title: Intravitreal long-acting gas in the prevention of early postoperative vitreous hemorrhage in diabetic vitrectomy.
abstract: OBJECTIVE
  To evaluate the hemostatic effects of intravitreal infusion of 10% C3F8 in patients undergoing diabetic vitrectomy on the occurrence of early postoperative recurrent vitreous hemorrhage.
  
  
  METHODS
  Prospective, randomized, observational case series.
  
  
  METHODS
  Sixty-one eyes (59 patients) that underwent primary pars plana vitrectomy for complications of proliferative diabetic retinopathy from September 2004 to April 2005, with postoperative retinal reattachment > or = 3 months and follow-up > 6 months were enrolled.
  
  
  METHODS
  Sixty-one cases were randomly divided into either group 1 (intravitreal 10% C3F8 infusion at the end of surgery) or group 2 (no intravitreal gas). Ultrasound biomicroscopy (UBM) examination of the 3 sclerotomy sites was performed at > or = 2 months postoperatively. Demographic data, history, intraoperative findings, and management of recurrent vitreous hemorrhage were recorded.
  
  
  METHODS
  Initial time to vitreous clearing (ITVC), percentage of prolonged ITVC (> 5 weeks), and early (< or = 4 weeks) versus late (> 4 weeks) manifest postoperative recurrent vitreous hemorrhage in groups 1 and 2 were compared to determine the effects of 10% C3F8 on prevention of early recurrent vitreous hemorrhage. Multiple logistic regression analyses were performed to examine risk factors related to early recurrent vitreous hemorrhage.
  
  
  RESULTS
  Group 1 ITVC was 13.2+/-9.6 days, and group 2 ITVC was 11.3+/-11.1 days (P = 0.26). Prolonged ITVC (> 5 weeks) in each group was 1/31 (3.2%) and 2/30 (6.7%; P = 0.53). Early manifest recurrent vitreous hemorrhage rates in groups 1 and 2 were 0/31 (0%) and 5/30 (16.7%), respectively (P = 0.02). Early manifest recurrent hemorrhage plus prolonged ITVC in the 2 groups were 1/31 (3.2%) and 7/30 (23.3%), respectively (P = 0.02). The incidences of elevated intraocular pressure, iris neovascularization, and significant cataract formation among the 2 groups were too low to detect statistical significance. No evidence of fibrovascular ingrowth was found by UBM examination in either group. Multiple logistic regression analyses in non-gas-infused cases showed that an increased extent of membrane peeling raised the possibility of significant early vitreous rebleeding.
  
  
  CONCLUSIONS
  Intraocular tamponade with 10% C(3)F(8) may be a useful adjunct to vitrectomy for proliferative diabetic retinopathy in the reduction of early postoperative recurrent vitreous hemorrhage.
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan. Chungmay@ha.mc.ntu.edu.tw
authors.forename: Chung-May
authors.initials: CM
authors.lastname: Yang
authors.forename: Po-Ting
authors.initials: PT
authors.lastname: Yeh
authors.forename: Chang-Hao
authors.initials: CH
authors.lastname: Yang
mesh_terms: D003922:Diabetes Mellitus, Type 1 / Q000150:complications; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D003930:Diabetic Retinopathy / Q000601:surgery*; D005260:Female; D005466:Fluorocarbons / Q000008:administration & dosage*; D005500:Follow-Up Studies; D006801:Humans; D007263:Infusions, Parenteral; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000517:prevention & control*; D011446:Prospective Studies; D055502:Secondary Prevention; D014792:Visual Acuity; D014821:Vitrectomy; D014822:Vitreous Body; D014823:Vitreous Hemorrhage / Q000517:prevention & control*
chemical_list: D005466:Fluorocarbons; C042852:perflutren