What the Fundus

Red light therapy seems to be the new thing in regards to fixing everything from pre-mature aging of the skin, meibomian gland disease, and, it turns out, amblyopia.

We intend to use a device that emits red light at 650 nm in wavelength based on the fact that it has already been approved and widely used for amblyopia treatment in China so that the safety of the participants can be potentially maximized

The “we” in the previous quote are the authors of Effect of Repeated Low-Level Red-Light Therapy in Myopia Control in Children: A Multicenter Randomized Controlled Trial published in the journal Ophthalmology. They exposed 117 children to repeated low-level red-light (RLRL) therapy and monitored 129 children with simple glasses correction.

The RLRL treatment was provided by a desktop light therapy device which emits red light of 650 nm in wavelength, at an illuminance level of approximately 1600 lux and a power of 0.29 mW for a 4-mm pupil (Class I Classification), and was administered at home under supervision of parents, 3 minutes per session, twice per day with a minimum interval of 4-hours, five days per week.

It is well known that increased outdoor time with bright light exposure is excellent for reducing progression of myopia. The purpose of this study was to see if using intense, short exposures to this type of light would perhaps offer the same effect. This was based on the following.

The selection of treatment modality is also based on unpublished anecdotal findings from children who used the device for the purpose of amblyopia treatment, where increased choroidal thickness and blood flow and stabilization of axial elongation were observed.

The findings were startling to me.

In this 12-month, multicenter randomized clinical trial, RLRL treatment slowed axial elongation by 0.26 mm and SER progression by 0.59 D compared with SVS, respectively, representing a 69.4% and 76.6% slowing axial elongation and myopic refraction progression

That puts it well within the range of what ortho-k can do in a significantly easier modality. Imagine a parent with the choice of either dealing with a small child adapting to a hard contact lens that you sleep in or six minutes light therapy per day. Obviously more work needs to be done, and I’m not ready to institute this into my myopia control armamentarium any time soon, but this would be really cool.