There are different vision standards for different ages. For children before the age of 4 years, a visual acuity of 4.9 is normal and for adults, a visual acuity of 4.9 is not normal.
Visual acuity is the ability of the retina of the human eye to distinguish the minimum distance between two points. For adults, the normal visual acuity should be greater than 5.0. Visual acuity of 4.9 may be caused by refractive error, keratitis and other diseases, which need to be paid enough attention to make appropriate treatment for the cause to avoid further aggravation.
If a child’s visual acuity is 4.9 before the age of 4, this is a normal situation, with the normal development of the eye, the visual acuity can gradually rise.
If the standard visual acuity is 4.9, you should go to the hospital in time to improve the relevant examinations, such as funduscopic examination to exclude pathological factors.