Abstract
Purpose :
Vascular endothelial growth factor (VEGF) receptor inhibitors can be used to fabricate a rat model that presents with a retinopathy of prematurity (ROP)-like fundus (Nakano et al., 2016). This model of ROP is developed using oxygen-induced retinopathy (OIR). The aim of the present study was to determine the association between the ROP-like fundus and the fundus blood flow.
Methods :
This study enrolled a control group of 33 rats and an experimental group of 31 rats, which were subcutaneously administered with a VEGF receptor inhibitor (KRN633; anti-VEGF group) at seven and eight (postnatal) days of age. Subsequently, at two and three weeks of age, the ocular blood flow was measured with Laser Speckle Flowgraphy-Micro and compared between the two groups. After the measurement at three weeks of age, flat-mounted retina specimens were prepared and used to examine the correlations of retinal arterial tortuosity and the avascular region with the blood flow.
Results :
At three weeks of age, the mean blur rate (MBR) of the anti-VEGF group was significantly higher than that of the control group (p = 0.03). Moreover, the rate of increase in MBR from two to three weeks of age positively correlated with the retinal arterial tortuosity (r=0.50 p=0.0039).
Conclusions :
The MBR of the anti-VEGF group at three weeks of age was significantly higher than that of the control group, identical to a previous experiment that measured the blood flow in OIR. Moreover, higher rates of increase in MBR from two to three weeks of age were associated with greater retinal arterial tortuosity, suggesting that blood flow was higher in the anti-VEGF group than in the control group. Although the reproducibility of this study’s results need to be confirmed, they indicate that the pathology of rats with anti-VEGF drug-induced ROP-like fundi correlates with the fundus blood flow. Therefore, in terms of the ocular blood flow, the rat model in the present study can be used as a new model of ROP.
This is a 2021 ARVO Annual Meeting abstract.