肝段MRI异常信号对肝脓肿诊断的价值

目的 分析肝脓肿的MRI表现，特别是肝段MRI异常信号，探讨其在肝脓肿诊断中的价值。资料与方法 对经临床或手术病理证实的24例肝脓肿的41个病灶的MRI资料进行回顾性分析。结果2 4例肝脓肿，单发13例，其中单房7例，多房6例；多发脓肿11例。肝段性异常信号灶29个，均表现为T2WI高信号，其中4个病灶T1WI呈低信号，其余T1WI无异常信号；22个表现为楔形，7个为圆形，范围、大小不一。8例行增强MRI者中，5例平扫表现肝段性异常信号的病灶均呈肝段性强化。另有2例MRI平扫呈肝段性T2WI高信号灶，CT增强检查见动脉期一过性肝段性强化。无论MRI增强还是CT增强其强化形态和范围与平扫MRI肝段性异常信号一致。结论 肝段MRI异常信号是炎症导致门静脉分支狭窄、血流减少，肝动脉血流代偿性增加所致，对肝脓肿诊断有重要价值。

The Value of Abnormal Hepatic Segmental Signal of MRI in Diagnosis of Liver Abscess

Objective To analyze the MRI appearance of liver abscess, especially abnormal hepatic segmental signal, and investigates diagnostic value of abnormal hepatic segmental signal of MRI in liver abscess. Materials and Methods The MRI data of 41 lesions in 24 cases with liver abscess proved by clinical or pathological was analyzed retrospectively. Results Of 24 cases, 13 cases were single lesion, including 7 solitary and 6 multiocular,11 cases were multiple lesions. 29 lesions was abnormal hepatic segmental signal with hyperintensity in T2WI and 4 lesions with hypointensity in T1WI and the other was normal in T1WI. 22 lesions were wedge shaped, 7 were round shaped, with the scope and size differently. Among 8 cases of MRI enhancement, 5 cases which showed abnormal hepatic segmental signal on plain scan were hepatic segmental enhancement, and other 2 lesions were transient hepatic segmental on CT enhancement which showed hepatic segmental hyperintensity in T2WI on plain MR scan. The enhanced shape and size on either MRI or CT was same to abnormal hepatic segmental signal in plain scan of MRI. Conclusion Abnormal hepatic segmental signal of MRI, as a consequence of stenosis of portal vein branch, decrease of blood flow, and compensatory increase of hepatic artery flow, it have the important value for diagnosis of liver abscess.