Vector Analysis Reveals That Topography-Guided LASIK Targeting the Manifest Refraction (MR) is Superior to Topography-Modified Refraction (TMR) and Layer Yolked Reduction of Astigmatism (LYRA) [Letter]

Abstract

Avi Wallerstein,1,2,* Mathieu Gauvin1,2,* 1Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC, Canada; 2LASIK MD, Montreal, QC, Canada*These authors contributed equally to this workCorrespondence: Avi Wallerstein 1250 Rene-Levesque Blvd W, MD Level, Montreal, QC, H3B 4W8 Tel [phone] Ext 2273Email [email protected] We read with interest “Primary Topography-Guided LASIK: A Comparative Study Comparing Treating the Manifest versus the Topographic Astigmatism”.1 We commend the authors for performing vector analysis of surgical astigmatic changes using the standardized Alpins Method for their outcomes analysis paper. However, the papers’ conclusion is not supported by the vector analysis findings.Astigmatism vector analysis answers the following clinical questions: 1 – Was the attempted astigmatic treatment undercorrected or overcorrected? 2 – Was the under/overcorrection due to the magnitude or axis of treatment? 3 – Was there a consistent axis error? Vector analysis is therefore essential for a complete evaluation of excimer surgical outcomes and for determining optimal nomogram adjustments to improve future outcomes. Refractive surgery journals have made this type of analysis the standard for reporting.2 View the original paper by Aboalazayem and colleagues

Keywords

• lasik
• topography-guided
• contoura
• astigmatism
• refraction
• predictability