Ultrasonic Image Feature Analysis under Deep Learning Algorithm to Evaluate the Efficacy of Drug-Coated Balloon for Treatment of Arteriosclerotic Occlusion

Table 2

The diagnostic grading standards of ultrasound [15].

Degree of arterial stenosis	PSV in the lesion (cm/s)	PSV ratio	Score
Normal	<150	<1.5 : 1	0
30%-49% (mild)	150-200	1.5 : 1-2 : 1	1
50%-75% (moderate)	200-400	2 : 1-4 : 1	2
>75% (severe)	>400	>4 : 1	3
Occlusion	No blood flow signal	—	4