While red-light therapy has recently gained attention as a potential strategy for slowing myopia progression in children, a new laboratory study published in JAMA Ophthalmology suggests that some commercially available devices may reach retinal safety limits far sooner than their recommended treatment durations.
The findings raise concerns about whether certain laser-based systems could expose the retina to levels of light that exceed established safety standards, particularly when used repeatedly in pediatric patients.
Let’s start with the basics: What is red light therapy for myopia?
Repeated low-level red-light therapy (RLRL) is a treatment approach designed to slow myopia progression by exposing the eye to controlled bursts of red light.
A couple of notes:
- The therapy is typically delivered through a desktop device that emits light in the red wavelength range, usually around 650 nm.
- The treatment protocol commonly involves short sessions—often about 3 minutes—performed twice daily, several days per week.
And the research on it so far?
Researchers believe the therapy may influence eye growth by affecting retinal signaling pathways or altering choroidal thickness, which can help regulate axial elongation, the primary driver of worsening myopia.
In fact: Clinical trials conducted primarily in Asia have reported reductions in myopia progression and axial elongation in children receiving the therapy, contributing to its rapid adoption in some regions.
Why has this treatment gained attention in recent years?
Myopia rates are rising globally, particularly among children. As prevalence increases, researchers have been exploring new approaches to slow eye growth and prevent high myopia later in life.
The appeal: Red-light therapy has attracted interest because it is noninvasive and can be administered at home—and early clinical studies have reported promising results such as slowed axial elongation (AE) and reduced refractive progression in pediatric patients.
But at the same time, safety questions remain—particularly because the therapy delivers light directly to the retina during repeated exposures.
So where does this new research come in?
To evaluate potential safety risks, investigators conducted a laboratory-based study assessing the optical output of several commercially available red-light therapy devices used for myopia control.
The goal was to determine whether these devices meet established safety standards defined by the American National Standards Institute (ANSI) for ophthalmic instruments.
Researchers specifically evaluated:
- How much light energy each device emits
- How quickly exposure reaches recommended safety limits
- How the devices are classified under ANSI laser safety guidelines
Which devices were evaluated in the study?
The researchers tested four commercially available red-light therapy devices:
- Eyerising Myopia Management Device (EyeRising International)
- Sky-n1201 (Beijing Ming Ren Shi Kang Science & Technology Co., Ltd)
- Future Vision (Hunan Medical Technology Co, Ltd)
- AirDoc Photobiomodulation (Beijing Airdoc Technology Co, Ltd)
Laboratory measurements assessed the optical power emitted by each device and calculated the amount of light reaching the retina under different pupil sizes and exposure conditions.
How did researchers evaluate device safety?
Safety classification was determined according to established ANSI ophthalmic standards. The team measured radiometric power using an integrating sphere radiometer and calculated retinal irradiance levels at different distances and pupil diameters.
The key metric was the time required for each device to reach the ANSI “Group 1” safety limit, which represents the maximum safe exposure threshold.
What did the researchers find?
Two of the laser-based devices reached safety limits much faster than expected.
For a 7-mm pupil:
- Sky-n1201 reached the safety limit in about 2.8 seconds
- EyeRising reached the limit in about 1.4 seconds
Both times were far shorter than the recommended treatment duration of approximately 180 seconds for typical therapy sessions.
By contrast:
- The Future Vision device remained within limits under extended exposure times
- The light-emitting diode (LED)-based AirDoc device produced diffuse illumination and stayed well within safety limits
What do these findings suggest about pediatric safety?
The results indicate that some laser-based red-light therapy systems may expose the retina to irradiance levels that exceed established safety thresholds when used according to current treatment protocols.
According to the researchers, this raises concerns about the potential risk of retinal injury, particularly when the therapy is administered repeatedly to children whose eyes are still developing.
Are there emerging clinical concerns?
Beyond laboratory measurements, some clinical reports have described retinal changes following repeated red-light therapy.
For example, previous research examining children undergoing long-term RLRL treatment found reductions in cone photoreceptor density in parts of the retina, suggesting possible cellular-level retinal changes associated with prolonged exposure.
- Although such findings remain under investigation, they have added urgency to calls for further safety evaluation.
Even further: Our coverage on 2024 research into this subject also led to questionable safety results, with the authors of that study calling for future research to include “high-resolution imaging and more advanced functional testing to assess retinal integrity.”
Interesting … any limitations to consider when interpreting the findings?
The study was conducted in a controlled laboratory environment rather than a clinical setting. As a result, it did not evaluate patient outcomes or directly measure retinal damage.
- Instead, the analysis focused on device output and theoretical exposure calculations based on established safety guidelines.
Further clinical studies will be needed to determine how these laboratory findings translate to real-world treatment use.
Why might this matter for clinicians and regulators?
Red-light therapy has been widely adopted in parts of Asia, and is being considered internationally as a potential treatment for pediatric myopia.
The authors emphasize that independent safety testing is essential before the therapy becomes more widely used—and that balancing potential therapeutic benefits with retinal safety will be critical when evaluating whether these devices should be used routinely in children.
Take home.
A laboratory evaluation of four red-light therapy devices found that some laser-based systems may reach retinal safety limits in seconds—far shorter than the recommended treatment duration.
The findings highlight the need for further independent safety validation to ensure that therapies intended to slow myopia progression do not inadvertently pose risks to pediatric retinal health.