CORNEAL DISEASE
There are a wide range of diseases that can affect the cornea, which is the front clear dome of the eye. The cornea is normally clear and helps focus light into the eye, working like the front lens of a camera. However, certain conditions such as Fuch’s dystrophy or keratoconus can cause decreased corneal clarity due to swelling or abnormal corneal shape, respectively, leading to diminished vision. Treatment of corneal disease depends on the severity of symptoms. In many mild cases of corneal swelling, treatment consists of therapeutic eye drop medications or observation alone. In more significant cases a corneal transplant can restore the cornea to its natural clarity to improve vision. Please click on the link below or to the right to learn more about corneal transplants.
Certain other conditions such as epithelial basement membrane dystrophy (EBMD) or poorly healed trauma can lead to breakdowns of the corneal surface, leading to painful erosions or even infections. These can also be treated with topical medications and lubricants when mild, but refractory cases may require a procedure to improve the adhearence of the surface cells to the underlying corneal stroma, reducing the chance of developing another erosion.
KERATOCONUS
Keratoconus is a condition in which the normally round, dome-like cornea (the clear front window of the eye) becomes thin and develops a cone-like bulge. Keratoconus literally means “cone-shaped cornea.” The cornea is a very important part of your eye. Light enters the eye through the cornea, which refracts, or focuses the light rays so that you can see clearly. With keratoconus, the shape of the cornea is altered, distorting your vision. Keratoconus can make some activities difficult, such as driving, typing on a computer, watching television or reading.
The treatment of keratoconus depends on the severity of the condition. In mild cases, patients with keratoconus may still achieve good visual acuity with glasses or soft contact lenses. As the disease progresses and the cornea becomes more abnormally shaped, rigid gas permeable or hybrid contact lenses may be prescribed. If the disease progresses still there are surgical treatments available including INTACS ring segments, which can restore a more normal shape to the cornea, collagen crosslinking, which can strengthen the cornea to slow or in some cases reverse progression, and ultimately corneal transplantation, where a healthy donor cornea is used to replace the distorted or scarred one if necessary.
FUCH’S DYSTROPHY
Fuchs’ dystrophy is a disease affecting the innermost part of the cornea, the clear, round dome covering the eye’s iris and pupil. By helping to focus light as it enters the eye, the cornea plays an important role in vision.
Fuchs’ dystrophy is a commonly genetically inherited condition that affects females more frequently than males. It is a slowly progressive disease that slowly reduces the number of specialized cells (called endothelial cells) that make up the inner layer of the cornea. Endothelial cells are key to processing water that makes up the corneal cell structure. When the endothelial cells diminish, the cells stop processing water properly and fluid starts to build up inside the cornea. The corneal tissue gradually thickens, causing the cornea to become swollen and cloudy, losing its crystal-clear transparency.
Also seen in Fuchs’ dystrophy, are microscopic dewdrop-shaped outgrowths called guttae in the layer just underneath the endothelial cell layer (called Descemet’s membrane). These can also affect vision and cause glare and blurred vision. As Fuchs’ dystrophy progresses over time, changes to the corneal cells may interfere with vision. The condition can result in fluctuating vision, glare, halos and ultimately blindness in some cases.
The treatment depends on the severity of the condition. In mild cases no treatment is necessary, but as swelling worsens, some patients achieve symptomatic relief with high concentration saline eyedrops and ointments. In more severe cases a partial corneal transplant (DSAEK) can improve eyesight by replacing the diseased endothelial cells with healthy ones from a donor.