Corneal and Conjunctival Sensitivity and Staining Study

The primary objective of this study is to compare subjective symptoms and ocular health in a group of individuals who are currently wearing soft contact lenses on a daily wear basis, after a short period of no lens wear and during the time course when using differing care regimens. Observations will be made to monitor physiology.

Inclusion criteria

An eligible participant is one who:

• Is between 17-45 years old and has full legal capacity to volunteer.
• Has read and signed an information consent letter, after having the opportunity to ask questions and receive acceptable answers.
• Is willing and able to follow instructions and maintain the appointment schedule.
• Does not experience any dryness related symptoms during lens wear (i.e. at least 12 hours of comfortable wearing time)
• Is correctable to a visual acuity of 6/7.5 (20/25) or better (each eye) with their habitual vision correction.
• Has normal binocular vision (no strabismus, no amblyopia).
• Has clear corneas and no active ocular disease.
• Has had an ocular examination in the last two years. Has a distance contact lens prescription between +0.50D to +6.00 DS and -0.50D and -12.00 DS.
• Has astigmatism less than or equal to -1.00DC.
• Agrees to wear the study lenses on a daily wear basis.
• Has a pair of glasses with updated prescription and agrees to wear them during the period no lens wear (7-10 days) as required by the study.

Exclusion criteria

A person is ineligible if he/she:

• Has undergone corneal refractive surgery.
• Is aphakic.
• Has any active ocular disease.
• Has any systemic disease affecting ocular health.
• Is using any systemic or topical medications that may affect ocular health.
• Has a known sensitivity to the diagnostic pharmaceuticals to be used in the study.
• Is pregnant or lactating.
• Is participating in any other clinical or research study.
• Has a known clinically significant sensitivity to the contact lens care solutions used in the study.
• Has ocular or systemic allergies that could adversely affect contact lens wear.
• Currently wears lenses on a continuous or extended wear basis.
• Has any ocular pathology or severe insufficiency of lacrimal secretion (dry eyes) that would affect the wearing of contact lenses.
• Has pinguecula/pterygium that, in the investigator's judgment, makes contact lens wear inadvisable.
• Is a rigid lens wearer.
• Has corneal staining graded as 2 (macropunctate) or greater in any corneal region in either eye, sum of corneal staining type (severity) of greater than or equal to 4 across the entire cornea in either eye, or any corneal staining covering greater than or equal to 20% in any corneal region in either eye.