磁共振胰胆管成像及其原始图像与磁共振常规扫描

·论著·

磁共振胰胆管成像及其原始图像与磁共振常规扫描

诊断胆总管结石的对照研究

赵天平,张勇,杜红,张伟

[摘要]目的对比磁共振胰胆管成像(MRCP)及其原始图像与磁共振常规扫描诊断胆总管结石的价值。方法应用1.0T超导MRI扫描仪对68例患者(48例单发或多发胆总管结石以及20例胆总管泥沙样结石)行MRCP扫描及常规轴

面FSE序列T

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WI扫描。结果MRCP的MIP图像能清晰显示肝内、外胆管及扩张胰管的形态结构。多数胆总管非泥沙

样结石在MRCP的M IP图像及MRI常规T

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WI图像均难以准确显示,而仅在MRCP原始图像上显示。MRI常规T2WI图像上,胆总管泥沙样结石均特征性地显示为胆总管内分层状改变,但其在MRCP的MIP图像上仅仅显示为局部信号模糊、减低或信号不均匀;在MRCP原始图像上仅在某一幅图像上显示为胆总管信号减低或信号不均匀。结论MRCP原始图像和MIP图像以及磁共振常规扫描是分析、诊断胆总管结石的一个有机整体,不能仅仅依靠某一种成像技术诊断胆总管结石。

[关键词]磁共振胰胆管成像;胆总管结石;对照研究

[中图分类号]R657.4;R445.2[文献标识码]A[文章编号]1681-2824(2006)07-0580-03 Comparison of magnetic resonance cholangiopancreatography and original im-ages with routine MRI in diagnosing common bile duct lithiasis

ZHAO Tian-ping,ZHANG Yong,DU Hong,et al.MR Room,Jiaozuo People s Hospital,Jiaozuo454002,China [Abstract]Objective To evaluate the value of magnetic resonance cholangiopancreatography(MRCP)and original images and routine MRI in diagnosing common bile duct lithiasis.Methods Sixty-eight patients(48

with common bile duct lithiasis and20with sandy lithiasis)underwent MRCP with routine axial MR T

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weighted fast spin echo sequences and heavy T2weighted imaging(T2WI)with fast spin echo sequences.Results Re-construction with maximum intensity projection(MIP)MRCP could definitely demonstrate the configuration of the bile duct and the enlarged pancreatic mon bile duct stones could not been demonstrated on MIP

and routine MRI T

2WI,but only been demonstrated on original images of MRCP.On routine MRI T

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WI,all of the

sandy stones characteristically showed delamination fashion,whereas MIP MRCP only demonstrated local faint signal intensity or asymmetric signal intensity,on original images of MR cholangiopancreatography,the sandy stones only demonstrated lower signal or asymmetric signal intensity.Conclusion MRCP and original images and routine MRI are an organic whole of diagnosing common bile duct lithiasis,none of which is reliable alone. [Key words]magnetic resonance cholangiopancreatography;common bile duct stones;comparative study

目前诊断胆总管结石的常用检查方法包括B超、螺旋CT、内镜逆行胰胆管造影(ERCP)等。B超检查对胆总管结石的诊断价值有限;CT检查则难以诊断等密度或低密度结石。磁共振胰胆管成像(magnetic resonance cholangiopan-

creatography,MRCP)不需造影剂即能较好地反映胆胰系统解剖关系和病理变化,获得不亚于ERCP的胆胰管显影图像,有三维成像、无创性、安全简便、诊断准确率高等优点,具有重要的临床应用价值[1,2]。本研究于2004年7月～2006年5月对68例胆总管结石患者进行MRCP成像及MRI常规轴面T

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WI扫描,并对照研究MRCP及其原始图像和MRI常规轴面扫描诊断胆总管结石的价值。

1资料与方法

1.1一般资料68例患者均同时行MRCP检查及磁共振

常规T

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WI扫描,男37例,女31例,年龄17～78岁,平均55岁。单发或多发胆总管结石48例,胆总管泥沙样结石20作者单位:454002河南焦作,焦作市人民医院磁共振室例,所有病例均经手术、病理证实。

1.2方法所有病例均使用GE Signa1.0T超导M RI扫描机。检查前禁食禁水4h以上,躯体正交表面线圈,仰卧位扫描,加用呼吸门控。常规行横轴面快速自旋回波(FSE)序列T2WI和自旋回波(SE)序列T1WI。MRCP扫描采用重T

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加权多次激发FSE序列。由横轴面T

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WI定位确定MRCP的扫描范围。磁共振常规扫描的序列参数:扫描范围上界包含肝顶,下界包含胰头全部;TR6000～8000ms,TE80～100ms;层厚5～8mm,层间距2mm,FOV 36mm×27mm,矩阵320×256,接收器带宽20.8,回波链长度16,激励次数(NEX)为4次,扫描时间220s。冠状面FSE序列连续多层面重T2加权扫描采用不屏气呼吸触发(respiratory triggering)技术减少呼吸运动伪影。使用短TI 反转恢复(STIR)序列获得脂肪组织信号背景抑制效果。

重T

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加权多次激发FSE序列,扫描参数:TR取无穷大值, TE160～250ms,FOV38～42cm,矩阵256×192,层厚3.0mm,层间隔0mm,接收器带宽31.25,回波链长度25,激