Around two million Germans suffer from esotropia, i.e. have a condition we refer to as being cross-eyed. This eye disease is one of the most common maladies to affect both of their visual organs. The problem is hereditary. Important to know: Being cross-eyed is by no means only a cosmetic defect. The eyes of children who have strabismus sit at a false angle from one another, causing the child to see mostly double images. To counter-balance this unpleasant state, the brain uses a trick: The eye that is not affected by the disease begins to do all the work alone and the other eye is “shut down.” The result: The unused eye continues to weaken and eventually goes nearly blind, although it would actually be fully functional if correct. The biggest problem: From around the age of 6, all the visual processes are so set in their ways that any treatment initiated after that age will not be successful. Experts differentiate between several different types of esotropia:
- Latent esotropia (heterophoria)
An eye muscle imbalance is present. The brain largely counter-balances this type of esotropia. Fatigue and stress can lead to headaches and eye pain.
- Concomitant esotropia (heterotropia)
The eyes do indeed move in a uniform, coordinated manner in all lines of vision, but they are not trained on the same object. The squint angle is the same in all lines of sight. Treatment in childhood is very important for this eye disease in order to prevent a lasting visual impairment of the affected eye.
- Paretic esotropia (paresis)
Usually the result of a neurological disease, an accident or impaired functioning of one or multiple eye muscles.
Important information: A baby cannot focus on objects yet, so it is normal if the eyes are not parallel at times. The condition becomes problematic when one eye consistently deviates from the direction of the other eye. Another possible warning sign is if the child is “clumsy.” It can sometimes be difficult for parents to assess whether the child is cross-eyed or not. An examination by an ophthalmologist will provide certainty.
Treatment options for the different types of esotropia vary. The most common is the occlusion therapy. An eye mask is placed over the “good” eye to force the impaired eye to do its work. Sometimes placing a cover over one side of the spectacles does the trick. Either way, the brain is compelled to support and train the weak eye.
The earlier this treatment is initiated, the greater the chances of success. If the esotropia persists despite all of these efforts, surgery can be performed on the affected eye on pre-school age children.
The name cataract comes from the Greek word for waterfall. In ancient times, scholars were of the opinion that the recognisable grey colour of the person’s pupils was trickling water. Today we know better: Proteins that clump together in the lens of the eye are to blame for this opacity. Nicotine consumption is the culprit in most cases, but diabetes and UV rays can also be triggers. Cataract sufferers thus feel as if they are always looking through frosted glass. Fortunately, excellent options are now available to treat this disease. The clouded lenses are removed in outpatient surgery and replaced by artificial lenses, a routine procedure that doctors perform 500,000 times every year in Germany alone.
This eye disease is much more malicious because it does not cause any pain. Increasing internal eye pressure leads to insidious retinal damage and finally to the deterioration of the optic nerve. In Germany, the disease is called “grüner Star” (green star), because when the internal eye pressure is very high, a person can see a green halo around light sources. The disease is only curable if detected early. Special medication (eye drops) can save the eyesight. Consequently, it is imperative that the eyes be examined regularly. Once nerve fibres are lost, they can never be recovered.
Age-related macular degeneration (AMD)
Around 4.5 million people in Germany suffer from this eye disease. AMD is a typical seniors’ malady, usually appearing in old age. The retina is no longer supplied as well as it once was, and cells begin to gradually die off. The early stage of this disease can be detected in a short eye test. For example, if an AMD sufferer looks at a gap between tiles in the bathroom, he/she will suddenly see a bend that isn’t really there. In the early stages of this disease, the gap in the bathroom will suddenly have a small bend.
Once degeneration progresses, vision cells in the retina at the point of sharpest vision, called the macula, gradually decay. Only the peripheries are spared from deterioration. As a result, if someone with AMD were to look at a street, for example, he/she would see the houses on the right and left, but not the cars on the road. The eye disease appears in two variants:
- Dry AMD
The so-called pigment epithelium under the retina decays and the vision cells die as a result. Over 80% of AMD patients suffer from the dry form of the disease. It develops slowly, over the course of years. There are still hardly any treatment options for AMD sufferers. For most patients, a magnifying visual aid can at least help see well enough to read.
- Wet AMD
Wet AMD progresses much more aggressively than dry AMD. In this form as well, the pigment epithelium decays and the vision cells die off. A characteristic of the wet form, however, is that blood vessels grow in the retina. These new small blood vessels bleed easily. The retina swells as a result, and patients see distorted images. The exsanguinous small blood vessels also leave behind scars on the retina. Special medications help in the early stage of this eye disease. They inhibit the growth of the blood vessels under and inside the retina. Laser therapy, or the so-called photodynamic therapy, helps some people. New surgical operations on the retina are being tested in some clinics.
Diabetic retinopathy is one of the most common causes of blindness in old age. It usually develops as a result of diabetes and is a retinal disease. The permanently increased blood sugar levels lead to mutations in the retina’s blood vessels, causing visual disorders and eyesight loss. Doctors differentiate between three different forms:
- Non-proliferative diabetic retinopathy
Vessel mutations are limited to the retina. In most cases, those afflicted do not notice anything.
- Proliferative diabetic retinopathy
In cases of advanced disease, new vessels can form that can proliferate from the retina out to the vitreous body. In addition to bleeding, this can also cause the retina to become detached. Vision is already considerably deteriorated.
- Diabetic maculopathy
Fat deposits, swelling and leaking fluid threaten the macula, the point of sharpest vision. Further progression can lead to blindness.
It is therefore very important that all diabetics be properly adjusted. Unfortunately, this is not always the case. Laser treatment can slow blood vessel mutation at an early stage. In case of advanced illness, complex surgery is required to keep the patient from going blind.
It burns, it itches and it feels like tiny grains of sand over the pupils. Blinding sun, acrid exhaust fumes, airborne pollen, dust and computer flickering can trigger these unpleasant symptoms. Normally, lachrymal fluid rinses the foreign particles from the eye and supplies the eye with oxygen and nutrients.
But the wet film can run dry, leading to the well known feeling of having a grain of sand in your eye. The most common triggers are staring at the screen for too long, dry ambient air and car air-conditioning systems. Hormonal disorders and medications, such as birth control pills or beta blockers, can also cause these conditions.
However, the cause may be something other than insufficient lachrymal fluid production. Sometimes the consistency is not right. So-called “synthetic tears” are the best help for both forms. This is when drops or gels serve as tear replacements. The drops are poured into the lower conjunctiva sac. Then, with the eyelids shut, one should “roll” his/her eyes to distribute the substance.
Caution: Using drops for too long and too frequently can cause the eye to produce less and less lachrymal fluid. It is therefore important to discuss the causes with your doctor and remedy them when possible (changing pills, avoiding stimulants).
One more tip for recreation: Wear goggles when swimming in heavily chlorinated pools. Surgery should be considered as a last resort if topical treatment does not help. Dr. Mehrle: "In the process, the draining lachrymal ducts are either completely or partially closed so that the lachrymal fluid does not flow out as fast."
Someone suffering from this eye disease can still read a newspaper or a book because he/she sees the world in a sort of tunnel vision. Retinitis pigmentosa is a genetic disease that affects around 40,000 people in Germany.
Due to a hereditary defect, the photosensitive cells in the retina gradually die off. The rods responsible for night and mesopic vision are the first to go. Typically, the cells decay from the outside in. The macula in the centre of the eye is spared at first, so patients with this eye disease can continue reading for a long time. In severe cases, all cells eventually die off.
In the majority of cases, this disease starts at a young age. Both eyes are equally affected. At first, people with retinitis pigmentosa can no longer see well at twilight, then they have night blindness and finally only a small tunnel remains.
Tinted visual aids that prevent excessively strong glare can help. Advances in genetics and molecular biology are raising hopes. Experts hope that it is only a question of time before a successful therapy is possible.
Doctors at the University Clinic in Aachen have celebrated initial success. They developed a completely implantable visual prosthesis which they have used on six patients. The prosthesis functions wirelessly. It is linked to a camera that sends image signals to the implant – wirelessly. A part of the nerve cell must still be intact in order for the implant to be successfully used.
Flashes of light / Retinal detachment
People who see flashes of light when their eyes are closed should make an appointment with the eye doctor because this symptom is characteristic of age-related vitreous change.
The reason for this eye disease: Over the years, initially harmless deposits form in the vitreous body, and collagen fibres clump together. Water-filled gaps form because the glass body liquefies. During eye movements, the firm structures floating inside them are perceived as moving shadows, thin threads or fluff balls. These so-called mouches volantes are disruptive, but are not yet dangerous and do not require treatment.
If the liquefaction progresses, however, the vitreous bodies can become completely or partially detached from their base. There are two different forms: Incomplete and complete vitreous body detachment.
In case of incomplete detachment connections remain between the vitreous body barrier and the retina. When people suffering from this disease move, tensile forces occur in the retina, causing flashes of light. Once the vitreous body is fully detached, the flashes of light disappear. In case of complete vitreous body detachment the retina can break down, leading to retinal detachment and even vitreous body bleeding.
For diagnosis, the doctor examines the vitreous body with a slit lamp and a contact lens and inspects the fundus of the eye. These complications must be treated as soon as possible because surgery is required for retinal detachments.