title: Intraocular lens prediction accuracy after corneal refractive surgery using K values from 3 devices.
abstract: OBJECTIVE
  To compare results of intraocular lens (IOL) power calculation methods using different keratometry (K) values after myopic refractive surgery.
  
  
  METHODS
  Seoul St. Mary's Hospital, Seoul, South Korea.
  
  
  METHODS
  Evaluation of diagnostic test or technology.
  
  
  METHODS
  The IOL power of patients who had cataract surgery after refractive surgery was calculated using the SRK/T formula with true net power (TNP) and the equivalent K using the Pentacam Scheimpflug system. The simulated K, 2.0 mm zone of total mean power (TMP 2.0 mm) maps, and 4.0 mm zone of total optical power (TOP 4.0 mm) maps were calculated using the Orbscan II scanning-slit topographer and keratometer of the IOLMaster partial coherence interferometer (PCI). The IOL power was also calculated with the Haigis-L method with the corneal radius using the PCI system. The PCI axial length was used with all methods.
  
  
  RESULTS
  The prediction error and absolute prediction error measured with the Haigis-L, TNP, TMP 2.0 mm, and TOP 4.0 mm were significantly lower than the equivalent K, simulated K, and PCI K (P<.05). The percentages of correct refraction predictions within ± 0.50 diopter (D), ± 1.00 D, and ± 2.00 D in the Haigis-L method were the highest (64.5%, 80.6%, and 100%, respectively) of all methods.
  
  
  CONCLUSIONS
  The Haigis-L using corneal radius with the PCI measurement was the most predictable method for IOL calculation after corneal refractive laser surgery in patients without a clinical history. The TMP 2.0 mm in the scanning-slit topographer and the TNP in the Scheimpflug system may also be relatively predictable keratometric values for IOL calculation.
authors.affiliation: From the Department of Ophthalmology and Visual Science, College of Medicine, Catholic University of Korea, Seoul, South Korea.
authors.forename: Eun Chul
authors.initials: EC
authors.lastname: Kim
authors.forename: Kyongjin
authors.initials: K
authors.lastname: Cho
authors.forename: Ho Sik
authors.initials: HS
authors.lastname: Hwang
authors.forename: Kyu Yeon
authors.initials: KY
authors.lastname: Hwang
authors.forename: Man Soo
authors.initials: MS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D003315:Cornea / Q000601:surgery*; D048988:Corneal Surgery, Laser; D019781:Corneal Topography; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D049451:Nomograms; D055095:Optics and Photonics; D018918:Phacoemulsification; D012029:Refraction, Ocular / Q000502:physiology