title: Scanning electron microscopic characteristics  of commercially available 1- and 3-piece  intraocular lenses.
abstract: OBJECTIVE
  To evaluate commercially available 1- and 3-piece intraocular lenses (IOLs) with scanning electron microscopy (SEM).
  
  
  METHODS
  Department of Ophthalmology and Electron Microscopy Center, University Hospital Jena, Jena, Germany.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Seven +23.0 diopter IOLs of different design and material and from different manufacturers were chosen for a detailed assessment. Scanning electron microscopy was used at standardized magnifications to assess typical IOL characteristics. The particular focus was the optic edge, the optic surface, the haptic–optic junction, and the haptic.
  
  
  RESULTS
  All square-edged IOLs had a curvature radius of less than 10 μm, while the mean optic edge thickness ranged between 216 μm and 382 μm. A 360-degree square-edged boundary was present in all 3-piece IOLs and in a single 1-piece model. Relevant production remnants on the optic edge were observed in 1 case. Regarding the haptic, 3-piece IOLs had uniformly shaped fibers with a mean thickness of 177 μm ± 51 (SD) (range 116 to 220 μm). Chemical adhesives were used to attach the haptic in 1 case, where alterations of the IOL material were observed. In another case, the haptic fiber was press-fitted into the optic, which resulted in bulging of the optic profile. Inspection of surface characteristics showed wavelike patterns in 2 IOLs.
  
  
  CONCLUSIONS
  Taking clinical relevance into account, all IOLs were of high manufacturing quality. Certain attention was paid in creating a sharp optic edge. Surface irregularities of 2 IOLs were attributed to the manufacturing technique. Methods for implementing the haptic–optic junction were diverse.
authors.forename: Tobias
authors.initials: T
authors.lastname: Brockmann
authors.forename: Claudia
authors.initials: C
authors.lastname: Brockmann
authors.forename: Sandor
authors.initials: S
authors.lastname: Nietzsche
authors.forename: Eckart
authors.initials: E
authors.lastname: Bertelmann
authors.forename: Juergen
authors.initials: J
authors.lastname: Strobel
authors.forename: Jens
authors.initials: J
authors.lastname: Dawczynski
mesh_terms: D007910:Lenses, Intraocular / Q000592:standards; D008855:Microscopy, Electron, Scanning; D011474:Prosthesis Design; D011786:Quality Control