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Normal vision

Overview Risks Results

Refraction test

Alternative Names: Eye test - refraction; Vision test - refraction Normal Values: A normal value is 20/20 vision (perfect vision - able to read 3/8 inch letters at 20 feet). A small type size is also used to determine normal near vision. What abnormal results mean: Myopia (nearsightedness) Hyperopia (farsightedness) Astigmatism (asymmetrical cornea) Presbyopia (inability to focus on near objects that develops with age) Additional conditions under which the test may be performed: Corneal ulcers and infections Macular degeneration Retinal detachment Retinal vessel occlusion Retinitis pigmentosa Text Continues Below

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