Abstract
Purpose:
To assess the best timing of intravitreal Bevacizumab ivB for the highest efficacy and safety in assisting pars plana vitrectomy PPV in proliferative diabetic retinopathy PDR.
Methods:
The retrospective study reviewed the recordings of 83 eyes with PDR undergoing PPV assisted by ivB (1.25 mg/0.05 ml) injected 2 weeks, 3-4 days or 5 hours before- or at the end of surgery. The treated group included: 8 complications of cataract surgery and macular edema, 48 PDR and vitreous hemorrhage VH, 27 PDR+VH and tractional retinal detachment TRD. Treatment efficacy was evaluated by assessing the visual acuity (VA) at 3 months postoperatively, the improved intraoperative conditions (better visibility, decrease of intraoperative bleeding, facilitation of dissection by already detached and fibrotic posterior hyaloid and membranes) and postoperative immediate rebleeding. The safety of the procedures was appreciated by assessing the incidence of retinal detachment at 3 months postoperatively. A group of 23 eyes with PDR+VH±TRD operated by standard PPV was used as control.
Results:
Postoperative VA was improved in 81.3% of treated eyes versus 60.9% controls, was stable in 4% treated eyes as compared to 13% controls, and get worse in 14.7% injected eyes versus 26.1% controls not receiving ivB. The intraoperative conditions were better in eyes receiving ivB preoperatively, with no difference between the 3 groups with different preoperative allotted time for Bevacizumab action. These advantages were not noticed in controls. Because of large variety of clinical conditions even between eyes included in the same clinical type of PDR±VH±TRD, an accurate statistical interpretation is difficult. The incidence of postoperative immediate bleeding was lower in injected eyes, 32.5% as compared to controls, 52.2%. The incidence of postoperative retinal detachment was higher in controls, 34.8% compared to 19.3% in treated eyes. However, in treated group, the incidence of RD was higher in the eyes receiving ivB at the end of surgery, 36.8% as compared to 14.1% in preoperatively injected eyes.
Conclusions:
IvB is a very useful tool to assist the PPV in PDR as it improves the postoperative VA and intraoperative conditions, with less risk of intra- and postoperative complications. The safest time for perioperative administration seems to be preoperatively.
Keywords: 762 vitreoretinal surgery