title: Accuracy of the refractive prediction determined by multiple currently available intraocular lens power calculation formulas in small eyes.
abstract: OBJECTIVE
  To observe the refractive outcomes of cataract surgery in small adult eyes, and to investigate the accuracy of different intraocular lens (IOL) power prediction formulas.
  
  
  METHODS
  Retrospective interventional case series.
  
  
  METHODS
  We included consecutive small eyes undergoing uneventful phacoemulsification cataract surgery with a single highly powerful IOL (Acrysof SA60AT) implanted in the capsular bag (range of powers +35.0 to +40.0 diopters [D]), at the Cataract Centre for Moorfields Eye Hospital. Exclusion criteria were combined or previous intraocular surgical procedures, and any type of intraoperative complications. Main outcome measures were mean prediction errors with Hoffer Q, Holladay 1, Holladay 2, Haigis, SRK-T, and SRK-II IOL power prediction formulas and proportions of eyes achieving absolute errors within the dioptric ranges of 0.5, 1.0, and 2.0 D of target and emmetropia, respectively. The ANOVA test was used to compare the refractive results among various formulas.
  
  
  RESULTS
  Twenty-eight eyes were studied; the mean numerical error was 0.22 ± 1.22 D and the mean absolute error was 0.95 ± 0.78 D with the adopted Hoffer Q formula; 39%, 61%, and 89% of the eyes had a final refraction within 0.5 D, 1.0 D, and 2.0 D of target, respectively. None of the latest-generation formulas significantly outperformed the others (P = .245).
  
  
  CONCLUSIONS
  The Hoffer Q formula led to good or fair refractive outcomes in less than two thirds of the cases. With Holladay 1 and 2 and Haigis formulas, outcomes would have not been significantly different. The SRK formulas yielded less accurate predictions. Possible reasons are discussed.
authors.affiliation: Moorfields Eye Hospital, London, United Kingdom. Electronic address: gianlucacarifi@gmail.com.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Carifi
authors.affiliation: Moorfields Eye Hospital, London, United Kingdom.
authors.forename: Francesco
authors.initials: F
authors.lastname: Aiello
authors.affiliation: Moorfields Eye Hospital, London, United Kingdom.
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Zygoura
authors.affiliation: Moorfields Eye Hospital, London, United Kingdom.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Kopsachilis
authors.affiliation: Moorfields Eye Hospital, London, United Kingdom.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Maurino
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001699:Biometry; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D055095:Optics and Photonics; D018918:Phacoemulsification; D019591:Pseudophakia / Q000503:physiopathology*; D012029:Refraction, Ocular / Q000502:physiology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014792:Visual Acuity / Q000502:physiology*