Visual functions following recovery from non-arteritic central retinal artery occlusion

Visual acuity and other visual functions may improve following treatment of central retinal artery occlusion (CRAO). A prospective, noncomparative case series study was conducted to investigate patients' visual functions after treatment of non-arteritic CRAO.

Eight consecutive patients whose visual acuity improved following successful systematic treatment protocol for non-arteritic CRAO of less than 48 hours (one of them with patent cilioretinal artery) were evaluated for visual functions. The visual acuity in seven patients ranged from no light perception to counting fingers at 3 feet on presentation and improved to 20/100 to 20/20 following treatment. The visual tests included: blue-yellow (Farnsworth D-15) and green-red (pseudoisochromatic Ishihara color plates) color discrimination, contrast sensitivity, and visual fields. The patients were also evaluated for subjective daily function following treatment. All tests were also performed in the fellow uninvolved eye as a control.

The visual acuity following treatment improved from no light perception to counting fingers at 3 feet to an average of 20/65 (range, 20/20 to 20/100). Despite this improvement, six patients had dyschromatopsia to blue, green, or red whereas only two patients with a final visual acuity of 20/20 preserved their full color discrimination. All patients had decreased contrast sensitivity at mid-spatial frequency (6 cycles/min) or a more generalized decrease and visual field defects. All of the patients except one were satisfied with the visual outcome and daily function after treatment.

Despite improvement in visual acuity after treatment for CRAO, all patients had residual visual function abnormalities. These abnormalities may be attributed to partial recanalization, conversion of CRAO to multiple branch retinal artery occlusions, or different retinal susceptibility for ischemia.