title: Retinal redetachment after silicone oil removal in proliferative vitreoretinopathy: a prognostic factor analysis.
abstract: OBJECTIVE
  To determine the prognostic factors associated with retinal redetachment after 1300-centistokes silicone oil removal in rhegmatogenous retinal detachments (RDs) associated with grade C proliferative vitreoretinopathy (PVR).
  
  
  METHODS
  Nonrandomized, retrospective, comparative interventional trial.
  
  
  METHODS
  One hundred and forty-seven eyes with RD and grade C PVR treated with silicone oil tamponade, with subsequent silicone oil removal, in an institutional setting. Main outcome measures included anatomic success, defined as complete retinal attachment after silicone oil removal, and best-corrected visual acuity (BCVA) after silicone oil removal.
  
  
  RESULTS
  Silicone oil was removed after a mean tamponade period of 12.4+/-9.8 months. The mean follow-up after silicone oil removal was 22.1+/-18.7 months (range, 6.0 to 71.0 months). The retina remained attached in 120 eyes after oil removal. The overall anatomic success rate was 81.6%+/-3.2%. Logistic regression showed that an increased number of previous unsuccessful RD surgeries (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.19 to 0.80; P=.010) and longer axial lengths (OR, 0.42; 95% CI, 0.15 to 0.87; P=.032) were associated with a lower anatomic success rate. Previous vitrectomy, previous scleral buckling procedure, 12% perfluoropropane-air exchange immediately after silicone oil removal, and duration of silicone oil tamponade were not statistically associated with the anatomic success rate. Anatomic success was associated with a significantly better BCVA (1.169+/-0.475 vs 1.520+/-0.381 logarithm of the minimum angle of resolution; P<.001).
  
  
  CONCLUSIONS
  The number of previous surgeries and axial length, rather than the nature of the previous surgical procedures, were significant prognostic factors for anatomic success after silicone oil removal.
authors.affiliation: Hong Kong Eye Hospital, and the Eye Institute, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong.
authors.forename: Robert F
authors.initials: RF
authors.lastname: Lam
authors.forename: Benson T O
authors.initials: BT
authors.lastname: Cheung
authors.forename: Can Y F
authors.initials: CY
authors.lastname: Yuen
authors.forename: David
authors.initials: D
authors.lastname: Wong
authors.forename: Dennis S C
authors.initials: DS
authors.lastname: Lam
authors.forename: Wico W
authors.initials: WW
authors.lastname: Lai
mesh_terms: D004322:Drainage / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011379:Prognosis; D012008:Recurrence; D012163:Retinal Detachment / Q000209:etiology* / Q000601:surgery; D012307:Risk Factors; D012591:Scleral Buckling; D012827:Silicone Oils / Q000009:adverse effects*; D014792:Visual Acuity; D014821:Vitrectomy; D018630:Vitreoretinopathy, Proliferative / Q000150:complications / Q000601:surgery*
chemical_list: D012827:Silicone Oils