The impact of age-related cataracts on colour perception, postoperative recovery and related spectra derived from test of hue perception

BackgroundCataract patients were always excluded from studies on ageing of colour vision; thus, effect of age-related cataracts on deterioration of colour perception has not been analysed. In present study, impacts of age-related cataracts on colour discrimination, postoperative recovery and related spectra were investigated.MethodsIn this cohort study, thirty age-related cataract patients scheduled for binocular surgery and 30 elderly volunteers were enrolled. Colour discrimination under photopic (1000lx) and mesopic (40lx) conditions was evaluated with Farnsworth-Munsell 100-hue test. The total error score (TES) and partial error score (PES) were calculated.ResultsPreoperatively, the TES in the patient group was 129.759.5 at 1000lx and 194.6 +/- 74.5 at 40lx, exhibiting worse discrimination than the volunteer group (TES1000lux=71.5 +/- 37.5 and TES40lux=113.1 +/- 38.8, p0.001). Inferior perception were detected in the yellow to green-yellow (Y-GY), green-yellow to green (GY-G), green to blue-green (G-BG) and blue-green to blue (BG-B) colour bands (p0.003), corresponding to the 470nm-580nm range of the visible light spectrum. Under mesopic conditions, the impact expanded to all colour bands except for yellow-red to yellow (YR-Y). Postoperatively, the TES in the patient group were 80.4 +/- 62.4 at 1000lx and 112.0 +/- 85.2 at 40lx, which were lower than those of the preoperative phase (p0.001) but similar to those of the volunteer group (p0.505). Postoperative improvement occurred in the Y-GY, GY-G and G-BG colour bands (490nm to 580nm) at 1000lx (p0.001) and shifted to the Y-GY, GY-G, G-BG and BG-B colour bands (470nm to 580nm) at 40lx (p0.001). Deterioration of hue perception for decrement of illumination was detected in the red to yellow-red (R-YR), Y-GY, G-BG, BG-B, blue to purple-blue (B-PB) and red-purple to red (RP-R) colour bands (450nm to 500nm) in the volunteer group (p0.002) and the R-YR, G-BG, BG-B, B-PB, PB-P and red-purple to red (RP-R) colour bands (from the short-wavelength end to 500nm) in the patient group preoperatively (p0.001).Conclusions Phacoemulsification could effectively rebuild colour perception in patients with age-related cataract. The postoperative benefits were most significant in colour bands corresponding with spectrum from 470nm to 580nm.