title: Opacification of hydrophilic acrylic intraocular lenses: a clinical and ultrastructural analysis of three explanted lenses.
abstract: BACKGROUND
  The purpose of our study was to report the clinical and ultrastructural results of the late opacification of three Hydroview intraocular lenses (IOLs) explanted from three patients with late postoperative visual acuity drop.
  
  
  METHODS
  Three different patients without any systemic or ocular associated pathology presented with decreased visual acuity 12 to 24 months after uneventful phacoemulsification and Hydroview IOL implantation. The lenses were explanted and examined by photon and transmission electron microscopy (TEM), as well as through laboratory chemical analysis using bleaching with H 2 O 2, SDS-electrophoresis and silver staining for protein detection. They were cut in small pieces, fixed with osmium tetroxide 1.5 %, dehydrated through ascending grades of ethanol, and embedded in EPON 812. Ultrathin sections were stained with aqueous solutions of uranyl acetate and lead citrate, and they were examined with JEOL 2000 CX TEM. One normal IOL was also prepared in the same way and served as control.
  
  
  RESULTS
  
  
  
  METHODS
  It was transparent and no material on the surface of semithin and thin sections was detected. Cases 1 and 2: A total gray-whitish opacification of these lenses occurred. An amorphous loose material was present on semithin sections in alternation with normal areas. Evaluation with TEM revealed a pattern of network distribution within the lenses material. The latter was continuous and lightly granulated at the periphery, yet irregularly arranged in the center, more intensely stained, leaving areas of normal appearance. After bleaching, no changes in opacification were seen macroscopically. SDS-electrophoresis and silver staining did not detect proteins. Case 3: This lens had a small opacification close to the periphery.
  
  
  CONCLUSIONS
  Late opacification of hydrophilic IOLs is not an uncommon phenomenon after uneventful cataract surgery. Although calcified deposits on the surfaces of such lenses have been reported, this is the first study that describes ultrastructural changes in the IOL material itself.
authors.affiliation: Department of Ophthalmology, General Hospital of Patras Agios Andreas, Patras, Greece. jkatsimpris@yahoo.com
authors.forename: John M
authors.initials: JM
authors.lastname: Katsimpris
authors.forename: Kokona
authors.initials: K
authors.lastname: Koliakou
authors.forename: Ioannis K
authors.initials: IK
authors.lastname: Petropoulos
authors.forename: Anastasios G
authors.initials: AG
authors.lastname: Konstas
mesh_terms: D000368:Aged; D002118:Calcium / Q000032:analysis; D020878:Device Removal; D004591:Electrophoresis, Polyacrylamide Gel; D019544:Equipment Failure Analysis; D005136:Eye Proteins / Q000032:analysis; D005260:Female; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D008854:Microscopy, Electron; D011183:Postoperative Complications / Q000473:pathology*; D011474:Prosthesis Design
chemical_list: D005136:Eye Proteins; D002118:Calcium