AUG 17, 2020
This study investigates the characteristics of patients undergoing anti-VEGF injections for residual or recurrent diabetic macular edema (DME) in the first year after receiving a fluocinolone acetonide implant.
This prospective cohort study of pseudophakic patients with refractory DME included 94 eyes of 66 patients who received a fluocinolone implant (Iluvien) for DME. Study outcomes included risk factors for administration of anti-VEGF, the interval between fluocinolone injection and the first anti-VEGF treatment and the number of anti-VEGF doses required to maintain DME resolution. Beginning at 4 months, patients received either aflibercept or ranibizumab 0.5 mg if persistent edema was present. The primary goal of the study was to compare baseline characteristics between patients with and without persistent DME.
Eighteen eyes required anti-VEGF injections. These patients tended to be significantly older (P=0.03), had a thicker baseline central macular thickness which persisted over the entire follow-up period (P<0.001) and were less likely to have received prior panretinal photocoagulation (PRP). The interval from fluocinolone implant to anti-VEGF treatment was longer in patients previously treated with macular laser or dexamethasone implants.
There are several limitations of this study. It is difficult to establish whether the anti-VEGF agents had a true effect in addition to the fluocinolone implant or whether there was a delayed response to the implant. Widefield angiography would have helped to explain whether peripheral nonperfusion was a factor for persistent edema in those patients who had not received PRP. Understanding the timing of recent dexamethasone implants would also be helpful because some of the edema may have been due to the implant wearing off. In addition, the use of both aflibercept and ranibizumab adds more noise to the data. The number of subjects receiving anti-VEGF injections was low, making it difficult to interpret the significance.
The low percentage of patients who required anti-VEGF agents to control recalcitrant DME supports the data presented in the FAME trial. This study suggests that the implant is less successful in older patients and those who have not received PRP. Overall, the fluocinolone implant is infrequently used for the treatment of DME. These findings suggests that it should be considered in difficult cases.