title: Association between intensity of posterior capsule opacification and visual acuity.
abstract: OBJECTIVE
  To investigate the correlation between the change in visual acuity and the difference in objective posterior capsule opacification (PCO) scores before and after neodymium:YAG (Nd:YAG) laser capsulotomy.
  
  
  METHODS
  Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
  
  
  METHODS
  Forty pseudophakic eyes of 35 patients with PCO of varying intensity were examined before and after Nd:YAG laser capsulotomy. Visual acuity was determined using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart at 4 m and the Holladay reading chart at 40 cm. The pupil diameter under reading conditions was measured each time. Digital retroillumination images of the posterior capsule were taken, and the corresponding area inside the pupil was evaluated using the Automated Quantification of After-Cataract (AQUA) automated PCO analysis program. The change in visual acuity and difference between PCO scores before and after Nd:YAG laser capsulotomy were calculated for all eyes.
  
  
  RESULTS
  The mean AQUA score (scale 0 to 10) was 3.56 before and 0.13 after Nd:YAG laser capsulotomy. The mean ETDRS visual acuity score (logMAR scale) was 0.28 and -0.07, respectively. The correlation coefficient between the differences in PCO score and distance visual acuity was 0.61 and near visual acuity, 0.62.
  
  
  CONCLUSIONS
  The objective PCO score obtained by an automated image-analysis program correlates well with the PCO-induced decrease in visual acuity when the central area (inside the pupillary aperture) of the posterior lens capsule was evaluated. Objective PCO assessment by automated image-analysis systems is, therefore, a valuable and clinically relevant method for clinical studies of the development and prevention of PCO.
authors.affiliation: Department of Ophthalmology, Medical University of Vienna, Austria.
authors.forename: Wolf
authors.initials: W
authors.lastname: Buehl
authors.forename: Stefan
authors.initials: S
authors.lastname: Sacu
authors.forename: Oliver
authors.initials: O
authors.lastname: Findl
mesh_terms: D002386:Cataract / Q000175:diagnosis / Q000503:physiopathology*; D003941:Diagnostic Techniques, Ophthalmological; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D053685:Laser Therapy; D007903:Lens Capsule, Crystalline / Q000503:physiopathology* / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology; D019591:Pseudophakia / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology*