The cornea serves the eye by shielding it from germs and debris, such as dust, in a function it shares with the eyelids, eye socket, tears and sclera. The cornea, which also helps bring vision into focus, functions as the outer lens and screens the eye from damaging ultraviolet (UV) wavelengths from sunlight. The best comparison is that of a window letting in light or a camera taking a photo.
That light is refracted by the cornea onto the lens, where the light reaches the retina. The retina signals the brain, which will identify the images. If the cornea can’t perform properly, the result is blurry images.
Fuchs’ dystrophy, a progressive corneal disease, reduces the number of endothelial cells, which are needed to process water in the eye. The result is a buildup of fluid, gradual thickening of the cornea and interference of vision.
The degenerative changes, which can include scar tissue that must be removed surgically, can lead to blindness and painful blisters, which also may need to be excised.
Fuchs’ dystrophy is primarily a hereditary disease that occurs in a patient’s 50s or 60s, though there are cases of development earlier in adults. Symptoms worsen over time and can include pain, sensitivity to light, night vision problems and foggy vision.
Early detection helps with treatment plans, and eye drops can help slow the progression of the disease. A corneal transplant also may be needed in late stages of Fuchs’ dystrophy.
Descemet’s membrane endothelial keratoplasty (DMEK) replaces the patient’s corneal membrane and endothelium layers of the cornea with donor graft tissue. The small amount of graft tissue needed for the procedure means lower risk of rejection of donor tissue, shorter recovery time and less reliance on long-term steroids.
Descemet’s stripping endothelial keratoplasty (DSEK) replaces the small layer of the cornea with donor endothelial cells. The procedure involves small incisions of the cornea and the removal of the endothelium. The donor cells affix themselves to the cornea. Recovery time is short, and the cornea can function normally within days.
Penetrating keratoplasty (PKP) is known as a full thickness corneal transplant. A circular piece of corneal tissue is removed and replaced with donor tissue. This procedure will significantly improve vision with a lengthy recovery time and medications to stop rejection of donor tissue. After recovery, LASIK surgery may be an option to improve vision even more.