Yellow dot
The macula lutea, also called the yellow dot, is the place on the retina with which people primarily see. It was named after the yellowish coloration of this spot when the back of the eye is mirrored. The yellow spot is the place on the retina with the most photoreceptors.
Outside the macula, there are almost only rods that are supposed to distinguish between light and dark. The macula also contains the central fovea, the so-called central visual fossa. This is the point of sharpest vision. The visual fossa contains only cones in their maximum packing density, whose signals are transmitted 1:1, so that the resolution is best here.
Dystrophy
Dystrophies, i.e. pathological changes in body tissue affecting the retina, are usually genetically anchored, i.e. they can either be inherited from the parents or acquired through a new mutation. Some drugs can cause symptoms similar to those of retinal dystrophy.
Common to these diseases is that symptoms only appear in the course of life and they have a chronic but progressive course. The course of dystrophies can vary greatly from disease to disease, but also vary greatly within a disease. Even within an affected family, the course can vary, so that no general statements can be made.
In some diseases, however, it can progress to blindness. Depending on the disease, the visual acuity can decrease very quickly, or even deteriorate gradually over several years. Also the symptomatology, whether the central field of vision changes first or the visual field loss progresses from the outside to the inside, is variable depending on the disease.
The diagnosis of retinal dystrophy can be difficult in the beginning. However, there are numerous diagnostic procedures that make a diagnosis possible; here is a small selection: Unfortunately, at present, there is no known causal or preventive therapy for most genetic dystrophic diseases. However, a lot of research is currently being done in the field of genetic engineering, and these therapies are currently only in the study phase.
- Ophthalmoscopy: often visible changes such as deposits in the ocular fundus are visible
- Electroretinography, which measures the electrical response of the retina to light stimuli
- Electrooculography, which measures changes in the electrical potential of the retina during eye movements.
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