Peripheral vision

Today's article will be devoted to vision and his work. We will note how the visual apparatus works, what peripheral vision is and what angle of view is accessible to the human body.

One of the functions of the visual apparatus is peripheral vision. Peripheral parts of the retina are responsible for it . The main indicator of its productivity is the angle of the person's view. It includes that part of the space that human vision covers while fixing a fixed view of the object. The main function of peripheral vision is the orientation in space.

The field of view index has specific values determined by the retina boundary. The eye reacts to a white color within the following limits: the outside is 90º, the outside is 70º, the inside 55º, the inside 55º, the inside 50º, the bottom 65º, the down 90º. The "fallout" of its individual parts is called cattle. In the area of the temporal field of vision there is a physiological scotoma - the so-called "blind spot". Natural is the presence of angioscic - ribbon-like "fallout" in the field of vision, associated with the presence of massive reticular vessels that close the photoreceptor cells. Their presence only slightly worsens peripheral vision And is considered the norm.

The scotomas are absolute, with a complete "fallout" of the site, and relative - with noticeable impairments of visual function in the surveyed interval. In turn, these two types are divided into positive and negative scotomas. Positive can be detected independently: they are visible as black spots in the field of vision, which indicates the damage to the retina. Negative scotomas are not subject to independent detection and appear due to damage to the conducting paths. They are usually found during examination. There are also ciliary scotomas. As a rule, their appearance does not obey any system and is completely spontaneous. If a patient with closed eyes observes zigzag-like colored lines that extend beyond peripheral vision, he has spasms of cerebral vessels. To stop this process and improve the situation, doctors recommend immediately taking antispasmodics.

The location of the scotoma can be classified as follows:

• Peripheral;
• Paracentral;
• The central ones.

Next, we give a list of problems with vision, which contribute to the deterioration of peripheral visual perception.

The narrowing of the field of view from all sides to 5 - 10 degrees is a consequence of nerve damage and retinal dystrophy. This phenomenon is called concentric narrowing of the field of view. As a rule, in such a situation a person still sees and can even read, but the ability to independently navigate in space disappears completely and visual perception deteriorates significantly.

In the event that the patient has lost symmetrical viewpoints, it is worthwhile to contact specialists for a thorough examination. Such symptoms often indicate the presence of a patient's tumors, hemorrhages and other serious diseases. At the initial stages of tumors and inflammations, only a part of the vision may be lost, that is, approximately one-fourth of the field of vision disappears. With retinal pathologies, vision can disappear in different areas. For example, with glaucoma, the field of vision from the nose narrows.

Analyzing the nature of the limitation of the field of vision, an experienced specialist can determine the localization of the lesion in various departments of the visual pathways, as well as the degree of degenerative lesion, the stage of glaucoma and other parameters.