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5 For me, the LenSx Laser is critical in complicated cataracts. With white cataracts, it is a game changer. It used to be anxiety pro- voking to make the capsulotomy. Now, it's a no brainer. Every time I use the LenSx Laser, it's like magic in the OR seeing that you have a free floating capsulotomy, and the rest of the case goes safely and smoothly. Dense cataracts, especial- ly in patients who have endothelial dystrophy or Fuchs' dystrophy, are another instance where the LenSx Laser plays a huge role in softening the nucleus and allowing for less phaco power. The LenSx Laser also allows for a quicker nucleus disas- sembly so that there is less fluid through the eye. That makes a huge difference in the health of the endo- thelium and the speed of recovery after surgery. Since we first purchased the LenSx Laser in 2012, I have been interested in a complete refractive treatment of the eye and managing astigmatism that could interfere with the patient's postop visual outcome. While the advent of toric lenses helped us make great strides to correct astigmatism at the time of cataract surgery, arcuate inci- sions have remained in my tool kit to address residual astigmatism that would impact a complete refractive correction. However, using a blade (manual) to cut an arcuate during cataract surgery can be unpredictable. The availabili- ty of LenSx to create precise and reproducible arcuate incisions has allowed me to confidently manage even low amounts of astigmatism as well as take one less manual step in performing cataract surgery. I think any amount of astigmatism correc- tion is within my reach with laser or toric lenses or a combination. This has caused us to focus on our outcomes and target zero residual astigmatism in our patients. Contact information McCabe: cmccabe13@hotmail.com continued from page 4 CONTOURA Vision provides a unique, truly customized LASIK procedure by Mark Lobanoff, MD C ONTOURA Vision (Alcon, Fort Worth, Texas) is a significant advancement from traditional LASIK and Wavefront Optimized (Alcon) LASIK because it provides a truly cus- tomized procedure based on each patient's cornea. While CONTOURA Vision marks a great leap forward in patient outcomes, Alcon improved the surgeon experience as well by improving the graphic user interface (GUI) usability and the hardware on the new refractive suites it will be manufacturing moving forward. The focus of this article will be on how CONTOURA Vision delivers on enhanced patient outcomes. Figure 1 shows examples of topographies of two different corneas. Prior to the introduction of CONTOURA Vision, excimer laser treatment software assumed that all corneas were perfect and identical, so for traditional myopic treatments, they would put the same circular treatment pattern on all patients with the same correc- tion. This was true for astigmatic treatments as well; all treatments were uniform for the same amount of astigmatism. However, these topographies show subtle differenc- es from one eye to the next. In the anterior topography maps in Figure 1, the corneas have a yellow raised ridge of tissue across the surface that generates minus cylinder astigmatism. Yet corneal shapes are unique, and every cornea is slightly different. Here, the ridges narrow and flare out at different points (blue arrows). These small topographic imperfections create astigmatism that is mildly irregular and asymmetric. In the bottom axial power maps, the yellow shows where the light is being focused more in- tensely and the light green a little less so. The topography is driving a mildly asymmetric astigmatism (red arrows). A pure perfect astigmatism pattern looks like a bowtie. In a perfect cornea, they would be equal in direction, shape, and magnitude. The images are not perfect bowties. There is asymmetry that is created by the slight imperfections in the corneas' astigmatism. Figure 2 shows the ablation profile that a traditional LASIK or a Wavefront Optimized laser would use to treat astigmatism. It ablates in a perfect rectangular shape. There is a standardized amount of tissue removal in the purple zone all the way across the ridge that is gen- erating minus cylinder astigmatism. This ablation profile is assuming that the astigmatism is perfect, lin- ear, and symmetrical. If this perfect rectangular grid pattern is placed on the corneas in Figure 1, most of the ridge will be removed. But some parts of the ridge, where the yellow tapers down, don't need that full correction. The traditional laser pat- tern would be overcorrecting those areas. Areas where the astigmatism flares out and becomes broader and Figure 1. Topographies of two different corneas Figure 2. Thin lens Source: Cathleen McCabe, MD continued on page 6 Figure 2. Ablation profile that a traditional LASIK or Wavefront Optimized laser would use to treat astigmatism Source (all): Mark Lobanoff, MD

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