title: Correlation between posterior capsule opacification and visual function before and after Neodymium: YAG laser posterior capsulotomy.
abstract: OBJECTIVE
  To investigate the correlation between visual acuity, contrast sensitivity, and contrast sensitivity with glare source (glare sensitivity), and the degree of posterior capsule opacification (PCO) before and after neodymium:yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy.
  
  
  METHODS
  Prospective interventional case series.
  
  
  METHODS
  Eighty-four patients (90 pseudophakic eyes) scheduled to undergo Nd:YAG laser capsulotomy were recruited. Visual acuity and contrast sensitivity with and without the presence of a circular glare source (using the contrast glare tester) were measured before and after Nd:YAG laser capsulotomy. The PCO density value was measured using a Scheimpflug videophotography system. The visual functions were statistically correlated with the PCO value.
  
  
  RESULTS
  Before Nd:YAG laser capsulotomy, strong correlation existed between the PCO value and visual acuity (r = 0.728). Contrast sensitivity and glare sensitivity were also weakly correlated with the PCO value, but the correlation coefficients were smaller than that of visual acuity. After Nd:YAG laser capsulotomy, mean visual acuity, contrast sensitivity, and glare sensitivity at all visual angles improved significantly (P <.0001). After capsulotomy, no significant correlation was found between visual acuity, contrast sensitivity, or glare sensitivity and the PCO value.
  
  
  CONCLUSIONS
  Before Nd:YAG laser capsulotomy, visual functions correlated significantly with the degree of PCO. Specifically, visual acuity has a stronger association with PCO than does contrast sensitivity or glare sensitivity and therefore should be considered to reflect most accurately the degree of PCO. After capsulotomy, these visual functions improve markedly and no longer have a significant correlation with PCO.
mesh_terms: D000368:Aged; D002386:Cataract / Q000503:physiopathology* / Q000628:therapy; D002387:Cataract Extraction; D015350:Contrast Sensitivity / Q000502:physiology*; D005260:Female; D019466:Glare; D006801:Humans; D053685:Laser Therapy; D007903:Lens Capsule, Crystalline / Q000503:physiopathology* / Q000601:surgery; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D011183:Postoperative Complications / Q000503:physiopathology* / Q000601:surgery; D011446:Prospective Studies; D019591:Pseudophakia / Q000150:complications; D014792:Visual Acuity / Q000502:physiology*