Slowing Axial Elongation in Pediatric Myopia Using C.A.R.E. Technology

This prospective interventional clinical study was designed to evaluate the effectiveness of Cylindrical Annular Refractive Element (C.A.R.E.) spectacle lenses in slowing axial elongation in children with myopia over a one-year period. The study follows the principles of the Declaration of Helsinki and received approval from the Al-Azhar University Institutional Ethics Committee (Approval No. Ophth._12/2023). Written informed consent was obtained from the parents or legal guardians of all participants prior to enrollment.

Participants

A total of 100 children aged 6-12 years with spherical equivalent refractive error between -0.75 and -6.00 diopters and astigmatism ≤1.50 diopters were recruited. Eligible participants were required to have best-corrected visual acuity of 0.1 logMAR or better and no history of ocular pathology or previous ocular surgery.

Children with amblyopia, strabismus, keratoconus, previous myopia control treatment (such as atropine therapy or orthokeratology), or poor compliance with spectacle wear were excluded.

Intervention

All participants were prescribed spectacle lenses incorporating Cylindrical Annular Refractive Element (C.A.R.E.) technology. These lenses contain a central optical zone for distance correction surrounded by concentric annular cylindrical elements designed to modify peripheral retinal defocus. Participants were instructed to wear the spectacles full-time during waking hours throughout the study period.

Study Procedures

Participants undergo comprehensive ophthalmologic examinations at baseline, 6 months, and 12 months. Assessments include:

Uncorrected visual acuity (UCVA)

Best-corrected visual acuity (BCVA)

Cycloplegic refraction

Axial length measurement using non-contact optical biometry

Outcome Measures

The primary outcome measure is the change in axial length over the 12-month follow-up period. Secondary outcomes include changes in spherical equivalent refractive error, visual acuity, and safety outcomes associated with spectacle lens wear.

Statistical Analysis

Statistical analysis will be performed using SPSS software. Continuous variables will be expressed as mean ± standard deviation. Data distribution will be evaluated using the Shapiro-Wilk test. Changes in axial length and refractive error over time will be analyzed using repeated-measures analysis of variance (ANOVA) or paired statistical tests when appropriate. A p-value less than 0.05 will be considered statistically significant.

Inclusion criteria

• Children aged 6-12 years at enrollment.
• Spherical equivalent refractive error between -0.75 and -6.00 diopters.
• Astigmatism ≤1.50 diopters.
• Best-corrected visual acuity of 0.1 logMAR or better.
• Ability to comply with full-time spectacle wear.
• Informed consent obtained from parent or legal guardian.

Exclusion criteria

• Amblyopia or strabismus.
• Keratoconus or other corneal pathology.
• Previous myopia control treatment (e.g., atropine therapy, orthokeratology).
• History of ocular surgery.
• Systemic disease affecting vision.
• Poor compliance with spectacle wear.