title: The adjunctive use of pre-operative intravitreal bevacizumab in the setting of proliferative diabetic retinopathy.
abstract: OBJECTIVE
  To evaluate the efficacy of pre-operative intravitreal bevacizumab injection on the rate of postoperative vitreous hemorrhage in patients undergoing vitrectomy for complications of proliferative diabetic retinopathy.
  
  
  METHODS
  Consecutive retrospective comparative cohort study. Forty eyes of 37 patients who received pre-operative intravitreal bevacizumab 1.25 mg were compared to a similar group of 44 eyes of 44 patients who had undergone vitrectomy surgery prior to the availability and widespread use of pre-operative intravitreal bevacizumab. The primary outcome measure was the incidence of post-vitrectomy hemorrhage at one week after surgery. Secondary outcome measures included are postoperative vitreous hemorrhage at one month and changes in the best-corrected visual acuity (BCVA). For statistical analysis, the paired Student's t-test and Fisher's exact test were used.
  
  
  RESULTS
  Four out of 40 eyes (10%) pretreated with intravitreal bevacizumab vs. 12 of 44 eyes (27%) not pretreated with intravitreal bevacizumab had a clinically significant postoperative vitreous hemorrhage at one week. The mean best-corrected visual acuity (BCVA) in bevacizumab group improved from a mean of hand motions to a mean of 20/300 at 1 month (range: 20/25-light perception;p< .001) and mean BCVA in the non-injected group improved from preoperative mean of hand motion to 20/200 at one month follow-up (range: 20/25-no light perception;p< .001). In both groups, 4 patients (12%) needed repeat vitrectomy.
  
  
  CONCLUSIONS
  There is a trend to reduced incidence of early post-vitrectomy hemorrhage in patients undergoing vitrectomy for complications of proliferative diabetic retinopathy that have been pre-treated with intravitreal bevacizumab 1 week prior to surgery.
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada; Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Al-Kharashi
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada; Department of Ophthalmology, Azerbaijan Medical University, Baku, Azerbaijan.
authors.forename: Tural
authors.initials: T
authors.lastname: Galbinur
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada; Donald K. Johnson Eye Centre Toronto Western Hospital, University Health Network, 399 Bathurst St., Toronto, ON M5T 2S8, Canada.
authors.forename: Efrem D
authors.initials: ED
authors.lastname: Mandelcorn
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada; Department of Ophthalmology, St. Michael's Hospital, 801-61 Queen St E, Toronto, ON M5C 2T2, Canada.
authors.forename: Rajeev H
authors.initials: RH
authors.lastname: Muni
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada.
authors.forename: Mir
authors.initials: M
authors.lastname: Nabavi
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada; The John and Liz Tory Eye Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Room M1-202a, Toronto, ON M4N 3M5, Canada.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Kertes
keywords: Bevacizumab; Proliferative diabetic retinopathy; Vitrectomy; Vitreous hemorrhage