Eye Exam vs. Vision Test
In some provinces, a number of optical stores offer sight tests, or vision tests, which use automated machinery. However, a sight test is not a proper comprehensive eye exam. Only a trained and licensed professional doctor of optometry can perform a comprehensive eye exam. Optometrists have the education, training and knowledge to examine, diagnose, treat, manage and help prevent diseases and disorders affecting the visual system, the eye and related structures, as well as check an individual’s prescription and prescribe eye wear. In many provinces, doctors of optometry can also prescribe medications to treat certain eye conditions, such as infections, inflammations, allergies and injuries.
A sight test prescribes a refraction to determine the lens power required for correction of vision by relying on a combination of computerized tests using automated equipment. The comprehensiveness and accuracy of these automated sight tests is limited. Eye muscle coordination is unaccounted for, and eye fixation and alignment, pupil size, corneal or lens irregularities, patient movement and attention, and something called instrument myopia can influence the test results. This last problem is created by the eye’s tendency to over-focus when looking through a machine such as this. This can result in an inaccurate measurement of refraction.
An eye exam performed by a doctor of optometry looks at the entire eye health and visual system, as well as your prescription, and is an important part of preventative health care. Think of an eye exam as a physical for your eyes. Eye exams can detect eye diseases and disorders such as glaucoma, cataracts, retinal detachments and macular degeneration, and other health problems such as diabetes, high blood pressure and brain tumors.