title: Clinical features of 46 eyes with calcified hydrogel intraocular lenses.
abstract: OBJECTIVE
  To clarify the clinical features of delayed calcification of hydrogel intraocular lenses (IOLs) based on observation of a large case series.
  
  
  METHODS
  Ophthalmology department of 2 university teaching hospitals, Hong Kong, China.
  
  
  METHODS
  The first 44 patients with a known diagnosis of calcified IOL were recruited. Medical and ophthalmic histories were obtained. Surgical details, surgical complications, and visual acuity before and after IOL implantation were also retrieved. Patients then had a visual acuity test, a slitlamp examination of the features of the IOL calcification, and a fundus examination for clarity of view.
  
  
  RESULTS
  Forty-six eyes of 44 patients had IOL calcification. All had a Hydroview IOL. The onset was from 4 to 26 months after surgery. Ninety-three percent of eyes had generalized IOL calcification, and 96% had forceps marks on the IOL. Mean visual acuity deteriorated from 0.4 at 3 months to 0.13 at 19 months. Visual loss was more severe in patients with diabetes mellitus or ischemic heart disease and in those in which the IOL calcified earlier after implantation.
  
  
  CONCLUSIONS
  All cases of IOL calcification were delayed in onset. The presence of forceps marks may provide a clue to the pathogenesis. Bilateral but asymmetric involvement in 2 patients suggests that the IOL was involved in the pathogenesis. Affected patients lost an average of 2.8 Snellen lines of visual acuity. Some eyes progressed more rapidly; however, the modulating factors remain unknown.
authors.affiliation: Department of Ophthalmology, Queen Mary Hospital, Hong Kong, China. yualexis@netscape.net
authors.forename: A K
authors.initials: AK
authors.lastname: Yu
authors.forename: K Y
authors.initials: KY
authors.lastname: Kwan
authors.forename: D H
authors.initials: DH
authors.lastname: Chan
authors.forename: D Y
authors.initials: DY
authors.lastname: Fong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001672:Biocompatible Materials; D002114:Calcinosis / Q000145:classification / Q000175:diagnosis*; D005260:Female; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification; D013997:Time Factors; D014786:Vision Disorders / Q000145:classification / Q000175:diagnosis; D014792:Visual Acuity
chemical_list: D001672:Biocompatible Materials; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate