Astigmatism
Conditions
Keywords
astigmatism, contact lens, driving
Brief summary
Small amounts of astigmatism are often uncorrected in contact lens wearers. The effect with respect to driving is unknown, but it could threaten safe operation of a motor vehicle, especially under conditions such as nighttime driving when visual abilities are highly challenged. This study measures driving-specific visual abilities and simulated driving performance in participants with astigmatism who either have or do not have their astigmatism corrected. The primary hypothesis is that at a tactical level, contact lenses correcting for astigmatism will result in safer driving performance overall. The secondary hypothesis is that at an operational level, contact lenses correcting for astigmatism will result in better driving-specific visual performance.
Detailed description
Safe driving relies heavily on good vision. Good vision while driving relates to multiple abilities, such as dynamic visual acuity, contrast sensitivity, management of glare and peripheral vision, etc. While spherical contact lenses address issues of correction of visual acuity as determined by forward static vision tests, if they do not provide visual acuity both immediately and smoothly with eye movement then vision can be compromised. Glare can be a problem as well when contact lenses are off center. Fluctuating vision as a result of lens movement on the eye could be especially problematic and frustrating for patients who have astigmatism. Furthermore, experiencing moments of blurred vision no matter how brief can be potentially hazardous while driving. The 1\*DAY ACUVUE® MOIST for ASTIGMATISM contact lenses have a unique blink-activated stabilization system to prevent rotation of the lens on the eye, and may have significant visual advantages for drivers with astigmatism. These lenses provide continuous corrected acuity compared to non-ballasted contact lenses, and thus are potentially safer for driving. Contact comparison will consist of 1\*DAY ACUVUE® MOIST (spherical control) versus 1\*DAY ACUVUE® MOIST for ASTIGMATISM (the daily disposable astigmatism alternative). The study will investigate the potential advantages of contact lenses specifically designed to correct for astigmatism, compared to similar correction with spherical contacts, for adult licensed drivers with astigmatism, employing a double-blind (subjects and research assistant blind to hypotheses), randomized, cross-over design (spherical, vs. astigmatism contacts). This will be a multi-stage study comprised of the following: Preliminary study to determine the likelihood of detecting a significant difference between the standard spherical and astigmatism contacts in a full Randomize Clinical Trial (n=12; data and power analysis)
Interventions
OTHERNo contact lenses
simulated driving tests
DEVICE1-DAY ACUVUE® MOIST contact lenses
spherical contact lenses worn during simulated driving tests
DEVICE1-DAY ACUVUE® MOIST for ASTIGMATISM contact lenses
toric contact lenses worn during simulated driving tests
Sponsors
Johnson & Johnson Vision Care, Inc.
University of Virginia
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Masking description
participants and research assistant blind to hypothesis
Eligibility
Sex/Gender
ALL
Age
18 Years to 39 Years
Healthy volunteers
Yes
Inclusion criteria
* Adult licensed drivers between the ages of 18-39, similar number of males and females will be studied who meet the following inclusion criteria: * Bilateral corrected vision of 20/40 or better * Bilateral astigmatism between 0.75 to 2.0 diopters, with spherical correction from -1 to -6 * No active eye infection * No defective peripheral vision * Do not have correction for bifocals * Routinely wear contact lenses more than 4 times per week * Routinely drive a car more than 4 times week * Do not have a history of motion, sea or big screen (e.g. IMAX) sickness or experience persistent Simulation Adaptation Syndrome
Exclusion criteria
* Bilateral corrected vision of worse than 20/40 * No astigmatism * Active eye infection * Defective peripheral vision * Wear bifocals * Wears contact lenses less than 4 times per week * Drives infrequently (less than 4 times per week)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Tactical Composite Score | 1 day laboratory study | Z-score composite of tactical testing outcomes |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Operational Composite Score | 1 day laboratory study | Z-score composite of operational testing outcomes |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Contact Lens Sequence Order in which each participant received the 3 lens conditions | 11 |
| Total | 11 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 | FG003 | FG004 | FG005 |
|---|---|---|---|---|---|---|---|
| Overall Study | Withdrawal by Subject | 2 | 0 | 0 | 0 | 0 | 0 |
Baseline characteristics
| Characteristic | Contact Lens Sequence |
|---|---|
| Age, Continuous | 22.2 years STANDARD_DEVIATION 4.6 |
| Region of Enrollment United States | 11 participants |
| Sex: Female, Male Female | 2 Participants |
| Sex: Female, Male Male | 9 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 11 |
| serious Total, serious adverse events | 0 / 11 |
Outcome results
Primary
Tactical Composite Score
Z-score composite of tactical testing outcomes
Time frame: 1 day laboratory study
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Contact Lens Rx | Tactical Composite Score | None | -1.73 Z score | Standard Deviation 3.53 |
| Contact Lens Rx | Tactical Composite Score | Sphere | 0.19 Z score | Standard Deviation 2.62 |
| Contact Lens Rx | Tactical Composite Score | Toric | 1.54 Z score | Standard Deviation 1.75 |
Secondary
Operational Composite Score
Z-score composite of operational testing outcomes
Time frame: 1 day laboratory study
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Contact Lens Rx | Operational Composite Score | None | -2.77 Z score | Standard Deviation 4.3 |
| Contact Lens Rx | Operational Composite Score | Sphere | 1.37 Z score | Standard Deviation 2.37 |
| Contact Lens Rx | Operational Composite Score | Toric | 1.40 Z score | Standard Deviation 2.65 |