The ability to see is a very complex, multi-step process that does not involve all brain structures. Seeing a certain volume, color, shape, but also to understand what exactly we see, what it is used for, how it moves, how to pick it up, etc. Therefore, violations, even at first glance the most insignificant, change the quality of our life, and sometimes deprive us of many opportunities. Visual impairment can be as acute. With an acute, sudden decrease in vision, a spot, veil, cloud, blackness appears in front of the eye, the acuity and contrast of vision change.