What Is Fuchs’ Dystrophy?
Fuchs’ dystrophy (also called Fuchs’ corneal dystrophy and Fuchs’ endothelial dystrophy) is a gradual deterioration of the innermost layer of the cornea, the corneal endothelium. This eye disease usually affects both eyes and causes a gradual decline in vision due to permanent swelling and clouding of the cornea.
The inner layer of the cornea, the endothelium, is responsible for maintaining the proper amount of fluid in the cornea needed for clear vision, pumping out excess fluid that could cause corneal swelling. If the endothelial cells begin to gradually die and the endothelium is not able to properly pump out fluid, swelling occurs, which results in blurred vision. Advanced stages of the disease can result in small blisters forming on the surface of the cornea, a condition known as bullous keratopathy. These blisters can cause pain and irritation.
The causes of Fuchs’ dystrophy are not fully known, although the disease can be inherited through family genetics and the symptoms can sometimes be quickened after trauma or eye surgery, even if the surgery went perfectly.
While the earliest signs of Fuchs’ dystrophy may be visible in people in their 30’s and 40’s, most people don’t develop symptoms of this slow progressing disease until they reach their 50’s or 60’s. These symptoms include:
- Glare and sensitivity to bright light
- Blurred or cloudy vision, which can be worse in the morning and decrease throughout the day
- Difficulty seeing at night
- Eye pain
- Gritty feeling in both eyes
- The sensation of something being in the eye
- Reduced vision in humid weather
- The appearance of halo-like circles around lights
Your ophthalmologist can determine the presence of Fuchs’ dystrophy through a comprehensive eye exam, as they look for subtle changes in the appearance of cells in the endothelium that are characteristic of the disease, measure for the increased corneal thickness that might indicate corneal swelling, and check the corneal pressure.
In the early stages of the disease, vision often can be improved through the use of 5% sodium chloride (hypertonic) eye drops, which removes excess water from the cornea and reduces swelling. Based on the condition of your eyes, your eye doctor might also recommend eye drops to reduce your intraocular pressure (IOP). High eye pressure can damage the corneal endothelium, worsening Fuchs’ dystrophy. Wearing soft contact lenses can also help by acting as a covering for the cornea and relieving pain.
For advanced stages of the disease, when significant vision loss has occurred or when the epithelial blisters have the potential to rupture, causing painful corneal abrasions and poor vision, a cornea transplant is usually needed. Most people who have surgery for advanced Fuchs’ dystrophy can look forward to having much better vision after the procedure and remain symptom-free for years afterward.
Rather than removing the full thickness of the cornea, as in standard corneal transplants, the cornea specialist at Ophthalmic Consultants of the Capital Region uses the following advanced procedures:
- DMEK (Descemet’s membrane endothelial keratoplasty)
- DSAEK (Descemet’s stripping automated endothelial keratoplasty)
- PDEK (Pre-Descemet’s membrane endothelial keratoplasty)
DMEK, DSAEK, and PDEK are all partial thickness corneal transplants that replace primarily the endothelium, the innermost portion of the cornea, as well as the Descemet’s membrane. This is different than standard corneal transplants, which replace all layers of the cornea: the epithelium, stroma, and endothelium. Because Fuchs’ dystrophy is the result of only the diseased endothelium layer of the cornea, the other layers of the cornea remain healthy and can remain untouched.
What is the difference between the procedures?
All three procedures are very similar. In a DSAEK procedure, the endothelium, Descemet’s membrane, and some of the stromal tissue of the cornea are replaced. In a DMEK procedure, only the endothelium and Descemet’s membrane are replaced, which tends to give better visual results and a quicker recovery, although donor disc with or without K dislocations and failures can be more common.
DSAEK/DMEK is a state-of-the-art procedure and continues to be refined. One advancement includes the introduction of the advanced PDEK procedure. The PDEK procedure replaces the endothelium and Descemet’s membrane like the DSAEK and DMEK surgeries. However, it also replaces a recently discovered microscopic layer between the stroma and Descemet’s membrane called Dua’s layer. This alteration allows for faster visual recovery and less postoperative inflammation.
Talk with our cornea specialist about which procedure option may be right for you.
Advantages of DSAEK/DMEK/PDEK compared to standard corneal transplantation:
- Visual recovery time is significantly faster
- Less post-operative astigmatism (abnormality of the shape of the cornea)
- Reduced discomfort
- The wound is smaller and closer in size and location to cataract surgery, meaning it is more stable and less likely to break open from the trauma
- May decrease the incidence of rejection
- Greater structural integrity
- More than 90 percent of the patient’s own cornea is still in place after surgery
About the Procedure
The procedure usually takes about 30 minutes to perform and is done in an outpatient setting. Only local anesthesia is needed, and the procedure is done through a small incision on the side of the cornea. The diseased endothelial layer is peeled from the back of the cornea, leaving the healthy remainder intact (approximately 95 percent of the cornea). Then, a donor disk (with a k) of healthy corneal tissue is placed inside the eye through a small incision and positioned with an air bubble in the place of the diseased layer.
After surgery, the eye is patched and minimal discomfort should be experienced, although standard over-the-counter pain medications can be taken, as needed. Your ophthalmologist will give you other medications for the eye, including antibiotic and steroid drops to prevent infection and to help with healing.
For the first 24 hours, it is best to lie down on your back, facing the ceiling, as much as possible. Patients will return for follow-up appointments the day after the procedure, as well as a week later, and again in one to three months.