Eyeshot is part of space which can be seen through the eyes at an immobile head and immobile eyes. There are diseases of the eye, in which in a certain place the sharpness of sight is violated, dark patches, urgent scotomas, appear suddenly. A scotoma is a small area in sight, in which sight is hyposthenic or absents fully. Usually from every quarter this area is surrounded the areas of normal vision. The eyots of complete loss of eyesight in the areas of eyeshot are named absolute scotomas. A relative scotoma is a small spot which sight is saved in, but it is considerably mionectic. Also color scotomas can arise up, when a patient does not see certain colors.
- Area, in which sight is reduced or completely absent, appears in the field of view.
Eyeball from within is covered a retina, the specialized nervous completions, which are located in it, are registered by the images of the outer world, passing to their visual nerve, from where information enters farther cerebrum. For the people of superannuated a retina is predispositioned to the breaks. Thus, there is a danger, that at rapid motion of eyes a vitreous body, filling greater part of cavity of eyeball, can move a retina, which can result in its break. For a patient a spot, closing an image, appears before eyes, i.e. scotoma. This disease often shows up for elderly people, sufferings myopia.
Removing layer by layer of retina can happen at saccharine diabetes or hypertensive illness. There is a large danger of removing layer by layer of retina and narrowing of eyeshot at eye traumas. The small narrowing of eyeshot in form ring – the characteristic symptom of the early stage of glaucoma. At color scotomas on green and red colors it is possible to suppose the presence of disease of visual nerve. For example, if a tumor presses on a visual nerve, the site of damage can be defined in grain violations of eyeshot. There is violation of yellow and green color sight at the disease of retina.
At removing layer by layer of retina an operation is usually conducted. Treatment of breaks of retina is conducted by a laser. If the cause of violation of eyeshot is a prelum of visual nerve a brain tumor (a hemianopsia – a fall of half of eyeshot, arising up at brain hemorrhage, traumas, tumors), treatment of violation of eyeshot becomes second-rate: it is important to remove a tumor.
At any trauma of eye it is necessary necessarily to appeal to the doctor .
Usually violations of eyeshot are insignificant, and it is sufficiently difficult to notice them. However at the least suspicion on narrowing of eyeshot or at appearance of scotomas, it is necessary to appeal to the ophthalmologist.
An ophthalmologist will conduct certain researches (perimetry – research of eyeshot). He or she can ask a patient to look at the nose and will take interest here, whether a patient sees motion of his finger near-by the supposed border of eyeshot.