Comparison of Two Soft Bifocal Contact Lenses

Study Overview
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Brief Summary
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The purpose of the study is to compare the visual performance of two soft bifocal contact lenses.

Conditions
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Presbyopia

Intervention / Treatment
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* Device: balafilcon A
* Device: senofilcon A


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The subject must between 35 and 70 years of age. The subject must have presbyopic symptoms or be already wearing presbyopic contact lens correction. The subject's spherical equivalent distance refraction must be in the range of -1.00 to -6.00 or -9.00 to -10.00 in each eye. Refractive cylinder must be -0.75 D in each eye. The subject must have an ADD power of +0.75D to +2.50D in each eye. The subject must have best corrected visual acuity of 20/20-3 or better in each eye The subject's must have at least 20/30-distance vision OU with the study contact lenses. The subject must agree that they are comfortable with their vision prior to being dispensed the study lenses The subject must be an adapted soft contact lens wearer in both eyes. The subject must appear able and willing to adhere to the instructions set forth in this clinical protocol. The subject must read and sign the STATEMENT OF INFORMED CONSENT and be provided a copy of the form. Exclusion Criteria: Ocular or systemic allergies or disease that may interfere with contact lens wear. Systemic disease, autoimmune disease or use of medication, which may interfere with contact lens wear. Clinically significant (grade 3 or 4) corneal edema, corneal vascularization, corneal staining or any other abnormality of the cornea, which may contraindicate contact lens wear Clinically significant (grade 3 or 4) tarsal abnormalities that might interfere with contact lens wear. Any ocular infection. Any corneal distortion resulting from previous hard or rigid gas permeable contact lens wear. Pregnancy or lactation Any infectious disease (e.g., hepatitis, tuberculosis) or an immunosuppressive disease (e.g., HIV). History of diabetes History of binocular vision abnormality or strabismus

Ages Eligible for Study
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Minimum Age: 35 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: senofilcon A / balafilcon A<br>senofilcon A multifocal lenses worn first, balafilcon A multifocal lenses worn second | Device: balafilcon A<br>* multifocal contact lens<br>Device: senofilcon A<br>* multifocal contact lens<br>|
| Active Comparator: balafilcon A/senofilcon A<br>balafilcon A multifocal lenses worn first, senofilcon A multifocal lenses worn second | Device: balafilcon A<br>* multifocal contact lens<br>Device: senofilcon A<br>* multifocal contact lens<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Distance Visual Acuity | This outcome measures vision while subjects are looking at objects in the distance and is measures in logMARs.logMAR is the logarithm of the minimum angle of resolution.The ideal is 0.0 and represents 20/20 Snellen acuity.logMAR values >0.00 indicate vision poorer than ideal and values<0.0 indicate vision greater than ideal | after 1 week of wear | 
| Near Visual Acuity | This outcome measures vision while subjects are looking at objects near to them and is measured in logMARs. logMAR is the logarithm of the minimum angle of resolution.The ideal is 0.0 and represents 20/20 Snellen acuity.logMAR values >0.00 indicate vision poorer than ideal and values<0.0 indicate vision greater than ideal. | after 1 week wear | 
| Subject Vision | Subjects responded to How would you rate the overall quality of vision with these study contact lenses using the following scale: 1=poor, 2=fair, 3=good, 4=very good, 5=excellent. | after 1 week wear |