Performance of Toric Silicone Hydrogel Contact Lenses

Performance of Two Toric Silicone Hydrogel Contact Lenses

The purpose of this study was to evaluate the clinical performance and subjective lens handling (insertion and removal) of two toric silicone hydrogel contact lenses after one month of daily wear each.

This was a prospective, randomized, double masked, bilateral, crossover study. Participants were expected to attend 6 scheduled visits over a period of approximately 2 months.

Inclusion Criteria:

A person is eligible for inclusion in the study if he/she:

• Is between 18 and 40 years of age (inclusive)
• Has had a self-reported visual exam in the last two years
• Is an adapted soft contact lens wearer
• Is not a habitual wearer of either study lens
• Has a contact lens spherical prescription between +4.00 to - 10.00 (inclusive). Best corrected visual acuity of 20/30 or better in either eye
• Have contact lens prescription of no less than -0.75D of astigmatism and no more than -2.25 D in both eyes.
• Can achieve best corrected spectacle distance visual acuity of 20/25 (0.10 logMAR) or better in each eye.
• Can achieve a distance visual acuity of 20/30 (0.18 logMAR) or better in each eye with the study contact lenses.
• Has clear corneas and no active ocular disease
• Has read, understood and signed the information consent letter.
• Patient contact lens refraction should fit within the available parameters of the study lenses.
• Is willing to comply with the wear schedule (at least 5 days per week, > 8 hours/day assuming there are no contraindications for doing so).
• Is willing to comply with the visit schedule

Exclusion Criteria:

A person will be excluded from the study if he/she:

• A person was excluded from the study if he/she:
• Has a CL prescription outside the range of the available parameters of the study lenses.
• Has a spectacle cylinder less than -0.75D or more than -2.50 D of cylinder in either eye.
• Has a history of not achieving comfortable CL wear (5 days per week; > 8 hours/day)
• Has contact lens best corrected distance vision worse than 20/25 (0.10 logMAR) in either eye.
• Presence of clinically significant (grade 2-4) anterior segment abnormalities
• Presence of ocular or systemic disease or need of medications which might interfere with contact lens wear.
• Slit lamp findings that would contraindicate contact lens wear such as:
• Pathological dry eye or associated findings
• Pterygium, pinguecula, or corneal scars within the visual axis
• Neovascularization > 0.75 mm in from of the limbus
• Giant papillary conjunctivitis (GCP) worse than grade 1
• Anterior uveitis or iritis (past or present)
• Seborrheic eczema, Seborrheic conjunctivitis
• History of corneal ulcers or fungal infections
• Poor personal hygiene
• Has a known history of corneal hypoesthesia (reduced corneal sensitivity)
• Has aphakia, keratoconus or a highly irregular cornea.
• Has Presbyopia or has dependence on spectacles for near work over the contact lenses.
• Has undergone corneal refractive surgery.
• Is participating in any other type of eye related clinical or research study.