What the Fundus

Readers of this site will know I’m a sucker for a new myopia control article. Xu Cheng, MD, PhD, et al published Randomized trial of soft contact lenses with novel ring focus for controlling myopia progression in Ophthalmology Science in October 2022.

One of the biggest issues with myopia control is balancing the quality of vision with creating enough peripheral myopic blur to actually slow axial length growth. This group tested two new designs to see if they had similar efficacy to classic dual-focus designs.

To evaluate efficacy and vision with two prototype myopia control soft contact lenses with non-coaxial ring-focus designs (EE, for enhancing efficacy and EV, enhancing vision) compared to dual-focus (DF) and single-vision (SV) designs

Both EE and EV designs used more plus power (+7 D) than standard DF lenses.

the “plus” power in the prototype lenses is created without generating a coaxial point focus. Rays passing through concentric annular zones of the prototype lenses form a ring focus in front of the retina.

EE was designed to increase myopia control efficacy via introduction of a greater amount of plus power than conventional multifocal or dual-focus lens designs, while maintaining comparable visual performance. EV was designed to optimize vision while maintaining similar myopia control efficacy to a standard dual-focus lens.

The main difference between the EE and EV lens was that the EE lens’s treatment zones were positioned closer to the center. This is consistent with why you want to choose a CRT fit with as small an optic zone as is tolerable by the patient.

This study recruited 199 children between 7 and 12 years old and measure the effects of myopia control for a period of six months. The patients wore the lenses on average of 12-13 hours per day by the end of the study period.

After 26 weeks, EE, EV, and DF all had statistically significantly less axial elongation compared to SV

This is expected. Vision was pretty equal across lenses. However, haloes were reported with the EE and DF lenses than with the EV and SV lenses.

If these prototype lenses are released, I could see starting with the EE lenses. However, if the patient complains about night vision issues or otherwise vision quality issues, they could be shifted to the EV version and still get decent myopia control efficacy.