Eyeworld

50 | EYEWORLD | SEPTEMBER 2022 R EFRACTIVE by Vance Thompson, MD Refractive Editor Fundamental concepts in refractive surgery T his issue of EyeWorld ex- plores some of the fundamen- tal concepts in refractive surgery that help us choose which patients are good candidates, the technologies best suited for them, and important follow-up guidelines and their implications. With any refractive procedure, whether it is corneal, phakic IOL, or lens replacement, it is important to do a complete eye exam plus the important additional tests that help optimize the visual results for our patients for the rest of their life. Understanding things like the current optical state of the cornea by assessing the tear film optical quality, corneal topography, epithe- lial thickness, and its higher order aberration state are routine in our comprehensive refrac- tive surgery practice. It is very important to do a proper ocular surface health analysis since the most power- ful refractive element of our eye is the air/tear interface. It amazes me how much visual blur and blink to blink variability can happen with dry eye patients, and this needs to be identified and eliminated prior to surgery through quality therapeutic interventions. A reduced tear film that has an abnor- mal tear film breakup time can also throw off our precision tests that are based on tear film quality and make a cornea look abnormal. It is important for people doing the testing to get the patient properly aligned and set up for a corneal topography, epithelial thickness, or a higher order aberration measurement, such as a wave- front capture, have the patient blink to freshen the tear film, and capture the test for analysis. This consistency in time between a tear film freshening blink and image capture helps a practice deliver more consistent recommenda- tions and surgical results for their patients. Thank you to Kathryn Hatch, MD, and Gregory Parkhurst, MD, for teaching us import- ant pearls and reasons for short- and long-term "Refractive surgery follow-up." Thank you to Daniel Chang, MD, and Douglas Koch, MD, for contributing to "Clearing up angle kappa." Finally, thank you to William Trattler, MD, for providing information on "The impact of corne- al aberrations on refractive surgery." He shares his insights on this important analysis that has revolutionized decision making in refractive and cataract surgery. This issue of EyeWorld will help all anterior segment surgeons increase their knowledge so that we can best serve the patients who come to see us. It amazes me how much visual blur and blink to blink variability can happen with dry eye patients, and this needs to be identified and eliminated prior to surgery through quality therapeutic interventions.

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