title: Surface calcification of a 3-piece silicone intraocular lens in a patient with asteroid hyalosis: a clinicopathologic case report.
abstract: OBJECTIVE
  To illustrate the laboratory findings in a patient with bilateral asteroid hyalosis who presented with calcified deposits on a 3-piece silicone intraocular lens (IOL).
  
  
  METHODS
  Observational case report.
  
  
  METHODS
  A 76-year-old diabetic woman underwent uneventful cataract surgery in 1994 with implantation of a silicone-optic polypropylene-haptic IOL in the left eye. A neodymium:yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy was performed 2 years after cataract surgery, but persistent whitish deposits were observed on the posterior optic surface of the lens. Over the next 3 years, the opacification increased in the region corresponding to the capsulotomy. The IOL was explanted/exchanged. The right eye had cataract surgery in 1995. The acrylic lens implanted in this eye developed no opacities after 6 years.
  
  
  METHODS
  Gross, microscopic, and surface analyses of the explanted IOL.
  
  
  RESULTS
  Gross and light microscopic analyses revealed the presence of confluent crustlike deposits on the central area of the posterior optic surface, as well as Nd:YAG pits. Individual spherules exhibiting a Maltese-cross pattern under polarizing light were also observed. Energy dispersive x-ray spectroscopic analyses demonstrated the composition of the confluent deposits to be similar to hydroxyapatite.
  
  
  CONCLUSIONS
  An association between asteroid hyalosis and dystrophic calcification of IOLs has been reported only with silicone plate haptic designs. The material opacifying the 3-piece silicone lens probably was derived from the asteroid bodies or from the process that results in this vitreous condition. Clinical evaluation of other pseudophakic patients with asteroid hyalosis will confirm if this phenomenon is restricted to silicone IOLs.
authors.affiliation: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah 84132, USA. liliana.werner@hsc.utah.edu
authors.forename: Liliana
authors.initials: L
authors.lastname: Werner
authors.forename: Carol R
authors.initials: CR
authors.lastname: Kollarits
authors.forename: Nick
authors.initials: N
authors.lastname: Mamalis
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Olson
mesh_terms: D000368:Aged; D001672:Biocompatible Materials; D002114:Calcinosis / Q000209:etiology* / Q000473:pathology; D020878:Device Removal; D004577:Electron Probe Microanalysis; D005128:Eye Diseases / Q000150:complications*; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D019904:Polymethyl Methacrylate; D011475:Prosthesis Failure; D012086:Reoperation; D012826:Silicone Elastomers; D014822:Vitreous Body / Q000473:pathology*
chemical_list: D001672:Biocompatible Materials; D012826:Silicone Elastomers; D019904:Polymethyl Methacrylate