Red Light Therapy for Myopia (Short-Sightedness)

Of all the emerging applications of red light therapy, myopia control in children may be the most exciting — and the most robustly supported by clinical evidence. Repeated low-level red light therapy (RLRL) has produced results in randomised controlled trials that have surprised even the researchers conducting them, with some studies showing a reversal of axial elongation in myopic children’s eyes.

This is not marginal, preliminary evidence. Multiple large RCTs, published in top-tier ophthalmology journals, have demonstrated clinically significant effects. The field is moving fast, with regulatory pathways being explored in several countries. This page examines what has been found, how it works, and what it means for the millions of children at risk of progressive myopia.

The myopia crisis

Myopia (short-sightedness) is now the most common refractive error worldwide. In East Asia, prevalence among young adults has reached 80 to 90 per cent in some populations. In Europe and the UK, prevalence has approximately doubled over the past 50 years and continues to rise.

The concern is not merely about needing spectacles. High myopia (greater than -6.00 dioptres) significantly increases the lifetime risk of:

• Retinal detachment — 5 to 10 times higher risk
• Myopic maculopathy — A leading cause of irreversible blindness in Asia
• Glaucoma — 2 to 3 times higher risk
• Cataracts — Earlier onset

The World Health Organisation has identified myopia as a major public health concern. Every dioptre of myopia prevented reduces lifetime risk of sight-threatening complications.

Why myopia progresses

Myopia occurs when the eyeball grows too long from front to back (axial elongation), causing distant light to focus in front of the retina rather than on it. In children, the eye is still growing, and myopia typically progresses throughout childhood and adolescence before stabilising in the early twenties.

The rate of axial elongation determines how myopic a child will become. Slowing this elongation is the primary goal of myopia control interventions, which currently include:

• Atropine eye drops (low-dose, 0.01 to 0.05%) — Modestly effective but with rebound effects on cessation
• Orthokeratology (overnight contact lenses) — Effective but requires lens wear and has infection risk
• Multifocal contact lenses — Moderate effectiveness
• Outdoor time — Strong epidemiological evidence that more outdoor light exposure reduces myopia risk

Red light therapy has entered this field as a potentially game-changing addition.

Repeated low-level red light therapy (RLRL)

RLRL for myopia uses a fundamentally different approach from the red light therapy discussed elsewhere on this site. The treatment involves a child looking into a specialised desktop device that delivers a low-power beam of red light (approximately 650nm) directly into the eye through the pupil.

This is deliberately delivered to the retina — the opposite of most red light therapy applications where eye exposure is avoided. The safety and rationale are specific to this application and supported by clinical trial data.

How it works

The precise mechanism is not yet fully established, but several hypotheses are supported by evidence:

Choroidal thickening. The choroid is the vascular layer behind the retina. In myopic eyes, the choroid is abnormally thin. RLRL consistently produces measurable choroidal thickening within hours to weeks of treatment. Zhou et al. (2022) demonstrated rapid choroidal thickening following RLRL sessions in myopic children (Ophthalmology, 129(12), 1342-1351).

A thicker choroid may physically resist scleral expansion and slow axial elongation. It may also improve metabolic support to the outer retina, which some researchers believe is involved in the signalling cascade that regulates eye growth.

Dopamine release. Retinal dopamine is a key neurotransmitter involved in the regulation of eye growth. Higher dopamine levels are associated with slower axial elongation — this is believed to be one mechanism through which outdoor light exposure protects against myopia. Red light at 650nm may stimulate dopamine release from retinal amacrine cells, mimicking part of the protective effect of outdoor light.

Mitochondrial function. Retinal photoreceptors and retinal pigment epithelium (RPE) cells are among the most metabolically active cells in the body. Red light at 650 to 670nm is absorbed by cytochrome c oxidase in these cells, enhancing mitochondrial function. Improved RPE metabolic function could strengthen the growth-regulatory signals that the retina sends to the sclera.

Key clinical trials

Jiang et al. (2022) — The landmark trial

Jiang et al. published what is arguably the most important study in this field: a multicentre, randomised controlled trial involving 264 Chinese children aged 8 to 13 with myopia of -1.00 to -5.00 dioptres.

Children were randomised to either RLRL (650nm, 2mW output, 3 minutes per session, twice daily, at least 4 hours apart) or a sham control group for 12 months.

Results (Ophthalmology, 129(5), 509-519):

• Axial elongation: The RLRL group showed a mean axial elongation of 0.13mm over 12 months, compared with 0.38mm in the control group — a 69 per cent reduction
• Refraction change: The RLRL group showed a mean myopic shift of -0.20D versus -0.79D in controls — a 75 per cent reduction in myopia progression
• Axial shortening: Remarkably, 21.6 per cent of children in the RLRL group showed actual shortening of axial length — meaning their eyes got shorter, a reversal of myopic change that no other intervention has consistently achieved
• Safety: No serious adverse events were reported. Comprehensive ophthalmic examinations including OCT, ERG, and fundus photography showed no signs of retinal damage

He et al. (2022)

He and colleagues conducted a 6-month RCT of RLRL in 115 myopic children. The treatment group showed:

• 77 per cent reduction in axial elongation compared with controls
• Significant choroidal thickening in the treated group
• No adverse events

Dong et al. (2023)

Dong et al. published 2-year follow-up data confirming that the effects of RLRL are sustained with continued treatment and that no cumulative retinal toxicity was observed over the extended treatment period (British Journal of Ophthalmology, 107(10), 1499-1505).

Comparison with other myopia control methods

The effect sizes from RLRL trials are striking when compared with established interventions:

Intervention	Reduction in axial elongation
RLRL (650nm)	60–77%
High-dose atropine (1%)	50–60% (but with rebound)
Low-dose atropine (0.01%)	12–20%
Orthokeratology	30–50%
Multifocal contacts	25–50%
Outdoor time (2+ hrs/day)	30–50% (prevention, not treatment)

RLRL appears to be the most effective single intervention studied to date, and it is the only one that has demonstrated consistent axial length shortening (as opposed to merely slowing elongation).

The devices

RLRL devices for myopia are purpose-built medical instruments, not consumer red light therapy panels. The Eyerising device (used in the Jiang et al. trial) delivers:

• Wavelength: 650nm
• Output power: ~2mW
• Beam diameter: Approximately 4mm at the pupil
• Treatment distance: The child looks into the device from a fixed distance
• Session duration: 3 minutes per session
• Protocol: Twice daily, separated by at least 4 hours, 5 to 7 days per week

These devices are not interchangeable with consumer red light therapy products. The power, wavelength, beam characteristics, and delivery method are precisely controlled. Looking into a consumer red light therapy panel is not equivalent and could potentially be harmful due to the much higher irradiance levels involved.

RLRL devices are currently available in China and are undergoing regulatory review in other markets. The Eyerising device received CE marking in Europe in 2023 and is seeking FDA clearance in the United States.

Safety considerations

The safety profile of RLRL has been extensively evaluated:

Short-term safety: Across multiple trials involving thousands of children, no serious adverse events have been reported. Transient afterimages (lasting seconds to minutes) are common but benign.

Retinal safety: Comprehensive retinal assessments including optical coherence tomography (OCT), electroretinography (ERG), multifocal ERG, and fundus photography have shown no evidence of retinal damage in treated children across studies lasting up to 2 years.

Theoretical concerns: Some ophthalmologists have raised concerns about the potential for long-term cumulative photochemical damage to photoreceptors, particularly given that the treatment targets children who will use the device for several years during their developmental period. The current data (up to 2 years) is reassuring, but longer follow-up is needed to fully exclude this risk.

What happens when treatment stops: Limited data suggests that some rebound effect occurs — axial elongation accelerates after treatment cessation, similar to the rebound seen with atropine discontinuation. This implies that ongoing treatment may be necessary throughout the myopia progression period (typically until late adolescence).

What about presbyopia?

Presbyopia — the age-related loss of near focusing ability — is a different condition from myopia, caused by stiffening of the crystalline lens rather than excessive axial length. The mechanisms through which RLRL slows myopia (choroidal thickening, dopamine release, scleral remodelling) are not relevant to presbyopia.

Shinhmar et al. (2020) conducted a small pilot study showing that 670nm red light exposure improved contrast sensitivity in older adults (Journals of Gerontology, 75(4), 658-664), potentially through improved mitochondrial function in ageing retinal cells. However, this did not address presbyopia (lens flexibility) and the clinical significance of the contrast sensitivity improvement is uncertain.

Red light therapy is not a treatment for presbyopia based on current evidence.

The bottom line

Repeated low-level red light therapy for myopia control is one of the most significant developments in paediatric ophthalmology in recent years. The evidence from multiple large RCTs is compelling: 60 to 77 per cent reduction in axial elongation, with some children showing actual reversal of myopic changes. The safety data to date is reassuring, though longer-term follow-up is needed.

This is not a home therapy you can improvise with consumer devices. RLRL requires a purpose-built ophthalmic device that delivers precisely controlled red light at 650nm directly to the retina. These devices are currently available in some markets and undergoing regulatory approval in others.

If you have a child with progressive myopia, discuss RLRL with a paediatric ophthalmologist or myopia management specialist. The evidence supports its consideration alongside established interventions. As longer-term safety data accumulates and regulatory approvals progress, RLRL may become a standard component of myopia management worldwide.