Concern over long-term RLRL use disputed

A recent Chinese study investigating the potential retinal effects of repeated low-level red light (RLRL) therapy for myopia control found long-term use may be associated with structural changes in cone photoreceptor density. Eyerising International, the company behind the RLRL Myopia Management Device, is challenging these findings, raising concerns about the study’s methodology and clinical design.

Using adaptive optics scanning laser ophthalmoscopy (AOSLO), the authors reported a reduction in cone density within 0.5mm of the foveal centre in the RLRL-treated group compared to controls, particularly pronounced in the temporal region with abnormal drusen-like lesions detected in some of these cases.

Published in JAMA, authors led by Dr Xinyi Liao, Peking University People’s Hospital, argued their findings support the need for further research to evaluate longer-term safety of RLRL therapy in similar individuals.

In response, Eyerising published a comment highlighting several “critical methodological and clinical issues” to consider before drawing definitive conclusions, and challenged the study’s retrospective design, small sample size and inclusion of both eyes.

“Notably, according to our knowledge, one independent randomised controlled trial and one cross-sectional study conducted in children in China have yielded findings that are completely opposite to those reported by Liao et al,” wrote Dr Mingguang He, professor of ophthalmology at the University of Melbourne and the Sun Yat-sen University in China and the chief medical officer at Eyerising International.

Both studies cited by Prof He used cone density measured by AOSLO imaging as a key safety outcome and confirmed that higher levels of myopia are associated with lower cone density. The randomised controlled trial was conducted in Beijing Tongren Hospital in China (Jie et al) involving 336 children. Their findings found no difference in cone density between the RLRL and control groups after a 33-month follow-up. This study is currently under submission.