Tomographic 3D ultrasound for grading stenosis of superficial femoral artery.

Abstract

Treatment decision of lower extremity peripheral arterial disease (PAD) is governed by the severity of stenosis. Tomographic 3D ultrasound (t3DUS) is a reliable imaging technique for measuring vessel stenosis. In this study we attempted to provide a precise measurement of superficial femoral artery (SFA) stenosis using t3DUS in patients with PAD. t3DUS was used to measure maximum stenosis percentage in SFA from 50 patients with lower extremity PAD. The maximum stenosed segment in SFA was defined using Duplex 2DUS aliasing was noted. The peak systolic velocity (PSV) was measured at the maximum stenotic site and proximal to aliasing for calculating the velocity ratio. The association between blood flow velocity ratio and the degree of stenosis measured using Duplex 2DUS and t3DUS, respectively, was assessed using Spearman rank correlation. There was a strong positive correlation between velocity ratio and degree of stenosis in SFA measured using t3DUS (correlation value (r) = 0.99, p < 0.001). The correlation between Stenosis percentage and velocity ratio in SFA are as followed: <50:<2; 50-54:2-2.4; 55-59:2.5-2.9; 60-64:3-3.4; 65-69:3.5-3.9; 70-74:4-4.4; 75-79:4.5-4.9; >80:>5.