Cornea Research Foundation of America: Fuchs' dystrophy and DMEK

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The Cornea Research Foundation of America was founded as a non-profit organization in 1988 by Francis W. Price, Jr., MD with a mission to give people back the use of their eyes.

Fuchs’ Dystrophy and DMEK

Today, through countless research studies and in partnership with Price Vision Group and its skilled surgeons, we’re making that mission a reality.

Francis W. Price, Jr., MD An internationally recognized ophthalmic surgeon, named one of the top physicians in the country for corneal disease and transplantation by The Best Doctors in America. Yuri McKee, MD A Board Certified Ophthalmic Surgeon with fellowship training in corneal transplant surgery from the renowned Emory Eye Center. Dr. McKee focuses his practice on complex surgeries of the cornea, iris and lens. Matthew T. Feng, MD A magna cum laude graduate of Harvard who was a Dean’s Merit Scholar at the University of Pittsburgh School of Medicine and also a Presidential Scholar representing Pennsylvania.


Cornea Research Foundation of America 9002 N. Meridian St., Suite 212 Indianapolis, IN 46260

Meet Price Vision Group Surgeons:

An explanation of the condition and your treatment options

Fuchs’ dystrophy and Treatment Fuchs’ endothelial corneal dystrophy (Fuchs’) is a hereditary eye disease with symptoms that often become noticeable after the age of 50. Ultimately, it causes loss in vision which can be treated with a cornea transplant. To understand Fuchs’ you must first understand how the cornea works, since Fuchs’ initially only affects one single layer of the cornea. The cornea is the clear window on the front of the eye and is comprised of three main layers—the epithelium, stroma and endothelium.



These two images show endothelial cells, the cells that make up the endothelium layer of the cornea. The image on the left depicts a healthy endothelium where hexagonal cells are clearly outlined. The image on the right shows an eye with guttae, which would be diagnosed as Fuchs dystrophy.

SYMPTOMS      

Glare and sensitivity to light Poor vision upon awakening with improvement later in the day Eye pain Foggy or blurred vision Seeing colored halos around lights Difficulty seeing at night

TREATMENT: Cornea Transplants—what’s right for you?

The purpose of the epithelium is to act as a barrier to protect the cornea from dust, debris and bacteria. The stroma is the middle layer and makes up 90% of cornea thickness, mostly of collagen and other structural materials. Its purpose is to give the cornea its strength and dome-like shape. The endothelium is just one layer of cells located on the Descemet membrane (blue line in illustration above) and its job is to provide the appropriate balance of fluid in the cornea, keeping it thin and crystal clear. In patients with Fuchs’, the endothelial cells slowly deteriorate as tiny bumps called guttae accumulate on the Descemet’s membrane (photos in middle column). When this happens, the surrounding cells become damaged and cannot work. Since the remaining cells cannot keep up with pumping fluid, the cornea begins swelling (known as corneal edema). As a result, the cornea becomes thicker and cloudy, resulting in vision problems. In advanced cases, tiny blisters can form on the surface of your cornea which can be painful, so it is important to seek treatment prior to severe progression. A list of symptoms may be found to the right. Once you find that your vision is impairing your quality of life or causing you to cut back on activities, such as night driving, it is time to replace the diseased layer. Fortunately, we now have a minimally invasive way to do that with a transplant procedure known as DMEK.

In the past, there was just one option for transplants, called penetrating keratoplasty (PK) (figure A), which involves the surgical removal of the central two-thirds of the damaged cornea. It is then replaced with healthy donor tissue. The new tissue is held in place typically by 16 sutures. This full thickness transplant has the potential to provide clear vision after healing, however, the healing time can be upwards of a year and in some cases, the sutures may never be removed. The recipient must be careful with the eye to ensure the wound doesn’t rupture, even many years after a transplant. Since 20 percent of PK grafts reject, many patients require more than one surgery.

Figure A: PK

To give you better vision and faster recovery, the Cornea Research Foundation has been working since 2001, to pioneer a new option called endothelial keratoplasty. We have found that you can get the best possible vision and fastest recovery with a variation known as Decemet’s Membrane Endothelial Keratoplasty (DMEK) (figure B), which studies have shown provides optimal visual results with less adverse risks than with PK. The cornea is the thickness of a credit card, and DMEK replaces less than 1/20th of that thickness. With DMEK, only the damaged endothelium of the cornea is replaced (figure C). This tissue (see Layers of the Cornea) is carefully removed through a small incision, and the replacement donor tissue is rolled up, inserted and flattened out. Rather than sutures, the tissue is held in place with an air bubble, resulting in faster healing.

Figure B: DMEK

Figure C: DMEK

Notice the anterior surface of the cornea remains intact with DMEK which leaves the eye much stronger and less prone to Arrow represents injury and the eye appears healthier just 7 days after surgery DMEK tissue thickness (figures A and B, compared), all significant improvements over PK. Visual recovery is also much faster with DMEK because the air bubble that holds the tissue in place while it attaches is much less traumatic than sutures. In some cases, patients may experience visual acuity as good as 20/20 just a few days after surgery with glasses. Most importantly, the rejection risk is 15 to 20 times lower with DMEK. Such low rejection is unprecedented and essentially eliminates one the main reason that transplants fail. In summary, research has shown that DMEK is now an excellent treatment option for patients with Fuchs’ dystrophy.