Clinical Performance of Hydrogel vs. Silicone Hydrogel Contact Lenses

Non-Dispensing Fitting Study Comparing the Clinical Performance of Hydrogel vs. Silicone Hydrogel Sphere Design Contact Lenses

The aim of this non-dispensing fitting study is to evaluate the subjective comfort, lens handling, lens fitting characteristics and visual acuity of different hydrogel lens designs versus silicone hydrogel lenses

This is a 60-subject, double masked, randomized, contra lateral, non-dispensing fitting trial comparing different lens materials (hydrogel vs silicone hydrogel). It is anticipated that this study will involve 2 visits, for each lens pair, as follows: Visits: V1 (lens dispensing), V2 (1 hour post lens settling). Each subject will be randomized to wear the test and control lenses in a series of three short fitting comparisons.

Inclusion Criteria:

• 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 CL (Contact Lens) wearer
• Has a CL spherical prescription between - 1.00 and - 10.00 (inclusive)
• Has a spectacle cylinder up to 0.75D (Diopter) in each eye.
• 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
• Is willing to comply with the visit schedule

Exclusion Criteria:

• Has never worn contact lenses before.

• Currently wears rigid gas permeable contact lenses.

• Has a history of not achieving comfortable CL wear (5 days per week; > 8 hours/day)

• Has a CL prescription outside the range of - 1.00 to -10.00D

• Has a spectacle cylinder ≥1.00D of cylinder in either eye.

• 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.