title: Surface calcification of silicone plate intraocular lenses in patients with asteroid hyalosis.
abstract: OBJECTIVE
  To report three cases in which a silicone-plate lens was explanted because of whitish deposits on the posterior optic surface.
  
  
  METHODS
  Observational case series with clinicopathological correlation.
  
  
  METHODS
  In the three instances, the deposits were observed at least 2 years after uneventful cataract surgery. All of the patients had unilateral mild asteroid hyalosis in the concerned eye. After explantation of the lenses, gross and light microscopic analyses were performed. The posterior optic surfaces of the lenses also underwent scanning electron microscopy coupled with energy dispersive x-ray spectroscopy for analysis of the elemental composition of the deposits.
  
  
  RESULTS
  Gross and light microscopic analyses revealed well-demarcated areas of whitish deposits on the posterior optic surface of the lenses, as well as multiple pits caused by Neodymium:yttrium aluminum garnet laser treatments. The deposits formed an amorphous layer with a "crustlike" appearance, which was confirmed by scanning electron microscopy. X-ray spectroscopy analyses demonstrated the composition of the deposits to be similar to hydroxyapatite.
  
  
  CONCLUSIONS
  The material opacifying the lenses was probably derived from the asteroid bodies or from a similar process that results in this vitreous condition. We were unaware of this association between asteroid hyalosis and late postoperative dystrophic calcification of silicone lenses.
authors.affiliation: Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah 84132, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Foot
authors.forename: Liliana
authors.initials: L
authors.lastname: Werner
authors.forename: James P
authors.initials: JP
authors.lastname: Gills
authors.forename: David W
authors.initials: DW
authors.lastname: Shoemaker
authors.forename: Paul S
authors.initials: PS
authors.lastname: Phillips
authors.forename: Nick
authors.initials: N
authors.lastname: Mamalis
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Olson
authors.forename: David J
authors.initials: DJ
authors.lastname: Apple
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001672:Biocompatible Materials; D002114:Calcinosis / Q000209:etiology* / Q000473:pathology; D020878:Device Removal; D017886:Durapatite / Q000032:analysis; D004577:Electron Probe Microanalysis; D005128:Eye Diseases / Q000150:complications*; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular / Q000009:adverse effects*; D008297:Male; D008855:Microscopy, Electron, Scanning; D018918:Phacoemulsification; D011475:Prosthesis Failure; D012826:Silicone Elastomers / Q000009:adverse effects* / Q000737:chemistry; D014822:Vitreous Body / Q000473:pathology*
chemical_list: D001672:Biocompatible Materials; D012826:Silicone Elastomers; D017886:Durapatite