AIM:To quantitatively evaluate the macular microvasculature and visual function in patients with macular edema secondary to retinal vein occlusion(RVO)by optical coherence tomography angiography(OCTA)combined with microperimetry.

METHODS: Totally 36 patients(36 eyes)with monocular RVO complicated with macular edema were enrolled, including 15 patients(15 eyes)in central retinal vein occlusion(CRVO)group and 21 patients(21 eyes)in branch retinal vein occlusion(BRVO)group(all with superior temporal vein occlusion), 15 age-matched healthy subjects(24 eyes)were included as controls. OCTA was used to scan macular retina in the range of 3mm×3mm in all three groups and measure the vascular density(VD)of superficial capillary plexus(SCP)and deep capillary plexus(DCP), the area of foveal avascular zone(FAZ)and the central retinal thicknes(CRT); the retinal mean sensitivity(RMS)at 10°was measured by MP-3 microperimetry. VD and RMS in BRVO group were further divided into lesion area(superior), non-lesion area(inferior)VD and RMS. The lesion area and non-lesion area of the control group were divided according to corresponding regions of the BRVO group. The changes of above indexes in CRVO group and BRVO group were compared with control group respectively, and the correlation between RMS and VD, CRT and FAZ areas in CRVO group and BRVO group was analyzed.

RESULTS:The overall VD(SCP and DCP)in CRVO group were lower than those in control group(t= -2.536, P=0.016; t= -8.834, P<0.001); the area of FAZ was larger than that in control group(t=3.354, P=0.002); the CRT was thicker than that in control group(t=13.888, P<0.001); the overall RMS was significantly lower than that in control group(t= -6.250, P<0.001). The overall VD(SCP and DCP)in BRVO group were decreased compared to those in control group(t= -5.186, P<0.001; t= -5.238, P<0.001); the VD of SCP and DCP in the affected sector were decreased compared to those in the corresponding sector of the control group(t= -5.611, P<0.001; t= -6.940, P<0.001); the VD in the unaffected sector was significantly less than that in the corresponding sector of the control group only in DCP, but not in SCP(t= -3.047, P=0.004; t= -1.459, P=0.156); the area of FAZ was larger than that in control group(t=2.722, P=0.011); the CRT was thicker than that in control group(t=7.764, P<0.001); the overall RMS was significantly lower than that in control group(t= -10.931, P<0.001); the RMS in both the affected sector and the unaffected sector were lower than those in the corresponding sector of the control group(t= -13.183, P<0.001; t= -8.074, P<0.001). In CRVO group,the overall VD of SCP and DCP was positively correlated with the overall RMS(r=0.571, P=0.026; r=0.813, P<0.001)and the area of FAZ and CRT was negatively correlated with the overall RMS(r= -0.621, P=0.014; r= -0.533, P=0.041). In BRVO group,the overall VD of SCP and DCP was positively correlated with the overall RMS(r=0.465, P=0.034; r=0.611, P=0.003), and the CRT was negatively correlated with the overall RMS(r= -0.547, P=0.01), while there was no correlation between the area of FAZ and the overall RMS(r= -0.421, P=0.057).

CONCLUSION: The combined application of OCTA and microperimetry can corresponding quantitatively evaluate the structure and function of macular area in patients with macular edema secondary to retinal vein occlusion, providing more detailed information for clinical decision makers to explain the disease well.