Vision appraisal comprises of tests and examinations detecting defects in the functionalities of the visual system and evaluating the eyes’ ability to perceive things and their details efficiently. Vision appraisals may also include testing the ability of the eyes in perceiving and distinguishing colors. They include tests such as visual acuity, refraction, visual field tests, and color vision tests.
An acuity test is usually held to determine the problems of farsightedness or nearsightedness and decide whether the patient would require glasses or contact lenses for vision improvement. This test is often performed after the patient suffers from any kind of eye injury or after the renewal of a driver’s license and to fulfill specific employment requirements. The frequency of the routine checks may vary according to the age of the individuals. Refraction tests usually follow vision acuity tests and help in determining whether the patient requires glasses or contact lenses and if so, they help in prescribing the right ones.
Visual field tests are mostly performed for screening gaps and defects of vision loss in the area of the vision field, and for detecting eye diseases such as glaucoma and macular degeneration, which causes gaps in the visual field. These tests can also be a part of neurological examinations that follow head injuries or strokes that cause a reduced rate of the blood flow to the brain.
Color vision tests may be a part of the routine eye check ups or to diagnose color blindness. It can also be part of the screening process for specific employments such as jobs related to driving, military or electronics. Vision appraisals or tests do not require any specific preparations. Patients undergoing vision treatments are advised to carry their prescriptions including their glasses or contact lenses if used. These tests are usually performed by ophthalmologists, optometrists or other trained professionals and the interval of the tests may vary depending on the individual’s visual capacity and problems.