Abstract
Abstract: :
Purpose: To determine the effect of a coated yellow filter on contrast threshold with and without glare under mesopic conditions in eyes having uncomplicated excimer laser in situ keratomileusis (LASIK) for myopia. Methods: The mesopic contrast threshold was measured in the absence or presence of glare using the Mesoptometer II test in 35 right eyes of adult subjects (mean age 36.9 ± 7.4) after 12 and 60 months of LASIK surgery, with and without coated yellow filter (482 nm cut-off), and 30 emmetropic eyes of adult subjects (mean age 35.2 ± 4.7) as control group. Results: Lasik group didn’t discriminate the lowest contrast threshold without glare, however a 73.33% of control group reached it. When the yellow filter was interposed in the lasik group the proportion of subjects who discriminated the lowest contrast threshold increased by 20%. With glare, 11.43% of lasik group’s subjects reached the lowest contrast threshold increasing by 14.29% with the yellow filter, and being of 46.67% in the control group. With the yellow filter, the contrast threshold mean improved with glare (p = 0.0479) and without glare (p = 0.00012) respect the lasik group without filter. Moreover, contrast threshold differences among control and lasik group were statistically significant, obtaining the control group the best contrast thresholds with glare (p = 0.01) and without glare (p = 0.01). Conclusions: The effect of yellow filter without residual reflections had a positive influence on the mesopic contrast perception of eyes having uncomplicated excimer laser in situ keratomileusis (LASIK) for myopia.
Keywords: contrast sensitivity • imaging/image analysis: clinical • physiological optics