title: Effect of folding on the multifocal silicone intraocular lens: scanning electron microscopic study.
abstract: OBJECTIVE
  To evaluate whether the surface of the refractive zonal multifocal silicone intraocular lens (IOL) is altered by different folding and implantation instruments and is more sensitive to manipulation during folding than the surface of a monofocal IOL.
  
  
  METHODS
  Department of Ophthalmology, University Hospital, Kiel, Germany.
  
  
  METHODS
  Evaluated were the refractive multifocal silicone IOL (SA-40N, Array) and an otherwise identical monofocal IOL (SI-40NB) from the same manufacturer (Allergan Inc.). Different folding devices (folding blocks, folding and implantation forceps, and an injector system) were used. The IOLs were kept folded for 60 seconds; 24 hours later, scanning electron microscopy (SEM) was performed. In addition, the cartridges of the injector system were examined by SEM.
  
  
  RESULTS
  Overall, regardless of the folding and implantation instruments used, both the multifocal and monofocal IOLs had discrete surface alterations. The cartridges of the injector system had a rough surface at the tip, while the proximal portion appeared smooth.
  
  
  CONCLUSIONS
  There were no signs of lesions particularly affecting the surface of multifocal IOLs.
authors.affiliation: Department of Ophthalmology, Christian-Albrechts-University, Kiel, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Häring
authors.forename: M
authors.initials: M
authors.lastname: Winter
authors.forename: S
authors.initials: S
authors.lastname: Behrendt
mesh_terms: D004548:Elasticity; D006801:Humans; D019654:Lens Implantation, Intraocular / Q000295:instrumentation; D007910:Lenses, Intraocular; D008855:Microscopy, Electron, Scanning; D012826:Silicone Elastomers / Q000032:analysis* / Q000592:standards; D013314:Stress, Mechanical
chemical_list: D012826:Silicone Elastomers