Does discontinuing MiSight cause a rebound effect?

Paper title: Rebound Effect in the Misight Assessment Study Spain (Mass)

Authors: Alicia Ruiz-Pomeda,¹ Francisco Luis Prieto-Garrido,² Jose Luis Hernández Verdejo³ and César Villa-Collar⁴

1. Ophthalmology Department, Hospital Universitario de Móstoles, Móstoles, Spain
2. Department Optics I: Optometry and Vision, Universidad Complutense de Madrid, Madrid, Spain
3. Department Optometry and Vision, Universidad Complutense de Madrid, Madrid, Spain
4. Doctoral and Research School, European University of Madrid, Madrid, Spain

Date: Jan 2021

Reference: Ruiz-Pomeda A, Prieto-Garrido FL, Hernández Verdejo JL, Villa-Collar C. Rebound Effect in the Misight Assessment Study Spain (Mass). Curr Eye Res. 2021 Aug;46(8):1223-1226

[Link to abstract]

This study examined if cessation of MiSight contact lens wear for myopia control produces a rebound effect. The study involved three groups:

1. MiSight-C: 13 children undergoing 3 continuous years of MiSight wear
2. MiSight-D: 18 children undergoing 2 continuous years of MiSight wear followed by 1 year of single vision spectacles
3. Single Vision-C: 24 children wearing single vision glasses for 3 continuous years

There was no statistically significant difference in myopia progression or axial elongation between the three groups in the third year of the study. This means no rebound effect was observed. Clinically, this research indicates that children should be able to cease myopia control with MiSight contact lenses at around the age of 12-13 years with no rebound effect. 

However, the results raise questions regarding the long-term efficacy of MiSight for myopia control. Unexpectedly, the treatment group wearing MiSight (MiSight-C) displayed a non-statistically significant difference in axial length and myopia progression to the children who have ceased treatment (MiSight-D and Single-Vision C). This indicates the treatment effect of MiSight contact lenses may decrease with time.

It should be noted that the mean ages of the MiSight-C (12.9 ± 1.2) and MiSight-D (13.2 ± 1.2) groups were significantly older than the control group (11.9 ± 1.3), which may affect the reliability of the results. Further large-scale research is required to investigate this phenomenon further and the age at which myopia control treatment can be safely ceased. 

This indicates that a 1 year cessation of MiSight contact lenses in children aged 12-13 years of age does not produce a significant change in myopic progression. This indicates that, if desired, this may be an appropriate age to consider stopping MiSight contact lens wear without causing an increase in level of myopia progression.

As there were discrepancies in the mean ages of the groups at the commencement of the study, further long term randomised control trials are required to investigate this further.

Title: Rebound Effect in the Misight Assessment Study Spain (Mass)

Authors: Alicia Ruiz-Pomeda, Francisco Luis Prieto-Garrido, Jose Luis Hernández Verdejo, César Villa-Collar

Purpose: To investigate whether cessation of MiSight contact lens (CLs) wear for myopia control produces rebound effect.

Methods: This study recruited participants who had just completed the MASS Study, a two-year randomized clinical trial designed to assess the efficacy of MiSight® CLs versus distance single vision (SV) spectacles in myopic children. To assess the rebound effect, axial length progression was taken into account in those children that continued one more year of follow-up. At this visit, children were divided into three groups: MiSight-C group, in which children from the original study group continued MiSight CLs wear for the duration of the study; MiSight-D group, in which children from the original study group discontinued MiSight CLs wear in the last year; and SV-C group, in which children from the original control group continued wearing single-vision spectacles for the duration of the study. The last group was considered as the control group.

Results: Of the 74 children who completed the MASS study, 55 children completed the 1-year follow-up and were included in the analysis. Thirteen children were included in the MiSight-C group, 18 in the MiSight-D group, and 24 in the Single Vision-C group. Axial length and myopia progression in the last year were 0.15± 0.11 mm, 0.22± 0.11 mm, 0.21± 0.10 mm and −0.37±0.44D, −0.46±0.39D and −0.55±0.45D for the three groups, respectively. No significant differences in axial elongation and myopia progression were found among the three groups of participants

Conclusions: Over a one-year period, neither myopia progression nor eye growth was faster for the subjects who discontinued MiSight contact lens wear compared to those who continued to wear MiSight contact lenses or those who continued to wear single-vision spectacles, indicating no rebound effect with MiSight contact lenses for 2 years.

[Link to abstract]