Association Between Pupil Area and the Efficacy of Peripheral Defocus Spectacle Lenses in Myopia Control.

Purpose: To investigate whether pupil area influences the effectiveness of peripheral defocus spectacle lenses in controlling axial elongation and refractive error progression among myopic children. Methods: This retrospective analysis included 310 myopic children ages 7 to 14 years. Each participant wore one of three myopia control lens types for at least 12 months: type A, defocus incorporated multiple segments (DIMS) lenses; type B, highly aspherical lenslets; or type C, personalized freeform optical design. Participants were grouped by pupil area (above or below the mean). Axial length and spherical equivalent refractive error were measured at baseline, 6 months, and 12 months. A linear mixed-effects model was used to evaluate the effect of the interaction between pupil area and lens type on axial elongation. Results: Among children with larger pupils, lens type B was associated with less axial elongation and refractive error progression at 12 months compared with types A and C (P < 0.001). In contrast, no significant differences among lens types were observed in children with smaller pupils. An interaction term (β = -0.086, P = 0.002) indicated that the efficacy of lens type B may be influenced by pupil area. Conclusions: Pupil area may influence the efficacy of peripheral defocus spectacle lenses for myopia control. Children with larger pupils demonstrated greater benefit from highly aspherical lenslets, suggesting that pupil area should be considered in clinical decision-making. Translational Relevance: Pupil area may influence the clinical performance of peripheral defocus lenses, supporting personalized myopia management in children.