title: Power prediction for one-piece and three-piece intraocular lens implantation after cataract surgery in patients with chronic angle-closure glaucoma: a prospective, randomized clinical trial.
abstract: OBJECTIVE
  To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery in chronic angle-closure glaucoma (CACG) patients with different IOLs' implantation.
  
  
  METHODS
  This prospective randomized clinical trial included 45 eyes with CACG and 48 eyes with normal controls undergoing cataract surgery. In the CACG group, 23 eyes (51%) had three-piece IOL implantation and 22 eyes (49%) had one-piece IOL implantation. In the normal control group, 25 eyes (52%) had three-piece IOL implantation and 23 eyes (48%) had one-piece IOL implantation. Using the SRK/T formula, the mean difference between the predicted and actual postoperative spherical equivalent [mean absolute error (MAE)] was obtained and converted to natural logarithm (ln) for statistical analysis. The power of the implanted IOL was calculated to predict postoperative SE using three formulas: SRK II, Holladay II and Hoffer Q by post hoc analysis in each group. The predictive accuracy of each formula was analysed by comparing the lnMAE.
  
  
  RESULTS
  In the one-piece IOL group, there was no difference in lnMAE between the CACG and normal control group (p = 0.314). In the three-piece IOL group, the lnMAE of the CACG group was larger than that of the normal control group (p < 0.001). The lnMAEs calculated by the SRK/T formula were more accurate than the Holladay II (p = 0.045) and Hoffer Q (p = 0.042) formula in the CACG one-piece IOL group.
  
  
  CONCLUSIONS
  Implantation of one-piece IOLs provides similar power prediction accuracy comparable to normal cataract patients; this result may be explained by the IOL haptic configuration or design.
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, Korea Seran Eye Center, Seoul, Korea.
authors.forename: Soolienah
authors.initials: S
authors.lastname: Rhiu
authors.forename: Eun Suk
authors.initials: ES
authors.lastname: Lee
authors.forename: Tae-im
authors.initials: TI
authors.lastname: Kim
authors.forename: Hye Sun
authors.initials: HS
authors.lastname: Lee
authors.forename: Chan Yun
authors.initials: CY
authors.lastname: Kim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001699:Biometry; D002386:Cataract / Q000150:complications*; D002908:Chronic Disease; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000150:complications*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D055095:Optics and Photonics; D018918:Phacoemulsification; D011446:Prospective Studies; D011474:Prosthesis Design; D012029:Refraction, Ocular / Q000502:physiology; D015203:Reproducibility of Results; D014065:Tonometry, Ocular; D014792:Visual Acuity / Q000502:physiology