title: Bilateral cataract after phakic posterior chamber top hat-style silicone intraocular lens.
abstract: BACKGROUND
  New strategies have been developed for surgical treatment of high myopia. Recently, implantation of minus power posterior chamber intraocular lenses (IOL) into phakic eyes has been introduced.
  
  
  METHODS
  We report a 37 year-old female patient who developed bilateral anterior subcapsular cataract 7 years after minus-power, top hat-style silicone posterior chamber IOL implantation in Russia. The corrected visual acuity was right eye 20/200 and left eye 20/63. Because of the high myopia and the posterior chamber IOL in her phakic eyes, biometry for IOL calculation gave contradictory results. Both posterior chamber IOLs were found to be adherent to the crystalline lenses. After posterior chamber IOL explantation and phacoemulsification, intraoperative retinoscopy was performed. With this aphakic refraction, the IOL power was calculated and implanted. The explanted posterior chamber IOLs were examined by scanning electron microscopy.
  
  
  RESULTS
  After bilateral operation the corrected visual acuity increased to right eye 20/32 and left eye 20/40, respectively. On scanning electron microscopy, a membranous structure of unknown origin was noted on the entire surface of the explanted posterior chamber IOLS.
  
  
  CONCLUSIONS
  There is a potential risk of cataract formation after implantation of this top hat-style silicone posterior chamber IOL. If cataract extraction in this specific situation is needed, a different approach for calculating the aphakic IOL power is necessary, such as intraoperative retinoscopy.
authors.affiliation: Department of Ophthalmology, Christian-Albrechts-University, Kiel, Germany. bwiechens@ophthalmol.uni-kiel.de
authors.forename: B
authors.initials: B
authors.lastname: Wiechens
authors.forename: M
authors.initials: M
authors.lastname: Winter
authors.forename: W
authors.initials: W
authors.lastname: Haigis
authors.forename: W
authors.initials: W
authors.lastname: Happe
authors.forename: S
authors.initials: S
authors.lastname: Behrendt
authors.forename: R
authors.initials: R
authors.lastname: Rochels
mesh_terms: D000328:Adult; D001485:Basement Membrane / Q000648:ultrastructure; D002386:Cataract / Q000209:etiology*; D005260:Female; D006801:Humans; D007908:Lens, Crystalline; D007910:Lenses, Intraocular / Q000009:adverse effects*; D008279:Magnetic Resonance Imaging; D008855:Microscopy, Electron, Scanning; D009216:Myopia / Q000601:surgery; D018918:Phacoemulsification; D012826:Silicone Elastomers / Q000009:adverse effects*; D014792:Visual Acuity
chemical_list: D012826:Silicone Elastomers