title: Posterior chamber phakic intraocular lens for myopia of -8 to -19 diopters.
abstract: OBJECTIVE
  To examine the efficacy, predictability, stability, and safety of posterior chamber phakic intraocular lens (IOL) implantation in patients with extreme myopia.
  
  
  METHODS
  We analyzed the results of 124 eyes that received a posterior chamber hydrogel collagen plate phakic IOL (Staar Collamer Implantable Contact Lens, ICL) for the correction of their myopia. The target postoperative spherical equivalent refraction was emmetropia. Mean follow-up was 11 months (range 1 to 36 mo).
  
  
  RESULTS
  The mean preoperative spherical equivalent refraction was -13.38 +/- 2.23 D (range, -8.50 to -18.63 D). Mean postoperative spherical equivalent refraction at last examination was -0.78 +/- 0.87 D (range, +1.63 to -3.50 D), with 69% (86 eyes) within +/-1.00 D and 44% (55 eyes) within +/-0.50 D of emmetropia. The refraction remained stable with a statistically insignificant change (p > 0.05 at each interval) during follow-up. A gain of two or more lines of spectacle-corrected visual acuity was seen in 36% (45 eyes) at last examination. One eye (0.8%) lost two or more lines of spectacle-corrected visual acuity from a retinal detachment.
  
  
  CONCLUSIONS
  Posterior chamber phakic IOL implantation with the Staar Collamer plate lens is an effective and safe method for reducing or correcting myopia between -8 and -19 D. Gains in spectacle-corrected visual acuity were common, and results suggested good refractive stability. Improvements in phakic IOL power calculation formulas are needed to improve the predictability of refractive outcome.
authors.affiliation: Instituto Zaldivar, Mendoza, Argentina.
authors.forename: R
authors.initials: R
authors.lastname: Zaldivar
authors.forename: J M
authors.initials: JM
authors.lastname: Davidorf
authors.forename: S
authors.initials: S
authors.lastname: Oscherow
mesh_terms: D000328:Adult; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications; D019654:Lens Implantation, Intraocular / Q000379:methods*; D007908:Lens, Crystalline; D007910:Lenses, Intraocular; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D011183:Postoperative Complications; D012029:Refraction, Ocular; D012449:Safety; D016896:Treatment Outcome; D014792:Visual Acuity