The Clinical Comparison of Senofilcon A and Stenfilcon A Contact Lenses

The purpose of this bilateral cross-over study is to evaluate the clinical performance of senofilcon A lens with the stenfilcon A lens. In particular, the study will focus on ocular physiology, lens fit, lens surface, visual acuity, and subjective response.

Inclusion criteria

Subjects will only be eligible for the study if:

• They are of legal age (18) and capacity to volunteer.
• They understand their rights as a research subject and are willing and able to sign a Statement of Informed Consent.
• They are willing and able to follow the protocol.
• They agree not to participate in other clinical research for the duration of this study.
• They have a contact lens spherical prescription between -1.00 to - 6.00D (inclusive)
• They have a spectacle cylindrical correction of -0.75D or less in each eye.
• At dispensing, they can attain at least 0.10 logMAR distance high contrast visual acuity in each eye with the study lenses within the available power range.
• They currently use soft contact lenses or have done so in the previous six months.
• They are willing to comply with the wear schedule (at least six days per week and for at least eight hours per day).

Exclusion criteria

Subjects will not be eligible to take part in the study if:

• They have an ocular disorder which would normally contra-indicate contact lens wear.
• They have a systemic disorder which would normally contra-indicate contact lens wear.
• They are using any topical medication such as eye drops or ointment.
• They have had cataract surgery.
• They have had corneal refractive surgery.
• They have any corneal distortion resulting from previous hard or rigid lens wear or have keratoconus.
• They are pregnant or lactating.
• They have any ocular abnormality which would, in the opinion of the investigator, normally contraindicate contact lens wear.
• They have any infectious disease which would, in the opinion of the investigator, contraindicate contact lens wear or pose a risk to study personnel; or they have any immunosuppressive disease (e.g. HIV), or a history of anaphylaxis or severe allergic reaction.
• They have taken part in any other contact lens or care solution clinical trial or research, within two weeks prior to starting this study.
• They currently wear either MyDay (daily) or the Acuvue Oasys (2 weekly) lens.