title: Gender differences in refractive prediction in refractive lens exchange surgery.
abstract: OBJECTIVE
  To compare the refractive outcomes after refractive lens exchange (RLE) surgery with regards to gender and intraocular lens (IOL) power calculation formula.
  
  
  METHODS
  A cohort of consecutive patients operated with bilateral same-day RLE surgery at a private eye clinic (n = 512) was studied. Target refraction was emmetropia in all cases and Haigis formula was used for all IOL power calculations. One month after surgery, subjective refraction was assessed and the absolute refractive prediction error (RPEAbs), as well as the refractive prediction error with correct signs (RPESign), was calculated, as were the refractive outcomes with the SRK/T formula.
  
  
  RESULTS
  For the whole cohort, the Haigis formula rendered a significantly smaller RPEAbs than the SRK/T formula (0.16 ± 0.26 D vs 0.32 ± 0.30 D; p&lt;0.001). No gender difference in RPEAbs was seen. A slight myopic error was seen with the SRK/T formula in women, and a slight hyperopic error in men (-0.06 ± 0.47 D vs + 0.16 ± 0.39 D; p&lt;0.001). No similar gender difference was seen with the Haigis formula (+0.05 ± 0.29 D vs +0.05 ± 0.31 D; p = NS). Axial length, anterior chamber depth, and corneal steepness differed significantly between the sexes.
  
  
  CONCLUSIONS
  The Haigis formula generally performed better in this RLE cohort. The SRK/T formula generates a small myopic error in women and a hyperopic error in men, associated with flatter corneas, longer axial lengths, and deeper anterior chambers in the latter.
authors.affiliation: Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå - Sweden.
authors.forename: Oskar
authors.initials: O
authors.lastname: Lundqvist
authors.forename: Oscar
authors.initials: O
authors.lastname: Westin
authors.forename: Timo
authors.initials: T
authors.lastname: Koskela
authors.forename: Anders
authors.initials: A
authors.lastname: Behndig
mesh_terms: D000328:Adult; D000368:Aged; D000867:Anterior Chamber / Q000033:anatomy & histology; D058452:Axial Length, Eye / Q000033:anatomy & histology; D001699:Biometry; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000175:diagnosis* / Q000503:physiopathology; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000175:diagnosis* / Q000503:physiopathology; D055095:Optics and Photonics; D019591:Pseudophakia / Q000503:physiopathology; D012029:Refraction, Ocular / Q000502:physiology*; D012189:Retrospective Studies; D012737:Sex Factors