Differential Diagnosis of Glare in the Eye

Posterior subcapsular cataracts cause the most severe glare symptoms, particularly in bright light conditions, with near vision typically more affected than distance vision due to miosis with accommodation 1
Cortical cataracts commonly produce glare symptoms, appearing as opaque spokes or oil droplets, with patients frequently complaining of glare when driving at night 1
Nuclear cataracts primarily affect distance vision and progress slowly, causing less prominent glare compared to PSC or cortical types 1
Glare testing is particularly useful for evaluating cortical and posterior subcapsular cataracts, which significantly impact vision in bright light conditions 2, 1

Acute Angle-Closure Glaucoma

Acute angle-closure crisis presents with halos around lights, blurred vision, eye pain, headache, eye redness, and potentially nausea and vomiting 3
Pressure-induced corneal edema is experienced as blurred vision and halos around lights, requiring immediate ophthalmologic evaluation to prevent permanent vision loss 3
Immediate medical therapy to lower IOP is required, with definitive treatment via laser peripheral iridotomy once IOP is controlled 3

History of LASIK or other refractive surgery should prompt evaluation for irregular astigmatism or corneal ectasia 3
Smaller treatment-zone sizes may increase the likelihood of visually disturbing halo formation in low-light conditions 3
Higher-order aberrations cannot be fully corrected by spherocylindrical lenses and may contribute to glare symptoms 4

Irregular corneal astigmatism from keratoconus, corneal ectasias, corneal epithelial basement membrane dystrophies, stromal dystrophies, and corneal scarring cause glare 4
Postsurgical corneas may develop irregular astigmatism contributing to glare symptoms 4
Ocular surface disease can cause significant reduction in visual acuity with glare testing, requiring correlation with slit-lamp biomicroscopy findings 2

Emergency evaluation is required in the presence of pain, redness, nausea, or sudden vision loss, which suggests acute angle-closure 3
Key history elements include duration and progression of symptoms, history of refractive surgery, and family history of glaucoma 3
Physical examination should focus on visual acuity assessment, pupil examination, slit-lamp examination for corneal edema, lens opacities, and anterior chamber depth 3
Gonioscopy is essential to exclude angle closure or secondary causes of IOP elevation 5

Contrast sensitivity testing may reveal functional vision loss not detected by standard visual acuity testing alone 2, 1
Glare testing determines the degree of visual impairment in the presence of light scatter, particularly useful when visual acuity appears normal in darkened examination rooms but drops significantly with glare source 2