Abstract
Purpose: :
Recent studies have suggested that rate of progression of Age-Related Maculopathy (ARM) is likely to increase following cataract surgery. It has been proposed that excess exposure to "blue or violet-light" following cataract surgery may result in accelerated progression of ARM. Our group performed an observational pilot study to test this hypothesis by implanting a "blue-light" filtering IOL (Alcon Acrysof SN60WF) and a standard "UV" filtering IOL (Alcon Acrysof SA60AT) in each eye of patients with early ARM to determine the rate of progression in each eye. We also sought to assess the impact of this "blue-light" filtering IOL on visual function in patients with ARM in dim light.
Methods: :
Both eyes of 7 patients with stage 2a-3 ARM were implanted with identical hydrophobic acrylic IOLs; one eye with a SN60WF and the other with the SA60AT within 6 weeks. Progression of ARM was assessed using Rotterdam AMD grading scale and total drusen area count. Visual function in mesopic conditions was assessed using Vector Vision CSV 1000 EDTRS charts. Macular pigment was measured post operatively at 30 months using Raman spectroscopy.
Results: :
Seven patients were recruited 5 were suitable for analysis. The mean follow-up period was 33 months. Retinal imaging was available pre and post surgery at 1, 18 and 30 months. All 5 patients showed progression of ARM in both eyes, 4 patients showed more progression in the eye with SN60WF. The 5th showed more progression in the eye with the SA60AT between visits 1 and 2 but between visits 2 and 3 showed some regression. Macular pigment measurement at 30 months in 4 patients revealed that in all 4 of them, there is a difference between both eyes with the eye being implanted with SA60AT having the higher macular pigment density. Visual function assessment showed that contrast sensitivity and colour vision were reduced in eyes implanted with the SN60WF lens. Statistical tests have not been applied to these figures due to small number of patients.
Conclusions: :
Although the numbers are small, our data suggests that blue filtering lenses are not protective for ARM progression and may reduce visual function in patients with ARM.
Keywords: age-related macular degeneration • intraocular lens • visual acuity