Experiencing a sudden blurring or haziness in the vision of just one eye can be a concerning symptom. This change, known as monocular blurry vision, indicates something specific is affecting that eye or its visual pathway. This article explores various potential reasons behind such a sudden change in vision.
Common and Less Serious Causes
Sudden blurry vision in one eye can stem from less serious issues that are often temporary or easily resolved. Eye strain, for example, can occur after prolonged focus on digital screens or close-up tasks. This overuse can temporarily fatigue the eye’s focusing muscles, leading to a transient blur in one eye.
Dry eye is another frequent cause, occurring when the eye doesn’t produce enough quality tears to keep its surface adequately lubricated. An insufficient tear film can disrupt the smooth surface of the cornea, causing light to scatter and resulting in blurry vision that might improve with blinking. This condition can also lead to discomfort, redness, and a gritty sensation.
Certain medications can also induce temporary vision changes as a side effect. Drugs like antihistamines, decongestants, or some blood pressure medications can reduce tear production, contributing to dry eye and blurriness. If you suspect a medication is affecting your vision, consult your healthcare provider.
A foreign body, like a speck of dust or an eyelash, on the eye’s surface can cause sudden blurriness and irritation. The eye’s natural response to clear the object, such as increased tearing, might temporarily worsen the blur. Corneal abrasions, which are scratches on the clear outer layer of the eye, can also cause pain and blurry vision.
Serious Conditions Requiring Prompt Attention
Sudden blurry vision in one eye can also indicate a serious underlying condition requiring immediate medical evaluation. Retinal detachment is a severe condition where the retina, the light-sensitive tissue at the back of the eye, pulls away from its supporting layers. This separation can lead to sudden blurry vision, often described as a shadow or curtain moving across the visual field, accompanied by flashes of light or new floaters.
Optic neuritis involves inflammation of the optic nerve, which transmits visual information from the eye to the brain. This inflammation can lead to sudden blurred vision, often accompanied by pain with eye movement and diminished color perception. It may occur independently or as a symptom of other neurological conditions.
A stroke or transient ischemic attack (TIA), sometimes called a “mini-stroke,” can also manifest as sudden blurry vision in one eye. These conditions occur when blood flow to a part of the brain, including vision areas, is interrupted or significantly reduced. Vision changes from a stroke or TIA are often accompanied by other neurological symptoms like sudden weakness or numbness on one side of the body, difficulty speaking, or confusion.
Acute angle-closure glaucoma is an ocular emergency characterized by a rapid increase in pressure inside the eye. This pressure spike can damage the optic nerve, leading to blurry vision, severe eye pain, headache, nausea, and seeing halos around lights. Prompt treatment is necessary to prevent permanent vision loss.
Wet age-related macular degeneration (AMD), a severe form of AMD, can cause sudden blurriness in central vision. This occurs when abnormal blood vessels grow under the retina and leak fluid or blood, disrupting the macula’s function. Symptoms may include distorted vision, where straight lines appear wavy, and a blurry or blind spot in the central visual field.
When to Seek Medical Help
The sudden onset of blurry vision in one eye should always be taken seriously, as it can be a medical emergency. Prompt medical attention is advised, especially if the vision change is accompanied by other symptoms.
Specific accompanying symptoms that warrant urgent medical evaluation include eye pain, headaches, flashes of light, or an increase in floaters. A sudden loss of peripheral vision or the sensation of a “curtain” or shadow moving across your vision are also red flags. Other concerning signs are double vision, recent head trauma, or any neurological symptoms such as weakness, numbness, difficulty speaking, or balance issues.
Even if the blurry vision is temporary, seeking medical help is crucial. Conditions like a transient ischemic attack (TIA) can cause fleeting vision loss but indicate a risk for future, more severe events. Consulting an eye care professional ensures a proper diagnosis and timely intervention, which can be essential for preserving vision and addressing any underlying health issues.