不同造影剂注射方案对头颈部动脉CT血管造影扫描图像的影响

Optimization of the Scanning Technology on CT Angiography in Cervical and Cerebral Vascularity Imaging

【目的】探讨不同造影剂注射方案对头颈部动脉CT血管造影扫描图像质量的影响。【方法】随机选择本院收治的需要进行头颈部动脉造影的112例患者，将其分为观察组和对照组；每组各56例。观察组采用下肢团注造影剂方法，对照组采用上肢团注造影剂方法。原始数据采用容积再现、最大密度投影及多平面重组技术进行后处理，观察各部位血管CT值及血管显像质量，对比两组患者头颈部动脉血管显像质量，并采用主观评分3级评分法评估图像质量。【结果】观察组双侧颈总动脉CT值显著低于对照组，差异具有统计学意义（P〈0．05）；观察组双侧锁骨下动脉、颈总动脉起始部、头臂干血管显像评分优于对照组，差异具有统计学意义（P〈0．05）。【结论】在不增加造影剂和辐射剂量的前提下，通过下肢静脉团注造影剂，可取得较好血管显像质量，还能得到更多显像质量较好的血管信息，有利于及早发现相关部位的病变。

[Objective]To investigate the image quality of carotid and cerebrovascular computed tomography angiography （CTA） with the lower extremity veins contrast medium （CM） injection strategy compared with the conventional upper extremity veins contrast medium injection strategy. [Methods]One hundred and twelve patients （52 male, 60 females with mean age 26.34 ± 2.37 years） were randomly divided into two groups （with 56 patients in each group） and underwent carotid and cerebrovascular CTA with different CM injection strategies. Fifty-six patients （Group A） were scanned with a standard CTA protocol with the lower extremity veins CM injection strategy. Group B were scanned with the conventional upper extremity veins CM injection strategy. Other scan parameters remained the same with the two groups. To evaluate the image quality objectively, CT value were measured at eight selected regions. To evaluate subjective image quality, two readers evaluated the vessel visibility and artifact caused by the intravenous CM in common carotid artery and subclavian artery by using 3-point scale. [Results]There is no significant difference between objective image parameters of the two groups （ P〉0.05）. However, both the readers noticed a better image quality in Group A because of the intravenous CM artifact reduction. There is also a significant difference between the image score of Group A and Group B （ P〈0.01）. [Conclusion]The study indicates that the lower extremity vein CM injection method can greatly reduce the artifact caused by the intravenous CM as well as improve vessel visibility of the arteries near veins-especially for common carotid artery and subclavian artery.