title: Silicone intraocular lens surface calcification in a patient with asteroid hyalosis.
abstract: OBJECTIVE
  To confirm a substance presence on the posterior intraocular lens (IOL) surface in a patient with asteroid hyalosis.
  
  
  METHODS
  An 80-year-old man had IOLs for approximately 12 years. Opacities and neodymium-doped yttrium aluminum garnet pits were observed on the posterior surface of the right IOL. Asteroid hyalosis and an epiretinal membrane were observed OD. An IOL exchange was performed on 24 March 2008, and the explanted IOL was analyzed using a light microscope and a transmission electron microscope with a scanning electron micrograph and an energy-dispersive X-ray spectrometer for elemental analysis. To confirm asteroid hyalosis, asteroid bodies were examined with the ionic liquid (EtMeIm+ BF4-) method using a field emission scanning electron microscope (FE-SEM) with digital beam control RGB mapping.
  
  
  RESULTS
  X-ray spectrometry of the deposits revealed high calcium and phosphorus peaks. Spectrometry revealed that the posterior IOL surface opacity was due to a calcium-phosphorus compound. Examination of the asteroid bodies using FE-SEM with digital beam control RGB mapping confirmed calcium and phosphorus as the main components.
  
  
  CONCLUSIONS
  Calcium hydrogen phosphate dihydrate deposits were probably responsible for the posterior IOL surface opacity. Furthermore, analysis of the asteroid bodies demonstrated that calcium and phosphorus were its main components.
authors.affiliation: Department of Ophthalmology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa-ken 252-0375, Japan. screwup@me.com
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Matsumura
authors.forename: Masahiko
authors.initials: M
authors.lastname: Takano
authors.forename: Kimiya
authors.initials: K
authors.lastname: Shimizu
authors.forename: Noriko
authors.initials: N
authors.lastname: Nemoto
mesh_terms: D000369:Aged, 80 and over; D002114:Calcinosis / Q000150:complications* / Q000175:diagnosis; D002118:Calcium / Q000032:analysis; D002130:Calcium Phosphates / Q000032:analysis; D020878:Device Removal; D004577:Electron Probe Microanalysis; D005128:Eye Diseases / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D008855:Microscopy, Electron, Scanning; D010758:Phosphorus / Q000032:analysis; D011475:Prosthesis Failure; D012086:Reoperation; D012826:Silicone Elastomers; D014822:Vitreous Body / Q000473:pathology*
chemical_list: D002130:Calcium Phosphates; D012826:Silicone Elastomers; D010758:Phosphorus; C485829:calcium phosphate, dibasic, anhydrous; D002118:Calcium