Quantitative Analysis of Retinal Microvascular Changes after Conbercept Therapy in Branch Retinal Vein Occlusion Using Optical Coherence Tomography Angiography

Abstract

<b><i>Purpose:</i></b> To quantitatively evaluate microvascular changes in eyes with macular oedema due to branch retinal vein occlusion (BRVO) using optical coherence tomography angiography (OCTA) before and after intravitreal conbercept injection and the correlation of such changes with best-corrected visual acuity (BCVA) and retinal thickness. <b><i>Methods:</i></b> Twenty-eight eyes of 28 patients treated with a single intravitreal injection of conbercept for macular oedema due to BRVO were included in this study. The automatically measured values of the vessel density in the superficial (SCP) and deep retinal capillary plexus (DCP), the foveal avascular zone (FAZ) area, the FAZ perimeter, the vessel density within a 300 μm wide ring surrounding the FAZ (FD-300), the acircularity index (AI), the choriocapillaris flow area and the retinal thickness were obtained via OCTA before and at 1 month after initial injection and compared with those of age- and sex- matched healthy subjects. <b><i>Results:</i></b> In BRVO eyes, the vascular density in the SCP and DCP, the FD-300 and the flow area of choriocapillaris were significantly lower than those in healthy eyes, while the AI and the retinal thickness were significantly increased. After treatment, the retinal thickness in eyes with BRVO was significantly decreased in all quadrants, and the mean BCVA dramatically increased from 20/162 to 20/78 (<i>p</i> = 0.0017). The mean flow area of choriocapillaris significantly improved after treatment. Moreover, negative correlations between the logMAR BCVA and the whole vascular density in the SCP and DCP as well as the flow area of choriocapillaris were observed. <b><i>Conclusion:</i></b> OCTA enables non-invasive, layer-specific and quantitative assessment of microvascular changes in eyes with BRVO before and after treatment, and it can be used as a valuable imaging tool for the evaluation of the follow-up in BRVO patients.

Changes in Macular Microvascular Structure in Macular Edema Secondary to Branch Retinal Vein Occlusion Treated with Antivascular Endothelial Growth Factor for One Year

“…OCTA, as a novel dyeless technology, is instantaneous, fast, noninvasive, and high resolution, and it clearly shows retinal vessels of different levels and enables a direct view of the retinal capillary plexus (DCP), which is involved in BRVO and is not visible on fluorescein fundus angiography (FFA); additionally, the observation of abnormal vessels is clearer than in traditional fluorescein fundus angiography (FFA) [6]. e retinal vascular density (VD) and the foveal avascular zone (FAZ) of the macular fovea are measured quantitatively for different layers [7,8]. Several studies have indicated that OCTA can be used to evaluate microvascular changes in patients with BRVO before and after anti-VEGF treatment and as a valuable imaging tool for the follow-up evaluation in BRVO eyes [7][8][9][10][11].…”

“…e retinal vascular density (VD) and the foveal avascular zone (FAZ) of the macular fovea are measured quantitatively for different layers [7,8]. Several studies have indicated that OCTA can be used to evaluate microvascular changes in patients with BRVO before and after anti-VEGF treatment and as a valuable imaging tool for the follow-up evaluation in BRVO eyes [7][8][9][10][11]. However, a few studies have reported the correlation of anatomy and visional function in BRVO eyes evaluated with OCTA.…”

Evaluation of Microvascular Structure Changes after Conbercept Treatment on Macular Edema Secondary to Retinal Vein Occlusion

“…However, the FAZ area had no significant differences in eyes with iRVO, which may be due to the ischemia which had caused nonreversible damage of retinal capillary in iRVO patients. Deng et al [23] reported that the FAZ area was statistically unchanged during the course of 1 month of conbercept therapy in RVO patients. One of the reasons may be due to the limited sample size and short observation period.…”

Retinal Vascularization Analysis on Optical Coherence Tomography Angiography before and after Intraretinal or Subretinal Fluid Resorption in Exudative Age-Related Macular Degeneration: A Pilot Study

“…For example, in chronic diabetic ME (DME), cystoid spaces co-localized with capillary loss areas and no reperfusion occurred after DME resolution [9]. The same findings have been observed for retinal vein occlusion (RVO) [10]. However, unlike DME and RVO, macular vessel density after the resolution of an acute pseudophakic cystoid ME did not differ from the control eyes [11].…”

“…Surprisingly, there is a significant increase in MPD in eyes with IRF after exudation resorption, meaning that a reperfusion of the cystic area does occur, in contrast to vaso-occlusive diseases. Indeed, in DME and RVO, it has been shown that MPD does not increase after IRF resolution [9,10].…”