Abstract
Purpose:
To evaluate anatomic and visual acuity outcomes associated with 0.5 mg intravitreal ranibizumab (IVR) in patients with diabetic macular edema (DME) refractory to 1.25 mg intravitreal bevacizumab (IVB).
Methods:
Retrospective chart review of patients seen from April 2010 through July 2012 in a single retinal specialty practice identified 1144 eyes that had received IVB for DME. Of these, 36 eyes had been refractory to IVB, defined as persistent spectral domain optical coherence tomography (SDOCT) reading of center subfield thickness (CSFT) >300 microns, and were subsequently given IVR. Data collected include years of diabetes mellitus (DM); prior vitrectomy, panretinal photocoagulation (PRP), focal laser therapy, or intravitreal triamcinolone (IVT) use; number of IVB and IVR injections; months of IVB and IVR treatment; complications; and best corrected visual acuity (BCVA) and CSFT measurements at baseline, 1 month after first injection (early results), and 1 month after final injection of IVB and IVR (final results).
Results:
Thirty-six eyes of 32 patients with 18.8 mean years of DM received an average of 4.5 IVB injections over a mean of 7.2 months, followed by an average of 5.7 IVR injections over a mean of 8.5 months. Other results include no complications for IVB or IVR injections, 3 eyes with prior vitrectomy, 17 eyes with prior PRP, 32 eyes with prior focal laser (mean 3.3 treatments), and 10 eyes with prior IVT (mean 2.6 injections, range 5-36 months prior, mean 15 months). IVB showed significant improvement in CSFT on early results (mean ± SEM change -40 ± 18 microns in the 33 patients measured on both occasions, p=.033) but not with final results (+13 ± 18 microns, p=.48). IVR was associated with very highly significant improvement for both early (-120 microns ± 22 in the 34 patients measured on both occasions, p< .001) and final (-139 ± 22 microns, p< .001) results. With IVB, there was no significant improvement in LogMar BCVA for early (+.04 ± .06. p=.50) or final (-.05 ± .07 in the 35 patients measured on both occasions, p=.44) results. With IVR treatment, significant improvement in LogMar BCVA was not seen for early results (+.01 ± .05, p=.80) but was seen for final results (+.08 ± .03, p=.02).
Conclusions:
These data suggest that IVR may be a reasonable treatment option for patients with DME refractory to IVB.
Keywords: 499 diabetic retinopathy •
585 macula/fovea •
505 edema