Safety and Effectiveness of Arcuate Incisions Performed With the iFS Femtosecond Laser System
Condition: Corneal Astigmatism
MeSH terms: Astigmatism
Intervention: iFS Femtosecond Laser System
Intervention description: arcuate incisions placed with the iFS femtosecond laser
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 40.0
Sex: All
Minimum age: 21 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: astigmatism

Summary:

      To determine if arcuate incisions performed with the iFS femtosecond laser are safe and
      effective in reducing corneal astigmatism.
    

Eligibility criteria:

        Inclusion Criteria:

          1. Male or female, of any race, and at least 21 years of age at the time of pre-op exam

          2. Corneal astigmatism, as determined by topographic keratometry, of 0.75 D to 4.00
             diopters (D)

          3. Best Spectacle Corrected Distance Visual Acuity (BSCVA)

               1. Group 1:

                    -  Natural astigmatism, no cataract - BSCVA of 20/25 or better

                    -  Pre cataract or phakic IOL surgery - no BSCVA criteria

               2. Group 2:

                    -  Post IOL surgery- BSCVA of 20/25 or better

          4. Uncorrected Visual Acuity (UCVA) of 20/40 or worse

          5. Demonstration of agreement: Corneal astigmatism (as determined by topographic
             keratometry) must be in agreement with refractive astigmatism (as determined by
             manifest refractions) within </= 0.75 D in magnitude and 15 degrees axis when cylinder
             </= 1.5 D or 10 degrees axis when cylinder > 1.5 D.

          6. Preoperative central pachymetry of >/=480 um

          7. Keratometry between 38.0 D (flat) to 48.0 D (steep)

          8. Corneal power (diopters) difference at the 3mm point from topographic center shall be
             </= 1D at the steepest meridian

          9. Intraocular pressure of 12 to 21 mm Hg with no glaucomatous retinal/optic nerve
             changes

         10. Subjects who have worn a contact lens within the past 30 days must remove the soft
             lens at least 2 weeks prior and a rigid or toric lens at least 3 weeks prior to
             baseline measurements

         11. Willing and capable of returning for follow-up examinations for the duration of the
             study

        Exclusion Criteria:

          1. Angle kappa of greater than 0.5 mm, absolute value

          2. Prior implantation of toric or multifocal intraocular lens

          3. Women who are pregnant, breast-feeding, or intend to become pregnant over the course
             of the study

          4. Concurrent use of topical or systemic medications that may impair corneal wound
             healing

          5. History of any ocular or medical conditions that could affect corneal wound healing

          6. History of active or recurrent ophthalmic disease, including corneal dystrophy or
             other non-refractive abnormality such as exposure keratitis or clinically significant
             dry eye

          7. Abnormal topography, including evidence of keratoconus or pellucid marginal
             degeneration in either eye

          8. Evidence of clinically significant corneal opacity/scar in the operative eye(s) within
             an 8 mm diameter zone of the visual axis

          9. Known sensitivity or inappropriate responsiveness to any of the medications used in
             the post-operative course

         10. Participation in any other conflicting clinical study