64层螺旋CT下肢动脉血管成像的注射速率与重建矩阵的选择

The optimal injection rate and reconstruction matrix study of CT arteriography for lower limb artery by 64-slice CT

目的探讨64层螺旋CT下肢动脉血管成像的最佳注射速率与重建矩阵的选择。方法将40例临床疑有下肢动脉疾病的患者随机等分为两组,采用Siemens Cardiac64层螺旋CT行CT血管成像检查。确定增强扫描范围、最佳注射速率与重建矩阵。对比剂注射速率一组为3.0ml/s,另一组为4.0ml/s。将获得的图像传入Wizard工作站进行MIP、VR、SSD、VE等后处理,比较两组原始图像及后处理图像质量。24例有DSA对照。每一病人做两次血管成像,一组一次全部成像,另一组为分三段成像。结果注射速率为4.0ml/s血管增强效果及重建图像质量要明显优于注射速率为3.0ml/s者。分段重建显示血管明显优于一次成像。结论正确的注射速率和重建方法选择是提高螺旋CT下肢动脉血管成像质量的关键。

Objective To investigate tremity artery angiography. Methods the optimal injection rate and reconstruction matrix in 64-slice spiral CT lower exForty patients with suspected peripheral arterial diseases underwent CT angiography （CTA） with Siemens Cardiac 64-slice spiral CT. The patients were divided into two groups randomly. The scan cover, injection rate and reconstruction matrix were assured. On one group contrast media was injected at a rate of 3.0 ml/s, and on the other group, the rate was 4.0 ml/s. Wizard workstation was used for further three-dimensional reconstruction, such as MIP, VR, SSD, VE, and compared the axial images with post-processing images. Conventional digital subtraction angiography （DSA） was performed as a standard reference in 24 patients. The images of patients which rate was 4.0 ml/s were reconstructed twice. On one group all images were loaded in the workstation, and the other group the images were divides into three subgroups, then were loaded in the workstation in turn for reconstruction. Results The lower limb arterial enhancement effect and the quality of reconstruction images were better in the group which using injection rate 4.0 ml/s than the group of 3. 0 ml/s. The CTA image quality of the group whose axial images were divided into three subgroups for reconstruction was clearer than the other. Conclusion The optimized injection rate and reconstruction matrix parameters of lower limb CT angiography could improve image quality.