title: Calculation of intraocular lens power with the SRK II formula for axial high myopia.
abstract: OBJECTIVE
  The SRK II formula has been widely used for intraocular lens (IOL) power calculations. The predictability of this formula is evaluated in axial myopic patients.
  
  
  METHODS
  Planned extracapsular cataract extraction and posterior chamber IOL implantation (PECCE + IOL) were performed on 98 eyes of 98 patients with axial length > 24.5 mm. Cases had no preoperative complications and postoperative visual acuity was at least 0.5 (Snellen). Corneal refractive power and axial length were measured preoperatively and emmetropic IOL power calculations were made using the SRK II formula. Long-term (mean 4.7 months) visual acuities and refractions were noted postoperatively.
  
  
  RESULTS
  The absolute refractive error was < 1.00 Diopters (D) in 57 eyes (58.2%) and < 2.00 D in 83 eyes (84.7%). The mean absolute error of the SRK II formula in axial myopia was 1.16 D +/- 0.78 SD.
  
  
  CONCLUSIONS
  The SRK II formula is not very accurate in axial myopic patients.
authors.affiliation: Eye Department, Ankara Hospital, Turkey.
authors.forename: I S
authors.initials: IS
authors.lastname: Yalvaç
authors.forename: A
authors.initials: A
authors.lastname: Nurözler
authors.forename: N
authors.initials: N
authors.lastname: Unlü
authors.forename: F
authors.initials: F
authors.lastname: Cetinkaya
authors.forename: R
authors.initials: R
authors.lastname: Kasim
authors.forename: S
authors.initials: S
authors.lastname: Duman
mesh_terms: D001699:Biometry; D002387:Cataract Extraction; D005123:Eye / Q000033:anatomy & histology; D006801:Humans; D007910:Lenses, Intraocular; D008433:Mathematics; D009216:Myopia / Q000628:therapy*; D055095:Optics and Photonics; D014792:Visual Acuity