一过性肝段性强化在肝脓肿动态增强CT诊断中的价值

目的分析肝脓肿的动态增强U表现，特别是肝段性强化，并复习文献探讨其产生的病理基础。资料与方法回顾分析经临床或病理证实的11例24个肝脓肿的动态增强CT表现，所有病例均进行了肝动脉期、门静脉期和实质期的肝脏3期动态增强CT检查。结果24个肝脓肿中，20个位于肝右叶，4个位于左叶。典型肝脓肿4个，表现为双靶征、中心均匀低密度，内含气体；不典型肝脓肿20个，其中16个表现为蜂窝状，并有持续强化征、边缘锐利征等，其余4个非蜂窝状表现，但有段性强化。24个肝脓肿有18个出现段性强化，发生率为75％。结论段性强化是肝脓肿的又一重要的动态增强CT表现，在肝脓肿的诊断中有重要价值。其病理基础是炎症导致门静脉血流量减少．而引起肝动脉的流量增加所致。

The Value of Transient Hepatic Segmental Enhancement during Dynamic Enhanced CT Scanning in the Diagnosis of Hepatic Abscess

Objective To analyze dynamic enhanced CT findings, especially transient hepatic segmental enhancement, in hepatic abscess, to review the related literatures and to discuss its pathologic basis.Materials and Methods Triphasic, including arterial, portal and parenchymal phase, dynamic contrast enhanced CT findings in 11 patients with 24 clinically or pathologically proved hepatic abscesses were retrospectively analyzed, focusing on the transient hepatic segmental enhancement.Results Of the 24 lesions, 20 were located in the right lobe, and 4 in the left lobe. Typical imaging signs were seen in 4 lesions, presenting as double target sign, air contained homogeneous low density in lesion's center. Twenty lesions were atypical, showing signs of honeycomb appearance with lasting enhancement, sharp border or spider feet sign (n=16), or displaying transient hepatic segmental enhancement without honeycomb appearance (n=4). Transient hepatic segmental enhancement occurred in 18 of 24 lesions (75%). Conclusion Transient hepatic segmental enhancement is another valuable dynamic enhanced CT sign for the diagnosis of hepatic abscess. It may be caused by the increased hepatic arterial flow due to the reduction of the portal blood flow which is resulted from inflammation of the portal tracts.