Mysterious pathology - eye heterochromia
Heterochromia of the eye is associated with impaired synthesispigment - melanin. People with this pathology have a different color of the iris. The hormone melanotropin, which is formed in the pituitary gland, enters the circulatory system and the cerebrospinal fluid, spread throughout the body, while regulating the biosynthesis of melanin in the body. After that, the molecule of the hormone is destroyed by peptide hydrolase cells. Therefore, if the biosynthesis of melanotropin and melanin is disturbed, iris heterochromy develops. It should be said that the concentration of melanin causes the color of the eyes. The color of the iris is closely related to the pigmentation of the skin and hair. There are two main types of iris - light (most often gray-blue with different shades) and brown (dark and light brown). It is established that absolutely identical irises of the same person do not exist in nature (meaning the localization and concentration of the pigment).
Heterochromia of the eye can also occur inthe result of depigmentation. Most experts are inclined to the version that true depigmentation is formed due to dystrophic processes in the iris of the eyes. An important factor in the development of eye heterochromia is heredity. In this case, one eye will be of the father's color, and the other of the mother's.
Do not forget that the eye's heterochromiadevelops due to a variety of diseases (iritis, glaucoma, choroiditis, siderosis, hemorrhages, etc.). At first glance, in this case, the difference in the color of irises is considered one of the brightest symptoms. However, a more detailed study establishes the underlying disease.
Heterochromia of the eye is divided into three types: secretory, complete, central. A characteristic feature of secretory heterochromia is that in one iris there are two colors. With complete heterochromia, the eyes of a man of different colors. With central heterochromia, the iris has more than two colors. Incidentally, one color is dominant, forming a ring around the pupil.
As a result of ophthalmic studies,It is noted that in people with a diagnosis of eye heterochromia, cataracts and cyclites are more often recorded. Heterochromia is equally common in both light-eyed blondes and dark-eyed brunettes. Some authors argue that this pathology is still more common in blue-eyed patients. In some cases, heterochromia in humans is observed from early childhood, in others - patients ascertain this fact only in adulthood. Heterochromia is often recorded in patients aged 20 to 45 years.
Heterochromia with a neurogenic etiology in allcases is accompanied by a normal function of the light eye, without any kind of deposits on the surface of the cornea, opacities of the vitreous and the lens. At a microscopic examination, a decrease in the concentration of stromal pigment is found in comparison with the other eye. In this case the pigmentation of the iris of the eye is uniform in all its parts. This type of heterochromia is characterized by the presence of sympathetic nerve paresis on the side where the discolored iris is located. The development of neurogenic heterochromia is associated with increased irritability of the cervical sympathetic node. Thus, this nerve affects the development of the iris and its pigment. These changes indicate a serious dysfunction in the apparatus of the nervous and vascular systems. Such a disease as albinism develops when the formation of retinal and mesodermal pigment is disturbed. Heterochromia of the eye is limited to a single mesodermal pigment of the iris. Another difference between albinism and heterochromia is that it does not give complications and is a familial, hereditary anomaly of pigment biosynthesis in the body.
