As a projection surface, the retina makes a central contribution to visual perception. Various diseases can impair the function of the retina to a greater or lesser extent. These include circulatory disorders, diabetic retinopathy and retinal detachment.
Below you will find further information and selected specialists for retinal diseases.
The inner eye skin (retina from the Latin rete, "net") surrounds the eyeball together with the middle outer skin (iris, ciliary body and choroid) and outer eye skin (sclera and cornea).
The retina is the transparent, light-sensitive tissue at the back of the eye @ Kristof /AdobeStock
After the light enters the eye through the pupil, it passes through the transparent vitreous body and hits the retina. Complex nerve cells in the retina convert the light into nerve impulses and transmit them to the brain via the optic nerve. This is where images are formed .
Sagittal section of the eye - the retina lines the inside of the eyeball
As a projection surface, the retina makes a central contribution to visual perception.
The retina lines the inside of the eyeball. It lies directly on the choroid, which is responsible for supplying the retina with nutrients. The light falling on the retina stimulates the sensory cells, which transmit these signals to the relevant regions in the brain.
The retina is covered with different types of nerve cells, which can be divided into three types:
The structure of the human eye
The photoreceptor cells are made up of two types:
The eye has 120 million rods, which are responsible for distinguishing between light and dark. Around 6 million cones enable color vision.
There are three types of cones that react to different wavelengths of light. These three wavelength ranges of light appear to us as red, green and blue.
The rods are located around the visual cortex to ensure the best color recognition.
The cones, which are sensitive to light and dark, are grouped in the peripheral area. For this reason, light and dark can be better distinguished in the corner of the eye, but colors cannot be perceived well. Color vision also decreases in poor lighting conditions . The photoreceptor cells regenerate regularly.
At the back of the retina, opposite the pupil, is the approximately 3 mm large "yellow spot" (macula). The pigments stored here can filter high-energy UV light and protect the retina from harmful effects.
In the center of the macula lies the fovea centralis. This is the area of the eye that enables the sharpest vision (e.g. for reading). The rest of the retina, on the other hand, is responsible for the peripheral field of vision, i.e. for "looking out of the corner of the eye".
The optic disc is slightly offset from the macula. It is the point at which the retinal nerve fibers bundle to form the optic nerve . Together with the blood vessels, they leave the eyeball through all layers of the eye skin. There are no light receptors at this point to catch the incoming light. It is therefore a "blind spot" in the truest sense of the word .
View of the retina at the back of the eye during an ophthalmoscopy: the macula in the center, the optic disc on the right
The retina can be more or less severely impaired in its function due to various diseases. Pain does not occur as it has no sensory cells. You should therefore have your eyes and retina checked regularly by an ophthalmologist.
There are a variety of circulatory disorders of the retina. Various underlying diseases are possible causes. Without good blood circulation and optimum supply to the nerve cells, the retina cannot fulfill its function. Circulatory disorders in the eyes can also lead to impaired vision. In the worst case, this can lead to blindness.
There are many different underlying diseases that can cause circulatory disorders in the retina. If the underlying disease is successfully treated, doctors can often also correct the visual impairment. In a chronic condition, however, vision deteriorates continuously.
One possible cause of visual impairment is diabetes (diabetes mellitus). This is referred to as diabetic retinopathy. Black spots appear in the field of vision, indicating the onset of blindness. There may also be a blockage of the central or lateral arteries or veins of the retina.
It is important to control diabetes in order to prevent such visual disturbances. If doctors treat the underlying disease efficiently, they can ensure that the retina is adequately supplied with blood.
This is a generic term for various genetic diseases of the retina. In all diseases, the visual field gradually becomes smaller. They are progressive and incurable.
Possible symptoms are
This results in so-called tunnel vision. It seems as if you are looking through a tube because the edges of the visual field are blocked. This is where the blood vessels in the retina constrict. A yellow discoloration develops on the optic disc. There is still no cure for this disease of the retina. Prevention is also not possible.
Retinal detachment is a serious and very sudden disease. In this case, the retina detaches from the choroid. This leads to an insufficient supply to the photoreceptor cells. They eventually die. Those affected do not notice this through pain, but through a blind spot in the field of vision.
In retinal detachment, the retina no longer receives enough oxygen and nutrients from the choroid @ bilderzwerg /AdobeStock
There are various causes for this disease. Genetic factors are usually responsible.
Other factors that cause retinal detachment:
Seeing flashes or permanently flickering spots are symptoms of retinal detachment and the field of vision becomes blurred. In this case, you must consult an ophthalmologist immediately, who will immediately initiate an operation to prevent blindness.
The Leading Medicine Guide's quality assurance is ensured by the following acceptance prerequisites.
