title: Prediction accuracy of intraocular lens power calculation methods after laser refractive surgery.
abstract: BACKGROUND
  This study aimed to evaluate the prediction accuracy of postoperative refractions using partial coherence interferometry (IOL-Master) and applanation ultrasound (AL-3000) assisted with corneal topography (TMS-4) in eyes that had undergone myopic laser-assisted in situ keratomileusis (LASIK).
  
  
  METHODS
  Haigis-L formula, Koch-Maloney method using Haigis formula, Shammas clinically derived K-value (simulated keratometric value) correction (Shammas c.d.) using Haigis formula, and Shammas post-LASIK (Shammas-PL) formula were used in eyes with myopic LASIK. Constants were derived from the optimized constants in 133 virgin eyes. Refractive outcomes were determined by streak retinoscopy and subjective manifest refraction. Methods and formulas were evaluated by mean error (ME), standard deviation (SD), range of error, mean absolute error (MAE), median absolute error, 95% confidence interval of MAE, and percentage of eyes within ±0.5 diopter (D), ±1.0 D, and ±1.5 D of prediction.
  
  
  RESULTS
  SDs of the Haigis-L, Koch-Maloney method using the Haigis formula, Shammas c.d. using the Haigis formula, and the Shammas-PL formula using IOL-Master were 0.721, 0.695, 0.695, and 0.698; and those using AL-3000 assisted with TMS-4 were 0.782, 0.741, 0.743, and 0.778, respectively.
  
  
  CONCLUSIONS
  No-history methods that corrected corneal power with measurements using IOL-Master were promising in myopic post-LASIK eyes, but still a gap in prediction accuracy exists between virgin eyes and post-LASIK eyes.
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, Anhui, 230022, China.
authors.forename: Yubo
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Ultrasound, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, Anhui, 230022, China.
authors.forename: Songyu
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, Anhui, 230022, China. ophthalmology123@foxmail.com.
authors.forename: Rongfeng
authors.initials: R
authors.lastname: Liao
mesh_terms: D003315:Cornea / Q000473:pathology* / Q000601:surgery; D019781:Corneal Topography; D005500:Follow-Up Studies; D006801:Humans; D007368:Interferometry / Q000379:methods*; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D007910:Lenses, Intraocular; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D018918:Phacoemulsification; D012029:Refraction, Ocular / Q000502:physiology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014792:Visual Acuity
keywords: Biometry; Cataract surgery; Intraocular lens power calculation; Lasik