Assessment of Retinal Microvasculature and Choroidal Vascularity After Intra-arterial Chemotherapy for Retinoblastoma

Purpose To evaluate changes in retinal microvascular density and choroidal vascularity in patients with retinoblastoma (RB) after intra-arterial chemotherapy (IAC). Design Retrospective clinical cohort study. Methods This study included 12 unilateral RB eyes treated with IAC (RB tumour), 12 contralateral normal eyes (RB fellow), and 12 healthy controls. The macular retinal thickness and retinal microvascular structure, including foveal avascular zone (FAZ) area, the macular and peripapillary superficial vessel density (SVD) and deep vessel density (DVD), were measured by optical coherence tomography angiography (OCTA). The choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA) and Choroidal Vascularity Index (CVI), were measured by spectral-domain optical coherence tomography (SD-OCT). A comparison among the three groups was conducted, while the correlations among the parameters were analyzed. Results Between the three cohorts, the foveal retinal thickness, the SVD, DVD, ChT, TCA, LA, SA and CVI were significantly lower in RB tumour compared to RB fellow and the control eyes (all P<0.01). There were no significant differences in the parameters between the contralateral and control eyes. The correlation analyses indicated a significant negative correlation between the total melphalan dose and foveal and parafoveal DVD, ChT, and LA. Conclusions The retinal microvascular density and choroidal vascularity were lower in unilateral RB treated with IAC, and seemed to be related to the total melphalan dose. Moreover there were no measurable changes in the contralateral eyes.