摘要目的 探讨灰阶实时超声造影(CEUS)和多排螺旋CT(MDCT)增强扫描兔肝VX2肿瘤的增强显像特征及兔肝超声造影时相的划分标准.方法 运用超声造影剂SonoVue对33只荷肝VX2瘤兔行CEUS和64排螺旋CT增强扫描,以团注造影剂后肝动脉开始增强作为动脉期的起始时间,以VX2肿瘤增强达峰时间作为门脉期的起始时间,以肝实质增强达峰值强度时间作为实质期的起始时间,观察其增强特征,比较CEUS中肿瘤和瘤周同水平肝实质的时间强度曲线和MDCT中腹主动脉、门静脉、肝实质和肿瘤的时间密度曲线形态特征,制定划分各期时相的标准.结果 CEUS和MDCT对VX2肿瘤动脉期、门脉期、实质期起始时间的划定分别为(6.82±1.36)s、(11.64±2.03)s、(20.24±4.17)s和(9.43±2.23)s、(13.77±2.01)s、(22.71±4.58)s,CEUS较MDCT各相起始时间均提早(P<0.01),二者对兔肝VX2肿瘤增强显像特征一致,均表现为"快进快退".结论 CEUS可以对兔肝VX2肿瘤的灌注情况进行实时高分辨率显像,CEUS和MDCT时相标准可为相关的影像学评估研究提供基本的理论依据.

abstractsObjective To investigate the imaging characteristics of rabbit liver VX2 tumor with contrast-enhanced ultrasonography(CEUS) and multidetector spiral CT(MDCT), to explore the criterion of phase timing apllicable to the model.Methods CEUS and MDCT were acquired in thirty-three New Zealand rabbits with hepatic VX2 tumors.The initial time of hepatic arterial phase was verified as the time the hepatic artery beginning to enhance,the initial time of portal phase as the time the VX2 tumor reaching peak enhancement and the initial time of hepatic parenchymal phase as the time the hepatic parenchyma reaching peak enhancement.The enhancing characteristics were observed.The time-intensity curve of VX2 tumor and peripheral parenchyma in CEUS was analysed and compared with the time-desity curve of abdominal aorta, portal vein, hepatic parenchyma and tumor in MDCT.Results The initial time of heptic arterial phase,portal phase and parenchymal phase in CEUS and MDCT was (6.82±1.36)s and (9.43±2.23)s,(11.64±2.03)s and (13.77±2.01)s,(20.24±4.17)s and (22.71± 4.58)s,respectively.The initial time of each phase in CEUS was earlier than that in MDCT (P<0.01).The contrast enhancing characteristics in CEUS and MDCT were consistent as fast wash-in and fast wash-out.Conclusions The status of hemodynamic perfusion in rabbit hepatic VX2 tumor could be well displayed by CEUS and the phase timing criterion concluded in this experimental study could offer fundmental theory basis for relevant imaging evaluation.