Experiencing blurriness in one eye while the other remains clear can be concerning. While some instances stem from common, easily remedied issues, others may indicate conditions requiring prompt medical attention. This article explores various factors that can contribute to this phenomenon.
Everyday Causes of Blurry Vision in One Eye
Common, less severe conditions often cause blurry vision in one eye. Refractive errors, like astigmatism, prevent light from focusing correctly on the retina, causing distorted vision. Nearsightedness (myopia) blurs distant objects in one eye, while farsightedness (hyperopia) impacts near vision. Anisometropia occurs when each eye has a different refractive error, making one eye blurrier.
Dry eye syndrome, where eyes don’t produce enough tears or they evaporate too quickly, is another common cause. It can affect one eye more, especially with prolonged screen use or certain environmental conditions. Eye strain from extended reading or computer use can also cause temporary blurriness. Minor corneal abrasions (scratches) can cause pain and blurry vision, often from contact lens use, foreign objects, or rubbing. A foreign body in one eye can also cause irritation, watering, and blurred vision.
Serious Conditions That Can Cause Unilateral Blurriness
Sudden or persistent blurriness in one eye can signal a serious medical condition requiring immediate evaluation. Retinal detachment, where the retina pulls away from the back of the eye, causes sudden blurred vision, often with flashes of light, increased floaters (small specks or lines), or a shadow across the visual field. Without prompt treatment, this can lead to permanent vision loss.
Optic neuritis is inflammation of the optic nerve, which transmits visual information to the brain. It can cause blurred vision, dimness, or “washed-out” colors, often with pain, especially with eye movement. While often affecting one eye, it can occur in both. Acute angle-closure glaucoma involves a rapid pressure increase inside one eye. Symptoms include sudden blurry vision, severe eye pain, headache, nausea, vomiting, and rainbow-colored halos around lights; urgent medical intervention is needed to prevent permanent vision damage.
Other serious possibilities include stroke or transient ischemic attack (TIA), where blurry vision can occur if brain visual areas are affected by disrupted blood flow. These often present with neurological symptoms like weakness, numbness on one side, confusion, or difficulty speaking. Diabetic retinopathy, a diabetes complication, can also blur vision in one eye due to damaged retinal blood vessels. Wet macular degeneration involves abnormal blood vessel leakage in the macula, causing rapid central vision blurriness or distortion in one eye.
How Eye Professionals Diagnose and Treat
An eye care professional conducts a comprehensive examination to determine the cause of blurry vision in one eye. This begins with a detailed medical history and visual acuity assessment using eye charts. Diagnostic tools include a slit lamp exam for magnified eye structure views, and tonometry to measure intraocular pressure. A dilated eye exam, using drops to widen pupils, examines the retina and optic nerve. Visual field tests detect blind spots or reduced vision areas.
Treatment varies based on the diagnosed condition. For refractive errors, corrective lenses (glasses or contacts) are common, and LASIK may be an option. Dry eye syndrome is managed with artificial tears, specific eye drops, or therapies to improve tear production and reduce inflammation. Eye infections may require antibiotic, antiviral, or antifungal eye drops. Corneal abrasions often heal on their own, but antibiotic drops may prevent infection.
More serious conditions require specialized interventions. Retinal detachment may require laser treatment or surgery to reattach the retina and preserve vision. Acute angle-closure glaucoma is often treated with medications to quickly lower eye pressure, followed by laser or surgery to improve fluid drainage. Optic neuritis may be monitored, or corticosteroids prescribed to reduce inflammation and speed recovery. For conditions linked to systemic diseases like diabetes or stroke, managing the underlying health condition is important for eye health.
Maintaining Overall Eye Health
Proactive measures maintain healthy vision and reduce the risk of eye conditions. Regular comprehensive dilated eye exams are important; they allow professionals to detect early disease signs before symptoms appear. Understanding your family’s eye health history is also beneficial, as some conditions are genetic.
A healthy lifestyle supports eye well-being. Eating a balanced diet rich in fruits, vegetables, and omega-3 fatty fish provides nutrients like lutein and zeaxanthin for retinal health. Staying hydrated also prevents dry eyes. Protecting eyes from physical harm and environmental factors is important, including wearing protective eyewear during sports or tasks, and sunglasses that block 99-100% of UVA and UVB rays outdoors. Managing screen time with the 20-20-20 rule (looking 20 feet away for 20 seconds every 20 minutes) can reduce eye strain.