title: Comparison of surgically induced astigmatism between one-handed and two-handed cataract surgery techniques.
abstract: BACKGROUND
  The purpose of this study was to compare surgically induced astigmatism (SIA) between one-handed and two-handed cataract surgery techniques.
  
  
  METHODS
  Eighty-eight eyes of 44 patients with no ocular disease other than cataract, who underwent cataract surgery by a single surgeon, were selected for this study. Cataract surgery was performed by coaxial phacoemulsification and intraocular lens implantation via a 2.4 mm transconjunctival single-plane sclerocorneal incision at the 12 o'clock position. In each patient, one eye was subjected to coaxial phacoemulsification using a one-handed technique while the fellow eye was subjected to coaxial phacoemulsification using a two-handed technique. For the two-handed technique, a corneal side port was created at the 2 o'clock position. The appropriate incision meridian was identified by a preoperative axis mark. SIA was calculated using the Alpins method.
  
  
  RESULTS
  Mean SIA was 0.40 ± 0.28 diopters (D) in the one-handed technique group and 0.39 ± 0.25 D in the two-handed technique group. No statistically significant difference was found in the mean SIA score. The mean torque value was -0.05 ± 0.26 D in the one-handed technique group and 0.11 ± 0.37 D in the two-handed technique group. Mean torque was significantly lower (P<0.05) in the one-handed technique group than in the two-handed technique group.
  
  
  CONCLUSIONS
  The results indicate that the corneal side port in two-handed cataract surgery has a rotating effect on the axis of astigmatism.
authors.affiliation: Department of Ophthalmology, Spporo Tokushukai Hospital, Sapporo, Asahikawa, Japan.
authors.forename: Asushi
authors.initials: A
authors.lastname: Kawahara
authors.forename: Daijiro
authors.initials: D
authors.lastname: Kurosaka
authors.forename: Aktoshi
authors.initials: A
authors.lastname: Yoshida
keywords: cataract surgery; corneal side port; surgically induced astigmatism