可变螺距技术在颈动脉、冠脉CTA一站式扫描中的应用  

Value of VHP technology in one-stop CTA of carotid and coronary arteries

作　　者：邢俊 贾一鸣 焦静[1] 倪其鸣 孙炎冰 于红 XING Jun;JIA Yiming;JIAO Jing;NI Qiming;SUN Yanbin;YU Hong(Department of Imaging,Chest Hospital Affiliated to Shanghai Jiao Tong University,Shanghai 200120,China)

机构地区：[1]上海交通大学附属胸科医院放射科,上海200030 [2]同济大学附属东方医院放射科,上海200120

出　　处：《影像诊断与介入放射学》2023年第5期336-341,共6页Diagnostic Imaging & Interventional Radiology

基　　金：国家自然科学面上基金(8207070786、81871353);国家自然科学青年基金(82302188);上海市浦江计划(22PJD069);上海市卫生健康青年人才基金(2022YQ060);上海市科委医学创新项目(22Y11911100)。

摘　　要：目的探讨320排CT在颈动脉CTA和冠脉CTA检查中使用可变螺距(VHP)法一站式扫描与常规方法扫描相比,图像质量和辐射剂量上的差异。方法收集我院怀疑颈动脉疾病、冠心病行颈动脉、冠脉CTA检查患者50例,随机分成A、B两组。A组使用VHP法,从心脏往头侧扫描,先经心脏处开启心电监护模式,至气管分叉处后自动切换大螺距扫描(Fast)。B组患者分两天行常规冠脉CTA容积扫描及颈动脉螺旋扫描。测量两组图像主动脉根部、冠脉开口(右冠)、颈动脉(包括颈动脉开口、颈动脉分叉)、基底动脉及颈静脉层面的CT值。由两名有经验的放射科医生评价图像质量并进行统计学分析,同时比较两组图像质量、对比剂用量及辐射剂量。结果A、B两组颈静脉的信噪比(SNR)、对比噪声比(CNR)、CT值、标准差(SD)值分别为9.92±2.84、8.08±2.85、(247.63±63.58)HU、25.58±5.13及4.42±1.19、1.84±1.04、(77.70±17.74)HU、18.73±2.89,两组间差异均有统计学意义(P<0.001)。A、B两组其余图像质量客观评价及主观评价均无统计学差异(P>0.05)。在患者辐射剂量、对比剂用量上,A组[(992.94±177.43)mGy·cm、(60.06±11.22)mL]相较于B组[(1077.35±117.36)mGy·cm、(100.50±9.79)mL]降低了7.8%和40.2%,差异有统计学意义(P<0.001)。结论VHP技术下的颈动脉、冠脉CTA一站式扫描可在不影响诊断且确保图像质量的基础上一次完成检查,减少对比剂用量及辐射剂量。Objective To investigate the difference in image quality and radiation dose between 320-slice CT with variable helical pitch(VHP)one-stop scanning and conventional scanning in carotid and coronary CT angiography(CTA).Methods 50 patients with suspected carotid artery disease and coronary heart disease were randomly divided into A and B groups.Group A was scanned from heart to head using the VHP method.The electrocardiogram monitoring mode was started at the heart and then the fast thread scanning was automatically switched to the trachea bifurcation.Patients in group B underwent routine coronary CTA volume scanning and carotid spiral scanning on two separate days.The CT values of aortic root,right coronary artery opening,carotid artery opening and bifurcation,basilar artery,and jugular vein were measured.The image quality was evaluated by two experienced radiologists.The image quality,contrast agent dosage and radiation dose of the two groups were compared.Results The signal-to-noise ratio(SNR,9.92±2.84),contrast-to-noise ratio(CNR,8.08±2.85),CT values(247.63±63.58)HU,and standard deviation(SD,25.58±5.13)of the jugular vein in group A were significantly higher(P<0.001)than that of group B[4.42±1.19,1.84±1.04,(77.70±17.74)HU,18.73±2.89].The subjective carotid artery score of group B(3.65±0.49)was 33.7%higher than that of group A(2.73±0.45)and there was no significant difference in qualitative evaluation between the two groups(P>0.05).Radiation dose(992.94±177.43)mGy·cm and contrast agent dosage(60.06±11.22)mL in group A were significantly(P<0.001)and respectively reduced by 7.8%and 40.2%compared to that in group B[(1077.35±117.36)mGy·cm,(100.50±9.79)mL].Conclusion The one-stop scanning of carotid and coronary artery CTA using VHP technology improves image quality and reduces the dosage of contrast agent and radiation exposure.

关 键 词：可变螺距 低剂量 低对比剂 联合扫描 

分 类 号：R814.42[医药卫生—影像医学与核医学] R543.3[医药卫生—放射医学] R543.4[医药卫生—临床医学]