The cornea is the transparent part of the eye that covers the front portion of the eye. It covers the pupil (the opening at the center of the eye), iris (the colored part of the eye), and anterior chamber (the fluid-filled inside of the eye). The cornea's main function is to refract, or bend, light. This is a quiz about Cornea for all Opticians.
Hassal-Henle bodies (Descemet's warts)
Coat White ring
The deeper that a cut or injury goes into the epithelium, the longer it takes to heal.
Map dot fingerprint dystrophy or anterior basement membrane dystrophy that we will talk about that has weakened epithelium. Its about this type of condition that the epithelium does adhere very well and it sloughs off and leads to corneal erosion.
The stroma is the pump that keeps the cornea clear, the less stroma you have the less ability you have to control hydration
If you traumatize bowman’s, that’s when you develop scarring.Cells cannot regenerate so damage causes scarring
Bowman’s membrane, it is a tough piece of tissue, very difficult to perforate
Limbal Girdle of Vogt
Calcific Band Keratopathy
Terrien's marginal degeneration (gutter degeneration)
Conjunctival flap resection
Pulse - steroid pulse
Salzmann's nodular degeneration
No treatment is necessary in this condition
Had a couple of types, the anterior and posterior type. The anterior type is where you have the central corneal shows these polygonal pattern of grayish white opacities separated by bowman’s and the epithelium. The posterior type looks like it’s in the deep stroma and descemets region. Really its not causing any functional problem. The treatment and management is none.
Is a yellowish/white cholesterol rings in the peripheral cornea, lipids at the termination of Bowman’s. You’re going to be noticing this sort of whitish rings, some of them are very subtle and some of them very dense going around the cornea
Leads to a differential diagnoses of corneal guttata. When you have corneal guttata, it affects the endothelium,. So now when you have farinata, you have these grayish white flecks in the deep corneal stroma.
Could be from mechanical injury like forceps injury at birth, or could it be from increased IOP called congential glaucoma If the pressure is so high its pushing on the endothelium, so it’s going to cause problems to the endothelium and descemet’s
It increases the likelihood of a pterygium or a pinguecula forming in that area
The cornea starts to shrink in that region, the tissue doesn’t have its normal integrity like it used to. Then, over time what happens is that area becomes depressed and the tear film collects and a lot of stagnant tear film and a lot of bacteria may start to harbor in that area. So you run a higher chance of infection to occur because you don’t have good flushing of tears in that area.
That area will become non-responsive to attempts to hydrate it
It is a progressive non-inflammatory thinning of the cornea.
Calcific Band Keratopathy
Terrien’s Marginal Degeneration
Symptoms include decreased vision due to edema, usually worse in the morning, decreased VA may also be due to scarring.
It is an apical thinning of the cornea typically inferior and nasal to the visual axis which is bilateral, it results from the fragmentation of Bowman's membrane.
The pain may experience pain associated with ruptured bullae and epithelial loss.
Treatments include 5% NaCl 4-6 times per day and ointment at night, banadge contact lens as well as use od a hair dryer at arm's lengthe 5-10 minutes upon awakening.
Late signs include Fleischer's ring, the deposition of iron in basal epithelium around the base of the cone.
Acute hydrops can occur which is the ruptured Descemet's membrane leading to corneal edema usually resolving in 8-10 weeks.
Thinning of corneal stroma will be visible via biomicroscopy
Corneal topography will show areas of flattening, however there will be no distortions of the retinoscope reflex
Munsons sign manifests
Phlyctenulosis is an immune response from Staph exotoxins
Often Salzmann’s nodular degeneration comes from phlyctenulosis
It is the most common type of epithelial dystrophy
In Salzmann’s nodular degeneration, if the patient does have symptomology becaue it’s interfering with vision that’s when you think about removing them. You use the excimer laser to ablate it. if it’s way off to the side close to the limbus then you’re just going to leave it and watch those conditions.
Ask the patient if they had some type of red eye or eye infection in the past to help you with your current diagnosis. They say a couple years ago I had an eye infection and they gave me some antibiotics, or eye medication to help get rid of the problem. That helps you with your diagnosis because now you’re thinking maybe the patient had phlyctenulosis in the past and what we’re seeing is salzmann’s nodular degeneration.
Here's an interesting quiz for you.