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Action spectrum for photobleaching of human lenses by short wavelength visible irradiation.

Kessel L, Larsen M - PLoS ONE (2015)

Bottom Line: For a 75 year old lens an effect corresponding to elimination of 15 years or more of optical ageing was obtained.This study of the spectral characteristics and intensity needed to bleach the human lens with single-photon laser effects found an action-spectrum peak at 420 nm tailing gradually off toward longer wavelengths and more steeply toward shorter wavelengths.The results may be used to guide experiments with two-photon bleaching.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Glostrup Hospital, Glostrup, Denmark.

ABSTRACT

Purpose: Cataract is the world-leading cause of blindness. In search for a new treatment of cataract we have found that the yellow discolouration of aged human lenses can be photobleached using a non-invasive, infra-red, femtosecond laser treatment. These results were presented in an earlier PlosOne publication. The objective of the study was to characterize the single-photon photobleaching action spectrum of the aged human lens in vitro.

Methods: Ninety-one human donor lenses were irradiated with continuous wave laser light at 375, 405, 420, 445, 457 or 473 nm. Photobleaching was monitored by photography and transmission measurements.

Results: The action spectrum peaked at 420 nm followed by, in order of decreasing effect, 445, 457, 473, 405 and 375 nm. Younger and less absorbent lenses showed smaller changes than older and more absorbent lenses. There was a dose-dependent increase in lens transmission with increasing laser irradiation.

Conclusions: For a 75 year old lens an effect corresponding to elimination of 15 years or more of optical ageing was obtained. This study of the spectral characteristics and intensity needed to bleach the human lens with single-photon laser effects found an action-spectrum peak at 420 nm tailing gradually off toward longer wavelengths and more steeply toward shorter wavelengths. The results may be used to guide experiments with two-photon bleaching.

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Related in: MedlinePlus

Transmission increase as a function of pre-treatment light absorption.The relationship between transmission of blue light before irradiation with the increase in transmission (in %) after transmission for each of the 6 different irradiation wavelengths used in the experiments. To facilitate comparison between different lenses the effect is normalized to an irradiation dose of 1000 J/cm2 for all lenses.
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pone.0123732.g003: Transmission increase as a function of pre-treatment light absorption.The relationship between transmission of blue light before irradiation with the increase in transmission (in %) after transmission for each of the 6 different irradiation wavelengths used in the experiments. To facilitate comparison between different lenses the effect is normalized to an irradiation dose of 1000 J/cm2 for all lenses.

Mentions: The densely yellow lenses (lower blue light transmission) from older donors showed larger increases in blue light transmission after irradiation than the less yellow lenses of younger donors, see Fig 3.


Action spectrum for photobleaching of human lenses by short wavelength visible irradiation.

Kessel L, Larsen M - PLoS ONE (2015)

Transmission increase as a function of pre-treatment light absorption.The relationship between transmission of blue light before irradiation with the increase in transmission (in %) after transmission for each of the 6 different irradiation wavelengths used in the experiments. To facilitate comparison between different lenses the effect is normalized to an irradiation dose of 1000 J/cm2 for all lenses.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4401553&req=5

pone.0123732.g003: Transmission increase as a function of pre-treatment light absorption.The relationship between transmission of blue light before irradiation with the increase in transmission (in %) after transmission for each of the 6 different irradiation wavelengths used in the experiments. To facilitate comparison between different lenses the effect is normalized to an irradiation dose of 1000 J/cm2 for all lenses.
Mentions: The densely yellow lenses (lower blue light transmission) from older donors showed larger increases in blue light transmission after irradiation than the less yellow lenses of younger donors, see Fig 3.

Bottom Line: For a 75 year old lens an effect corresponding to elimination of 15 years or more of optical ageing was obtained.This study of the spectral characteristics and intensity needed to bleach the human lens with single-photon laser effects found an action-spectrum peak at 420 nm tailing gradually off toward longer wavelengths and more steeply toward shorter wavelengths.The results may be used to guide experiments with two-photon bleaching.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Glostrup Hospital, Glostrup, Denmark.

ABSTRACT

Purpose: Cataract is the world-leading cause of blindness. In search for a new treatment of cataract we have found that the yellow discolouration of aged human lenses can be photobleached using a non-invasive, infra-red, femtosecond laser treatment. These results were presented in an earlier PlosOne publication. The objective of the study was to characterize the single-photon photobleaching action spectrum of the aged human lens in vitro.

Methods: Ninety-one human donor lenses were irradiated with continuous wave laser light at 375, 405, 420, 445, 457 or 473 nm. Photobleaching was monitored by photography and transmission measurements.

Results: The action spectrum peaked at 420 nm followed by, in order of decreasing effect, 445, 457, 473, 405 and 375 nm. Younger and less absorbent lenses showed smaller changes than older and more absorbent lenses. There was a dose-dependent increase in lens transmission with increasing laser irradiation.

Conclusions: For a 75 year old lens an effect corresponding to elimination of 15 years or more of optical ageing was obtained. This study of the spectral characteristics and intensity needed to bleach the human lens with single-photon laser effects found an action-spectrum peak at 420 nm tailing gradually off toward longer wavelengths and more steeply toward shorter wavelengths. The results may be used to guide experiments with two-photon bleaching.

Show MeSH
Related in: MedlinePlus