Effects of monochromatic light on eye growth regulation and Myopia control

The application of monochromatic light in myopia has remained a research hotspot in the field of myopia prevention and control. With rapid advances in clinical applications, numerous studies have confirmed its unique potential in slowing axial elongation in children and adolescents. However, the underlying mechanisms of monochromatic light remain inconclusive within the academic community. This review summarizes recent progress in animal studies investigating the effects of monochromatic light characteristics-including wavelength, exposure duration, light intensity, and exposure initiation period-as well as related circadian rhythm disturbances on ocular growth and refractive development. Current evidence suggests that monochromatic light may regulate eye growth through mechanisms such as modulation of retinal cone signaling, dopamine metabolism, and choroidal thickness alterations. In clinical research, investigations of monochromatic light have primarily focused on repeated low-level red light (RLRL) therapy. As an emerging intervention, RLRL has demonstrated potential in slowing myopia progression. However, its long-term efficacy and safety remain topics of ongoing debate. This review synthesizes current findings from both animal and human studies, explores the underlying biological mechanisms, and discusses the challenges associated with the clinical application of RLRL therapy.