Plain English Summary
Background and study aims
Photoreceptors are cells found at the back of the eye which convert light to an electric signal. They demand more energy than any other tissue in the body. Unfortunately, as people grow older, the energy-producing units in the cells (mitochondria) become less efficient and produce less energy. This is associated with inflammation which contributes to age-related macular degeneration (AMD) and aging in general. AMD is the most common cause of blindness in the elderly and unfortunately there is no prevention or cure for this. A molecule in the mitochondria can absorb a particular wavelength of light (670nm – which is red) and increase energy production. Studies have also shown that inflammation associated with aging and AMD is reduced by exposure to this red light. The aim of this study is to test whether exposure to 670 nm wavelength light can improve visual function in aging and AMD.
Who can participate?
Patients with dry AMD and healthy older people
What does the study involve?
Participants hold a device emitting red light to their eyes for two minutes every day for one year and their visual function is measured before, during and 1, 3, 6 and 12 months after this treatment.
What are the possible benefits and risks of participating?
This study will show whether exposure to 670 nm light can improve visual function in aging and AMD. There are no known risks.
Where is the study run from?
Moorfields Eye Hospital (UK)
When is the study starting and how long is it expected to run for?
January 2017 to February 2019
Who is funding the study?
1. Moorfields Eye Charity (UK)
2. Fight for Sight (UK)
Who is the main contact?
Dr Chrishne Sivapathasuntharam
A pilot study to investigate the effect of 670 nm light on visual function in ageing and age-related macular degeneration
Photoreceptors demand more energy than other tissue in the body. Unfortunately, as people grow older, mitochondria become less efficient and produce less energy. This is associated with inflammation which contributes to age-related macular degeneration (AMD) and aging in general. AMD is the commonest cause of blindness in the elderly and unfortunately, there is no prevention or cure for this.
A molecule in mitochondria can absorb a particular wavelength of light (670nm – which is red) and increase energy production. This has been shown in different cells, including the retina. Studies have also shown that inflammation associated with aging and AMD is reduced by exposure to this red light.
This is a pilot study to see if exposure to 670 nm wavelength of light can improve visual function in aging and AMD.
London - Stanmore Research Ethics Committee, 24/01/2017, ref: 16/LO/2022
Pilot non-randomised study
Primary study design
Secondary study design
Non randomised study
Patient information sheet
Not available in web format, please use contact details to request a participant information sheet
Dry age-related macular degeneration
Participants will hold a device emitting 670 nm light to their eyes for two minutes every day for one year and have their retinal function measured before, during and 1, 3, 6 and 12 months after.
Primary outcome measure
Visual function determined by photoreceptor function over time, measured at 1, 3, 6 and 12 months
Secondary outcome measures
Measured at 1, 3, 6 and 12 months:
1. Metrics of photoreceptor function, assessed psychophysically and electrophysiologically
2. Visual acuity and low-luminance acuity
3. Light-adapted 30 Hz flicker peak time, measured using a RETeval device
4. Anatomical changes, evaluated using SD OCT, autofluorescence and colour photographs
5. Safety and compliance of 670 nm light exposure
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Patients with dry AMD and healthy aged subjects
2. Aged 50 years and above
Target number of participants
Participant exclusion criteria
1. Co-existent ocular disease: any ocular condition is present such that, in the opinion of the investigator, might affect the inflammatory status, visual acuity or cone function during the course of the study
2. A substantial cataract that, in the opinion of the investigator, is likely to be decreasing visual acuity by 3 lines or more (e.g. cataract would be reducing acuity to 6/12 or worse if eye was otherwise normal) and early cataract that might be susceptible to growth under the influence of 670 nm light
3. History of major ocular surgery (including cataract extraction, scleral buckle, any intraocular surgery, etc.) within prior 3 months or anticipated within the next 6 months following enrolment
5. Allergies to adhesives or any other component used
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Moorfields Eye Hospital
162 City Road
Moorfields Eye Charity
Funding Body Type
Funding Body Subtype
Fight for Sight
Funding Body Type
private sector organisation
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Planned publication in a high-impact peer reviewed journal in 2018/2019.
IPD sharing statement
The datasets generated during and/or analysed during the current study is not expected to be made available and will be held with the sponsor.
Intention to publish date
Participant level data
Not expected to be available
Basic results (scientific)