Astigmatism
Conditions
Brief summary
The purpose of this study is to determine the benefits of fitting low astigmats with soft toric contact lenses versus spherical contact lenses with regard to visual comfort, eyestrain, fitting efficiency, and visual performance.
Interventions
Soft contact lens to be worn in a daily wear, daily disposable modality for one week
Soft contact lens to be worn by participants in a daily wear, daily disposable modality for one week.
Sponsors
Study design
Eligibility
Inclusion criteria
1. The subject must have read, understand, and sign the statement of informed consent and receive a fully executed copy of the Informed Consent Form. 2. The subject must appear able and willing to adhere to the instructions set forth in this protocol. 3. The subject must be between 18 years and 45 years of age (inclusive). 4. The subject must have best-corrected Snellen visual acuity of 20/30 or better in each eye. 5. If the subject has ever worn contact lenses, the subject must be a current wearer of soft spherical contact lenses for at least 5 days/week and at least 8 hours/day during the month prior to enrollment. 6. Subjective refraction must result in a vertex-corrected astigmatic contact lens prescription requiring at least -0.75 DC but not more than -1.75 DC cylindrical contact lens correction in each eye. 7. Subjective refraction must result in a vertex-corrected spherical contact lens prescription between +0.25D to +4.00D or between-0.50D to -9.00D in each eye. 8. The subject must not have the need for presbyopic correction (i.e., they must not be using as add in spectacles or wearing multifocal or monofocal contact lenses). 9. The subject must have normal eyes with no evidence of abnormality or disease that in the opinion of the investigator would contraindicate contact lens wear. 10. The subject must have access to the internet throughout the day (either desktop and/or smartphone) and be willing to answer a web-based survey within 1 hour of receiving a text message based notification throughout the day for up to 8 days, throughout the study duration.
Exclusion criteria
1. Self-reported current pregnancy or lactation or plans to become pregnant during the study period (subjects who report becoming pregnant during the study will be discontinued) 2. Any previous ocular or intra-ocular surgery (e.g. radial keratotomy, PRK, LASIK, etc.) 3. Any clinically meaningful slit lamp findings contraindicating contact lens wear (e.g. greater than or equal to grade 3 finding of edema, corneal neovascularization, corneal staining, conjunctival injection, blepharitis/meibomian gland dysfunction) on the FDA classification scale or any other ocular abnormality that in the opinion of the investigator may contraindicate contact lens wear. 4. Any ocular infection 5. Current use of topical ophthalmic medications other than artificial tears/rewetting drops. 6. History of binocular vision abnormality or strabismus. 7. Any infectious disease (e.g. hepatitis, tuberculosis) or a contagious immunosuppressive disease (e.g. HIV) by self-report. 8. Other active ocular disease that in the opinion of the investigator would contraindicate contact lens wear. 9. Employee of the investigational clinic (e.g. investigator, coordinator, technician) 10. Subject does not have a wearable pair of spectacles.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Objective Comfort Assessed by Electromyography(EMG) | 1 week | Electromyography (EMG) utilizes electrodes affixed to the skin below the eyelid, which measures activity of the orbital portion of the orbicularis oculi muscle. The orbital portion of the orbicularis oculi muscle pulls on the skin of the forehead, temple and cheek and draws it toward a point at the edge of the orbit. This part of the muscle is mainly under voluntary control, and it what is contracted during the process of squinting. The palpebral portion of this muscle closes the eyelids. The EMG reading was performed while the subject was wearing contact lenses in order to objectively assess eyestrain.The higher the EMG reading indicated the more the eyestrain. The original EMG data collected from a 40-second recording consisted of approximately 40,000 observations; the machine read about 1000 observations per second consecutively during 40-second recording. The original EMG reading was converted to a single data point and entered in the EDC for the analysis purpose. |
| Visual Comfort | 1-week follow-up | The Visual comfort (diurnal fluctuation\[DF\]) scores were derived from the National Eye Institute Refractive Error Quality of Life (NEI-RQL) instruments- specifically the diurnal fluctuations sub-scale, by following the instruction given in the NEI-RQL-42 User Manual, Version 1.0. The NEI-RQL is a validated patient reported outcome questionnaire to assess the impact of refractive correction on vision specifically to quality of life. This survey consisted of 42 items used to develop 13 subscales: clarity of vision, expectations, near vision, far vision, diurnal fluctuations, activity limitations, glare, symptoms, dependence on correction, worry, suboptimal correction, appearance, and satisfaction with correction. An overall score is calculated by averaging the subscales. The overall scores can take on values of 0 to 100. Higher scores indicate better outcomes |
Countries
United States
Participant flow
Recruitment details
A total of 159 subjects were enrolled in the study. Of the enrolled subjects 45 did not meet the eligibility criteria and 114 subjects were dispensed a study lens. Of the dispensed subjects 10 subjects were discontinued and 94 subjects completed the study.
Pre-assignment details
Of those completed 24 were excluded from the analysis due to a major protocol deviation. Of the subjects that completed all study visits without a major protocol deviation, 10 subjects were classified as neophytes and 60 as habitual contact lens users.
Participants by arm
| Arm | Count |
|---|---|
| Dispensed Subjects All subjects that were dispensed at least one study lens. | 114 |
| Total | 114 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Period 1 | Lost to Follow-up | 0 | 3 |
| Period 1 | No longer meets Eligibility Criteria | 0 | 2 |
| Period 1 | Physician Decision | 1 | 0 |
| Period 1 | Unsatisfactory Lens Fit | 1 | 0 |
| Period 1 | Unsatisfactory Visual Response | 1 | 0 |
| Period 2 | Lens Discomfort | 1 | 0 |
| Period 2 | Unsatisfactory Lens Fit | 1 | 0 |
Baseline characteristics
| Characteristic | Dispensed Subjects |
|---|---|
| Age, Continuous Habitual Users | 26.9 years STANDARD_DEVIATION 4.93 |
| Age, Continuous Neophtyes | 28.5 years STANDARD_DEVIATION 2.66 |
| Age, Continuous Overall | 27.1 years STANDARD_DEVIATION 4.77 |
| Race/Ethnicity, Customized American Indian or Alaska Native | 3 participants |
| Race/Ethnicity, Customized Asian | 34 participants |
| Race/Ethnicity, Customized Black or African American | 18 participants |
| Race/Ethnicity, Customized Native Hawaiian or Pacific Islander | 2 participants |
| Race/Ethnicity, Customized Other | 8 participants |
| Race/Ethnicity, Customized White | 49 participants |
| Region of Enrollment United States | 114 participants |
| Sex: Female, Male Female | 75 Participants |
| Sex: Female, Male Male | 39 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 114 | 0 / 114 |
| serious Total, serious adverse events | 0 / 114 | 0 / 114 |
Outcome results
Objective Comfort Assessed by Electromyography(EMG)
Electromyography (EMG) utilizes electrodes affixed to the skin below the eyelid, which measures activity of the orbital portion of the orbicularis oculi muscle. The orbital portion of the orbicularis oculi muscle pulls on the skin of the forehead, temple and cheek and draws it toward a point at the edge of the orbit. This part of the muscle is mainly under voluntary control, and it what is contracted during the process of squinting. The palpebral portion of this muscle closes the eyelids. The EMG reading was performed while the subject was wearing contact lenses in order to objectively assess eyestrain.The higher the EMG reading indicated the more the eyestrain. The original EMG data collected from a 40-second recording consisted of approximately 40,000 observations; the machine read about 1000 observations per second consecutively during 40-second recording. The original EMG reading was converted to a single data point and entered in the EDC for the analysis purpose.
Time frame: 1 week
Population: Analysis population consists of all subjects that completed all study visits without a major protocol deviation.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Etafilcon A | Objective Comfort Assessed by Electromyography(EMG) | Habitual Users, N=60, N=60 | 0.082 volts | Standard Deviation 0.1239 |
| Etafilcon A | Objective Comfort Assessed by Electromyography(EMG) | Neophytes, N=10, N=10 | 0.085 volts | Standard Deviation 0.094 |
| Etafilcon A for Astigmatism | Objective Comfort Assessed by Electromyography(EMG) | Habitual Users, N=60, N=60 | 0.047 volts | Standard Deviation 0.0599 |
| Etafilcon A for Astigmatism | Objective Comfort Assessed by Electromyography(EMG) | Neophytes, N=10, N=10 | 0.257 volts | Standard Deviation 0.631 |
Visual Comfort
The Visual comfort (diurnal fluctuation\[DF\]) scores were derived from the National Eye Institute Refractive Error Quality of Life (NEI-RQL) instruments- specifically the diurnal fluctuations sub-scale, by following the instruction given in the NEI-RQL-42 User Manual, Version 1.0. The NEI-RQL is a validated patient reported outcome questionnaire to assess the impact of refractive correction on vision specifically to quality of life. This survey consisted of 42 items used to develop 13 subscales: clarity of vision, expectations, near vision, far vision, diurnal fluctuations, activity limitations, glare, symptoms, dependence on correction, worry, suboptimal correction, appearance, and satisfaction with correction. An overall score is calculated by averaging the subscales. The overall scores can take on values of 0 to 100. Higher scores indicate better outcomes
Time frame: 1-week follow-up
Population: The analysis population consists of all subjects that completed all study visits without a major protocol deviation.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Etafilcon A | Visual Comfort | Habitual Users, N=60, N=60 | 72.8 units on a scale | Standard Deviation 24.94 |
| Etafilcon A | Visual Comfort | Nepohytes, N=10, N=10 | 70.4 units on a scale | Standard Deviation 21.29 |
| Etafilcon A for Astigmatism | Visual Comfort | Habitual Users, N=60, N=60 | 80.6 units on a scale | Standard Deviation 19.41 |
| Etafilcon A for Astigmatism | Visual Comfort | Nepohytes, N=10, N=10 | 72.5 units on a scale | Standard Deviation 23.02 |