use it, but a lot of people like it AKC really common it can be pretty bad. You can get scarring there's the the Anteer subcaps or cataracts that you can get So don't confuse that with the the ulcer that's a sort of a vkc ulcer that's on the cornea Sometimes people mix that up. So corneal ulcers with vkc. You get cataracts with AKC These usually kind of wax and wane, but they're pretty much there all the time and And Can be kind of tricky to treat sometimes, but in kids you try to treat this with steroids sparing medications like tachyrolimus topically Otherwise you're kind of treating it with steroids and just dealing with the consequences and side effects a cornea That's vascularized and blind doesn't really Sort of matter if you have a develop a cataract, but you have a the trade-off Steroids you get a cataract or you get a corneal blind patient, right? So sometimes you just have to have room with steroids and take a cataract out in a teenager They could be really tricky to treat Vkc so these are usually we don't really see vkc a ton in Utah But the high association is with atopic dermatitis It usually gets better as they age But they like to ask about these shield ulcers. So these are usually superior in the cornea underneath the lid And then if you look for Cobblestone papillae on the upper eyelid kind of similar to GPC, but a little different appearance So I think this is why we don't see it as much because we don't have as many African-Americans in Utah Oh that also they like to ask about these horn or Trantas dots that you can get these are pretty extreme I've seen these a few times in patients where they're just kind of Pretty small right at the limb this like point two millimeters just tiny little dots that are kind of elevated 360 degrees around the limb this Vkc, but that's a pretty extreme case there of it Okay, so we talked about most of that so you get kind of the pathology has a bunch of mixed inflammatory cells with vkc and You try to treat these Systemically and topically with antihistamines mass cell stabilized combinations. So and then with vkc and akc I try to get them to an allergist Because I do think that desensitizing them with shots can help This is something that they do bring up occasionally when you have big papillae where pred acetate has some precipitates in it And so they don't really like you to use that because it can kind of get caught in between the ridges and cause more inflammation So dexamethasone is a little bit better drug for it superior limbic Caridoconjunctivitis kind of a tricky diagnosis to make in a lot of cases But what you're looking for is just sort of sectoral conjunctivitis of the upper conjunctiva underneath the eyelids Thyroid dysfunction and contact lens use is where you usually see this and it stains pretty good with rose bangal as you Can see here, but usually you can pick this up just by Pulling up their eyelids and having them look down you can kind of see it there It's common to have filamentary keratitis associated with this. It's usually redundant conge that's kind of gotten swollen and and enlarged over time and so the treatment for this is Usually just topical anti-inflammatories will get it, but not always and so sometimes I'll put them on cyclosporin Just treating essentially dry eye keep them really lubricated with restasis Sometimes 2% cyclosporin you can cauterize the bulvar conjunctiva to shorten it superiorly A lot of people go in and resect it and do amniotic membrane grafting to kind of help They like this don't use a silver nitrate stick on the eye it cauterizes sort of out of control It's usually pain pain and irritation for body sensation Similar to kind of lower eyelid conjunctival clases So recurrent erosions extremely common usually there's a history of a prior abrasion or trauma to the eye But also in EBMD you see a lot of this Generally they wake up with pain in the middle of the night or in the first thing in the morning When it's kind of when it comes on We're essentially treating these with antibiotics lubrication the contact lens and then potentially a cyclopenylator atropine If it's chronic use Muro to kind of help get the epithelium to sort of stick a little bit better And then there's surgical treatment stromal puncture I've done this a few times when it's not central, but you can't do this when it's central stromal puncture You're essentially puncturing through bowman's layer to try to create Scarring and adhesions and so if it's peripheral it's okay to do this But if it's central you can't really do it So generally I do a superficial care technique with diamond burr polishing So you're kind of polishing bowman's kind of roughing it up a little bit and to help the skin Seed in a little bit better. You can't do PTK, which is a laser-based essentially treatment to bowman's layer to help it stick as well Just a couple little things about viral That'll come up on tests. So when you have a hemorrhagic conjunctivitis Coxsackie is a common one and then EKC That'll come up EKC they'll sometimes ask you about the types of the virus and those are the the main ones that That cause it new castles disease. I've never seen it tested But it's kind of a unilack kind of this combination of things. They've got long issues plus those two usually in people who are dealing with chickens and Beloscombe is a very common test question. It's a pox virus in that chronic follicular conjunctivitis look for the lesion on the eyelid Okay, so chlamydia We we don't see it as much in The US, but this is a common issue worldwide. So it comes up on tests a lot So you get the Herbert's pits, which are kind of these almost like hollowed out areas on the limbis The Arlt's line is conjunctival scarring on the on the upper eyelids Kind of that white line right there These you'll see on Pathology so you get the intro side of intra cytoplasmic inclusions Yes, those are kind of the different ones that you'll see usually A through C on the eyes They're causing most of the issues Paranoid's disease Comes up occasionally usually lymph adenopathy granulomatous sort of follicles So you'll see kind of elevated lesions on the conjunctiva huge differential diagnosis biggest thing is cat scratch disease I don't know that I ever really saw this but this is something that potentially could come up Sporotricosis they like to ask that question on Step exams, but doesn't really come up on the eye much So those are just kind of all the things that can cause granulomatous disease on the eye Okay, so reactive arthritis they love this one can't see can't be can't climb a tree They like to ask you about what the rash is the keratoderma and blender adjuicum on the palms of the hands HLA B-27 associated disease usually so floppy eyelid syndrome really common diagnosis that I make in clinic It's usually not a lot of sort of elevated Inflammation, so you're usually not seeing follicles. It's usually kind of a papillary reaction The eyelids essentially just divert you pull on these lids you can see their lacrimal gland It's crazy when you see how much you can divert the lids Lower eyelids become kind of lax and away from the globe as well High association with sleep apnea, so get them tested for that Generally the treatment is just lubrication and then potentially taping their eyelids closed wearing moisture chambers But sometimes you can get Plastics to do a big wedge or section of the upper eyelid to kind of Treat and get rid of the floppy eyelid, but you got to do sleep apnea testing on them Pigmented lesions again, you've got the 14 year old kid who comes in with the growing lesion on the conch It's usually cystic in nature I still take these off because parents are freaked out and Melanoma is becoming a little bit more common of diagnosis even in young kids, so If it's if it's bothering parents, I'll take it off. There was I'll just watch it closely But the key is is that there's cis and there's increased melanin not increased melanocytes That's kind of a big differentiation between Pete Pam and just racial melanosis or conductival nearby So proliferation of intraperthalium melanocytes in Pam and usually no cis so with Pam You're kind of thinking a little bit more pathologic you're headed towards potentially developing melanoma So we're gonna watch these a little bit more closely and usually You're not seeing this in a teenager that's going through puberty. It's usually a 30 year old 40 year old that's having these Growing over time so pretty high risk of melanoma But a lot of times we'll just watch them closely and if we're seeing changes then excise them Okay, so malignant melanoma I never saw this but I was reading this on a On a test prep website to look at atypia on the path slide. You have to bleach the specimen I haven't heard of mammals doing this I guess I don't really see that many melanomas but a lot of times you get too much pigment in the lesion And so you can't tell what the cells are doing and so they'll kind of bleach out the pigment to be able to tell what the cells Look like to see how much atypia and things there are Again, this is becoming more common What you worry about is when you have a lesion that's elevated and you have sentinel vessels going to it Increased risk of beds if it's thick so two millimeters thick and then they'll ask about this A lot where it's it's worse if it's kind of in non sun-bearing areas or sun exposed areas So the eyelid margins kind of especially if you have a palpebral Conjunctival pigmented lesion that's a worrisome thing because the skin is not exposed to the sun very often there the car uncle as well Usually these will go to regional lymph nodes, but you've also got the other things that it'll head to kind of far away Not commonly Tested not commonly seen much, but gelatinous plaques This can be a benign thing Usually we would treat these or take them off because they look too much like cancer Oncocytoma they just love this one for some reason if you have a mass at the cart uncle think of oncocytoma There's a lot of mitochondria so you get eosinophilic cytoplasma in it. It's more common in women Corneal nerves so diseases where you get enlarged corneal nerves I never came up with a way to remember this I just tried to remember a couple of them Karate conus is an easy one to remember where they look a little bit more visible But actually enlarged bigger corneal nerves. These are the diseases that that's in Acanthamoeba the reason you usually see enlarged corneal nerves is because you get inflammation of them And so that's a common Thing that we're looking for and we're thinking of Acanthamoeba is perinuritis where the corneal nerves will actually enlarge a little bit ichthyosis autosomal dominant Nasty-looking skin get corneal opacities Get band carotopathy pretty early on in this. There's lots of syndromes that come up with it But it's it's an it's all about hydrating the skin the skin just isn't well hydrated because it's thick All right burns so corneal burns will come up a lot They'll ask you why a base is worse than an acid in in causing long-term damage, and it's because The alkali denatures the proteins but doesn't precipitate them when they get precipitated It almost acts as a barrier to prevent acid from penetrating deeper into the eye, and so historically alkali burns are worse They usually don't ask about this grading scheme But if you just think about when you've got a total epideffect Strummel haze and but it's not the whole limb miss here at type 3 and then you've got a larger amount of limb misses type 4 Those are kind of the biggest distinguishing points So you're gonna irrigate you're gonna debris These people should have a couple liters of saline flush through their eye before a pH has ever even checked And then you're gonna irrigate until the pH is normal Usually hit these people hard with steroids in the first few weeks and then kind of taper off quickly You're kind of battling epithelialization versus the inhibition of that with steroids and so but you have to knock down the inflammation first Usually treat with an antibiotic if there's an epithelial defect and cycloplegia to help You want to check pressure in these people be especially with alkali injuries because they can have very high pressure We usually put them all on doxycycline lots of lubrication Vitamin C is also helpful to Decrease collagen breakdown OCP a type 2 hypersensitivity you got the immune complexes of IgA They'll sometimes bring these up all these drugs that can cause sort of a chronic inflammatory scarring of the eyelids as well Usually you're gonna treat these patients with daps on on the test, but you have to watch out for g6pd or sulfa allergies We're starting to use more big gun medications like cell septin or tuximab And a lot of times that can keep the disease pretty quiet Other things to be thinking about with sigatricial conjunctivitis We do this to a lot of patients with glaucoma medications Bad infections that cause membranes and pseudo membranes so EKC can give this to you You could also get this with bad burns Autoimmune diseases that can bring it on and then obviously the trauma So we can do this to patients conch surgery get recurrent to regia that can sometimes scar up to the eyelids things like that, so Radiations another common one. All right, so interstitial keratitis syphilis is the most common cause of this When it's congenital syphilis you get the Hutchinson's triad with Teeth problems the cornea and then deafness, but also these are the other things we're thinking of Did I say syphilis was the most common sorry Herpes is the most common syphilis less common that happens if it's bilateral you're thinking syphilis Lots of sort of uncommon things that can cause it as well Cogan syndrome comes up occasionally on tests The biggest key is that they have hearing issues Tigason's not a very very fun disease to take care of Just little inflammatory nodules that come up on the cornea It's usually bilateral. They're kind of they'll kind of come and go regardless of what you do to them If you treat them sometimes they get better sometimes they don't if you don't treat them sometimes they get better sometimes They don't so they're kind of frustrating I usually try to get these patients on Rhystasis and treat their exacerbations with steroids steroids what they'll classically test on is that it will kind of delay that Sort of resolution of these long-term and it increases their chance of recurrence lead Honestly don't know what I guess it's a good question. Yeah, I'm not sure what what's in those little inflammatory spots These will have negative stain to them. So it'll kind of stain around the lesions at the base of them Usually no other inflammation. So their eyes are pretty quiet. They just have pain and photophobia I do yeah I try to get them on it immediately the first time I diagnose it and then you'll treat them with Low to max or bread to kind of calm it down help them I just do it just you just get rastasis Spheroidal degeneration there's lots of different names for this It's usually bilateral. It's not lipid. These are actually just weird protein deposits that come up. It's not really understood what this is Usually the patients don't notice this but if it becomes sort of visually significant you go remove these It looks like elastoid degeneration again, not a common thing. That's tested but Other things that are on the cornea that come up again that the limbo girdle of vote I see this a lot in patients who get this little clear space on the limits Then you'll have this little band of whitening That's usually not very elevated. It's kind of flat It's just collagen changes that are happening within the stroma the cornea. It's pretty anterior Hassel Henley bodies they like to ask about this. You'll see gutata in the peripheral cornea. That's non-central Those are just normal aging things. I Wish we could just forget about these the mucopolysaccharides, but they just keep testing us on them Even though I've never seen any of these in my life The cornea is clear in hunters and the skies are clear in San Filippo is the way to kind of try to Figure out that these do not have corneal disease with them Whereas the rest of them can't have corneal clouding So if you can memorize those two with clear corneas, that's usually all you need to know about those two Hunters is excellent hunters like to shoot the X So sphingo lipid OCs these are all autosomal recessive except that one fabrics. It's excellent recessive It's on the differential for world-care top of the verticillata And so the other things to think about are amiodarone chloroquine and then endomethacin and NSAIDs can do it as well Pretty common to see this on patients It's usually asymptomatic not causing a lot of issues. I It's hard to know for sure if it's causing dryness because I feel like everybody has dry eye So I usually just lubricate these patients and don't really recommend that they stop their medications. Yeah Really superficial So cystinosis Pretty rare disease, but we do have a couple families in Utah. So you'll you'll see these patients occasionally They usually do not have a change in vision, which is really surprising when these get really bad, but they're pretty photophobic They're usually short in nature. They have kidney problems. So they usually had kidney transplants. So Their eye problems are tricky to treat because of the treatment is Topical cystia mean every hour. So try to get a kid to take a drop every hour to help him reduce his corneal crystals It can cause band care top of the so you definitely want to treat these patients and encourage them to get their cysts under control So here's a patient that I saw a couple weeks ago in 2012 this is what his cornea look like and This is what it looked like last week So these crystals are in every layer of the cornea and it looks like fiberglass in the corneas Essentially and his vision was 2025 with correction And this doesn't do it justice. They're just everywhere in the cornea So cystia mean drops every hour both eyes Mainly to get rid of their photophobia prevent band care top If you did a PK on that patient had come back so Again, it's not usually visually significant Wilson's disease. We love these consults come rule out get a Kaiser Fleischer ring exam make sure that they don't have Wilson's disease But it comes up a lot on tests Usually that ring will go away if you treat it with penicillin mean sunflower cataract The Kaiser Fleischer ring is in decimase membrane. So that's kind of the key point for the test So band care top if you think about chronic inflammation multiply surgeries as causes of band care top of the These are elevated. They're usually cause irregular epithelium a Lot of times the reason we're treating these is because the epithelium is breaking down and so they're having pain and irritation So you do EDT aculation you can do this in clinic or you can do it in the OR I usually take them to the OR and then You can potentially do PTK to kind of help with the With the corneal opacities and it usually comes back It's kind of tricky unless you get the inflammation under control silicone oil in the eye is another high risk factor for this iron lines another dumb test question that they just love to ask you about They're pointless other than a Kaiser Fleischer ring Everything else doesn't really matter, but Stalker's lines at the Trigium the fairies line is by a bleve and you've got the Hudson stolly line That's normal in aging just at the where the lower lid tears kind of hang out on the inferior half of the cornea Other random deposits so Kruggenberg spindle is probably the most common one that you see you get melanin on the endothelium But argerosis can cause kind of a discoloration of the sclera where it looks a little bit blue and colored almost Almost does look silver. It's kind of a blue issue Okay, so marginal caratolysis or puK So these are some of the common common test questions that they love to Hammer you out on so it's usually unilateral and it's right at the limbis. So it's peripheral It's immune mediated where the collagen is actually melting. So you're getting actual thinning of the cornea It's associated with autoimmune diseases. So most commonly rheumatoid arthritis is is where we see it the most But you can get it in lots of different autoimmune problems A lot of times they'll have inflammation of the sclera sort of right next to it. So again autoimmune process Treatment we essentially you've got to immunosuppress these patients There's a there is some argument that topical steroids actually play a role In helping to control the local inflammation, but this is mostly systemic in nature that you're trying to treat As soon as the epithelium heals you're kind of out of the woods, but these can spontaneously perforate so kind of hard to Hard to treat in some cases Moran's ulcer usually painful progressive ulceration It usually does not have the sclera involvement the test question is hepatitis C association There's kind of a leading edge to it. That's kind of undermined and you've got kind of this overhanging cornea So it's almost like it's getting eroded underneath like water does to the side of a mountain Again immunosuppression you can resect the conch back recess it to kind of get the inflammatory factors away Not not as not as good with Puk, but it is a treatment that is used Terrians is usually younger patients The epithelium is intact. So there's usually not staining You've got this kind of lipid leading edge at the edge of blood vessels that are coming into the cornea They love to ask about the against the rule of stigmatism is what you're getting initially in the intact epithelium These are tricky because they can perforate with mild trauma. There's not great treatment for it You're just kind of lubricating these patients and hoping they don't send too much and it burns out Bugs that can in going through an intact cordia. I've never been able to memorize this either So I just try to remember a few of them and move on with my life gonorrhea is the one that I worry about the most but You can get carinobacterium as well. These other ones aren't as commonly tested Crystalline carotopathy can be anything. So on a test question It's most commonly strapped, but you can have any disease causa or any infection cause crystalline carotopathy You can even see it in steroid use So herpes simplex So these are intra nuclear compared to intra cytoplasmic inclusion bodies in chlamydia. So that's one of the test questions Usually multi-nucleated giant cells on gymsa or a zinc prep The heads trial honestly, I'm It didn't seem like this came up a lot on O caps, but these are kind of the points of the heads trial This just sort of breaks down all the different sort of groups that were tested So when you have stromal keratitis what they essentially did is they said okay, we're going to treat all these patients with topical steroids and local antivirals and then we're going to see if oral acyclovir matters in the first group and there was no added benefit To oral acyclovir when you're treating with local triflory in stromal keratitis Another group that they did was trifluridine with steroids versus trifluridine with nothing else And it looked like topical steroids actually did help So in stromal keratitis technically all you need is topical steroids with some sort of Antiviral either honestly either oral or local but in the studies It seemed like they were powered to help with the local treatment. And so that's what came out in the studies is that that was I don't know actually I've wondered about that you have to assume so So if if you have iridus from HSV Then they said okay, how about in this case do it does systemic acyclovir help? So you've got the topical steroids and trifluridine in both groups and then the placebo versus acyclovir There was a trend toward benefit, but not statistically significant. So we usually treat these with Orally acyclovir and I usually treat stromal keratitis with orally acyclovir to such a benign Medication if it's going to help HSV is a crappy disease What about somebody with epithelial keratitis? Does it prevent? Other problems if somebody comes in with dendritic keratitis if you give them Acyclovir does it help so most of these patients would historically be treated with topical trifluridine And there was no benefit in preventing Consequences of disease if you use systemics acyclovir Again, is this what's done in practice? No, but it's the good old heads trial HSE prophylaxis The dose is 400 milligrams twice a day versus placebo. It did reduce the risk of recurrence when you're prophylactic somebody It was but it worked better in stromal keratitis Okay risk factors hard to say for sure what the risk factors are This is what came out is that if you somebody has epithelial keratitis It doesn't increase their risk of recurrent epithelial disease But if you have stromal keratitis, it definitely increases your risk of recurrent stromal disease So you want to be a little bit more sort of long-term aggressive with your suppression when somebody has stromal keratitis versus epithelial keratitis That makes sense Zoster so nobody's gonna miss this zoster. This is a crappy zoster patient that we had at Moran It essentially destroyed the upper eyelid But they love to test about Hutchinson signs. So if you've got a lesion on the tip of the nose You're more concerned about ocular involvement. Primary care doctors use this a lot to get to determine whether or not to get an eye exam Topical antivirals are not useful in this. You're using a higher dose of acyclovir and then oral steroids I think most people use oral steroids when somebody has this bad of disease So another common test question dendrite versus pseudo dendrite HSV gives you dendrites pseudo dendrite comes with a BZV and The staining is what they'll ask you about the base stains well foreseen But the edges stain well throws bengal and this one just doesn't really stain with either one And you'll usually get scarring at the site of the dendrites the pseudo dendrites in BZV Fungal infections not as common here in the United States Some of the stuff that tends to come up is whether or not to use boriconazole Natomycin works really well for filamentous Fungus, but doesn't then boriconazole is not really that much of an added benefit in these situations. So Come to come to Farmington I have one it's loads of fun Because the only ones that I've seen Yeah, you asked for Jillis in Canada most commonly, but I have a fusarium ulcer I'm not kidding you like four months to heal the epithelium is brutal She had HSV and then developed a fungal ulcer like three weeks into it And was referred to me like I wouldn't know what's going on with this patient So we cultured it in fusarium crew. It was awesome Acanthamoeba again, not as common in Utah, but we see it occasionally We're usually using confocal and then cultures to try to diagnose this. They like this double walled cysts You just think about Acanthamoeba being a fortress. It's really hard to treat and kill Here we're using usually chlorhexene and phmb And then we'll sometimes ask the patient to get Broline from other state other countries You can get it from Canada and France pretty easily on Amazon Micro Spiridia, I don't know never seen it on a test You're thinking about HIV patients that have complications from this Okay, keratoconus they will ask lots of questions about keratoconus They'll show you all these signs that you have to know and I mean these are some of the easiest test questions to get when somebody is Is looking down and they say what's this What disease do they have sometimes that'll be a quick question You get flies through rings you get high drops You get the prominence of corneal nerves. This is the vertical Straye votes lines in the cornea Scissoring on retinoscopy Resudi sign is when you shine the light sort of temporally and it reflects and causes a shadow on the On the nasal or on the limbus High drops they'll ask you to do a pk in high drops weight Can inject air bubbles usually we just treat them with steroids and cycloplegia in given time Be surprised at what they can see you after a high drops episode So keratoglobis Usually doesn't have any real corneal findings So you're not seeing all those same things that you're seeing in In keratoconus but they can develop high drops and they can perforate Pretty easily but they're super steep corneas and really thin Not a lot of great treatments for this pks are kind of hard to do in this condition because the corneas are so thin Um, polluted is actually fairly rare. Um, usually the polluted patients that we diagnose or they probably just have a variant of keratoconus The key to polluted is sort of where the thinning is happening So with keratoconus the thinning happens at the apex of the cornea and polluted the thinning is happening Just above the thinnest area Is where it kind of sticks out. So this is kind of a diagram of it So you do classically get that crab claw appearance, but these can actually be keratoconus patients too that have that appearance So you've got the protrusion just above the thin area Another just distinction keratoconus Versus polluted kind of that sagging cornea Okay, so corneal dystrophies. Um, I think this gets hammered into you pretty good my mamless Yeah Uh, yeah, you can't get a months in sign. It's not as prominent because the the thinning is so low Um in the cornea that when you look down It doesn't have that exact same sort of effect on the lid. We have a couple of really good Pollucid pictures in axis. I should have pulled those in of patients that we that we have here Usually don't get a perfect months in sign, but it can't cause some of that distortion down low um, so I'm actually going to just Brush through these because I think these are Ones that you get pretty good with mamless But anterior basement membrane dystrophy is really common Um, very under diagnosed It's usually bilateral. You're going to see little dots or cysts sort of in the epithelium, but usually you'll just see kind of irregular lines Um, lots of erosions 10% giddy erosions, but 50% with erosions have ebmd. It's another one of those common things they like to ask about Miesmann's is autosomal dominant not very common. Um You can't have some corneal thinning and decreased corneal sensation. These cysts stain with pas It's this peculiar substance That no one's been able to come up with a better term for Usually pretty minimal symptoms and usually don't have to treat these patients, but they can get erosions as well And so you're usually lubricating and and sometimes treating that that part of it Good old gelatinous drop like dystrophy autosomal recessive These are usually causing problems for the patient But are really tough to treat because pks don't really work reese booklers another autosomal dominant one Um This is kind of the pathology key that they'll ask about where you don't have bowman's And it's just kind of this connective tissue that's not as regular as bowman's is You get kind of irregular epithelium that stains within the sun trichrome as well Another one they like to ask recurrence rates in pks So you've got lattice granular macular and reese booklers has the highest rate of recurrence in a pk Uh, another one you don't see very often curly fibers on e.m Occasionally tested What's that Yeah, yeah, how you gonna diagnose that Send their cornea for e.m. I haven't done that before You've got this memorized. So that's an important one to keep straight Macular granular lattice. There's not really much to add to Mammalus's lectures just kind of go through those Again, the recurrence risk in a pk Avalinos, it's kind of a combination of granular and lattice. It's also on the autosomal dominant They do like to ask about the tgf beta one dystrophies Um erosions happen And they'll same with both granular and lattice so the same both of those Um Sniders comes up you got 50% that are kind of these yellow white crystals Sort of right outside at the limbis. They don't extend all the way to the limbis. There's kind of a clear space there But these are kind of deep. They're just below bowman's layered Um, sometimes they'll ask about this where they can see a little bit better at night There is association with the lipid problems stains with oil reto So there's kind of things to think about when it's lipid That comes up occasionally. So fleck dystrophy I've probably missed this. I don't know never seen it. There's such tiny little changes that it's kind of hard to hard to diagnose but Um, there's lots of associations with it And it's kind of glycosamunoglycans and lipid deposits Uh, we do kind of see this a lot Looks kind of like crocodile chagrin. It's pretty common. It doesn't really cause a lot of issues, but you'll see this in VA patients Fuchs dystrophy commonly tested Make sure you know what fuchs is Gutata they'll show the path slide just like this to be able to diagnose it pretty easy Um, it's not just reduced endothelial cells But you have to think about those endothelial cells as they die off the other ones around them get bigger And so that's another way to diagnosis with a lot of Sort of polymegethism and then pleomorphism of them. It clusters in family, but not perfectly genetic But you can diagnose these people pretty young They usually don't come in complaining, but you can see it in their 40s Um, the timing of treatment Really depends on morning symptoms. A lot of times that's when they're According is on taking on the highest stress. So d second d mech are kind of the treatment now But you can hold these people off with muro and just lubrication to try to Prevent some of that swelling that's happening. But usually if they're symptomatic we're headed into surgery PPMD actually pretty commonly seen too. I see these in a lot of screening patients for refractive surgery You're essentially just getting thickening of the endothelium And so you'll see just little areas right on the endothelium that are kind of heat up Usually doesn't cause a lot of issues, but it can be pretty pretty impressive and cause problems Uh, I don't know what that is Craft rejection You got to watch out for these battle lines and kuduhus lines. We have a patient of VA right now That has a pretty good one of these that's kind of marching across destroying his endothelium You'll see it regress back as it improves. It usually leaves kind of fibrosis and damage So a sign of endothelial rejection Um, I think so I think it is just kb, but I don't know for sure Yeah, we were able to reverse it. I mean it was like it two-thirds and now it's like it one-third last time we saw him But he has a really bad cataract. So who knows how he's doing? Yeah, you still hand motion um ocular melanocytosis Um, the key here is to think about melanoma risk glaucoma risk Um, usually just taking photos and watching these people really closely get ultrasounds with harry to look for nevi in that in the coroid Lignis conjunctivitis Really tough I've never seen one of these but sounds like it's really really hard to treat. It's a type one Plasmidogen deficiency Um, this is kind of interesting So before you take these people to or you have to watch out because they can have respiratory tract involvement And can cause really difficult issues with anesthesia. So that'll come up sometimes on tests But these are kind of yellow elevated really rough looking lesions of the lids Kawasaki's disease um young kids The reason that this comes up is because you'll get bilateral conjunctivitis and a majority of them then you can have uvitis as well so you'll See that they love to ask about the systemic treatment. Don't treat with steroids You have to treat with aspirin and IVIG Because of that risk of coronary artery aneurysm. So they'll ask What test should you get in this patient? You just diagnosed with Kawasaki's disease and It's it's an echocardiogram to look for those Uh, big fronts of the eyes Those are the associations high myopia You'll see this in cataract surgery The front of the eye is just massive in high myopes, but also some other diseases um Staphylomas I don't know that I ever saw this asked but decimates is absent It's kind of the key to this And you'll get it's it's essentially an anterior Dysgenesis syndrome where you'll have all kinds of weird connections A cornea plane is a really flat cornea. So you can see here. It's just ridiculously flat usually in the 30s Um, I've had somebody I've seen somebody with a native cornea that was like 36, but I've never seen anybody below that Lots of weird things that can happen to them, but really shallow anterior chambers as you can imagine without that vault of the cornea Sclerocornia, we have quite a few patients with this that we've been dealing with Um, you essentially have that type 1 collagen that just keeps going into the cornea irregular And so it ends up opacified. Um, usually bilateral it usually does not progress But really hard to treat these need a pk if they're If you're going to get any vision out of them early on Uh megalocornia, so big corneas horizontal diameter greater than 12 at a newborn 13 in an adult So common numbers that they'll test you on normal axial length Compared to boobop thalamus where the whole eye is large So that's the differentiating feature X-linked usually male that have it And some of the associations Um Micro cornea so less than nine in a newborn less than 10 in an adult And they're usually pretty flat corneas Peter's anomaly so again an anterior segment dysgenesis syndrome where decimates and endothelium Are not appropriately formed and so you have connections with the lens and iris lots of glaucoma Uh, usually bilateral You got pack six mutations. You have to think about in here So other pack six mutations axon filled Riger Peter's anomaly and then aniridia And they'll love these questions where aniridia is sporadic versus familial and which ones have the higher risk of the Wilms tumor sporadic Okay, decimates tears. Um, so vertical usually forceps trauma or Um, you get vote striae Where you'll see little lines in the cornean keratoconus horizontal think hob striae and congenital glaucoma Luckily, we don't see as many forceps injuries, but they still happen I have like a 50 year old who had bilateral forceps injuries when she was younger Um, I'm pretty sure is that lins patient. I think we did a desec on her It's kind of interesting Because her her cornea was kind of chronically cloudy and she did better It's kind of weird Uh ched so endothelial dystrophy in ched So because of that it's usually um an ademinis cloudy cornea Whereas congenital stromal dystrophy is just a thickened cornea But usually not ademinis So that's the key differentiating feature Um, you've got the autosomal dominant autosomal recessive that they'll sometimes ask you about Where there's a little bit of a difference to it So stromal dystrophy not progressive But these are no corneal edema because the the actual endothelium is functioning fine They say normal pochimetry, but they're usually thick They're still thick corneas, but they're just not cloudy corneas Uh, we only have a minute congenital cloudy corneas you guys memorize this Think about it when they show you a cloudy cornea in a kid One of the hardest things on ocaps is like coming up with a differential diagnosis Um, and so kind of try to step back for just a second and think okay. What else could this be? Because I'll try to trick you on some of these, but so that's a good one to always remember Um riley day syndrome This is kind of the thing. They don't want you to kill patients. It'll come up occasionally But they have decreased uh, corneal sensation and they'll end up with neurotrophic keratitis What's that? Yeah, exactly Um aniridia we talked a little bit about this But again, it's a pack six mutation and you have to watch out for the Wilms tumor in the sporadic kind There's lots of other things that come with it. So they're usually not seeing well along with the stem cell deficiency Which is the thing that we battle the most Ectopia lentis those are the things that cause it you got marfans Homo cystinuria wheel marshal shani In these patients their lens can is usually kind of a little bit on the small side Um ailer stanlos connective tissue disease again that causes lots of loosening of everything Uh genetic cataract associations Um this is a pretty High yield slide with all this all these things that they love to ask about Myotonic dystrophy comes up a lot with Christmas trees And to your lenticonus with alport syndrome mature cataracts and hollerman strife The oil droplet cataract they love this one with galactosemia that goes away. You don't treat it You don't take it out. You just treat the galactosemia and it can reverse And then your ice syndromes are another common test question that they like to ask about you got kogan reese Chandlers and essential iris atrophy with difference in the iris component Whereas you'll still have some of the other malformations in all of them cool Way too much info Lots of info in cornea problems, but it's easy to take pictures of so they like to test it