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6 continued from page 5 more intense need more treatment. This traditional classic pattern would undertreat those areas. Although traditional and Wave- front Optimized LASIK do a good job treating astigmatism, these are examples of how it could be better. CONTOURA Vision is superior to these options because it takes 22,000 different measurements of each cornea's topography, deter- mines where that patient's corneal astigmatism flares or tapers, and corrects it perfectly for that pattern. Every cornea is treated uniquely. It is not a cookie-cutter approach like we have had in the past. This is one reason why patients see better and have better optical quality with CONTOURA Vision than with tradi- tional LASIK. Case study A 32-year-old woman underwent LASIK on her left eye. Preoperative- ly, with her glasses, she could see 20/20. Her manifest refraction was –3.75 –0.50 x 55 correcting to 20/20. This was good vision, but CONTOU- RA Vision allows surgeons to take patients to the next level, beyond what they can see with glasses or contacts. Because CONTOURA Vi- sion can correct the corneal topog- raphy so perfectly, we can correct the optics more completely and take patients' vision beyond what is possible with glasses or contacts, both in quantity (Snellen acuity) and in quality. On the first day after CONTOURA Vision LASIK surgery, this eye could see 20/15 without any glasses or contacts, a full line beyond preop best corrected visual acuity. Three months later, this patient was 20/15+1, and her mani- fest refraction was perfect at plano sphere. Here's how it was done. The ablation profile in Figure 3 shows the small unique topograph- ical abnormalities on this cornea that CONTOURA Vision corrected. This is in addition to the customized myopic and astigmatic correction that was applied. The three purple areas are where CONTOURA Vision added more laser treatment and removed more tissue. This is the step that has never been done be- fore, and this is how we take LASIK surgery to the next level. Traditional LASIK and Wavefront Optimized LASIK don't treat these abnormali- ties, and these abnormalities have an effect on the way light is focused. They affect quality of vision. WaveLight Topolyzer VARIO, the topolyzer that Alcon has provided to use with CONTOURA Vision, allows for some advanced monitoring and analysis of each cornea. Surgeons can compare the preoperative and postoperative exams to see the changes that were made to the cornea. The top right image in Figure 4 is the patient's postopera- tive topography that was performed about 3 months after LASIK surgery. The bottom right is the preoperative exam. The blue image is the differ- ence between the two. This map highlights what CONTOURA Vision has done for this patient. Examining the preoperative map, the green arrow is pointing out a small but critical butterfly shaped abnormality directly in the center of the visual axis. Looking at the difference map, in the center of the patient's pupil is the butterfly wing pattern of tissue removal that underwent a small unique treat- ment. This would not have been done in traditional or Wavefront Optimized LASIK. Notice also the unique ablation at the 5:00 position (red arrow) just outside the pupil (denoted by the white and black circle). Here, CONTOURA Vision recognized that the cornea needed less treatment than in other areas. When the laser makes the cornea perfect on its anterior surface and corrects all of these small topo- graphic abnormalities, the optics are improved, and the eye is able to focus better than it was before. Higher order aberrations The Zywave wavefront analysis charts in Figure 5 show the patient's ocular higher order aberrations be- fore and after surgery. The preop- erative higher order aberrations are on the left. The gray bars represent averages for the United States' population, and the tan and blue represent the abnormalities present in this patient. Some of the signifi- cant higher order aberrations that affect vision quality are trefoil, qua- trefoil, and secondary astigmatism. At night, these three cause distor- tion and create glare, starbursting, and halo effects. When these are present, it changes the quality of the image that the patient sees. Before surgery (on the left), the patient had a fair amount of trefoil (red arrow). The map on the right shows that this has been dramat- ically reduced because CONTOU- RA Vision treated all of the small corneal abnormalities that created the trefoil. Shown in Figure 6 are the pre- and postoperative point spread function (PSF) maps for the eye. The goal is for all of the blue to be in the Figure 3. Ablation profile showing small unique topographical abnormalities that CONTOURA Vision corrected Figure 4. Comparing the preoperative and postoperative exams to see changes made to the cornea Figure 5. Zywave wavefront analysis charts show the patient's ocular higher order aberrations before and after surgery Figure 6. Pre- and postop point spread function maps Source (all): Mark Lobanoff, MD Innovations in cataract and refractive surgery Please refer to pages 7 and 8 for Important Product Information about the Alcon products described in this supplement.

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