多层螺旋CT肝脏双期血管成像及临床应用

Multislice Helical CT Dual-phase Angiography of the Liver and Its Clinical Applications

目的 探讨多层螺旋CT(MSCT)肝脏多期扫描 ,肝动脉和门静脉双期血管成像的可能性及其临床应用。资料与方法 14例正常者及 15例肝硬化患者 (包括 6例肝癌 )行MSCT多期扫描 ,准直 2 .5mm ,pitch 5 ,每期扫描时间约为 6～ 9s。分别于肝动脉期和门静脉期进行血管三维成像 ,重建方式为容积再现技术 (VR) ,最大密度投影(MIP) ,表面遮盖法重建技术 (SSD)。统计 3种成像方法对胃十二指肠上动脉 ,肝固有动脉 ,肝左、右动脉的显示率 ,并对门静脉显示情况进行评分。结果 肝动脉期血管成像可清晰显示扫描范围内的腹主动脉 ,腹腔干血管及其分支 ,VR、MIP及SSD对胃十二指肠动脉 ,肝固有动脉 ,肝左、右动脉的总显示率分别为 85 .3% ,85 .3% ,6 6 .4 %。门静脉期血管成像能清晰显示门静脉系统情况 ,正常人门静脉可显示 6级以上 ,VR及MIP优于SSD(P <0 .0 5 ) ,VR立体感强于MIP。结论 MSCT肝脏多期扫描 ,双期血管成像是了解肝脏供血动脉和门静脉系统情况的无创性检查方法 ,以VR血管成像最佳 。

Objective To discuss the feasibility of dual phase angiography of the liver with multislice helical CT and to assess its clinical applications. Materials and Methods Multislice helical CT scanning, with the collimation of 2.5 mm, pitch of 5 and scanning time of 6～9s for each phase, was performed in 14 healthy subjects and in 15 cirrhosis patients (6 of which suffered from hepatic cancers). Both arterial and portal phase 3D vascular imaging, using volume rendering (VR), SSD and MIP techniques, was conducted. The displaying rate of superior gastroduodenal artery, proper hepatic artery and its right and left branches with three imaging techniques was calculated respectively. The visualization quality of the portal vein was evaluated.Results During hepatic arterial phase, the abdominal aorta, the celiac artery and its branches were well shown. The total displaying rate of the superior gastroduodenal artery, proper hepatic artery and its right and left branches for VR, MIP and SSD was 85.3%, 85.3% and 66.4%, respectively. During portal vein phase, the portal system was clearly demonstrated, with VR and MIP being superior to SSD (P<0.05). VR had stronger three dimentional effect than MIP. Conclusion Multislice helical CT dual phase angiography of the liver is a non invasive technique for observing hepatic arteries and portal system, providing useful information for the clinicians. VR is superior to MIP and SSD in producing best 3D images.