title: Evaluation of the quality of generic polymethylmethacrylate intraocular lenses marketed in India.
abstract: OBJECTIVE
  To determine the quality of single-piece, allpolymethylmethacrylate (PMMA) Intraocular lenses (IOLs) from eght generic manufacturers marketing their product in India. This assessment of quality was made with respect to compliance with internationa standards for the manufacture of IOLs, specifically those parameters most likely to affect patient postoperat ve visual acuity and the long-term biocompatibility of the implanted lens.
  
  
  METHODS
  Ten IOLs from each of eight manufacturers were purchased randomly from commercial retail outlets in India. Each IOL, in a masked fashion, had its physical dimensions, optical performance and cosmetic appearance assessed, using the methods prescribed in ISO 11979-2 and 11979-3. Validation of manufacturing process controls were determined by statistical process contro techniques. Four IOLs from each manufacturer were also tested for the presence of unpolymerized PMMA using gas chromatography.
  
  
  RESULTS
  Only lenses from two IOL manufacturers complied with the optical and mechanical standards. All other manufacturers' lenses failed one or more of these tests. Intraocular lenses from only two producers met with surface quality and bulk homogeneity standards. All others exhibited defects such as surface contamination and scratches, poor polishing, and chipped or rough positioning holes. Lenses from two producers exhibited high levels of methylmethacrylate monomer (MMA).
  
  
  CONCLUSIONS
  Non-clinical grade PMMA starting material may have been used in the manufacture of IOLs by some producers. Critical manufacturing defects occurred in the IOLs from five of the eight producers tested. Only one manufacturer's IOLs met all specifications, and on statistical analysis demonstrated good manufacturing process contro with respect to the properties tested. With the widespread acceptance of IOL implantation in developing countries, such as India, it is essential that in the rush to make this the norm, the quality of implants used not be overlooked.
authors.affiliation: The Fred Hollows Foundation, Sydney, NSW, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Combe
authors.forename: R
authors.initials: R
authors.lastname: Watkins
authors.forename: G
authors.initials: G
authors.lastname: Brian
mesh_terms: D001672:Biocompatible Materials / Q000592:standards; D006801:Humans; D007194:India; D007910:Lenses, Intraocular / Q000592:standards*; D008420:Manufactured Materials / Q000592:standards*; D019904:Polymethyl Methacrylate; D055656:Prescriptions; D011786:Quality Control; D013810:Therapeutic Equivalency; D014792:Visual Acuity
chemical_list: D001672:Biocompatible Materials; D019904:Polymethyl Methacrylate