Examination of Myopia Progression and Consequences and Mechanisms of Soft Bifocal Contact Lens Myopia Control
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Ohio State University
- Enrollment
- 248
- Locations
- 4
- Primary Endpoint
- The statistical correlation between choroidal thickness and axial length
Study Overview
Brief Summary
This project intends to provide important, previously unmet answers regarding biological associations with myopia (nearsightedness) progression in order to improve the ability to predict patients who are most likely to benefit from myopia control, as well as questions frequently posed by patients and practitioners about the side effects, mechanism, and discontinuation of soft bifocal contact lens myopia control. The first three aims examine the association between biological variables that can be measured non-invasively and myopia progression, and they will be conducted regardless of the outcome of the currently in progress BLINK Study. The last three specific aims will be conducted if soft bifocal contact lenses slowed myopia progression by 30% or more in the BLINK Study, and they can be investigated with very few additional measurements.
Detailed Description
The primary goal of the BLINK2 Study is to determine correlates of myopia progression using non-invasive measurement of biomarkers, such as choroidal thickness and intrinsically photosensitive retinal ganglion cell-mediated pupil function, and outdoor light exposure in children. If multifocal contact lenses slow the progression of myopia by 30 percent or more compared to single vision contact lenses during the BLINK Study, the investigators will also answer important questions about the consequences and mechanism of the treatment effect, such as whether multifocal contact lens wear alters accommodative function and whether or not the treatment benefit is transient. Specifically, the investigators will investigate whether myopia progression is slowed or simply delayed by multifocal contact lens wear and whether there is a rebound in myopia progression, an increase in progression rate, after discontinuation of multifocal contact lenses. The investigators will identify myopic children who will most benefit from myopia control by determining those who are most likely to progress, thereby maximizing the potential for benefit and minimizing risk. The investigators will accomplish this goal by investigating the effect on progression of the most important ocular and environmental risk factors recently hypothesized to control eye growth. The project will collect the most extensive longitudinal dataset ever on choroidal thickness in childhood myopia. The investigators will test the important question of whether time outdoors and light exposure influence myopia progression after onset in addition to whether these affects are mediated by intrinsically photosensitive retinal ganglion cells. If soft multifocal contact lenses show a clinically meaningful slowing of myopia progression, we will also answer important questions asked routinely by our clinical colleagues. The investigators will know the accommodative effect of multiple years of multifocal contact lens wear in children, the investigators will know if multifocal contact lenses slow or simply delay myopia progression, and the investigators will know whether myopia progression increases following discontinuation of soft multifocal contact lens wear. Answers to questions addressed by this proposal could improve care for 60 million myopic children in the United States. While the consequences of ordinary myopia are rarely sight-threatening, the quality of life for myopic patients is negatively affected and the health care costs to treat myopia are approximately 4.6 billion dollars in 1990 US dollars. The National Eye Institute recognizes the need to evaluate the efficacy of potential treatments for delaying the onset or for slowing the progression of myopia, such as lenses that alter peripheral defocus. The BLINK2 Study seeks to maximize benefit while lowering the risk of multifocal contact lens wear for myopia control while answering important scientific and clinical questions about the consequences and mechanism of myopia progression, a problem that affects many people in the United States.
Study Design
- Study Type
- Observational
- Observational Model
- Cohort
- Time Perspective
- Prospective
Eligibility Criteria
- Ages
- 10 Years to 15 Years (Child)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Participants in the BLINK Study
Exclusion Criteria
- Not provided
Arms & Interventions
Contact lens
The first two years of the study all participants will wear +2.50 D multifocal contact lenses. The last year of the study, all subjects will be wearing single vision contact lenses.
Intervention: Contact lenses (Device)
Outcomes
Primary Outcomes
The statistical correlation between choroidal thickness and axial length
Time Frame: Three years
test the hypothesis that thinner subfoveal choroidal thickness (a layer of blood vessels) is associated with greater axial elongation (eye growth)
The statistical correlation between iPRGC activity and axial length
Time Frame: Three years
test the hypothesis that less ipRGC activity (cells in the back of the eye as measured by blue light-driven inputs to the pupil response) is associated with greater axial elongation (eye growth)
The statistical correlation between Light levels and axial length
Time Frame: Three years
test the hypothesis that exposure to lower light levels is associated with greater axial elongation (eye growth)
The Statistical Correlation Between Three-year Change in Choroidal Thickness and Three-year Change in Axial Length
Time Frame: Three years
test the hypothesis that thinner subfoveal choroidal thickness (a layer of blood vessels) is associated with the outcome of greater axial elongation (eye growth) The hypothesis relates to the two years of multifocal contact lens wear and one year of single vision contact lens wear. As such, it uses the entire sample which experiences the same contact lens wear in the BLINK2 Study.
The Statistical Correlation Between iPRGC Activity at BLINK2 Baseline and Three-year Change in Axial Length
Time Frame: Three years
test the hypothesis that less ipRGC activity (cells in the back of the eye as measured by blue light-driven inputs to the pupil response - measured by the blue decay coefficient) as measured at the Baseline BLINK 2 is associated with greater axial elongation (eye growth) over three years The hypothesis relates to the two years of multifocal contact lens wear and one year of single vision contact lens wear. As such, it uses the entire sample which experiences the same contact lens wear in the BLINK2 Study.
The Statistical Correlation Between Light Levels Measured at Baseline and Three-year Change in Axial Length
Time Frame: Three years
test the hypothesis that exposure to light levels over 1000 lux as measured at the Baseline BLINK2 visit is associated with less axial elongation (eye growth) over three years The hypothesis relates to the two years of multifocal contact lens wear and one year of single vision contact lens wear. As such, it uses the entire sample which experiences the same contact lens wear in the BLINK2 Study.
Three-year Choroidal Thickness Change
Time Frame: 3 years
The three-year change from baseline to three years for choroidal thickness.
Duration of Exposure to Light Levels Exceeding 1000 Lux at Baseline
Time Frame: Baseline
Baseline light exposure as measured by minutes at light levels over 1000 lux. Light exposure was monitored using the Actiwatch2 (Phillips Respironics), a light-sensing and logging watch worn on the wrist. Participants wore the device for a 1 week period to monitor environmental light exposure. The illuminance was measured in lux every minute. Data were scrubbed of periods where the watch was not worn or other artifacts. Light levels over 1000 lux were added to determine time outdoors in minutes.
Baseline iPRGC Activity
Time Frame: Baseline
Baseline iPRGC activity (cells in the back of the eye as measured by blue light-driven inputs to the pupil response - measured by the blue decay coefficient). The Blue Decay Coefficient represents the rate at which the pupil redilates in the dark after exposure to multiple 5-second pulses of red and blue light. The redilation data are fit by an exponential decay function eβt where t is time in seconds and the coefficient β is the natural log of the percent change in pupil diameter per second. Values range from -0.30 to -0.01. More positive values represent slower pupil redilation and are associated with greater, potentially beneficial ipRGC activity.
Secondary Outcomes
- Accommodative amplitude(Two years)
- Lag of accommodation(Two years)
- Accommodative facility(Two years)
- Rebound of progression(One year)
- Slowing of myopia progression(Two years)
- Accommodative Amplitude(Baseline)
- Lag of Accommodation(Baseline)
- Accommodative Facility(Baseline)
- Slowing of Myopia Progression - Axial Length(Two year change (Baseline to 2-Year visit))
- Rebound of Progression - Axial Length(One year change (2-year visit to 3-year visit))
- Rebound of Progression - Myopia Progression(One year change (2-year visit to 3-year visit))
- Slowing of Myopia Progression - Myopia Progression(Two year change (Baseline visit to 2-year visit))
Investigators
Jeffrey J. Walline, OD PhD
Principal Investigator
Ohio State University