Fuchs Dystrophy Definition
Fuchs dystrophy, also known as Fuchs endothelial dystrophy, is a corneal disease that progresses slowly and generally affects both eyes and slightly more common in women than in men. In this disease, cells present in the inner surface of the cornea slowly start to die off. The disease does not affect the vision until patients reach 50 or 60 years of age. The early signs of this disorder are usually seen from the 30s and 40s.
The condition was first described by Ernst Fuchs after whom this disease has been named.
Fuchs dystrophy Stages
The condition passes through 3 clinical stages. The changes are bilateral over a period of 2 or 3 decades.
Picture 1 – Fuchs Dystrophy
The first stage is exhibited by mild or no symptoms at all. The stage is known as Cornea guttata. It takes place in the fourth or fifth decade of life. Pigment dusting is also noticed. The protrusions of the corneal guttata increase in number and may become confluent which leads to the eye taking the appearance of being a beaten metal on the endothelial surface. The condition spreads from the center towards the periphery. Generally, patients do not face any difficulty at this stage. The vision is worse in the morning and improves later in the day.
The second stage shows increasing visual problems resulting from incipient edema of the corneal stroma in the beginning and later the epithelium. Patients observe halos around lights and also experience blurred vision and glare. The epithelial cysts coalesce later and form bullae. The bullae rupture and expose the cornea to the danger of infectious keratitis. Patients experience the presence of a foreign body in the eye and pain. Corneal sensitivity is minimized by the destruction of the epithelial nerve endings.
In this stage, subepithelial connective tissue and formation of pannus along the epithelial basement membrane are observed. Bullae formation decreases. The epithelial edema is reduced so that patients get comfortable, although the stromal edema remains. The epithelial is strengthened by the pannus and fibrous tissue beneath it.
Fuchs dystrophy Causes
Fuchs dystrophy is an autosomal dominant disorder when inherited. Children of parents having this disease are at great risk of developing the condition. The disorder affects the thin layer of cells which line the back portion of the cornea. The layer is known as endothelium. This condition minimizes the number of specific cells which make up the inner layer of the cornea. Endothelial cells are essential for processing water which makes up the corneal cell structure. If these cells decrease in number, they stop processing water properly and fluid begins to accumulate. The corneal tissue gradually thickens and causes the cornea to become swollen and the eyes to get cloudy. It also results in a change of shape of the cornea which leads to further vision problems and eye pain.
Fuchs dystrophy Symptoms
In the early stages, patients wake up with a blurred vision which will clear as the day progresses. This occurs since the cornea is thicker in the morning, since it retains fluids during sleep which evaporate out into the tear film while we are awake. When the disease gets worse, the swelling remains constant and minimizes vision throughout the day.
The major symptoms include:
- Hazy or cloudy vision
- Sensitivity of the eyes towards light.
- Painful, small blisters on the surface of the cornea resulting from accumulation of excess fluid within the cornea.
- Seeing halos in color around lights.
- Difficulty in seeing at night.
- Reduced ability to differentiate contrasts.
- Distorted vision
- Worsening of vision throughout the day.
- Pain in the eye.
Fuchs dystrophy diagnosis
Doctors initially conduct a slit lamp examination, followed by other tests, to determine if a person has developed Fuchs dystrophy. A patient may be put through the following tests:
In this exam, a bright light is pointed at the eye while patients have to read the characters on the chart provided. This test helps to determine if bright light minimizes the ability to see.
Grade or guttata stage
Doctors use an optical microscope known as the slit lamp to examine the interior of the eye. The endothelial cells in the cornea are examined. If there are irregularities (known as guttae) on the surface of the cornea at the back, Fuchs dystrophy may be present. Once this test is over, doctors assign a grade to the result within 0-5. A “0” means absence of the condition and a 5 indicates that the eye has been severely affected by the disorder.
Corneal thickness test
This exam involves the use of ultrasound techniques to ascertain the thickness of the cornea. If the cornea is very thick it is quite likely due to an accumulation of fluid.
This is a fundamental ocular test performed during normal eye check-ups. Sufferers are asked to look at a chart with letters and numbers on it and read the characters. This test helps to detect if the eye condition has deteriorated since the last exam.
Corneal cell count
In this test, physicians make use of a special instrument which records the size and shape of the endothelial cells. It also measures the number of endothelial cells within a certain part of the cornea. A low cell count indicates that the disease has reached an advance stage. The test is usually performed before eye surgery.
Corneal pressure test
Doctors make the eyes numb with drops. After which the doctor will measure the pressure inside the eye using a special instrument.
Fuchs dystrophy Differential Diagnosis
A differential diagnosis for this disorder involves ensuring the absence of conditions that produce similar symptoms. These include:
- Corneal edema
- Corneal erosion
- Pseudophakic bullous
Fuchs dystrophy Treatment
Fuchs endothelial dystrophy cannot be prevented. Treatment includes applying topical nonsteroidal anti-inflammatory drugs such as diclofenac (0.1%), ketorolac (0.5%). The drops of these medicines will keep the following symptoms at bay like burning, gritty sensation and itching. However, it increases the risk of poor epithelial healing and which is followed by corneal melting. Ointments can be used to extract the fluid of the cornea. Sodium chloride (5%) eye drops can be instilled 4-6 times a day especially during the early hours of the morning and less frequently in the evening. Sodium chloride ointment is applied before going to bed. Glycerine can be used to dry the cornea and clear the vision.
Blowing warm air over the cornea by using a hair dryer (kept at an arm’s length) for 5-10 minutes after waking up in the morning can help dry the cornea and improve the vision for some time. Minimizing the pressure inside the eye can also be helpful when it is mildly raised. Patients of this disease should wear soft therapeutic contact lenses.
A transplantation of the cornea is the only permanent cure for this disorder.
There are many types of surgical procedures for the cornea. Some procedures replace only a few thin upper layers of the cornea and the others will replace the entire cornea. Deep lamellar endothelial Keratoplasty is an alternative to the traditional procedure of transplantation where only the deep layers of the cornea are replaced with donor tissue. This process requires no stitches. The recovery time is also fast and fewer complications occur. This method provides super visual results and patients are supposed to remain in face up position for 24 hours. This is done to let the transplanted tissue stick to the overlying cornea. A lot of improvisation has been brought about in this method for surgical instrumentation such as graft injectors. The process can also be carried out through very small suture-less cuts in the skin measuring only 3 mm.
Fuchs dystrophy Complications
Patients should be aware of the signs that show development of complications in the eyes. The signs usually include:
- Heaviness of the eye
- Pain in the eye
- Sensitivity to light
- Redness of the eye around the cornea
- Reducing eyesight
The possible complications include:
- Expulsive haemorrhage
- Graft rejection and failure.
- Wound separation.
- Aqueous leakage
- Loose sutures.
- Rejection of graft and failure.
- Infected keratitis.
- Epithelial healing problems and ulceration.
- Vitreoretinal issues-Retinal detachment, choroidal detachment and cystoids macular edema.
Fuchs dystrophy Prevention
Once surgical treatment is over, patients should protect their eyes well and take proper care to avoid complications. The following measures should be adopted to prevent complications:
Picture 2 – Fuchs Dystrophy Image
- Trauma to the eye should be avoided.
- The eye should be cleaned with boiled and cooled cotton swabs and not splashed at with tap water.
- Eyes should not be rubbed.
- Eyes should be protected with tinted non-reflective lenses on the glasses, wide brimmed hats and wraparound glasses when outside. This should be maintained for 3 months and more after surgery.
- Check-ups should be routinely. Doctor should check the vision, fundus and intraocular tension.
- The condition of the graft should be checked after every 15 days to check for rejection and infection.
Following operation, patients can watch television and resume visual tasks after 2 weeks.
Fuchs dystrophy Precautions
Sufferers should take the following precautions to safeguard their eyes.
- The eye should be cleaned with non-sterile products
- Avoid application of cosmetic on the margin of eyelid.
- Smoky and dusty environment should be avoided.
- No other drops should be given to the eye other than the ones prescribed.
- The nozzle of the eye drop bottle should not be touched while use.