Fig. 3
![Fig. 3](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12882-020-01968-6/MediaObjects/12882_2020_1968_Fig3_HTML.png)
The sonogram was obtained immediately after PTA and the AVF outflow was scored 3. Doppler measurement was performed through a glove-made water pad and the Doppler angle was 52°. The photograph showed the probe was placed on a glove-made water pad during Doppler measurement