下肢动脉闭塞性疾病低剂量CT灌注成像的可行性研究

Feasibility Study of Low Dose CT Perfusion Imaging in Peripheral Arterial Occlusive Disease of Lower Extremities

目的:探讨低剂量CT灌注(CTP)成像在下肢动脉闭塞性疾病(PAOD)临床应用中的可行性。方法:前瞻性收集%例临床诊断PAOD患者,按照不同管电压及管电流随机分为A组(120kV,1OOmAs)、B组(80kV,100mAs)、C组(80kV,120mAs),行下肢CTP检查,均联合运用迭代重建降噪技术。采用单因素方差分析比较3组图像质量指标、灌注参数值及辐射剂量的差异。结果:①76例148条下肢被纳入研究,3组患者临床资料的差异无统计学意义CP>0.05),具有可比性。②3组图像客观质量指标的差异有统计学意义(P<0.05),A组和C组的SNR值、CNR值、主观质量评分均优于B组,A、C组与B组差异有统计学意义(P<0.001)。③3组灌注参数的差异无统计学意义(P>0.05)。④3组辐射剂量差异有统计学意义(P<0.05),C组较A组降低了49%。结论:对PAOD患者采用80kV、120mAs进行下肢低剂量CTP检查是可行的,能在不影响灌注参数的情况下显著降低辐射剂量,同时保证图像质量。

Purpose:To explore the feasibility of clinical application of low dose CT perfusion(CTP)imaging in peripheral arterial occlusive disease(PAOD)of lower extremities.Methods:Ninety patients with clinically diagnosed PAOD were randomly divided into three groups according to different tube voltages and tube currents:group A(120kV,lOOmAs),group B(80kV,1OOmAs)and group C(80kV,120mAs).Iterative reconstruction noise reduction technique was used in all patients.One-way ANOVA was used to compare the differences of image quality,perfusion parameters and radiation dose among the three groups.Results:Seventy-six patients with 148 lower limbs were included in the study.There was no statistical significant difference in clinical data among the three groups(P>0.05).There was statistical significant difference in objective image quality indexes among the three groups(P<0.05).The SNR,CNR and subjective quality scores of group A and group C were better than those of group B,and there was statistical significant difference between group A,group C and group B(P<0.001).There was no statistical significant difference in perfusion parameters among the three groups(P>0.05).The difference of radiation dose among three groups was with statistical significant(P<0.05),the dose of group C was reduced by 49%when compared with group A.Conclusions:It is feasible to use 80kV and 120mAs for low dose CTP examination of lower extremity in PAOD patients,which can significantly reduce radiation dose without affecting perfusion parameters and ensure image quality.