title: Opposite clear corneal incisions on the steep meridian in phacoemulsification: early effects on the cornea.
abstract: OBJECTIVE
  To evaluate the effect of on-axis opposite clear corneal incisions (OCCIs) in phacoemulsification on reducing preoperative corneal astigmatism and to predict the astigmatic outcome of the incisions.
  
  
  METHODS
  Royal Eye Infirmary, Dorset County Hospital, and Winterbourne Hospital, Dorchester, Dorset, and the Department of Ophthalmology, East Somerset Hospital, Yeovil, Somerset, United Kingdom.
  
  
  METHODS
  This prospective study included all patients (n = 103) who had on-axis OCCIs as a part of routine phacoemulsification with foldable intraocular lens (IOL) implantation performed by 1 surgeon during 2000. Keratometry was done 6 to 8 weeks postoperatively. The differences in the preoperative and postoperative corneal astigmatism and corneal spherical equivalent (SE) were recorded. Surgically induced astigmatism (SIA) was calculated using vector analysis.
  
  
  RESULTS
  The mean reduction in corneal astigmatism was 0.50 diopter (D) (P<.001). The mean SIA was 1.57 D (95% confidence interval [CI], 1.42 to 1.71). There was a weak association between the SIA and the patient's age and axis of preoperative astigmatism. The mean change in SE was +0.02 D (95% CI, -0.08 to +0.12).
  
  
  CONCLUSIONS
  Results indicate that on-axis OCCIs are a reliable and practical way of reducing preexisting corneal astigmatism. The change in SE was negligible and thus can be ignored during biometry.
authors.affiliation: Royal Eye Infirmary, Dorset County Hospital, Dorchester, Dorset, United Kingdom. athanassius@btinternet.com
authors.forename: Athanassius
authors.initials: A
authors.lastname: Tadros
authors.forename: Maged
authors.initials: M
authors.lastname: Habib
authors.forename: Deepak
authors.initials: D
authors.lastname: Tejwani
authors.forename: Hirut
authors.initials: H
authors.lastname: Von Lany
authors.forename: Peter
authors.initials: P
authors.lastname: Thomas
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000503:physiopathology / Q000517:prevention & control*; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control; D019654:Lens Implantation, Intraocular / Q000379:methods*; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D018918:Phacoemulsification / Q000379:methods*; D011446:Prospective Studies