Blue Light Exposure and Uveal Melanoma

Abstract

It was with great interest that we read Shah et al’s article.1Shah C.P. Weis E. Lajous M. et al.Intermittent and chronic ultraviolet light exposure and uveal melanoma A meta-analysis.Ophthalmology. 2005; 112: 1599-1607Abstract Full Text Full Text PDF PubMed Scopus (136) Google Scholar The study was very well conducted and represented an interesting epidemiological examination of the potential risk factors involved in uveal melanoma. The major conclusion of the study was that, of all potential ultraviolet light exposures, the only one that significantly increased the risk of developing uveal melanoma was prolonged exposure to welding. However, we propose that the results suggest a minimal role for ultraviolet light in the development of uveal melanoma and invite further research regarding the specific reason why welding appears to increase the risk of developing uveal melanoma. Okuno et al2Okuno T. Saito H. Ojima J. Evaluation of blue-light hazards from various light sources.Dev Ophthalmol. 2002; 35: 104-112Crossref PubMed Scopus (46) Google Scholar evaluated various light sources for blue light hazard. Among these sources, arc welding was found to have extremely high effective radiance, with corresponding permissible exposure times of only 0.6 to 40 seconds, suggesting that viewing this light source is very hazardous to the retina. There is evidence suggesting that the major culprit is not ultraviolet light, but blue light exposure. Manning et al3Manning Jr, W.S. Greenlee P.G. Norton J.N. Ocular melanoma in a Long Evans rat.Contemp Top Lab Anim Sci. 2004; 43: 44-46PubMed Google Scholar induced an ocular melanoma in a rat exposed to half-amplitude band pass fluorescent blue light (434–475 nm). We did an in vitro study to investigate the effect of blue light on the proliferation rates of melanoma cell lines. Cells were exposed to blue light with and without the presence of ultraviolet light–absorbing or blue light–filtering intraocular lenses (IOLs). The proliferation rate of the cells relative to a control was then assessed (Fig 1 [available at http://aaojournal.org]). Cells exposed to blue light showed a significant increase in proliferation. Those exposed to blue light through a standard IOL showed a smaller increase in proliferation, whereas those exposed with a blue light–filtering IOL showed no increase in proliferation in 3 of the 4 cell lines. Our data provide evidence regarding the role of blue light in the oncogenesis of uveal melanoma. Blue Light Exposure and Uveal Melanoma: Author ReplyOphthalmologyVol. 113Issue 6PreviewDr Fernandes et al present data that suggest blue light is involved in the proliferation of certain human uveal melanoma cell lines, concluding that blue light may have a role in the oncogenesis of uveal melanoma. Although these preliminary data are interesting, the relationship between blue light and uveal melanoma remains inconclusive. Full-Text PDF