LaserVision shall be highlighting a different eye condition each month with the aim of raising awareness of these conditions and symptoms. This month we’re focusing on FED.
Fuchs’ Endothelial Dystrophy (FED)
Symptoms: In the early stages of the condition, vision tends to be blurred on waking in the morning. This clears often in an hour or two. This occurs as the cornea is normally thicker in the morning, and it retains fluids during sleep that evaporate in the tear film while we are awake. But as the dystrophy worsens, this swelling will remain constant and reduce vision for longer and eventually blurred vision remains throughout the day. In the most severe cases the cornea forms blisters that can cause pain.
What is Fuchs’ Endothelial Dythrophy? Fuch’s endothelial dystrophy (FED) is a slowly progressive disease. There is a slow loss of endothelial cells from the inner layer of the cornea. If the number of cells drops below a critical density the cornea will begin to become cloudy and blur the vision. Although early signs of the dystrophy can be seen in people of their 30s and 40s, the disease rarely affects the vision until the person reaches their 60s or later. Happily, many patients may have microscopic signs of FED without ever having any significant visual symptoms.
Cause: Fuchs dystrophy occurs when endothelial cells (the back layer of the cornea) gradually deteriorate without any apparent reason. With time the endothelial cells are lost, preventing the cornea from effectively pumping water out of the stroma (middle layer of the cornea). This causes the cornea to swell and distort vision. Eventually, the epithelium (front layer of the cornea) takes on water, resulting in blisters which can cause pain and severe visual impairment.
Diagnosis: FED is often diagnosed by the optometrist or ophthalmic surgeon in the very early stages. A characteristic pattern in the inner layer of the cornea can be seen under the microscope. This can often be diagnosed many years before visual symptoms develop.
Monitoring can be by watching for the visual symptoms such as blurred vision in the mornings. Measurements in the clinic can be performed. The corneal thickness can be measured. The thickness will increase as the condition deteriorates. The density of cells can be monitored using an endothelial cell counter.
Treatment: The early stages do not require treatment. There is unfortunately no known way of preventing the condition from deterioration. However, many patients deteriorate very slowly and often do not suffer any significant visual deterioration. Some cases may improve using ointments to reduce the swelling, or by the use of a hair dryer, held at arm’s length or directed across the face to dry out the cornea or the blisters if they are very uncomfortable.
In more severe cases when the disease starts limiting one’s lifestyle by making daily living more difficult, a corneal transplant may be considered to restore sight. Your LaserVision consultant surgeon can expertly guide you through the best treatments for you. Read more about the possible treatment options here and book your consultation with us today if you think you may have these symptoms.