Advanced Technology for Myopia Control in Children and Young Adults

Role of Advanced Technological Approaches for Myopia Control in Myopic Patients: A Randomized Controlled Trial of Lenslet Spectacles vs. Violet Excitation Filter Glasses vs. Single Vision Lenses

Myopia, or nearsightedness, is increasing rapidly worldwide, especially in children and young adults. This study tested two advanced treatments for slowing myopia progression with one control group: special lenslet spectacles (Stellest with highly aspherical lenslet technology) and violet excitation filter glasses (wavelength 420 nm) and Single vision lenses for controls. The study enrolled 90 participants aged 8 to 20 years from schools and universities in Faisalabad, Pakistan. Participants were randomly assigned to one of three groups: lenslet spectacles, violet filter glasses, or single vision lenses (control group). Visual acuity, contrast sensitivity, Spherical Equivalent and axial length were measured at the start and again after 3, 6, and 9 months and one follow up after cessation of treatment. The study aimed to determine whether these advanced technologies can effectively slow myopia progression compared to standard glasses, providing head-to-head evidence on emerging and established optical interventions for myopia control.

This is a randomized controlled trial (RCT) with three parallel groups. The study was conducted at schools and the Universities in Faisalabad, Pakistan. The total study duration was almost one year (July 2025 to May 2026), with each participant undergoing atleast 3 months of active treatment with 3 follow ups. The sample size was 30 participants per group (total N=90), after drop put of patients, calculated using G*Power (repeated measures ANOVA, 3 groups × 4 time points, medium effect size f=0.25, α=0.05, power=0.8). Simple random sampling was used, with participants allocated to groups using an online research randomizer. Inclusion criteria: axial myopia (high, moderate, or severe), age 8-20 years, both genders, willingness to wear glasses. Exclusion criteria:

other ametropia, contact lens users, prior myopia treatment, ocular or systemic disease, ocular surgery, non-cooperative patients. Lenslet group: Essilor Stellest spectacles with Highly Aspheric Lenslet Target technology, 1.6mm thickness, refractive index 1.56, UV 400nm protection, antireflective coating; worn all waking hours. Violet filter group: plastic lenses with 420nm violet excitation filter; worn 3 hours daily (11 AM to 2 PM) to align with circadian rhythm. Control group: single vision lenses (refractive index 1.56). Primary outcome measures: change in axial length (measured by ocular biometer) and change in cycloplegic refraction. Secondary outcome measures: visual acuity (LogMAR chart), contrast sensitivity (Vistech chart). Follow-up assessments at 3, 6, and 9 months. Statistical analysis: repeated measures Linear mixed model using SPSS version 26 to compare within-group and between-group changes.

Inclusion Criteria:

• Diagnosis of axial myopia (high, moderate, or severe)
• Age between 8 and 20 years (inclusive)
• Male or female
• Willingness to wear prescribed glasses as instructed
• Willingness to attend all follow-up visits (3, 6, and 9 months)
• Written informed consent from participant or parent/guardian for minors

Exclusion Criteria:

• Any ametropia other than axial myopia (e.g., hyperopia, astigmatism >1.50D)
• Current contact lens users
• Prior or concurrent myopia treatment other than study interventions
• Any ocular disease (e.g., cataract, glaucoma, retinal disorders)
• Any systemic disease affecting vision (e.g., diabetes, Marfan syndrome)
• History of any ocular surgery
• Allergic or physical intolerance to glasses materials
• Non-cooperative patients unwilling to comply with study procedures