Safety, efficacy, and response variability of multifocal and dual-focus soft contact lenses in myopia control: A...

Myopia is a major global public health concern, projected to affect half the world's population by 2050. High myopia is strongly linked to vision-threatening complications. Multifocal (MF) and dual-focus (DF) soft contact lenses are among the most widely studied interventions for slowing myopia progression. This review summarizes proposed mechanisms, efficacy, variability, and safety considerations of MF soft contact lens (MFSCL) use in children. A narrative synthesis was conducted using findings from randomized controlled trials, paired-eye studies, and recent animal and human investigations. Emphasis was placed on evolving mechanistic theories, cross-population efficacy differences, and clinical implications of study heterogeneity. Initially attributed to reducing peripheral hyperopic defocus, MFSCL efficacy is now thought to involve complex retinal signaling, including competing defocus cues and extended depth-of-focus effects. Pivotal trials such as MiSight 1 day and BLINK reported 43%-59% reductions in axial elongation compared with single-vision controls. However, effects vary by population, with Asian cohorts often showing smaller efficacy, and by individual factors such as lens design, add power, centration, pupil size, genetic predisposition, and baseline progression rate. Methodological differences - study design, compliance, dropout rates, and outcome definitions - further complicate comparisons. Importantly, MFSCLs demonstrate an excellent safety record in children, with adverse event rates comparable to adults and lower than those reported with overnight orthokeratology. MFSCLs are a safe and effective option for pediatric myopia management, though variability highlights the need for personalized treatment and close monitoring. Future work should clarify mechanisms, standardize reporting, and explore combination therapies to optimize outcomes for partial responders.