Fuchs’ Corneal Dystrophy
Fuchs’ dystrophy (named after Dr. Fuchs) is an inherited condition that affects the delicate inner layer (endothelium) of the cornea. Patients with Fuchs’ dystrophy have endothelial cells that do not function as efficiently as normally and deteriorate more rapidly than normal cells.
Fuchs’ dystrophy affects both eyes and is slightly more common in women then men. On average, half of the family members of an affected person may carry or suffer from the condition. The exact cause of Fuchs’ dystrophy is unknown. Hereditary, hormonal and inflammatory factors probably all play a role.
Signs and Symptoms
In early stages, people with Fuchs’ dystrophy may wake up with blurred vision, which gradually clears over the day. That’s because during the day, water continuously evaporates from the surface of the eye and is replaced with water drawn from the inner compartments of the eye. Overnight, when we sleep with closed eyes, water cannot evaporate from the surface of the eye and accumulates in the cornea, causing slight swelling which blurs vision. Once eyes are opened throughout the day, evaporation reduces the water content and the thickness of the cornea, allowing for clearing of vision. In later stages, as the dystrophy worsens, evaporation is not enough to remove accumulated water in the cornea, and swelling and blurred vision last all day.
Typical complaints among people with Fuchs’ dystrophy include:
- Hazy vision that is often most pronounced in the morning
- Fluctuating vision
- Glare when looking at lights
- Light sensitivity
- Sandy, gritty sensation
- Episodes of sharp, sometimes incapacitating pain
Detection and Diagnosis
Although Dr. Vold can often see early signs of Fuchs’ dystrophy in people in their 30s and 40s, the dystrophy rarely affects vision until people reach their 50s and 60s. Fuchs’ dystrophy is detected by examining the cornea with a slit lamp microscope that magnifies the endothelial cells thousands of times. The health of the endothelium is evaluated and monitored with pachymetry (which measures the thickness of the cornea) and specular microscopy (which photographs the cells for counting). As the dystrophy becomes more advanced, corneal clouding may make counting the cells impossible.
Fuchs’ dystrophy cannot be cured. Dr. Vold cannot treat the endothelial cells to make them work better or to become more numerous. However, blurred vision resulting from the corneal swelling can be sometimes be controlled with medication. Salt solutions containing sodium chloride (Muro 128 drops or ointment, 2% or 5%) are often prescribed to draw fluid from the cornea and reduce swelling. Steroid eye drops may be helpful in specific situations.
A corneal transplant is considered when vision deteriorates to the point that it interferes with daily activities and impairs a person’s ability to function normally. This surgery replaces the full thickness of the cornea, including the endothelium, with healthy layers. The cloudy cornea is replaced with clear corneal tissue.
Fuchs’ Dystrophy in Patients with Cataracts
As people age, the lens within the eye often becomes cloudy, developing into a cataract. Cataract surgery is very common and has a very high success rate. Any eye surgery causes some damage to the delicate endothelial cell layer of the cornea, causing a reduction in the number of cells remaining to pump water from the cornea. If the number of endothelial cells is insufficient following cataract surgery, corneal swelling will develop, reducing vision. Corneal transplantation may be necessary to recover vision. When patients with Fuchs’ dystrophy develop cataracts, Dr. Vold will carefully evaluate the status of the endothelium to decide whether the cornea is likely to continue to function well following cataract surgery. A recommendation may be made to combine cataract surgery with corneal transplantation. One combined surgery can achieve what would otherwise require two separate surgeries with a longer post-operative recovery.