ABSTRACT
Objective To investigate the value of color Doppler flow imaging(CDFI) in diagnosing lower limb artery in-stent restenosis (ISR), and to provide the evidences for clinical application. Methods Patients with lower limb artery percutaneous transluminal stent insertion in 12 months were enrolled in this study and divided into two groups, CT angiography (CTA) or digital subtraction angiography (DSA) was applied to diagnose ISR, 31 patients with 47 stenting which were diagnosed ISR was named as restenosis group, 63 patients with 89 stenting which were diagnosed no ISR was named as no stenosis group, and 30 normal person was enrolled and named as normal control group. Ultrasonic characteristics and peak systolic blood flow velocity (PSV), systolic blood flow acceleration time (AT) of proximal part, inner stents, distal part were recorded in restenosis group and no stenosis group, then compared with data in normal control group. Regression and receiver operator (ROC) curve were applied to analyse the correlation between PSV and AT. Results PSV of no stenosis group in common femoral artery, femoral artery, superifcial, popliteal artery stent respectively were (146.71±35.59) cm/s, (120.11±25.67) cm/s, (96.44±32.87) cm/s. PSV of normal control group in common femoral artery, femoral artery, superifcial, popliteal artery respective were (119.67±15.34) cm/s, (91.17±15.09) cm/s, (71.13±21.23) cm/s. There was statistically signiifcant difference between the two groups (t=2.457, 2.459, 2.321, all P0.05). PSV of restenosis group in proximal part, restenosis part, distal part respectively were (87.67±23.34) cm/s, (218.17±72.09) cm/s, (54.13±21.23) cm/s. PSV of no stenosis group in proximal part, inner stents, distal part respectively were (91.71±25.59) cm/s, (131.11±45.67) cm/s, (96.44±32.87) cm/s. There was statistically significant difference between restenosis part/inner stents, distal part (t=3.412, 3.511, both P0.05). AT of restenosis group in proximal part, restenosis part, distal part respectively were (98.31±14.09) ms, (109.54±21.03) ms, (158.23±45.21) ms. AT of no stenosis group in proximal part, inner stents, distal part respectively were (84.98±13.77) ms, (86.34±19.36) ms, (83.77±17.05) ms. There was statistically signiifcant difference between restenosis part/inner stents, distal part (t=2.319, 3.610, both P0.05). ROC curve showed that in ISR lower limb artery, PSV>168 cm/s had a sensitivity of 89.4%, speciifcity of 92.1%, the area under the ROC curve was 0.949;AT>127 ms, had a sensitivity of 86.8%, speciifcity of 98.0%, the area under the ROC curve was 0.867. Conclusions CDFI can detect the changes of PSV and AT, ISR can be detected and diagnosed earlier in lower limb artery. By combining PSV>168 cm/s with AT>127 ms, the value of ISR diagnosis can be increased.