title: Comparison of surgically-induced astigmatism after combined phacoemulsification and 23-gauge vitrectomy: 2.2-mm vs. 2.75-mm cataract surgery.
abstract: OBJECTIVE
  The 2.2-mm microincision cataract surgery and small-gauge vitrectomy system is known to result in less surgically-induced astigmatism (SIA) in comparison to conventional surgical methods. We compared the amounts of SIA after combined phacoemulsification and 23-gauge transconjunctival sutureless vitrectomy (23G-TSV) using the 2.2-mm microincision and 2.75-mm standard incision methods.
  
  
  METHODS
  We studied 59 patients (61 eyes) who underwent combined phacoemulsification and 23G-TSV from November 2008 to September 2012. Twenty-eight patients (28 eyes) underwent 2.2-mm microincision coaxial phacoemulsification, and 31 patients (33 eyes) underwent 2.75-mm standard incision phacoemulsification. SIA was evaluated using Naeser's polar method with the simulated keratometric values obtained from corneal topography. Preoperative and 1-week and 1-month postoperative KP (Naeser's polar value along the specific axis) and ΔKP values were compared between the 2.2-mm microincision and 2.75-mm standard incision groups.
  
  
  RESULTS
  One week after surgery, both groups exhibited similar amounts of SIA (-ΔKP[120], 0.40 ± 0.41 vs. 0.51 ± 0.56 diopters [D]; p = 0.390). One month after surgery, however, the amount of SIA was significantly smaller in the 2.2-mm microincision group as compared to the 2.75-mm standard incision group (-ΔKP[120], 0.31 ± 0.54 vs. 0.56 ± 0.42 D; p = 0.045).
  
  
  CONCLUSIONS
  In combined phacoemulsification with 23G-TSV, 2.2-mm microincision coaxial phacoemulsification induces less SIA than does 2.75-mm standard coaxial phacoemulsification.
authors.affiliation: Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Yong-Kyu
authors.initials: YK
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Yong Woo
authors.initials: YW
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Se Joon
authors.initials: SJ
authors.lastname: Woo
authors.affiliation: Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Kyu Hyung
authors.initials: KH
authors.lastname: Park
mesh_terms: D000368:Aged; D001251:Astigmatism / Q000175:diagnosis / Q000209:etiology*; D002386:Cataract; D003315:Cornea / Q000601:surgery; D019781:Corneal Topography / Q000379:methods; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular / Q000009:adverse effects* / Q000379:methods; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification / Q000009:adverse effects* / Q000379:methods; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology; D012590:Sclera / Q000601:surgery; D014821:Vitrectomy / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods
keywords: Microincision; Phacoemulsification; Surgically-induced astigmatism; Transconjunctival sutureless vitrectomy