We thank Drs Mainster and Turner for their instructive comments regarding our article. Drs Mainster and Turner highlighted the following introductory statement: “As a result of exposure to ultraviolet-A and blue light, the risk of development or progression of age-related macular degeneration is known to be increased.”
The aim of our paper is to show the adverse effect of yellow intraocular lenses on short-wavelength automated perimetry, rather than to show the relationship between cataract surgery and age-related macular degeneration (AMD). Our comment in the introductory paragraph regarding exposure to blue light and the risk of development of AMD was intended to explain the background of the usage of yellow-tinted intraocular lenses. Whether or not the risk of development or progression of AMD is higher in pseudophakic or aphakic eyes is an unresolved clinical question and a topic of much ongoing debate. We thus agree with the comment by Drs Mainster and Turner that the above sentence was misleading. There is in fact not enough scientific evidence for the claim.
Basically, cataract extraction leads to a dramatic increase in the ocular transmittance of radiation. Thus, concerns have emerged that cataract surgery may be associated with an increased risk of development or progression of AMD. The link between cataract surgery and AMD has been investigated in many epidemiologic studies, with inconsistent findings. Drs Mainster and Turner mentioned that intraocular lens chromophores cannot prevent AMD because cataract surgery does not cause it. However, while the majority of epidemiologic studies do not support the phototoxicity-AMD hypothesis, there are still well-designed epidemiologic studies that have supported the possible role of cataract surgery in triggering advanced AMD. Fraser-Bell and associates reported a positive association between cataract extraction and AMD in their recent well-designed population-based, cross-sectional study with references to 3 large population-based epidemiologic studies. The Beaver Dam Eye Study (BDES) and Blue Mountains Eye Study (BMES) indicated an association of AMD with cataract surgery. The Age-Related Eye Disease Study (AREDS), which was cited in the review article by Mainster and Turner, did not find an association between cataract surgery and AMD. It was also cited in Fraser-Bell and associates’ article in reference to the relationship between cataract extraction and AMD still being unclear.
Obviously, further investigation should continue to prove or deny the phototoxicity-AMD hypothesis. We appreciate Dr Mainster’s and Dr Turner’s interest and thank them for giving us an opportunity to consider an important point that we had not fully considered.