Chooing the Location of Corneal Inciion Baed on Preexiting Atigmatim in Phacoemulification

Purpoe To invetigate the bet location of clear-cornea inciion in phacoemulification, depending on preexiting corneal atigmatim. Deign Randomized clinical trial and noncomparative interventional cae erie. Method A total of 574 patient in five tage were aigned to the following inciion: uperior or temporal (n = 89), uperior (n = 141), uperior or uperior plu relaxing (n = 102), naal or temporal (n = 156), and inciion baed on applying concluion of preceding and current tudie (n = 86). Viual acuity, refraction, biomicrocopy, keratometry, and videokeratography (Fourier analyi) were performed before and after phacoemulification and intraocular len implantation (3.5-mm inciion). main outcome meaure: Corneal refractive and urface regularity index change between preoperative and 6-month potoperative examination. Viual acuity at 6 month. Reult In patient without corneal atigmatim, corneal change induced were greater in uperior than temporal inciion. After a uperior inciion (preoperative teep axi at 90 degree), a hift of the axi 90 degree away wa le likely with at leat 1.5 diopter of atigmatim. A perpendicular relaxing limbal inciion decreaed corneal change. Naal inciion induced greater corneal change than temporal inciion (preoperative teep axi at 180 degree). A hift of thi axi 90 degree away wa more likely with atigmatim < 0.75 diopter in temporal inciion and < 1.25 diopter in naal inciion. Concluion uperior inciion i recommended with at leat 1.5 diopter of atigmatim and teep axi at 90 degree. Temporal inciion i recommended with atigmatim < 1.5 diopter and teep axi at 90 degree, negligible atigmatim, or atigmatim < 0.75 diopter and teep axi at 180 degree. Naal inciion i recommended with at leat 0.75 diopter of atigmatim and teep axi at 180 degree.