Open Access Open Badges Study protocol

Low-level night-time light therapy for age-related macular degeneration (ALight): study protocol for a randomized controlled trial

Claire McKeague1, Tom H Margrain1, Clare Bailey2 and Alison M Binns13*

Author Affiliations

1 School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4 LU, UK

2 Bristol Eye Hospital, Lower Maudlin Street, Bristol BS1 2LX, UK

3 Division of Optometry and Visual Science, School of Health Sciences, City University, London EC1V 0HB, UK

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Trials 2014, 15:246  doi:10.1186/1745-6215-15-246

Published: 24 June 2014



Age-related macular degeneration (AMD) is the leading cause of blindness among older adults in the developed world. The only treatments currently available, such as ranibizumab injections, are for neovascular AMD, which accounts for only 10 to 15% of people with the condition. Hypoxia has been implicated as one of the primary causes of AMD, and is most acute at night when the retina is most metabolically active. By increasing light levels at night, the metabolic requirements of the retina and hence the hypoxia will be considerably reduced. This trial seeks to determine whether wearing a light mask that emits a dim, green light during the night can prevent the progression of early AMD.


ALight is a Phase I/IIa, multicentre, randomized controlled trial. Sixty participants (55 to 88 years old) with early AMD in one eye and neovascular AMD (nAMD) in the fellow eye will be recruited from nAMD clinics. They will be randomized (in the ratio 1:1), either to receive the intervention or to be in the untreated control group, stratified according to risk of disease progression. An additional 40 participants with healthy retinal appearance, or early AMD only, will be recruited for a baseline cross-sectional analysis. The intervention is an eye mask that emits a dim green light to illuminate the retina through closed eyelids at night. This is designed to reduce the metabolic activity of the retina, thereby reducing the potential risk of hypoxia. Participants will wear the mask every night for 12 months. Ophthalmologists carrying out monthly assessments will be masked to the treatment group, but participants will be aware of their treatment group. The primary outcome measure is the proportion of people who show disease progression during the trial period in the eye with early AMD. A co-primary outcome measure is the rate of retinal adaptation. As this is a trial of a CE-marked device for an off-label indication, a further main aim of this trial is to assess safety of the mask in the cohort of participants with AMD.

Trial registration

International Standard Randomised Controlled Trials Register: ISRCTN82148651

Age-related macular degeneration; Biomarker; Hypoxia; Light mask; Randomized controlled trial