title: Clinical evaluation of posterior capsule opacification in eyes with different small-incision intraocular lenses.
abstract: OBJECTIVE
  To present a new method to quantify posterior capsular opacity with an anterior eye segment image analyzer (EAS 1000, NIDEK).
  
  
  METHODS
  This study was comprised of patients who underwent phacoemulsification intraocular lens (IOL) implantation. Three types of IOLS, acrylic, silicone, and polymethylmethacrylate (PMMA) were allocated to 30 eyes and clinically evaluated. Patients were observed for 3 years postoperatively using an anterior eye segment image analyzer (EAS1000). Opacity was determined by calculating the area of opacity from a retroillumination image. In the retroillumination mode of analysis, the measurement was limited to a 4-mm-diameter region of the pupillary zone to eliminate the influence of anterior capsular opacity. For color map analysis, the threshold level was expressed as the color tone of 0-255 CCT (computer compatible tape). The glare disability was measured to evaluate the three types of IOLs.
  
  
  RESULTS
  The color map analysis revealed a time-related increase in the opacity level of patients receiving the PMMA IOL implant. Three years after surgery, the levels were significantly higher in the PMMA group (P < 0.01) compared to the acryl and silicone groups: acryl (17.5 +/- 3.8), silicone (18.0 +/- 6.2%), and PMMA 36.5 +/- 32.9%.
  
  
  CONCLUSIONS
  Quantitative evaluation using an anterior eye segment image analyzer is effective for observing the degree of posterior capsule opacification. The color map analysis using an anterior eye segment image correlated with the visual function revealed that the time-related increase in the opacity level was significant during the third year in patients receiving PMMA IOL implantation.
authors.affiliation: Department of Ophthalmology, Dokkyo University School of Medicine, Shimotsuga-gun, Tochigi, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Yoshida
authors.forename: Tadashi
authors.initials: T
authors.lastname: Senoo
authors.forename: Fukumi
authors.initials: F
authors.lastname: Fujikake
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Obara
mesh_terms: D000180:Acrylic Resins; D000368:Aged; D002386:Cataract / Q000175:diagnosis*; D003941:Diagnostic Techniques, Ophthalmological; D006801:Humans; D007903:Lens Capsule, Crystalline / Q000473:pathology*; D019654:Lens Implantation, Intraocular / Q000009:adverse effects; D007910:Lenses, Intraocular; D019060:Minimally Invasive Surgical Procedures; D018918:Phacoemulsification; D019904:Polymethyl Methacrylate / Q000009:adverse effects; D011183:Postoperative Complications / Q000175:diagnosis*; D012826:Silicone Elastomers / Q000009:adverse effects; D014792:Visual Acuity
chemical_list: D000180:Acrylic Resins; D012826:Silicone Elastomers; D019904:Polymethyl Methacrylate