Repeated low-level red-light therapy for childhood myopia: Efficacy, mechanisms, rebound effects, safety boundaries, and clinical standardization.
Level 5 - mechanism / opinion, no new human data
Narrative review without formal systematic review or meta-analytic methodology
PubMed 42349599 · doi:10.1016/j.pdpdt.2026.105554
What was done
The authors conducted a structured narrative review evaluating repeated low-level red-light therapy (RLRL) for childhood myopia control. They searched PubMed/MEDLINE, Embase, Web of Science, the Cochrane Library, and Scopus from database inception through May 2026. The review prioritized randomized clinical trials, post-treatment follow-up studies, choroidal and retinal imaging evaluations, and laboratory radiometric safety assessments across premyopia, established myopia, and high myopia.
What was found
The abstract reports no quantitative pooled metrics or numerical values. Short-term randomized controlled trials consistently demonstrated reduced axial elongation—with some observing apparent axial shortening—relative to spectacle or sham controls. Human mechanistic studies demonstrated rapid choroidal thickening and increased choroidal perfusion following treatment. However, follow-up studies identified rebound axial elongation following treatment discontinuation. Safety assessments identified reports of retinal injury, transient optical coherence tomography lesions, cone-density changes, and substantial device-to-device radiometric variability.
Why it matters
RLRL has seen rapid clinical adoption for pediatric myopia, but this review highlights that therapeutic benefit cannot be generalized across all red-light devices. It provides a framework for clinicians emphasizing that treatment requires strict device dosimetry, pre-treatment and follow-up retinal imaging, and clear protocols for discontinuation to manage rebound effects.
Limits
The review is narrative rather than a formal systematic review or meta-analysis because primary studies frequently failed to report reproducible device parameters. The underlying evidence base is geographically concentrated, lacks long-term ocular safety surveillance, and relies on biological mechanisms that remain incompletely verified in humans beyond choroidal changes.
Cited by
- context The lack of long-wavelength light exposure is a contributing driver in the development of myopia.
- supports Repeated low-level red laser therapy used to treat myopia in children has caused retinal burning and localized damage due to caustic optical hot spots.