Abstract
Purpose: :
To compare efficacy of intravitreal ranibizumab (IVR) vs. additional panretinal photocoagulation (PRP) for persistent retinal neovascularization (NV) after PRP for proliferative diabetic retinopathy (PDR). Concomitant macular edema (ME) pre/post treatment was also evaluated.
Methods: :
Open-label, prospective, Phase I/II study of IVR in patients with persistent (>3 months) retinal NV secondary to PDR previously treated with PRP (>/=1200 500µm burns). Patients were randomly assigned to either 0.5mg IVR or additional PRP (up to 500 200-500µm burns). ETDRS best corrected visual acuity (BCVA), Optos color photography and fluorescein angiogram (FA), and optical coherence tomography (OCT) were done at enrollment, weekly for first month, then monthly for 5 months. Patients with tractional retinal detachments (TRD), uncontrolled glaucoma, and pregnancy were excluded, as were patients with history of previous anti-VEGF intravitreal injections and/or vitrectomy. Primary outcome measures included percentage change of area of NV as measured in pixels by Optos FA, and percentage change of ME on OCT. Secondary outcome measures were mean change in BCVA, and occurrence rate of complications from PDR, including vitreous hemorrhage (VH), iris NV and TRD.
Results: :
Nine patients were randomized to receive IVR vs. additional PRP; six completed follow-up and were used for analysis. Four received IVR and two received additional PRP. The area of NV in IVR group decreased by 83.8% at 4 weeks and increased by 11.3% by 4-6mo. In PRP group, the area of NV increased by 52.6% at 4 weeks and by 55.4% at 4-6mo. At 4 weeks, ME decreased by 2.4% in IVR group and by 8.4% in PRP group. At 6 months ME increased by 54.1% in IVR group and decreased by 2.1% in PRP group. Mean change in BCVA at 1mo showed 2 lines gained from baseline in IVR group and no change in PRP group. At 6 months, IVR group had gained 3 lines from baseline and the PRP group had gained 2 lines. There were no complications from PDR in IVR group. One patient in PRP group developed VH.
Conclusions: :
This pilot study was limited by small numbers, but IVR in patients with persistent NV despite PRP appeared successful in improving VA and reducing NV to a greater extent and sooner than additional PRP. Concomitant ME in patients treated with IVR improved minimally with use of IVR.
Clinical Trial: :
http://www.clinicaltrials.gov NCT00606138
Keywords: diabetic retinopathy • neovascularization • injection