Differential Diagnosis for Blurred Vision

Refractive Causes

The American Academy of Ophthalmology suggests that myopia (nearsightedness) is a common cause of blurred vision, characterized by difficulty seeing distant objects clearly, with near vision typically preserved 1, 2
Hyperopia (farsightedness) is another refractive error that can cause blurred vision, particularly with near vision, though distance vision may also be affected depending on accommodative ability 1, 2, 3
Astigmatism can cause blurred or distorted vision at all distances due to irregular corneal or lenticular curvature 1, 2
Presbyopia is an age-related loss of near vision beginning around age 40-45 years due to decreased lens flexibility and accommodation 4, 3

Dry eye syndrome can cause intermittent blurred vision, often worse upon waking and improving later in the day, with symptoms including burning and foreign body sensation 5
Tear film instability in dry eye syndrome disrupts the optical surface, leading to blurred vision 5
Corneal edema can cause blurred vision with diurnal variation, worse upon waking, and clearer later in the day due to evaporation 6

Cataract can cause gradual progressive blurred vision, glare disability, and reduced contrast sensitivity 7
Posterior capsule opacification can occur after cataract surgery, causing gradual vision decline, with an incidence of 4-7% in various studies 7

Optic neuritis can cause painful eye movements, decreased color vision, and relative afferent pupillary defect 2
Glaucoma can cause peripheral vision loss initially, but can affect central vision in advanced disease 2

Cortical visual impairment can cause bilateral vision loss with normal pupillary responses and fundus examination 2
Migraine with aura can cause transient visual disturbances with characteristic fortification spectra 2

Topical corticosteroids can cause elevated IOP leading to corneal edema 6
Systemic medications can affect accommodation, tear production, or cause macular toxicity 2, 5

The American Academy of Ophthalmology recommends a systematic evaluation of refractive, ocular surface, media, and posterior segment pathology to diagnose the cause of blurred vision 1, 2
A pinhole test can be used to rapidly distinguish optical refractive causes from other pathology, with improvement suggesting refractive error as the primary etiology 2
A slit-lamp examination and dilated fundus exam can be used to evaluate the anterior and posterior segments of the eye 2
The timing of symptoms, such as worse vision upon waking, can suggest corneal edema or dry eye 6, 5
Glare disability with relatively preserved acuity can suggest cataract 7