Spectacles with non‑refractive opaque features for paediatric myopia: a safety pilot trial

Optical myopia-control strategies predominantly introduce competing defocus, extend depth of focus, or modify retinal contrast [ 1 ]. A single-vision spectacle lens utilising non-refractive, light-absorbing opaque features to alter spatiotemporal retinal luminance during natural eye movement without defocus, blur, or scatter was developed [ 2 ]. Visual performance in adults was superior to a competing defocus design [ 3 ]. In-vivo myopia efficacy is unknown, and experimental evidence that partial occlusion could potentiate myopiagenesis [ 4 ], underpinning the need for paediatric safety data. A contact-lens counterpart demonstrated safety in a small pilot [ 5 ]; however, spectacle delivery is preferable for younger children. This 14-month, three-phase, within-participant crossover pilot assesses safety (primary) and axial elongation (secondary) in myopic children.