title: Ultrasound biomicroscopy characterization of acrylic, silicone, and polymethyl methacrylate lenses in vitro.
abstract: BACKGROUND
  This study aims to characterize the reflective properties of some commonly used intraocular lenses (IOLs) in vitro, with a particular focus on lens haptics.
  
  
  METHODS
  Six different types of IOLs, representative of silicone, acrylic, and polymethyl methacrylate (PMMA), single, multipiece, and multifocal were imaged using high-resolution ultrasound biomicroscopy (UBM).
  
  
  RESULTS
  Reflectivity patterns were distinct to the material that was being imaged irrespective of whether the part being imaged was the haptic or optic. Acrylic haptics demonstrated a single "tram-track" reduplication echo, whereas PMMA haptics showed multiple reverberation echoes off the posterior surface. The optics of various PMMA and acrylic lenses demonstrated a reflectivity pattern similar to the respective haptics made of the same material. Silicone optics displayed clear delineation with no reverberation. Both acrylic and silicone material was relatively less reflective when compared with PMMA.
  
  
  CONCLUSIONS
  With UBM imaging, the haptics of acrylic and PMMA IOLs demonstrate unique reflective patterns, depending on the material being studied. Prior knowledge of what the lens haptics and optics look like in vitro provides information that may assist in identifying and localizing misplaced intraocular lenses in vivo.
authors.affiliation: University of Ottawa Eye Institute, Ottawa, Ontario, Canada. skulkarni@ohri.ca
authors.forename: Sadhana V
authors.initials: SV
authors.lastname: Kulkarni
authors.forename: Karim F
authors.initials: KF
authors.lastname: Damji
authors.forename: Diane
authors.initials: D
authors.lastname: Chialant
mesh_terms: D000180:Acrylic Resins; D001672:Biocompatible Materials; D066298:In Vitro Techniques; D007910:Lenses, Intraocular; D033401:Microscopy, Acoustic; D008954:Models, Biological; D019904:Polymethyl Methacrylate; D012826:Silicone Elastomers
chemical_list: D000180:Acrylic Resins; D001672:Biocompatible Materials; D012826:Silicone Elastomers; D019904:Polymethyl Methacrylate