Objective To access the value of MRI in differential diagnosis between intrahepatic cholangiocarcinoma and atypical hepatic abscess. Methods Retrospectively collecting and analyzing the clinical and MRI imaging data of 19 patients with intrahepatic cholangiocarcinoma (ICC) and 17 patients with atypical hepatic abscess, confirmed by reexamination after anti‐inflammation therapy, surgery or puncture etiology, from June 2011 to July 2018 in Central Hospital of Lishui City.They were divided into ICC and abscess groups.All patients underwent routine liver plain MRI, DWI and contrast‐enhanced MR scan. The MRI features of the two groups (including morphology, boundary, cystic change and necrosis, pseudocapsule, hemorrhage, lipid composition, the signature of lesion in different phases of MRI and surrounding tissue) were studied. Fisher exact test and t test were used. Result This study showed that there was statistical difference between the two groups in the following aspects, the presence of cystic degeneration, the degree of annular enhancement in arterial phase, the homogeneous enhancement in portal venous phase and balanced phase and the central filling enhancement sign (P<0.05).The results showed that necrotic cystic lesion was more common in the abscess group (15/17 cases) than in the ICC group (0/19 cases);in the cases with annular enhancement in arterial phase,the degree of enhancement in the ICC group (13/16 cases) was higher than that in the abscess group (2/9 cases); the enhancement of the central parenchyma of lesion on out‐of‐phase images (1/19 cases) was slower in the ICC group than that in the abscess group (14/17 cases);and the ICC group was likely to present as central filling enhancement compared to the abscess group. Conclusion The presence of cystic lesions in DWI, the enhancement degree of marginal parenchyma, the enhancement speed of central parenchyma and the whole enhancement pattern are essential signs for differentiating intrahepatic cholangiocarcinoma and atypical hepatic abscess. 图1 女,53岁,右肝脓肿.病灶最大径4.0 cm,病灶中的小囊变区在DWI上呈高信号(↑) 图2 女,39岁,右肝脓肿.病灶最大径3.1 cm,病灶中的小囊变区在DWI上呈高信号(↑) 图3 女,66岁,右肝肝内胆管细胞癌(ICC).病灶最大径5.3 cm,横轴面T2WI病灶整体呈不均匀高信号,内见相对更高信号的富黏液区(↑) 图4 男,45岁,右肝ICC.病灶最大径5.8 cm,横轴面T2WI病灶整体呈高低混杂信号,内见散在片状低信号的凝固性坏死区(↑) 图5 与图1为同一患者.横轴面T2WI病灶实质部分呈均匀高信号,小囊变区呈明显高信号(↑) 图6 与图2为同一患者.横轴面T2WI病灶实质部分呈等信号,小囊变区呈明显高信号(↑)图7 与图3为同一患者.增强扫描动脉期横轴面示病灶边缘轻度不规则环形强化 图8 与图4为同一患者.增强扫描动脉期横轴面示病灶强化环有多处中断征象(↑) 图9,10 男,45岁,右肝ICC.病灶最大径5.8 cm,增强扫描动脉期横轴面(图9)示病灶边缘局部显著环形强化,局部强化环明显中断(↑).平衡期横轴面像(图10)示病灶中央有填充强化 图11 与图3,7为同一患者.平衡期横轴面示病灶内富黏液区出现轻微中央填充强化(↑) 图12 与图4、8为同一患者.平衡期横轴面像示病灶中央有填充强化 图13,14 男,59岁,右肝脓肿.病灶最大径4.3 cm,动脉期横轴面像(图13)示脓壁散在强化,周围见片状异常灌注.平衡期横轴面像(图14)示脓壁均匀强化,其内囊变区无强化 图15 与图2,6为同一患者.平衡期横轴面像示脓壁均匀强化呈相对等信号,其内囊变区无强化(↑) 图16 与图1,5为同一患者.平衡期横轴面像示脓壁均匀强化呈相对等信号,其内囊变区无强化(↑)