 I'm going to go ahead and get started. So we're talking about congenital anomalies of the cornea, sclera, and globes. This is a pretty quick lecture. We'll just kind of go over a bunch of conditions here. Stop me anytime. But first, I'm going to do a little outline or a little kind of introduction to kind of the embryonal origins of the anterior segment. So the cornea and the sclera do come from a few different, I guess, embryonal tissues. The surface ectoderm is responsible for the corneal epithelium. Most of the corneal and sclera does come from the neural crest, which is going to give rise to corneal stroma and edithelium. Pretty much all of the sclera and also the iris. The mesoderm, however, does contribute to a small area of sclera temporarily. So with neural crest cell migration, there are three main waves that come in early on. So wave one occurs at week four, where the neural crest migrate centrally to form the corneal endothelium and the stroma. Wave two comes at week seven, where the cells start to invade the corneal stroma. And then they also will condense as sclera and migrate posteriorly. And the third wave at week eight, the neural crest advances to form iris stroma. Later on, by the third month, the corneal endothelium bends down to one layer. By the 12th week, the eyelid folds meet and fuse. And then the congenitiva and the corneal epithelium start to develop away from the amniotic fluid once the eyelid folds have formed. And decimates membrane becomes a continuous structure. By the fourth month, the keratocytes within the stroma align and collagen amela are laid down. So there are many causes of congenital corneal anomalies starting with intrinsic factors, genetic factors. There can be impaired cellular induction and proliferation, defective cell migration, abnormal cell death, abnormal extracellular substrates, inadequate differentiation, as well as physical constraints. Extransically, there are also factors such as maternal health and external teratogens such as radiation, the torch infections, and medications. So we'll go through a bunch of conditions here. So cryptophthalmos is a condition where there's actually no eyelid slashes or eyebrows, and the cornea is fused with epidermis. There may or may not be an interchamber, iris, or lens. And this can be unilateral or bilateral. Microphthalmos is perhaps a bit more common. This refers to a small, malformed globe. And there can be an associated cyst or cystic outpouching. And microphthalmos occurs when there is associated with a failure of fetal fissure to close properly. Collabomidus defects are common. There are other ocular associations that are usually present, including persistent fetal vasculature. And there are a variety of causes for microphthalmos. It can be autosimilodominate. It can be recessive. It can be associated with other systemic syndromes. It can occur with torch infections. So there are a multitude of causes there. This is a patient I saw who was an inpatient who had, we didn't do an ultrasound to confirm whether or not it was kind of no right eye versus a kind of a microphthalmic eye. We were treating him for this left eye, which had a very, very shallow orbit, severe exposure. He wasn't able to close his lid at all. And as you can tell, he's got severe hydrocephalus, severe cleft deformities. Or his mother was told that he wasn't going to live more than a few days. So we were just going to temporize him. We put an advantage contact lens. He kept living. So then we put in a inpatient sclerocontact lens while he was in-house. So he's the youngest patient I've used the sclerocontact lenses on, and he did great. He kept living. He actually got discharged. Mom was putting in a bandage contact lens every so often. And I think he lived at least 18 months before he, I don't know what happened to him. He decided his mom wanted to take him elsewhere for care. So next we'll talk about nanophthalmos. So as opposed to microphthalmos, which is a small, malformed globe, this is a small, relatively normal eye. And there's usually very high hyperopia because of a short axial length. Usually that axial length is about 15 to 20 millimeters, normal axial length around 23, 24 millimeters. There is a very thickened sclera. And the bend's volume is higher than it is in a normal eye. And so that can result in anterior segment crowding, angle closure, glaucoma. Because there is thickened sclera, that thickened sclera can often kind of impede the venous outflow through the vortex veins during cataract surgery. So you do have to watch for a choroidal effusions or choroidal hemorrhage during cataract surgery. And one can consider prophylactic sclerotomies. A blue sclera is kind of almost the opposite as far as sclera goes. This uvia being seen through a diffusely thin sclera. This is seen in osteogenesis imperfecta type one, which is an autosomal dominant condition, which is associated with bone fragility, also associated with Ehlers-Danlos type six, which is autosomal recessive. And it's associated with joint hyperextensibility and cardiac issues, as well as other systemic issues. But this is not something that we typically treat, just something that's noted. Not nothing that's progressive. Microcornia is a condition where the cornea is less than 10 millimeters. But it is clear, it's got a normal picimetry. It is relatively flat, however, so that gives people usually a hypoeropic correction. And because it's relatively flat, it's also, there may be a higher risk of angle closure with more shallow anterior chamber. It's associated with other anomalies such as persistent fetal vasculature, congenital cataracts, anterior segment dysgenesis, and optic nerve hypoplasia. And there are a variety of conditions that can lead to a micro cornea, including myotonic dystrophy, fetal alcohol syndrome, and Ehlers-Danlos. As opposed to megalocornia, so megalocornia is X-linked. The diameter in megalocornia is greater than 13 millimeters. There are very steep K-values, and you can tell it's a very large, very steep cornea. It's histologically normal. This is not a progressive enlargement. One does need to distinguish megalocornia from congenital glaucoma, especially in a young patient. So, checking IOP would be the distinguishing factor. Also, with megalocornia, it is relatively clear, so you don't get the corneal clouding that you sometimes see with congenital glaucoma. It's megalocornia is associated with meiosis, iostroma, atrophy, cataract, and glaucoma. And it's associated with Down syndrome, Marfan syndrome, corneal synastosis, mental retardation, and osteogenesis imperfecta. Corneal plana is a very unusual condition. This is a very, very flat cornea, and there's no kind of area that you can point to that is the limbis. The corneal curvature is about the same as the adjacent sclera. And this condition occurs when the second wave of neurocrest migration fails to form the limbal angle. The case may be 20 to 30 diopter, normal keratometry values are about 42 to 45, so very, very flat. Patients may have angle closure, glaucoma, or even open-angle glaucoma, and it's seen with other anomalies such as sclerocornia, which I'm gonna go into next, and microcornia, and there can be associated cataracts, cobalmas, is also seen in Ehlers-Danlos syndrome. Sclerocornia is a non-progressive, non-inflammatory scleralization of the cornea, it's congenital. It's associated with cornea plana in 80% of cases, and there's basically no clear cornea, or very, very little clear cornea, and very, very abnormal angle structures. Exanfel regor syndrome, this is more common. This is a spectrum of anterior segment dysgenesis. I think the teaching now, we kind of used to teach all the different kind of syndromes within this spectrum, but now we kind of talk about the whole spectrum as one. This is usually autosomal dominant. There's always an anteriorly displaced traubies line, also known as posterior embryotoxin. There can be attached iris strands to the anteriorly displaced traubies line, as well as iris, hypoplasia, and glaucoma, in 50% of patients. So here are a few pictures. So this is showing kind of anterior displaced traubies line. It's white right here. This is showing iris strands that are attached to anteriorly displaced traubies line. This is another picture showing some iris strands coming up. And again, this is the anteriorly displaced traubies line here, this white line. So if you notice, you'll see this in a lot of patients who may not have any issues whatsoever. They're just coming for a routine exam. You'll see this sometimes, and I don't even note it anymore, but if you look for it in enough patients, you'll start to see this fairly often. And then this is a gonoscopic view showing these iris strands coming up to traubies line up there. Peter's anomaly is a congenital central corneal opacity with iris cornea touch. It is bilateral 60% of the time. It is mostly sporadic due to mutations on the PAC-6 gene. And there may be cornea lens touch underneath the corneal opacity, and it's highly associated with glaucoma and also aniridia. And this is a kind of a pathological specimen showing very thickened cornea. This is the lens where the lens was touching the cornea. And there's no endothelium and decimase beneath the corneal opacity that's here. So you'll have kind of a thickened cornea, but there's no endothelium and decimase down here. Whereas posterior keratoconus, which is an indentation of the posterior cornea seen here without protrusion of the anterior surface, there can be some overlying stromal haze right here. It's usually unilateral, it's non-progressive, it's sporadic. And in this case, endothelium and decimase membrane are present and underneath the stromal opacity. Congenital hereditary stromal dystrophy is a very, very rare. It is a dominant condition where there are bilateral flaky anterior stromal clouding with a clear periphery. It may be a little hard to see here, but there's a clear rim right here. There's no edema, photophobia or tearing. Posterior polymorphous corneal dystrophy seen a little more often. It's still quite rare. It's also autosomal dominant and it is always bilateral. And you'll see gray, white, kind of sheet-like stromal opacities posteriorly, so the posterior stroma. And you see more of it in the central cornea, but it does extend out to the limbis. On the slip-lamp photo here, kind of see a little kind of opacity posteriorly. Patients have thinner corneas, flatter corneas, but the vision is usually good. Most patients with this condition will have good vision and won't even know they have it. Ched, congenital hereditary endothelial dystrophy. This is a bilateral congenital corneal edema and there's two main types, ched one and ched two. So ched one is autosomal dominant. It comes up at age one to two years. It's slowly progressive. It's associated with pain, photophobia and tearing and there's no nystagmus. As opposed to ched two, which is autosomal recessive and most autosomal or recessive conditions just in general are gonna be a lot worse than autosomal dominant conditions. So we think along those lines, autosomal recessive is actually gonna be present at birth. It's not progressive, but there is nystagmus present and there's no tearing and photophobia, which you'll see in ched one. Congenital glaucoma presents at birth or within the first few years of life. There's a classic triad of tearing, photophobia and bluffarospasm. And then buphthalmus is the term that's used exclusively for congenital glaucoma, where there's a corneal diameter of greater than 10 millimeters. Corneal edema is seen in 25% of patients at birth and greater than 60% by six months. Classically, you'll see hobstriae, which are breaks and decimates membrane that are usually horizontal. This was a picture of bilateral congenital glaucoma, you see corneal clouding and edema. And then these are hobstriae, which are horizontal and this is what it looks like under retro illumination. Birth trauma can look similar as opposed with regards to the striae. So birth trauma, you'll see progressive corneal edema during the first few days of life. And you'll see typically vertical or oblique striae rather than horizontal striae. And edema may clear later, but it can recur later in life. So here are some pictures of birth trauma. This is some diffuse edema. I'm not sure if this is the same patient or not, but you can see some kind of oblique vertical striae here, some more vertical striae here, and then here's some that are seeing our retro illumination. Interstitial keratitis, this develops in the first decade of life and leads to a rapidly progressive corneal edema followed by a deep neovascularization. And the cornea may actually become pink. And this is a salmon patch of the cornea. And then once the neovascularization kind of fades away, ghost vessels are left behind in the stroma, which you can see here. So these are not, there's no blood really going through there and they're just kind of the ghost vessels. Ideologies of interstitial keratitis, most common being HSV and congenital syphilis. However, there are other rarer conditions you need to think about, such as Lyme disease, TB, Zoster and Kogan syndrome, which you'll see, which is by autoimmune condition, which is associated with vestibulo auditory deficits. I talked about congenital corneal cheloids a couple of weeks ago in the lecture. This is a typically bilateral condition. You'll see it in low syndrome, which is oculosuriborino syndrome with thick collagenase bundles. And it may look something like this, like a, almost like a pseudo-terrigium, but it doesn't necessarily have to have all this vasculature earlier on. It can look like a salzmin nodule. Congenital corneal anesthesia. So patients with this will have bilateral painless corneal opacities and ulcerations. And the anesthesia could be limited just to the cornea, or there can also be anesthesia of other tissues that are inner rated by the trigeminal nerve. So this is just, I mean, this is gonna be the ultimate neurotrophic keratitis. So got to treat very aggressively with lubrication, lip taping, might consider lateral torsorphy. This is a young child who probably has not just corneal, bilateral corneal anesthesia, but probably anesthesia of other facial structures, because there's a lot of injuries to the face. He or she's wearing a helmet, so they're not able to feel pain, so they're more likely to hurt themselves. Icyndrome is iridocorneal endothelial syndrome. And this, there's kind of a lot of unknowns regarding this syndrome. It might be congenital, which is why I threw it in this talk. But it doesn't become apparent until middle age. The genetics are unknown. It's usually female. It's pretty much always unilateral. And what happens is the endothelial cells of the cornea start to act like epithelial cells. So epithelial cells like to proliferate and kind of form sheets. And so the endothelium starts to do that. And as you can imagine, these abnormal cells start to proliferate. They can grow into the angle, onto the iris, producing iris abnormalities and glaucoma. And these abnormal cells can actually, because they're not acting like normal corneal endothelium, they're gonna lead to malfunction of the endothelial cells producing corneal edema. You can treat this with endothelial caretoplasty or PK. The glaucoma can be difficult to treat. And with either glaucoma surgery or corneal surgery, it can recur because you're not gonna be getting rid of all of the abnormal endothelial cells. There's always gonna be something that's leftover. So these cells can start to clog up trapecolectomies, clog up tube shunts. It can still recur in a PK or a D-seq. And I don't know if the books still go over the three subclassifications of an is syndrome or not. I thought the books were going to go away from that. But in the event that you still need to know the three subcategories, there's a nice kind of built in mnemonic for these syndromes. So ICEI stands for Iris Nevis Syndrome, which is seen here. See these tiny little bumps on the iris, which look like mevi. They're not really mevi. This is happening because of kind of contracture of these cells over the surface of the iris. Chandler syndrome. You see corneal edema as being the main issue here. E stands for essential iris atrophy, where you see atrophic thinning and even holes in the iris. So that's ICE syndrome. I think that's it for my talk. It's really short. We can go over other conditions or other questions on anything you've seen. You'll see a lot of congenital things and obviously on peeds. So I don't know if anyone wanted to bring up any cases or issues, patients they've seen. Okay, well, that's it.