title: Cumulative probability of neodymium: YAG laser posterior capsulotomy after phacoemulsification.
abstract: OBJECTIVE
  To retrospectively analyze the cumulative probability of neodymium:YAG (Nd:YAG) laser posterior capsulotomy after phacoemulsification and to evaluate the risk factors.
  
  
  METHODS
  Ando Eye Clinic, Kanagawa, Japan.
  
  
  METHODS
  In 3997 eyes that had phacoemulsification with an intact continuous curvilinear capsulorhexis, the cumulative probability of posterior capsulotomy was computed by Kaplan-Meier survival analysis and risk factors were analyzed using the Cox proportional hazards regression model. The variables tested were sex; age; type of cataract; preoperative best corrected visual acuity (BCVA); presence of diabetes mellitus, diabetic retinopathy, or retinitis pigmentosa; type of intraocular lens (IOL); and the year the operation was performed. The IOLs were categorized as 3-piece poly(methyl methacrylate) (PMMA), 1-piece PMMA, 3-piece silicone, and acrylic foldable.
  
  
  RESULTS
  The cumulative probability of capsulotomy after cataract surgery was 1.95%, 18.50%, and 32.70% at 1, 3, and 5 years, respectively. Positive risk factors included a better preoperative BCVA (P =.0005; risk ratio [RR], 1.7; 95% confidence interval [CI], 1.3-2.5) and the presence of retinitis pigmentosa (P<.0001; RR, 6.6; 95% CI, 3.7-11.6). Women had a significantly greater probability of Nd:YAG laser posterior capsulotomy (P =.016; RR, 1.4; 95% CI, 1.1-1.8). The type of IOL was significantly related to the probability of Nd:YAG laser capsulotomy, with the foldable acrylic IOL having a significantly lower probability of capsulotomy. The 1-piece PMMA IOL had a significantly higher risk than 3-piece PMMA and 3-piece silicone IOLs.
  
  
  CONCLUSIONS
  The probability of Nd:YAG laser capsulotomy was higher in women, in eyes with a better preoperative BCVA, and in patients with retinitis pigmentosa. The foldable acrylic IOL had a significantly lower probability of capsulotomy.
authors.affiliation: Department of Ophthalmology, Kugayama Hospital, Ibaraki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ando
authors.forename: Nobuyo
authors.initials: N
authors.lastname: Ando
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Oshika
mesh_terms: D000180:Acrylic Resins; D000368:Aged; D000369:Aged, 80 and over; D019923:Capsulorhexis; D005260:Female; D006801:Humans; D053685:Laser Therapy; D007903:Lens Capsule, Crystalline / Q000473:pathology / Q000601:surgery*; D019654:Lens Implantation, Intraocular; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification; D019904:Polymethyl Methacrylate; D011183:Postoperative Complications / Q000473:pathology / Q000601:surgery*; D011336:Probability; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012826:Silicone Elastomers; D016019:Survival Analysis; D014792:Visual Acuity
chemical_list: D000180:Acrylic Resins; D012826:Silicone Elastomers; D019904:Polymethyl Methacrylate