Improvement in visual outcomes in diabetic macular edema through the reduction of macular thickness fluctuations using the 0, 19 mg fluocinolone acetonide implant

PURPOSE: This study aimed to assess the effectiveness of 0.19-mg fluocinolone acetonide intravitreal (FAc) implant to control retinal thickness fluctuations (RTF) in diabetic macular edema (DME) and its effect on best-corrected visual acuity (BCVA). METHODS: The RIVER study was a multicenter, retrospective, non-interventional study analyzing data of the Retina.pt portuguese national registry in DME. Retinal thickness was assessed using the spectral domain optical coherence tomography (SD-OCT). The primary endpoint was the assessment of RTF along the follow-up, through the combined measurement of retinal thickness amplitude (RTA), retinal thickness standard deviation (RTSD), and central subfield thickness area under the curve (CST-AUC). Eyes were stratified into quartiles (Q) and median-split according to these variables. RESULTS: The mean follow-up time after the FAc implantation was 82 ± 26, 96 months. From baseline to last follow-up visit after the implant, mean RTA decreased from 187.6±150.4 to 151.6±126.4 µm (p=0.1204), mean RTSD significantly reduced from 96.3±78.1 to 60.8±57.3 µm (p=0.0032) and mean CST-AUC significantly reduced from 446 to 349 µm (p<0.0001). BCVA significantly improved in eyes with RTA Q1, Q2, Q3 (p<0.05); eyes with RTSD Q1, Q2, and Q3 (p<0.05); and eyes with CST-AUC Q1, Q2, and Q3 (p<0.05). According to the median split, eyes with RTA and RTSD < to median showed greater BCVA improvement. CONCLUSIONS: Retinal thickness fluctuation was significantly reduced after the Fc implant. Moreover, a lower retinal thickness variability tended to be associated with better visual outcomes.