Coats Disease

Coats’ disease is a congenital eye disease caused by a genetic defect. Coats’ disease leads to complete blindness and can only be cured to a limited extent.

Coats Disease

What is Coats disease?

Coats ‘ disease is a rare congenital eye disease that affects boys far more often than girls. The blood vessels of the retina are dilated and permeable, allowing blood and eye fluid to pass under the retina. See lawfaqs for Definitions of Lesser-Trélat Syndrome.

This causes edema, which – if the disease is left untreated – leads to the detachment of the retina and ultimately to complete blindness.

Coats’ disease usually occurs on one side – a typical feature is a milky white film over the eye.

Usually there is no pain. Sometimes a glaucoma is caused by the increase in intraocular pressure. Less than 10 percent of those affected have no symptoms at all. In the long term, Coats’ disease basically threatens complete blindness.


The causes of Coats’ disease are currently unknown. However, numerous studies in the family environment of those affected allow the conclusion that there is a hereditary predisposition to the development of Coats’ disease.

Retardation of the X chromosome is suspected. The cause of the blindness that Coats’ disease usually causes is the defective blood vessels in the eye. As a result of this defect, bulges (aneurysms) develop in the blood vessels of the retina, which cause the blood vessels to become porous and allow fluids to leak out.

The liquids (blood, cholesterol crystals, lipids) are deposited under the retina and subsequently lead to a detachment of the retina. As a result, the patient’s vision will deteriorate more and more and ultimately lead to blindness.

Symptoms, Ailments & Signs

The first symptoms of Coats disease usually appear in the first or second decade of life. Boys are affected much more often than girls. In addition, in over 90 percent of cases it is a unilateral eye disease caused by aneurysms in the blood vessels of the eye. Secondary strabismus and leucocoria are usually observed as the first symptoms.

In leukocoria, the fundus of the eye does not appear red as usual in photographs taken with a flash, but white. Patients often only have blurred vision in the affected eye. Spatial vision is impaired. However, the loss of vision in small children often goes unnoticed at first.

However, not every course of the disease is the same. The progression of the disease can thus come to a temporary or even permanent standstill.

In a few cases, an improvement in symptoms was even observed. However, in most cases a retinal detachment occurs, which then leads to blindness in the affected eye. The course of the disease is often much more fulminant in children under the age of five than in older children. In severe cases, removal of the eyeball may be necessary.

Diagnosis & History

If Coats’ disease is suspected – secondary squinting can be a first, visible sign – the ophthalmologist will perform an ophthalmoscopy (examination of the back of the eye). To do this, the doctor illuminates the back of the eye and can thus identify changed blood vessels. The examination is painless and only takes a few minutes.

Patients suffering from Coats’ disease initially show a secondary squint. It is also particularly noticeable that eyes photographed with a flash light do not appear red but milky white. During this phase of the disease, the patient’s three-dimensional vision is limited, and he only perceives images as blurry. The course is usually painless – only when the intraocular pressure increases does the patient feel pain in the eye.

The increase in intraocular pressure can lead to “glaucoma,” a common comorbidity of Coats’ disease. In affected small children, the disease usually goes unnoticed because they are not aware of the constant loss of their vision. Moreover, each patient’s course is different – while most patients experience continuous deterioration, some patients report intermittent deterioration. In a few cases, regression was even observed. As a rule, however, Coats’ disease leads to a complete detachment of the retina and thus to complete blindness.


Coats’ disease causes severe eye discomfort and vision loss in those affected. In the worst case, this can also lead to complete blindness, which can usually no longer be cured. It is not uncommon for visual problems or blindness to lead to severe psychological limitations or depression.

Those affected often suffer from inferiority complexes or reduced self-esteem. Dealing with vision loss is relatively difficult, especially for young people. Those affected can continue to squint and only see blurry. Blurred vision and, in some cases, double vision.

Furthermore, a glaucoma or a cataract can form and the eyes have different eye colors. Complete blindness usually only occurs if the disease is not treated. The treatment itself can be carried out relatively easily and does not lead to any particular complications.

The visual problems can thus be solved and complete blindness can be prevented. There are no particular complications. Furthermore, the pain is also reduced by the treatment. Coats disease does not lead to a reduction in life expectancy.

When should you go to the doctor?

In the case of visual impairment, a doctor is always required. If the eyes are misaligned or there are other peculiarities of the pupils, a doctor should be consulted. Burst blood vessels in the eyeball, reddening of the eyes and clouding of the cornea must be examined and treated by a doctor. Since Coats’ disease is a genetic condition, in many cases an abnormality is detected immediately after birth. The diagnosis can often be made after the first examinations shortly after delivery. In a routine process, the newborn is examined intensively by the nurses, midwives or doctors present. The dysfunction of the eyes can therefore already be tested at this stage of life.

If parents notice any abnormalities in their children’s vision during the growth and development process, they should consult a doctor immediately. If there are more accidents in everyday life or if the toddler regularly reaches next to objects, he needs medical help. If the suspicion arises that there is a complete inability to see, it is advisable to see a doctor for a check-up as soon as possible. If the child cries continuously, this can be an indication of existing pain or severe internal pressure in the eye. A doctor must be consulted so that treatment can be initiated.

Treatment & Therapy

If Coats’ disease is detected early – i.e. before the first detachments of the retina – it can be treated well. The aim is to preserve part of the eyesight. An ophthalmologist can localize changed blood vessels and in a subsequent step use a laser to obliterate them.

Good treatment successes can also be achieved in this phase of the disease with cold therapy. Both therapies prevent the escape of fluid and thus prevent detachment of the retina. If Coats’ disease is more advanced and the retina has already become detached, Coats’ disease can no longer be treated curatively. The doctor can only remove the affected part of the vitreous body of the eye and/or the retina.

In order to exclude a malignant background – such as a retinoblastoma – it can be helpful to completely remove the eye. Vision cannot be restored after the retina has been detached – the interventions described can only relieve the intraocular pressure and thus reduce or completely eliminate pain in the eye.

Outlook & Forecast

Coats’ disease offers a relatively good prognosis. Usually only one eye is affected by the disease, which can be surgically removed. Those affected can then lead a normal, symptom-free life. However, Coats disease has a high risk of recurrence. In the event of a relapse, the therapeutic measures must be repeated. Drug treatment of pain is associated with side effects and interactions.

If left untreated, the disease progresses progressively and leads to complete blindness in the affected eye. An effective treatment is not yet available. Therapy focuses on removing the diseased parts of the body and treating the pain with medication. Well-being is reduced during treatment. Normal life is often possible after the therapy is completed.

In the case of complete blindness, the sufferers are dependent on help for the rest of their lives. Life expectancy is not reduced if the retinal edema has been completely removed. Further preventive measures are necessary to avoid a relapse, which is usually more severe and significantly worsens the prognosis. The doctor makes the prognosis, taking into account the symptoms and the chosen therapy.


Since a hereditary background is suspected in Coats’ disease , the current state of medical research cannot prevent it. If Coats’ disease is detected early, however, the consequences of the disease – usually complete blindness – can be prevented. There are a number of prophylactic therapies to choose from that aim to preserve part of your vision.


After treating Coats’ disease with laser therapy, the patient should avoid physical exertion for a few days. Active participation in road traffic is not possible 24 hours after the treatment. In the event of any abnormalities or complaints, the doctor treating you must be informed immediately. He also decides when it is time for the first check-up and whether eye drops or eye ointment need to be prescribed after the procedure.

Coats disease can only be treated symptomatically. The symptoms can therefore flare up again at any time, even after successful therapy. In addition, Coats’ disease increases the likelihood of developing increased intraocular pressure (glaucoma) or clouding of the lens (cataracts). Therefore, regular ophthalmological checks are essential. The treating ophthalmologist determines the interval between the examinations.

In some cases, despite regular therapy and monitoring, a gradual loss of vision cannot be stopped. In the worst case, patients lose the affected eye. This represents a great psychological burden for the mostly very young patients, which is why psychological care should be considered. Support from trained specialists facilitates healthy psychological development and supports the self-confidence of those affected.

You can do that yourself

The congenital disease is based on a genetic defect. The possibilities of self-help are very limited with this disease. Despite all self-responsible attempts, a cure cannot be achieved. In everyday life it is important to maintain and improve well-being. Joie de vivre should be promoted so that the patient has sufficient emotional resources available when dealing with the disease. A positive basic attitude, words of encouragement from relatives and a stable social environment help the patient to cope with everyday life.

Although many activities cannot be carried out because of the symptoms, children’s sense of achievement should be encouraged. An exchange with other sufferers or in self-help groups can help to get mutual support and tips. Open questions are clarified so that the complaints can be better dealt with in the daily routine.

The patient should be informed in good time and comprehensively about his illness and the consequences. A self-confident and honest handling of the disease is helpful for the entire environment. This reduces inappropriate comments or unwanted behavior. In a large number of cases, people from the immediate vicinity experience their own insecurity or overwhelm with the situation due to ignorance, which leads to misunderstandings or hurtful events for the person concerned. This should be prevented if possible.