磁共振信号强度与动脉早期强化模式诊断肝脏小结节病灶的价值分析  

Analysis of Signal Intensity and Enhancement Patterns of Early Arterial Phase of Small Hepatic Nodular Lesions on MRI

作　　者：邬颖华[1] 宋彬[1] 徐隽[2] 吴苾[1] 

机构地区：[1]四川大学华西医院放射科,成都610041 [2]四川省第四人民医院CT室,成都610016

出　　处：《中国普外基础与临床杂志》2009年第3期240-244,256,共6页Chinese Journal of Bases and Clinics In General Surgery

摘　　要：目的分析磁共振常规T2W、T1W平扫下病灶信号强度及相应的信噪比（SNR）、对噪比（CNR）结合病灶动脉早期强化模式在肝脏小结节病灶定性与鉴别诊断中的价值。方法收集了2007年5月至2008年3月期间来四川大学华西医院作腹部MRI检查的肝脏小结节病灶患者68例，其中男46例，女22例；年龄24-78岁，平均51岁。后经手术、病理、实验室检查、随访追踪及多种影像学综合检查确诊为小肝细胞癌28例（29个病灶），肝转移癌14例（33个病灶），肝血管瘤14例（22个病灶），肝囊肿12例（18个病灶），共计102个病灶。病灶直径2-30mm，平均（21．1±6．8）mm。所有病例相继进行常规T2W、T1W平扫和VIBE序列的钆剂多期增强（动脉早期、动脉晚期和门脉期）扫描。以临床、手术病理结果为标准，重点观察各组病灶在平扫T2W、T1W的信号强度及相应的SNR、CNR和多期增强扫描中动脉早期病灶的强化模式。结果MRI平扫T2W结节呈高信号者为100％，T1W呈低信号者为93．1％。T2W以肝囊肿的SNR、CNR值最高，其次为肝血管瘤、肝转移癌，最小为小肝细胞癌（P〈0．05）；T1W以小肝细胞癌的SNR值及肝囊肿的CNR值最高，与其他3种病灶的差异有统计学意义（P〈0．05）。动脉早期肝脏结节病灶的强化率占76．5％（78／102）；小肝细胞癌和肝转移癌的动脉早期强化率分别达100％（29／29）及87．9％（29／33），肝囊肿100％无强化；最常见的强化模式是边缘强化，达35．3％（36／102），均匀与不均匀强化模式分别为21．6％（22／102）及19．6％（20／102）。结论MR信号强度的定性与定量研究和动脉早期病灶强化模式的结合有助于肝脏小结节病灶的定性与鉴别诊断。Objective To retrospectively assess the importance and imaging appearance of the signal intensity, the signal noise ratio （SNR）, the contrast noise ratio （CNR） and enhancement patterns of early arterial phase in diagnosis and differential diagnosis of small hepatic nodular lesions on MRI. Methods Conventional spin-echo T2W, 2D GRE T1W plain scan and Gd-enhanced 3D-VIBE multi-phasic （early arterial, late arterial and portal venous phase） acquisitions were performed for 68 consecutive patients with 102 lesions on MRI. Native T2W and 2D GRE T1W were acquired first, then 3D-VIBE fast scanning at early arterial, late arterial and portal venous phase respectively. The SNR, CNR, signal intensity and enhanced pattern of the nodular lesions appearances on plain scan and early arterial phase were carefully observed. Results There were hyperintense in 102 （100%） lesions in T2W and hypointense in 95 （93. 1%） lesions in T1W in plain scan. There were differences among the SNR, CNR of hepatic cyst, cavernous hemangioma, neoplasm metastasis and small hepatocellular carcinoma in T2W （P〈0.05）, the highest SNR and CNR of lesions were hepatic cyst. The SNR of small hepatocellular carcinoma and the CNR of hepatic cyst were highest in all the type diseases in T1W, there was significantly difference as compared with the other type diseases （P〈0.05）. The enhancement rate of small hepatic nodular lesions was 76.5% in early arterial phase. The enhancement rate of small hepatocellular carcinoma and hepatic metastasis were 100% and 87.9% respectively. The non-enhancement rate of hepatic cyst were 100 %. The common enhancement patterns of early arterial phase were peripheral enhancement which were 36 lesions （35. 3%）. The even enhancement and uneven enhancement were 22 lesions （21.6 % ） and 20 lesions （19.6 % ） respectively. Conclusion Qualitative and quantitative evaluation of MR signal intensity combined with the enhancement patterns of early arterial phase will help for qualitation and different

关 键 词：磁共振成像 小肝细胞癌 信号强度 强化模式 

分 类 号：R657.3[医药卫生—外科学] R445.2[医药卫生—临床医学]