Blurry vision in one eye, known as unilateral blurry vision, means one eye perceives images less clearly than the other. This can range from slight haziness to significant detail loss. The symptom can arise from various issues, from common conditions to more serious health concerns. A professional evaluation is important for accurate diagnosis.
Everyday Causes
Many instances of blurry vision in one eye stem from common conditions. Unevenly developed refractive errors, caused by an irregularly shaped cornea or lens, prevent light from focusing properly, causing distorted or blurry vision.
Dry eye syndrome is a frequent cause of blurriness in one eye. Insufficient or poor-quality tears make the ocular surface uneven, scattering light and causing blurred vision. Noticeable during prolonged activities like reading or computer use. Eye strain from overuse, such as extended screen time, can also temporarily affect one eye, causing transient blurring.
Contact lens issues are common culprits. A dirty, torn, or ill-fitting lens interferes with light, causing localized blurriness. Improper wear or cleaning can also lead to irritation or minor abrasions on the cornea, causing discomfort and blurriness.
Serious Conditions
While many causes of unilateral blurry vision are benign, some serious conditions require prompt medical attention. Retinal detachment is the retina pulling away. This leads to sudden blurry vision, with flashes of light or increased floaters. Untreated, it can cause permanent vision loss.
Optic neuritis involves inflammation of the optic nerve. This causes sudden vision loss in one eye, often with pain worsening with eye movement. It can indicate underlying neurological conditions like multiple sclerosis. Acute angle-closure glaucoma is another urgent cause, a sudden, severe increase in eye pressure. This leads to rapid blurry vision, intense eye pain, redness, headache, and nausea, requiring immediate intervention to prevent permanent damage.
Neurological events like a stroke or transient ischemic attack (TIA) can disrupt vision in one eye by affecting the brain’s visual processing centers or blood supply. Unilateral blurry vision often accompanies other neurological symptoms like sudden weakness, numbness on one side, difficulty speaking, or facial drooping. A corneal ulcer or infection, an open sore on the eye’s clear front surface, can also cause significant blurry vision, pain, redness, and light sensitivity. Cataracts, the clouding of the eye’s natural lens, can develop more significantly in one eye initially, leading to gradual haziness and worsening blurry vision.
When to Seek Professional Help
Recognizing when unilateral blurry vision warrants professional medical attention is important for vision. Any sudden, unexplained blurriness in one eye, especially without a clear cause, prompts immediate consultation. Urgency increases if accompanied by other symptoms.
Prompt evaluation is necessary for warning signs such as eye pain, redness, flashes of light, new or increased floaters, or double vision. Other symptoms like severe headache, nausea, sudden weakness or numbness on one side, or difficulty speaking alongside unilateral blurry vision, suggest a serious neurological event and require emergency medical attention. If blurry vision develops after eye injury or trauma, a professional examination is important to rule out damage. Persistent blurry vision that does not resolve or worsens also warrants a comprehensive eye examination.
During a comprehensive eye examination, an eye care professional assesses visual acuity, examines the eye’s external and internal structures using a slit lamp, and measures intraocular pressure. Pupils may be dilated for a thorough inspection of the retina and optic nerve. This evaluation helps pinpoint the underlying cause of blurry vision and guides treatment.
Addressing the Underlying Cause
Treatment for blurry vision in one eye depends directly on its underlying cause. For common refractive errors, corrective lenses (eyeglasses or contact lenses) refocus light on the retina. For dry eye syndrome, treatment involves lubricating eye drops to supplement tear production and stability. Lifestyle adjustments, such as screen breaks and humidifiers, help manage symptoms.
When an infection like a corneal ulcer is the cause, specific medications (antibiotic, antiviral, or antifungal eye drops) eliminate the pathogen and promote healing. For inflammatory conditions like optic neuritis, corticosteroids may reduce inflammation and restore vision, often administered orally or intravenously. In acute angle-closure glaucoma, medications rapidly lower eye pressure, and surgical procedures like a laser iridotomy may create a new drainage pathway.
More serious conditions often require surgical intervention. Retinal detachment necessitates surgical repair to reattach the retina and prevent permanent vision loss. Advanced cataracts are treated with cataract surgery to remove the clouded natural lens and replace it with an artificial intraocular lens. If unilateral blurry vision is a symptom of a systemic condition or neurological event like a stroke, treatment focuses on managing the underlying disease or injury, often involving a multidisciplinary medical approach.