Injection of intravitreal bevacizumab (Avastin) as a preoperative adjunct before vitrectomy surgery in the treatment of severe proliferative diabetic retinopathy (PDR)

Abstract

Purpose: To evaluate the use of preoperative intravitreal bevacizumab (IVB) in patients undergoing pars plana vitrectomy (PPV) for complications of proliferative diabetic retinopathy (PDR).

Methods: We studied 22 patients with severe PDR. A preoperative complexity score (CS) was recorded. Eleven eyes were treated with IVB, 1.25 mg, 5-7 days before PPV (group 1), and 11 eyes underwent direct PPV (group 2). Surgical time and intra-operative manoeuvres were recorded. Main outcome measure was feasibility of surgery, secondary goal was the visual and anatomic outcome at 6 months.

Results: The average CS was 5.5, and was similar in the two groups. Mean surgical time was 57 minutes in group 1 vs 83 minutes in group 2; mean tool exchanges was 27 vs 53, intraoperative bleeding 5 vs 15, endodiathermy 2 vs 9. No complications were recorded after IVB. Mean pre-operative BCVA was 1.87 logMAR in group 1 and logMAR 2.04 in group 2. Mean pre-operative BCVA was 1.87 logMAR in the bevacizumab group and 2.04 logMAR in group 2, not significantly different (p = 0.7). Mean post-operative BCVA at 6 months was 0.88 logMAR in group 1 and logMAR 2.01 in control group 2, significantly different (p = 0.01). Post-operative BVCA improved in bevacizumab group from pre-operative value (p = 0.15), while in control group there was non-significant increase (p = 0.96). Anatomical attachment was achieved in 11 patients in group 1 vs nine patients in group 2.

Conclusions: IVB administered prior to vitrectomy was well tolerated and reduced active neovascularization, thus facilitating PPV.