Visual acuity, vision performance acceptability and subjective over-refraction in myopic children wearing dual-focus contact lenses
Nicola Logan, Paul Chamberlain, Chris Hunt, Graeme Young & the MiSight® 1 day study group
Purpose: To compare visual acuity (VA), vision performance acceptability and over-refraction with the dual focus MiSight® 1 day (MS) contact lens and the single vision Proclear® 1 day (SV) contact lens in children with myopia.
Method: A randomised control trial of 144 children aged 8 to 12 years was conducted. Children were randomised to wear either MiSight® 1 day or Proclear 1 day (both omafilcon A, CooperVision, Inc.) over a 3-year period. Assessments included monocular and binocular high-contrast logMAR VA at distance and near, vision performance acceptability of the contact lenses using questionnaires and back vertex power of lenses dispensed versus refractive error measured as both manifest and by cycloplegic autorefraction.
Results: No statistically significant differences were seen in high contrast VA at distance (MS -0.03 ±0.06 logMAR, SV -0.01 ±0.05 logMAR) or near (MS -0.06 ±0.10 logMAR, SV -0.05 ±0.09 logMAR) with either lens design (P<0.01). No significant differences in acceptability of vision with the contact lens was found between groups. The difference in spherical back vertex power of lens dispensed compared spherical equivalent refractive error as measured with both cycloplegic autorefraction and manifest refractive error was similar for both the MS (lens dispensed was 0.11 ±0.24D more myopic than cycloplegic SER and 0.09 ±0.24D more hyperopic than manifest SER) and SV contact lenses (cycloplegic difference -0.09 ±0.26D, manifest difference +0.14 ±0.24D) (Mixed model ANOVA P≥0.12).
Conclusions: The findings demonstrate that MS contact lenses for myopia management provided good levels of VA and comparable with SV contact lens correction in children. In this cohort manifest refraction is sufficient to dispense MS contact lenses without using cycloplegia. The standard fitting methods and ease of use makes this lens suitable for young children with myopia.
1st Author Biography: Nicola is Director of Research for the Optometry and Vision Science Research Group, School of Optometry, Aston University, Birmingham, UK. Nicola is a qualified and registered optometrist and a Reader in Optometry at Aston University. Nicola’s research interests are the epidemiology of refractive error, the development and aetiology of myopia and myopia control. Nicola runs a myopia clinic at Aston University and she collaborates with other researchers working in the field of myopia as part of The International Myopia Institute. Nicola was awarded the Neil Charman Medal for Excellence in Research from The College of Optometrists, UK.
*Data correct at the time of submission to BCLA by NCC.