Daytime Corneal Swelling During Wear of Narafilcon B Lenses

Not Applicable

Completed

Interventions: Device: Polymacon
Device: Lotrafilcon A
Other: Spectacles
Device: narafilcon B

Brief Summary: The purpose of this research is to measure daytime open-eye response to wearing of narafilcon B lenses.

Recruitment & Eligibility

Inclusion Criteria

Be of legal age (i.e. ≥ 18 years).
Be mentally competent, willing and able to sign a written informed consent form.
Have contact lens distance sphere requirement in the range -1.00D to -6.00D.
Have spectacle astigmatism <1.25D in each eye.
Currently wear soft contact lenses (for at least 6 months prior to the trial) with documentation of current prescription.
Have normal eyes with no evidence of abnormality or disease. For the purpose of this study a normal eye is defined as one having: i) no evidence of lid abnormality or infection; ii) no conjunctival abnormality or infection; iii) no clinically significant slit lamp findings (i.e, edema, staining, scarring, vascularization, infiltrates or abnormal opacities); iv) no other active ocular disease.

Exclusion Criteria

Required concurrent ocular medication.
Any systemic illness which would contra-indicate lens wear or the medical treatment of which would affect vision or successful lens wear.
Eye injury or surgery within eight weeks immediately prior to enrollment for this study.
Abnormal lacrimal secretions.
Pre-existing ocular irritation that would preclude contact lens fitting.
Keratoconus or other corneal irregularity.
Pregnancy, lactating or planning a pregnancy at the time of enrollment.
Participation in any concurrent clinical trial.

Arm && Interventions

Group	Intervention	Description
polymacon	Polymacon	Assigned in random order during one of four 8 hour sessions on four separate days, in one of 24 possible order combinations.
lotrafilcon A	Lotrafilcon A	Assigned in random order during one of four 8 hour sessions on four separate days, in one of 24 possible order combinations.
Spectacles No Lenses	Spectacles	Assigned in random order during one of four 8 hour sessions on four separate days, in one of 24 possible order combinations.
narafilcon B	narafilcon B	Assigned in random order during one of four 8 hour sessions on four separate days, in one of 24 possible order combinations.

Primary Outcome Measures

Name	Time	Method
Corneal Thickness	After 8 hours of contact lens wear	Percentage of corneal swelling (positive value) or deswelling (negative value) measured with Haag-Streit pachymetry equipment in microns, reported as a percent.
Endothelial Blebs	baseline, after 20 minutes of treatment conditions	Corneal images captured with equipment are measured, manually outlined to estimate total bleb area from 0 to 100%. This is measured as a change in percentage after 20 minutes compared to the value prior to lens wear (baseline).
Limbal Redness	Baseline, After 8 hours of treatment conditions	Scale of 0 to 4, where 0=none and 4= severe redness. Measure reported as a comparison of 8 hours of wear to baseline with the difference being reported.