Diseases of the retina

In general, diseases of the retina are painless because there are no pain fibers in the retina. A retinal detachment results in a separation of the retina from the choroid, which is rich in vessels. A space is formed in which fluid accumulates.

As a result, the retina can no longer be supplied by the choroid and visual disturbances occur. Causes of retinal detachment can be inflammation, degeneration, hole or tear formation. The latter are formed by weak points or for example by bruises of the eyeball.

Fluid passes through the hole and the retina is detached. Since in most cases no pain is felt, a retinal detachment can usually be detected by blurred vision. If the tears in the area of a blood vessel caused by degeneration are present, it can lead to small visible bleedings in the eye.

If the retina has detached in the area of the fovea centralis, sharp vision is no longer possible. Furthermore, there is reduced light perception in the area of the detached part. This is often perceived as a kind of veil in front of the eye.

In most cases, the reason for a retinal detachment is an age-related tear or hole formation. The reason for this cracking is the shrinking of the so-called vitreous body inside the eye, which increases with age. Since this vitreous body is connected to the retina in some places, shrinkage of the vitreous body results in tension on the retina.

This results in tears. People who suffer from diabetes mellitus, who are short-sighted or have undergone surgery for cataracts have a higher risk of suffering from a retinal detachment. If the retina is torn, this can be repaired by laser therapy.

If the retina is detached, an operation must be performed. Unfortunately, holes in the retina or a retinal detachment cannot be treated with medication. Retinal detachments can be divided into a rhegmatogenous detachment based on a tear, an exudative detachment where fluid from the vessels of the choroid enters the retina, and a tractive retinal detachment.

The latter results in scar tissue. At the site of scarring, the tissue contracts and a traction is created. As a result, the retina can become detached.

In order to function properly at all times and to enable vision as a process, the retina must be constantly supplied by the blood vessels from the adjacent choroid. In case of a circulatory disorder, the vision can be impaired, which can lead to blindness, because the retina can no longer be supplied sufficiently. Both arteries and veins can be affected.

Basic diseases that can lead to an occlusion of a vessel and thus to a circulatory disorder are mainly diabetes mellitus, high blood pressure and arteriosclerosis. It is therefore important to have the parameters of these diseases constantly monitored. Arterially induced disorders manifest themselves in a spontaneous, painless and direct loss of vision in the affected area.If symptoms occur, an ophthalmologist should be consulted immediately within 24 hours so that there is a chance of recovery.

Venous-related failures do not manifest themselves so strongly and abruptly compared to arterial occlusions. The symptoms here are usually perceived as a kind of dark shadow or curtain. A frequent consequence of venous circulatory disorders is swelling in the area of the sharpest vision (macular edema), which greatly reduces visual acuity.

Often the retina tears in marginal areas without a recognizable reason and a hole is created. Normally, the retina of the eye wall lies against the inside of the eye. It is held in position by a suction formed by liquid.

If there is a tear in the retina, the suction is lost. The water from inside the eye gets into the interstitial space. This space becomes increasingly filled with fluid and the retina detaches itself.

The retina can be completely detached within a few days. The original cracks in the retina usually appear as fast and bright flashes or as many small black dots that seem to float around in front of the affected person’s eye. Once the retina has detached, severe visual field failures occur.

If symptoms are perceived, an ophthalmologist should be consulted as soon as possible. If the retina has not detached at this time, laser therapy is sufficient in most cases. Here, a laser beam triggers an inflammatory reaction at the affected area, which scars the tissue at the site of the hole and thus closes it.

If the retina is already detached, laser therapy is no longer helpful and surgery is required. A pure inflammation of the retina is called retinitis. Since the retina and the choroid are closely connected, the choroid directly next to it is usually also affected.

Therefore, the inflammation of the eye background is also called chorioretinitis. The inflammation of the retina is painless. At the beginning it also runs without symptoms.

Only in the later stage of the inflammation does the affected person often develop a veil in front of the eyes or clouding of the visual field. The extent of the symptoms depends on the location of the inflammation on the retina. The closer it is to the point of sharpest vision, the more severe the visual impairment.

The cause of retinal inflammation is usually bacteria, viruses or fungi that penetrate the retina. Furthermore, diseases such as rubella, herpes, syphilis or autoimmune diseases can be the cause of retinal inflammation. To fight the inflammation, antibiotics are usually administered by means of eye drops. Due to its anti-inflammatory effect, cortisone is also often used. In severe cases, the antibiotic must be injected by means of a syringe.