Use of the Visumax™ Femtosecond Laser

• Effectiveness- Predictability [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  Decrease in manifest refraction spherical equivalent (MRSE) to within ± 1.00 D and ± 0.50 D of the intended refractive outcome at the point at which stability is first reached. A minimum of 75% of eyes should have an achieved refraction within ± 1.00 D of the intended outcome, and at least 50% of eyes should be within ± 0.50D of the intended outcome.
  
  
• Effectiveness- Improvement in UCVA following treatment [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  A minimum of 85% of eyes targeted for emmetropia should have uncorrected visual acuity of 20/40 or better at the postoperative interval at which stability has been established.
  
  
• Stability Criteria- Three of the four stability criteria from ANSI Z80.11-2007 are required [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  At least 95% of the treated eyes should have a change ≤ 1.00 D of MRSE at the latter of two postoperative refractions performed at least 3 months apart or at 3 months after surgery when compared with the 1-month interval.
  
  
• Stability Criteria- Three of the four stability criteria from ANSI Z80.11-2007 are required [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  The mean rate of change in MRSE, as determined by paired analysis, is ≤ 0.5 D per year (0.04 D/month) over the same time period.
  
  
• Stability Criteria- Three of the four stability criteria from ANSI Z80.11-2007 are required [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  The mean rate of change of MRSE decreases monotonically over time, with a projected asymptote of zero or a rate of change attributable to normal aging.
  
  
• Stability Criteria- Three of the four stability criteria from ANSI Z80.11-2007 are required [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  The 95% confidence interval for the mean rate of change includes zero or a rate of change attributable to normal aging.
  
  
• Safety- Preservation of Best-Spectacle Corrected Visual Acuity (BSCVA) [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  1. In eyes with preoperative BSCVA 20/20 or better, < 1% worse than 20/40 at the postoperative interval at which stability has been established
  2. < 5% of eyes with BCVA loss ≥ 2 lines
  
  
• Safety- Induced manifest refractive astigmatism [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  < 5% of eyes with > 2.00 D cylinder at the postoperative interval at which stability has been established
  
  
• Safety- Incidence of Adverse Events [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  < 1% of eyes for each type of adverse event
  
  
• Safety- Contrast Sensitivity [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  Mean of "within-eye" loss of contrast sensitivity from baseline to 12 months will be provided with the 1-sided 95% confidence interval for each spatial frequency. Percentage of eyes showing ≥ 0.3 log units loss at two or more spatial frequencies will be calculated.
  
  

• Safety- Patient Symptoms [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  Will be considered as a secondary safety variable
  
  

This is a prospective multi-center clinical trial in which a total of 360 eyes of consecutive subjects will be enrolled, treated with the VisuMax™ Femtosecond Laser, and followed for a 12-month period. The study will be conducted at up to 8 clinical sites.

Enrollment will be phased such that 100 eyes will be initially enrolled and followed. When 50 of the initial eyes have reached the 3-month follow-up exam, an interim clinical study report will be submitted to FDA along with a request to continue enrollment up to 360 eyes.

Subjects will be screened for eligibility, and informed consent will be obtained from those who meet screening criteria and are interested in participating in the study. Eligible subjects will be examined preoperatively to obtain a medical history and to establish a baseline ocular condition. Baseline and postoperative measurements will include manifest refraction, cycloplegic refraction, distance visual acuity (best corrected and uncorrected), slit-lamp examination, fundus examination, corneal topography, central corneal pachymetry, mesopic pupil measurement, wavefront analysis, mesopic contrast sensitivity, and intraocular pressure (IOP).