A refraction test also called a vision test, is usually performed as a part of a routine eye examination. The purpose of this test is to determine if a person has a refractive error which would then mean the patient would need glasses or contact lenses.
Astigmatism (abnormally curved cornea causing blurred vision)
Presbyopia (inability to focus on near objects that develop with age)
Other conditions under which the test may be performed:
Corneal ulcers and infections
Loss of sharp vision due to macular degeneration
Retinal detachment (separation of the light-sensitive membrane (retina) in the back of the eye from its supporting layers)
Retinal vessel occlusion (blockage in a small artery that carries blood to the retina)
Retinitis pigmentosa (an inherited disorder of the retina)
There is an art to refraction and the optometrist will always answer the patient’s questions and as well as discuss their findings. Based on the results of the refraction test, they can determine the amount of myopia, hyperopia or astigmatism.
Children should have a refraction test yearly, starting at no later than 3 years of age. Healthy adults under age 60 who aren’t experiencing vision problems should have a refraction test every 2 years, while adults currently wearing prescription glasses or contact lenses or with a refractive error should have a refraction test every 1-2 years or when their vision changes which will allow the doctor to figure out what prescription is necessary as the eyes change. In the case of encountering any vision problems between exams, the eye doctor should be seen for another refraction test.
It is important that patients with diabetes have an eye examination every year. A number of eye conditions are associated with diabetes, such as diabetic retinopathy and glaucoma. According to the American Diabetes Association, people with diabetes are at a greater risk for blindness than other Americans.
Adults over 60 or who have a family history of glaucoma, should also have a refraction test every year. Glaucoma occurs when pressure builds up in the eye, damaging the retina and the optic nerve. Regular exams will help the eye doctor screen for glaucoma and other eye conditions associated with aging and when necessary, begin early treatment.