Blurred Vision

Blurred vision means objects appear out of focus, hazy, or unclear. While often caused by simple refractive errors requiring glasses, blurred vision can also indicate serious eye or neurological conditions that need prompt evaluation.

What Blurred Vision Feels Like

People with blurred vision often describe:

• Objects appearing fuzzy or out of focus at certain distances
• Difficulty reading small print or seeing detail
• Need to squint to see clearly
• Halos or glare around lights
• Gradual worsening over weeks, months, or years
• Sudden onset of blurring in one or both eyes
• Vision that fluctuates throughout the day
• Difficulty seeing in dim lighting
• Eye strain or fatigue after visual tasks

Common Causes

Refractive Errors (Most Common)

• Myopia (nearsightedness)—distant objects appear blurry
• Hyperopia (farsightedness)—close objects appear blurry
• Astigmatism—irregular cornea shape causing distortion
• Presbyopia—age-related difficulty focusing on near objects (typically after age 40)

Eye Conditions

• Cataracts—clouding of the eye's natural lens
• Dry eye syndrome—insufficient tear production
• Corneal problems—scarring, swelling, or irregularities
• Macular degeneration—deterioration of central retina
• Diabetic retinopathy—blood vessel damage from diabetes
• Glaucoma—optic nerve damage (usually affects peripheral vision first)

Neuro-Ophthalmologic Causes

• Optic neuritis—inflammation of the optic nerve
• Papilledema—swelling of the optic disc from increased brain pressure
• Optic neuropathy—damage to the optic nerve from various causes
• Multiple sclerosis—can cause episodes of blurred vision
• Brain tumors or lesions—affecting visual pathways
• Stroke—affecting visual processing areas

Other Medical Causes

• Uncontrolled diabetes causing lens swelling
• Medication side effects
• Migraine (temporary visual disturbance)
• High blood pressure

When to Seek Emergency Care

What You'll Be Asked in Clinic

Your doctor will ask detailed questions including:

About the symptoms:

• When did the blurring start—suddenly or gradually?
• Does it affect one eye, both eyes, or vision overall?
• Is it constant or does it come and go?
• Is near vision, distance vision, or both affected?
• Does it change with blinking or using eye drops?
• Any associated pain, headache, or other symptoms?

About your health:

• Do you wear glasses or contact lenses?
• When was your last eye exam?
• Do you have diabetes, high blood pressure, or autoimmune conditions?
• What medications are you taking?
• Any family history of eye disease?

How Blurred Vision Is Diagnosed

Comprehensive Eye Examination

• Visual acuity testing—reading the eye chart at various distances
• Refraction—determining if glasses would help
• Slit-lamp examination—detailed view of front eye structures
• Dilated fundus exam—viewing the retina and optic nerve
• Intraocular pressure—checking for glaucoma
• Pupil examination—assessing nerve function

Additional Testing May Include

• Optical coherence tomography (OCT)—detailed imaging of retina and optic nerve
• Visual field testing—mapping peripheral vision
• MRI of brain and orbits—if neurological cause suspected
• Blood tests—checking for diabetes, inflammation, or other conditions

Treatment Options

Treatment depends on the underlying cause:

For Refractive Errors

• Updated glasses or contact lens prescription
• Refractive surgery options (LASIK, PRK)

For Eye Conditions

• Cataract surgery when visually significant
• Treatment for dry eye (artificial tears, prescription drops)
• Management of retinal conditions
• Glaucoma treatment (drops, laser, or surgery)

For Neurological Causes

• IV steroids for optic neuritis
• Treatment of underlying condition (MS, tumor, etc.)
• Management of intracranial pressure if elevated
• Stroke treatment and prevention

For Medical Conditions

• Blood sugar control for diabetes
• Blood pressure management
• Adjusting medications that may cause blurring

Frequently Asked Questions

Can blurred vision go away on its own?

Sometimes. Blurring from fatigue, dry eye, or temporary conditions may resolve. However, new or persistent blurred vision should be evaluated to rule out treatable causes.

Does blurred vision mean I need glasses?

Not necessarily. While refractive errors are common, blurred vision can have many causes. A comprehensive eye exam will determine if glasses would help.

Can screen time cause permanent blurred vision?

Extended screen use causes eye strain and temporary blurring, but doesn't cause permanent damage. The "20-20-20 rule" helps: every 20 minutes, look at something 20 feet away for 20 seconds.

Why is my vision blurry only at certain times?

Fluctuating blur can indicate dry eye (worse later in day), blood sugar changes (diabetes), medication effects, or conditions like myasthenia gravis that worsen with fatigue.

Is blurred vision a sign of stroke?

It can be. Sudden vision changes, especially with other neurological symptoms, require immediate evaluation. However, most blurred vision has less serious causes.

How often should I get my eyes checked?

Adults should have comprehensive eye exams every 1-2 years, more frequently if you have diabetes, high blood pressure, or a family history of eye disease.

References