title: Intraocular lens power calculation for lens exchange.
abstract: OBJECTIVE
  To examine patients who had intraocular lens (IOL) exchange for large postoperative refractive errors and determine the factors that contributed to the error in IOL power calculation.
  
  
  METHODS
  Thirteen affiliated hospitals in Japan.
  
  
  METHODS
  This study comprised 34 cases that required IOL exchange because of large refractive errors after primary lens implantation. Patients with intraoperative complications were excluded from the study. The potential contribution of axial length, corneal refractive power, IOL manufacturer, and IOL fixation to errors in the predicted power was examined retrospectively. Axial length was calculated by the SRK/T and Holladay formulas using refraction after primary IOL implantation.
  
  
  RESULTS
  There was no statistical difference between the corneal refractive power before and after cataract surgery. The axial lengths calculated using the SRK/T and Holladay formulas were longer than the ultrasonic axial lengths in 24 and 23 cases, respectively. Using IOLs from the same manufacturer for both primary implantation and exchange reduced the error in predicted refraction.
  
  
  CONCLUSIONS
  Axial length and IOL manufacturer were important factors in predicting refraction power in eyes requiring IOL exchange.
authors: Department of Ophthalmology Hamamatsu Medical Center, (Kora), Shizuoka, Japan.
authors: Y
authors: Y
authors: Kora
authors: K
authors: K
authors: Shimizu
authors: M
authors: M
authors: Yoshida
authors: M
authors: M
authors: Inatomi
authors: T
authors: T
authors: Ozawa
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular / Q000009:adverse effects; D007910:Lenses, Intraocular; D008297:Male; D055095:Optics and Photonics; D011183:Postoperative Complications / Q000601:surgery; D012029:Refraction, Ocular; D012030:Refractive Errors / Q000209:etiology; D054140:Refractive Surgical Procedures; D012086:Reoperation; D012307:Risk Factors