Clinical Ophthalmology (Feb 2021)
Clinical Outcomes After Topography-guided Refractive Surgery in Eyes with Myopia and Astigmatism—Comparing Results with New Planning Software to Those Obtained Using the Manifest Refraction [Letter]
Abstract
Manoj Motwani Motwani LASIK Institute, San Diego, CA, 92121, USACorrespondence: Manoj MotwaniMotwani LASIK Institute, 4520 Executive Dr., Suite 230, San Diego, CA, 92121, USATel +1 858 554-0008Email [email protected] In response to the study performed by Brunson et al “Clinical Outcomes After Topography-guided Refractive Surgery in Eyes with Myopia and Astigmatism—Comparing Results with New Planning Software to Those Obtained Using the Manifest Refraction,” there are significant issues with this study and the use of the Phorcides Analytic Engine that must be examined. 1Both manuscripts now published concerning outcomes from the PAE have essentially followed the same script—focus on comparison to manifest refraction, comparing only visual results, no mention of axis variance from either manifest or Contoura measured astigmatism, no mention of controls in picking patients for inclusion in the study, such as a consecutive series to prevent “cherry-picking,” small deviations in between magnitudes of manifest, Contoura measured, and Phorcides astigmatism, no topographic analysis to demonstrate that a more uniform cornea was being created, no analysis of Zernicke higher order aberration polynomials to show that HOAs were reduced and not induced, no data concerning residual astigmatism after treatment (except for a line stating no patient had greater than 0.5 D of residual astigmatism), no subjective patient outcomes, and no scientific explanation as to why Phorcides should be used and not simply the Contoura measured astigmatism, which also analyses the higher order aberrations on the anterior corneal surface, which is the most important refracting element of any optical system. 1,2View the original paper by Brunson and colleagues A Response to Letter has been published for this article.
