title: Accuracy of the Holladay 2 intraocular lens formula for pediatric eyes in the absence of preoperative refraction.
abstract: OBJECTIVE
  To evaluate the prediction error in pediatric eyes using the Holladay 2 formula in the absence of preoperative refraction and to compare it with the prediction error using the Holladay 1, Hoffer Q, and SRK/T formulas.
  
  
  METHODS
  Storm Eye Institute, Charleston, South Carolina, USA.
  
  
  METHODS
  Evaluation of diagnostic test or technology.
  
  
  METHODS
  Eyes having pediatric cataract surgery with intraocular lens (IOL) implantation were analyzed. One eye of bilateral cases was randomly selected for inclusion. Prediction error was calculated using the predicted postoperative refraction minus the actual postoperative refraction.
  
  
  RESULTS
  Forty-five eyes were included. The median age at surgery was 3.56 years and the median follow-up, 28 days. Using the Holladay 2, Holladay 1, Hoffer Q, and SRK/T formulas, the mean prediction error was 0.02 diopter (D) ± 0.91 (SD), -0.21 ± 0.90 D, 0.07 ± 1.01 D, and -0.47 ± 0.98 D, respectively. The mean absolute prediction error was 0.68 ± 0.61 D, 0.71 ± 0.58 D, 0.72 ± 0.71 D, and 0.84 ± 0.69 D, respectively. The Holladay 2 formula had the least prediction error for shorter eyes (<22.0 mm). The mean difference between the actual versus the predicted refraction was -0.05 D using Holladay 2 (P=.71), -0.02 D using Holladay 1 (P= .89), -0.12 D using Hoffer Q (P=.44), and 0.04 D using SRK/T (P=.78).
  
  
  CONCLUSIONS
  The Holladay 2 formula had the least prediction error and absolute prediction error even in the absence of preoperative refraction.
authors.affiliation: Miles Center for Pediatric Ophthalmology, Storm Eye Institute, Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, USA. trivedi@musc.edu
authors.forename: Rupal H
authors.initials: RH
authors.lastname: Trivedi
authors.forename: M Edward
authors.initials: ME
authors.lastname: Wilson
authors.forename: Wade
authors.initials: W
authors.lastname: Reardon
mesh_terms: D001699:Biometry / Q000379:methods*; D002387:Cataract Extraction; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D033401:Microscopy, Acoustic; D055095:Optics and Photonics; D012029:Refraction, Ocular / Q000502:physiology*; D015203:Reproducibility of Results; D042262:Retinoscopy; D014792:Visual Acuity / Q000502:physiology