Myopia Toric VA Study

  • Research type

    Research Study

  • Full title

    MiSight® Effect of Uncorrected Astigmatism on Visual Acuity Non-Dispensing Study

  • IRAS ID

    315088

  • Contact name

    Michel Guillon

  • Contact email

    MGuillon@otg.co.uk

  • Sponsor organisation

    CooperVision International Limited

  • ISRCTN Number

    ISRCTN28719734

  • Duration of Study in the UK

    1 years, 0 months, 1 days

  • Research summary

    Myopia (short-sight) prevalence is increasing at a rapid rate amongst children and adolescents due the change in lifestyle with increasing use of near devices (smartphones, tablets, etc). To counteract this, special optic contact lenses that control myopia progression have been developed. The aim is to limit the amount of myopia in adulthood, as the higher the myopia the greater is the risk of eye diseases, some sight threatening, later in life.
    A key characteristic associated with the efficacy of the various contact lens optical designs is that they produce good vision quality for the children and adolescents to wear them most of the day as their main modality of vision correction. An aspect of myopia progression that has been identified in recent times is that the progression is not the same for all parts of the eye resulting in different degrees of myopia called astigmatism, hence, the need to correct both myopia and astigmatism in these special optical design contact lenses called toric contact lenses.
    However, the effect of not correcting astigmatism on visual performance and visual satisfaction is contact lens type dependent: uncorrected astigmatism creates greater visual detriment for multifocal contact lens designs than with spherical single vision designs. As myopia control contact lens designs are multifocal designs it is important to quantify the effect of uncorrected astigmatism produced by such designs in the specific case of a child / adolescent population to determine which level of astigmatism need to be corrected before developing a new range of contact lenses.
    MiSight® 1-day, the first CooperVision commercialised myopia progression control contact lens, has demonstrated high efficacy with a 59% decrease in myopia progression over a three-year period. The rationale for the proposed non-dispensing study is, therefore, to compare the visual performance achieved with MiSight® 1-day contact lenses with and without additional astigmatic corrections on children/adolescents population with varying levels of astigmatism. The astigmatic correction for testing in the clinic will be provided with spectacles.

    Lay Summary of results:
    The primary efficacy objective was to measure, in a myopic low astigmatic child / adolescent population, overall visual performance of MiSight® 1-day contact lens with and without astigmatism correction.
    The secondary objective was to measure, in a myopic low astigmatic child / adolescent population, overall subjective vision satisfaction achieved with MiSight® 1-day contact lens with and without astigmatism correction.
    The study results demonstrated that:
    i. the correction of astigmatism did not achieve superior overall visual performance compared with no astigmatic correction, but achieved superiority for several specific test conditions associated with challenging visual environments.
    ii. The correction of astigmatism did not achieve statistically superior overall vision satisfaction compared with no astigmatic correction despite a clinically highly significant median difference of 10 points on the 100-point scale. However, at intermediate distance the correction of astigmatism achieved both a statistically and highly clinically significant superiotity compared with no correction for astigmatism

  • REC name

    London - Bloomsbury Research Ethics Committee

  • REC reference

    22/PR/0650

  • Date of REC Opinion

    12 Jul 2022

  • REC opinion

    Further Information Favourable Opinion