The wearing performance of MiSight 1 day versus Proclear 1 day over a 3 year period

Paper title:  Visual acuity, vision performance acceptability and subjective over-refraction in myopic children wearing dual-focus contact lenses

Authors: Nicola Logan (1), Paul Chamberlain (2), Chris Hunt (3), Graeme Young (3)

1. Aston University, Birmingham, UK
2. CooperVision Inc, Pleasanton, California, USA
3. Visioncare Research Ltd., Farnham, Surrey

Date: Feb 2021

Reference:  Logan N, Chamberlain P, Hunt C, Young G et al.  Visual acuity, performance acceptability and subjective over-refraction in myopic children wearing dual-focus contact lenses.  Contact Lens Anterior Eye 2021;44-S1-21 [Link to abstract]

This randomised control trial compared the overall visual performance of two daily disposable contact lens designs by Coopervision for 144 myopic children aged between 8 and 12 years.

The children wore either the Proclear 1 day (single vision design) or MiSight 1 day (designed or myopia management with dual focus optics) for the 3-year study period with lens powers being the spherical equivalent refractive (SER) error found following manifest and cycloplegic auto-refraction.

The lenses were then compared for their acceptability of wear and for their ability to provide accurate refractive correction according to the original refractive error.

The children's high contrast logMAR acuities for distance and near were assessed monocularly and binocularly and questionnaires were used to evaluate their perception of visual performance during wear.

The results found there was no statistically significant differences between the lens types for either:

• the acceptability of the vision with wear, as reported by questionnaire, or
• the distance and near logMAR visual acuities
  • for distance, MiSight and Proclear lenses showed differences of -0.03 logMAR and -0.01 logMAR, respectively
  • for near, these values were -0.06 logMAR and -0.05 logMAR, respectively
• the final dispensed lens power compared to the refraction values
  • MiSight showed an over-refraction cycloplegic difference of -0.11D and a manifest difference of +0.09D
  • Proclear was seen to require -0.09D more over-refraction than the cycloplegic SER and +0.14D more compared to the manifest SER

The MiSight design showed no significant difference for the final chosen lens power compared to manifest refraction or cycloplegic auto-refraction results and the visual performance when worn is comparable to the single vision Proclear design.

Eyecare practitioners can confidently dispense lens powers for MiSight based on non-cycloplegic refraction.

Eyecare practitioners can be confident when dispensing MiSight that initial spherical equivalent lens power choice should require little over-refractive adjustment even when the refraction was not found by cycloplegic auto-refraction.

During wear, children are likely to experience good visual acuity on par with a single vision contact lens.

More information on the range of lens powers assessed during the study would tell us if there was a difference in acuities for differing lens powers or if the quality of visual performance held true across the MiSight power range.

The children's logMAR acuities were also assessed under high contrast conditions.  It would be useful to know if there was a performance difference under lower contrast conditions compared to the single vision version to reflect lighting changes for a wearer during a wear period.

Title: Visual acuity, vision performance acceptability and subjective over-refraction in myopic children wearing dual-focus contact lenses

Authors: Nicola Logan, Paul Chamberlain, Chris Hunt, Graeme Young

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.

Methods: 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 log-MAR) 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.

[Link to abstract]