Dexamethasone Intravitreal Implant Rescue Treatment for Bevacizumab Refractory Macular Edema Secondary to Branch Retinal Vein Occlusion

PURPOSE To evaluate the prognostic factors and outcomes of dexamethasone intravitreal implant (DEX implant) for intravitreal bevacizumab refractory macular edema secondary to branch retinal vein occlusion (BRVO). METHODS This was a retrospective, interventional case series. Medical records were reviewed, and a total of 38 eyes that were treated with DEX implant for macular edema secondary to BRVO that did not respond to at least two consecutive intravitreal bevacizumab injections (IBIs) were included. Best-corrected visual acuity (BCVA), central subfield macular thickness, and central subfoveal choroidal thickness were evaluated at baseline, 2 months, and 6 months after DEX implantation. RESULTS Patients had undergone an average of 6.32 ± 4.66 prior IBI treatments. The average BCVA improved from 0.53 ± 0.26 to 0.41 ± 0.25 and 0.44 ± 0.23 logarithm of the minimal angle of resolution (logMAR) at 2 and 6 months, respectively (p < 0.001). The average central subfield macular thickness was 504.00 ± 121.54 µm at baseline and changed to 293.21 ± 74.17 µm and 427.28 ± 119.57 µm at 2 and 6 months, respectively (p < 0.001 and p = 0.002). Average central subfoveal choroidal thickness was 237.46 ± 92.21 µm at baseline and changed to 204.75 ± 74.74 µm and 226.86 ± 90.77 µm at 2 and 6 months, respectively (p < 0.001 and p = 0.455). Twenty-two eyes (58%) gained ≥0.1 logMAR at 2 months, while 16 eyes showed no improvement. Low BCVA at symptom presentation, low baseline BCVA, and shorter duration of macular edema were correlated with increased BCVA after treatment. CONCLUSIONS The DEX implant improves functional and anatomical outcomes for up to 6 months in about half of the patients treated with IBI refractory macular edema secondary to BRVO, particularly in patients with low initial and baseline BCVA.