Fitting Evaluation of Hydrogel and Silicone Hydrogel Sphere Design Contact Lenses

Fitting Evaluation of Hydrogel and Silicone Hydrogel Sphere Design Contact Lenses.

The aim of this non-dispensing fitting study is to evaluate the short term lens fit, vision performance of three monthly replacement sphere lenses.

This is a 40-subject, double masked, randomized, bilateral, non-dispensing fitting trial comparing hydrogel and silicone hydrogel lens materials. 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 each pair bilaterally in a series of three short fitting comparisons.

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 CL (Contact Lens) wearer who is not wearing any of the study lenses.
  • Has a CL spherical prescription between - 1.00 and - 6.00 (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:

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

  • 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 - 6.00D

  • 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.