Some Causes of Blurred Vision

Cause

Suggestive Findings

Diagnostic Approach

Opacification of eye structures

Cataracts

Gradual onset, often risk factors (eg, aging, corticosteroid use), loss of contrast, glare

Lens opacification on ophthalmoscopy or slit-lamp examination

Ophthalmic evaluation

Corneal opacification (eg, posttraumatic or postinfectious scarring)

Corneal abnormalities on slit-lamp examination

Ophthalmic evaluation

Disorders affecting the retina

Age-related macular degeneration

Sudden or gradual onset, central vision affected (central scotoma) without loss of peripheral vision, macular drusen or scarring, neovascular membrane

Fundoscopy

Infectious retinitis (eg, cytomegalovirus, Toxoplasma)

Usually HIV infection or other immunosuppressive disorder, often eye redness or pain, abnormal retinal findings

Fundoscopy

Studies as clinically indicated (eg, anti-Toxoplasma antibodies)

Retinitis pigmentosa

Primarily night blindness, gradual onset, pigmented retinal lesions

Fundoscopy

Specialized testing by ophthalmologist (eg, dark adaptation, electroretinography)

Retinopathy associated with systemic disorders (eg, hypertension, systemic lupus erythematosus, diabetes, Waldenström macroglobulinemia, multiple myeloma, or other disorders that could cause hyperviscosity syndrome)

Risk factors, retinal abnormalities detected during ophthalmoscopy (see table Interpretation of Some Red Flag Eye Findings)

Testing as indicated for clinically suspected disorders

Epiretinal membrane

Risk factors (eg, diabetic retinopathy, uveitis, retinal detachment or ocular injury)

Blurry or distorted vision (eg, straight lines appear wavy)

Fundoscopy

Optical coherence tomography

Macular hole

Blurry vision, initially central

Fundoscopy

Optical coherence tomography

Retinal vein occlusion

Risk factors (eg, hypertension, age, glaucoma)

Painless vision loss (usually sudden)

Sometimes, blurry vision

Fundoscopy

Sometimes, optical coherence tomography

Disorders affecting the optic nerve or neural pathways

Optic neuritis

Gradual onset unless due to multiple sclerosis (in which onset of optic neuritis is rapid)

Often unilateral or asymmetric

Pain with eye movement, direct pupillary light reflex decreased more than consensual (afferent pupillary defect), sometimes loss of optic disk margins and/or globe tenderness

Often MRI of brain and orbits to rule out multiple sclerosis

Disorders affecting focus

Refractive errors

Visual acuity varying with distance from objects, acuity corrected with refraction

Clinical refraction by an optometrist or ophthalmologist