The Application Of Color Doppler Ultrasonography In Symptomatic And Asymptomatic Cas Patients Having Stent Implantation

Objective: The purpose of the research was to study the hemodynamics of carotid artery stenosis patients by comparing the ultrasonic parameters between the symptomatic and asymptomatic patients before and after the stent treatment, and to provide the clinical guidance for the preoperative evaluation for stent implantation.Methods: 43 carotid artery stenosis patients were enrolled including 34 males and 9 females, aged from 41-87 y. The 43 cases of carotid artery stenosis70%, were confirmed by DSA and CTA examination, and underwent stent placement. 26 patients(M 20, F 6, mean age ? SD, 62 ? 10 y) had obvious symptoms, while the other 17 patients(M 14, F 3, mean age?SD, 67?10 y) did not have obvious symptoms. All of the patients had the Color Doppler ultrasound examination before and after stenting. PSV and RI of the internal carotid artery on both the normal side and the contralateral side were measured and the ratios of PSV and RI(rPSV and rRI) for the injured side to the normal side were calculated. The influence of carotid artery stenting on symptomatic and asymptomatic patients was analysed.Results: For symptomatic patients, rPSV and rRI were improved significantly after the stenting. rPSV decreased from 3.18 to 1.18(P<0.001)and rRI increased from 0.90 to 0.97(P<0.05). While for the asymptomatic patients, after stent treatment rPSV decreased from 4.13 to 1.24 with statistical significance(P<0.001), but rRI did not show significant improvement(P=0.68). Before and after the stent treatment, rRI for symptomatic patients was always much lower than asymptomatic patients.However, rPSV had no significant difference between the symptomatic and asymptomatic patients.Conclusion:1 Color Doppler ultrasonography has good clinical application value in diagnosis of carotid stenosis;2 The rRI values of the most patients with symptomatic carotid stenosis were significantly higher after CAS;3 The rRI values of the most patients with asymptomatic carotid stenosis were not significantly changed after CAS;4 The rRI values of the symptomatic patients were significantly lower than those in the asymptomatic group before CAS.