Prospective study of morphologic and functional parameter changes post intravitreal therapy for macular edema

Purpose Retinal sensitivity (RS) can be a valuable indicator of retinal function in response to intravitreal steroid or anti-VEGF treatment in the eyes with diabetic macular edema (DME), macular edema post retinal vein occlusion (RVO), or uveitis. Methods This prospective longitudinal study included 68 patients (96 eyes) with macular edema (ME) secondary to diabetes mellitus (42 eyes), uveitis (36 eyes), or RVO (18 eyes). In addition to best corrected visual acuity (BCVA) and retinal thickness, Nidek MP1 microperimetry was used to quantify RS at baseline visit and to look at the mean difference (MD) at 3-6 months and 1-2 years post intravitreal therapy with corticosteroids or anti-VEGF. Results There was a significant negative correlation between the central RS and BCVA (r = - 0.47, p < 0.001), including DME (r = - 0.42, p = 0.006) and uveitis (r = - 0.60, p < 0.001), but not RVO (r = - 0.37, p = 0.12). At 2-year follow-up, the overall CST was reduced from baseline (MD - 147 mu m, 95% C.I - 192 to - 102, p < 0.001) with improved BCVA (MD - 0.12 LogMAR, 95% C.I - 0.23 to - 0.01, p = 0.01), but no improvement in the RS in any of the disorders. Both anti-VEFG and steroid groups showed significant improvement in CST at 2 years from baseline (MD - 101 mu m, p = 0.001 and - 167 mu m, p < 0.001, respectively) with only improvement in BCVA among anti-VEGF group (MD - 0.16 LogMAR, 95% C.I - 0.26 to - 0.07, p = 0.008). Conclusion The long-term follow-up of ME cases did not show a significant improvement in RS following treatment even with reduced macular thickness at 2-year follow-up.