Color blindness is a hereditary eye defect resulting from an abnormal structure of the retina. It affects almost exclusively men. It is commonly believed that color blindness does not see any colors at all, and color blindness is called color blindness. Meanwhile, color-blinders most often do not recognize the color green, or confuse it with the color red.

Color blindnessisa visual defectnamed after the English chemist and physicist John D alton, who noticed that he perceived certain colors differently than other people: he sees green objects as red. D alton described his visual impairment, but none of his contemporaries could explain why. Only the research carried out in 1994 at the London Institute of Ophthalmology showed that the disorders in distinguishing colors were caused by an incorrect structure of the retina, i.e. it did not contain one of the three photoreceptors responsible for the vision of red color.

Color blindness: reasons

Color blindness is, in most cases, an inherited hereditary disease. The gene responsible for the development of color blindness is located on the X chromosome. In the genetic code, males have only one X (XY) chromosome, while females have two (XX). Therefore, it is men who more often have problems with recognizing the color green and red. It is estimated that one in eight men may have this defect, while one in a hundred women is color-blind. It happens that color blindness is diagnosed in a child, and parents are only carriers of a disease that does not manifest themselves in them. Occasionally, color blindness can occur after an accident or head injury, when the optic nerve or retina is damaged. It can also be a side effect of certain drugs and chemicals, as well as chronic diseases such as diabetes. In these situations, we deal with acquired color blindness.

Types of color blindness

Sometimes the symptoms of the disease are mild and the patient does not realize that they are color blind. There are several types of color blindness that can cause color vision problems. The most common is dichromatism (when one of the photoreceptors is missing). Such a person does not completely recognize red or green. With trichromatism, there are differences in the sensitivity of the suppositories in the retina, co within turn, it reduces the saturation of one of the colors. The most severe variety, fortunately occurring very rarely, is monochromatism. Apart from white and black, the color-blind person does not distinguish any other color.

Color blindness: diagnosis

Sometimes the lack of color distinction can be noticed while playing with the child. Usually, however, color blindness is diagnosed during periodic ophthalmological examinations, as color blind patients generally have no other vision problems. A special graphic test is used for diagnosis. Most often they are the so-called the tablets of Ishihara. They represent numbers that consist of small circles of a given color on a background made up of circles of a different color. Each eye is examined separately. A he althy person will read the numbers correctly, a color blind person will not. When more precise examinations are needed, an instrument called an anomaloscope is used. The patient's task is to compare two colors.

Color blindness: treatment

There is no method that can completely cure congenital color blindness. Color disturbances can be corrected with glasses equipped with special corrective lenses. They make it possible to see red, green and derivatives. This possibility only applies to people with partial color blindness. Recently, the medical world circulated information about the possibility of treating color blindness using gene therapy, and the ability to see was restored in monkeys. Perhaps the treatment of color blindness with the help of genes will become the future of ophthalmology.

Important

Color blindness is not life-threatening, but it is important to detect the disease, as it prevents the performance of some professions, e.g. driver, pilot, train driver. Color blinders can be especially dangerous in traffic. Persons with good vision from a distance will notice the light of the beacons. In a color-blind man, these colors merge into one, hence there are accidents caused by running into the tracks despite the red light of the semaphore. Another problem is that a color-blind person may not notice blood in his stool or urine, which is a symptom of many serious diseases.

Category:

Eye diseases and vision disorders