title: A new central-peripheral corneal curvature method for intraocular lens power calculation after excimer laser refractive surgery.
abstract: OBJECTIVE
  To propose the central-peripheral (C-P) method, which requires no data history to calculate intraocular lens (IOL) powers for eyes that underwent laser in situ keratomileusis (LASIK), and compare the accuracy of the C-P method with other IOL formulas for eyes after LASIK.
  
  
  METHODS
  Sixteen patients with cataract (25 eyes) who underwent myopic LASIK were analysed retrospectively. The C-P method is a modified double-K method using the SRK/T formula, in which the estimated pre-LASIK keratometric power calculated from the post-LASIK peripheral anterior sagittal power (also called the axial power) is used for the Kpre in the double-K method using the SRK/T formula, and the post-LASIK anterior sagittal power is used for the Kpost. We compared the accuracy of the C-P method with other popular IOL calculation formulas for use in eyes after LASIK.
  
  
  RESULTS
  The median values of the arithmetic and absolute prediction errors with the C-P method were 0.11 diopter (D) (range, -1.67 to 1.97 D) and 0.55 D (range, 0.02-1.97 D), respectively. The prediction error using the C-P method was within ±0.5 D in 48% of eyes, within -1.0 to +0.5 D in 60% of eyes, and within ±1.0 D in 68% of eyes. The C-P method resulted in a significantly higher percentage of eyes within ±0.5 D than the BESSt formula, Shammas-PL formula, true net power method, double-K method using 43.5 D for Kpre, and Feiz-Mannis method.
  
  
  CONCLUSIONS
  The C-P method may be a good option for calculating IOL powers in eyes undergoing cataract surgery after LASIK when the preoperative LASIK data are unavailable.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Megumi
authors.initials: M
authors.lastname: Saiki
authors.forename: Kazuno
authors.initials: K
authors.lastname: Negishi
authors.forename: Naoko
authors.initials: N
authors.lastname: Kato
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Arai
authors.forename: Ikuko
authors.initials: I
authors.lastname: Toda
authors.forename: Hidemasa
authors.initials: H
authors.lastname: Torii
authors.forename: Murat
authors.initials: M
authors.lastname: Dogru
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
mesh_terms: D000328:Adult; D000368:Aged; D058452:Axial Length, Eye / Q000473:pathology; D001699:Biometry / Q000379:methods*; D003315:Cornea / Q000473:pathology*; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D054018:Lasers, Excimer / Q000627:therapeutic use*; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery; D055095:Optics and Photonics; D018918:Phacoemulsification; D012029:Refraction, Ocular / Q000502:physiology; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult