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Blurred Vision
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Blurred Vision

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Blurred vision is the most common ophthalmologic complaint and can mean general visual dimming (which in an extreme form becomes blindness), reduced field of vision, or distortion of vision.

The most common causes are refractive error, cataracts, glaucoma, diabetic retinopathy, and age-related macular degeneration; less common causes include retinal detachment, optic neuritis or neuropathy, stroke, retinal vascular occlusion, uveitis, and keratitis.

It is important to determine if blurred vision affects one or both eyes, if pupils are normal or an afferent pupillary defect (APD) is present, and if corrective lenses (or pinhole visual acuity testing) improves vision. Monocular blurring with an APD suggests optic neuritis, neuropathy, or atrophy. Binocular blurring with improvement of visual acuity with pinhole testing suggests refractive error. Other variants (monocular blurring with normal pupils, binocular blurring without pinhole improvement) suggest other causes.

Follow-up testing may include tonometry (for glaucoma), fluorescein angiography (for age-related macular degeneration, branch retinal vein occlusion/central retinal vein occlusion, diabetic retinopathy), and MRI (for optic neuritis, stroke).

Most patients have some measure of refractive error and respond to corrective lenses, but other underlying causes must also be treated.

Last full review/revision November 2005

Content last modified November 2005

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