多层螺旋CT及MRI对肝脏结核性肉芽肿的诊断价值

Tuberculous granuloma of the liver:diagnostic value of MSCT and MRI

目的:探讨MSCT及MRI对肝脏结核性肉芽肿的诊断价值。方法:回顾性分析7例经手术或穿刺病理证实的肝脏结核性肉芽肿的影像表现。其中男5例,女2例,均行上腹部MSCT和MRI平扫及动态增强扫描,MRI扫描序列包括FSPGR T1WI、FRFSE T2WIF、SPGR T1WI动态增强和DWI(b=500 s/mm2)扫描。结果:7例中表现为肝实质内单发结节6例,多个粟粒结节聚集成簇状1例。5例CT平扫呈稍低密度,2例呈等密度,3例病灶内有点状或粉末状钙化。MRI平扫4例呈T1WI低信号、T2WI高信号,3例病灶T2WI上表现为中心低信号、周边高信号。DWI示病灶呈稍高信号,ADC值平均为(1.379±0.297)×10-3mm2/s,相对ADC为1.263±0.148。增强扫描示4例动脉期轻度不均匀强化,门静脉期及延迟期强化程度逐渐增加,其中3例病灶周围肝组织出现一过性晕状强化;3例动脉期未见明显强化,门静脉期及延迟期示病灶边缘轻度环状强化。结论:MSCT及MRI对肝脏结核性肉芽肿具有较高诊断价值,在一定程度上能反映病变所处的病理时期。

Objective：To evaluate the application of MSCT and MRI in the diagnosis of tuberculous granuloma of the liver.Methods：The authors retrospectively evaluated the appearance of MSCT and MRI of 7 patients（5 males,2 females） with tuberculous granuloma of the liver confirmed by surgical and pathologic findings at our institution between January 2004 and October 2009.All of the patients underwent routine epigastric MSCT and MRI examinations.MR imaging sequence consisted of FSPGR T1WI,FRFSE T2WI,FSPGR T1WI dynamic contrast-enhanced MRI（DCE-MRI） and diffusion weighted imaging（DWI,b=500s/mm2）.Results：On radiological examinations,6 tuberculous granulomas were solitary,while 1 was multiple and clustered.5 lesions showed slightly low density and 2 lesions isodensity on plain CT scan images.Punctiform or powdery calcification was found in 3 lesions.Among the lesions,4 lesions were hypointense on T1WI and hyperintense on T2WI;3 lesions were hypointense in the central portions and hyperintense in the periphery on T2WI.All the lesions were slightly hyperintense on DWI（b=500s/mm2） and the mean ADC value was（1.379±0.297）×10-3mm2/s,the ratio of ADC was 1.263±0.148.On contrast enhancement CT and MRI,4 lesions showed slightly peripheral rim enhancement on arterial-phase images and conspicuously increased on portal-phase and delayed images.Perifocal transient enhancement was observed in 3 lesions which was thought to reflect inflammatory hyperemia.Three lesions were inconspicuous on arterial-phase images but showed slightly rim enhancement on portal-phase and delayed images.Conclusion：MSCT and MRI play an important role in diagnosing tuberculous granuloma of the liver and to some extent illustrate pathological period of the lesions.