化学位移成像数字减影图诊断肝脂肪变性的价值  

The contribution of chemical shift imaging with digital subtracting images to the diagnosis of steatohepatitis

作　　者：郭兴华 刘启旺[2] 王娟萍 张崇杰 郑国芳 樊锐强 朱素梅 

机构地区：[1]山西省运城市中心医院医学影像科,044000 [2]山西医科大学第一医院放射科

出　　处：《中华放射学杂志》2006年第11期1178-1180,共3页Chinese Journal of Radiology

摘　　要：目的探讨化学位移成像数字减影图诊断脂肪肝的价值。方法对34例脂肪肝MRI资料,用化学位移成像的同相位图与反相位图进行减影,在减影图上测量并计算肝脾对比信号比(CNR),以此推断肝脏脂肪浸润,并将脂肪肝CT分度结果与这种减影法的CNR做Spearman相关分析,以观察CNR数值变化与脂肪肝严重程度的相关趋势;对52例正常肝脏和34例脂肪肝的MR图像,分别用直接目测法和减影法观察,以CT诊断为相对标准,用非配对资料卡方检验比较2种方法的敏感度与特异度。结果(1)在减影图上,52例正常者,肝脏、脾脏、肾脏等实质性器官表现为明显低信号,椎体松质骨、腹腔内脂肪、皮下脂肪层表现为高信号,肝、脾信号几乎相等,平均CNR为0.98±0.06;34例脂肪肝表现为肝内不同程度的散在的点状高信号,肝脏信号明显高于脾脏,CNR为3.25±0.91～14.35±6.10。(2)34例脂肪肝的CNR测量值与CT分度高度正相关(r=0.893,P<0.01)。(3)减影方法诊断脂肪肝的敏感度为88.24%,特异度为94.23%,高于直接目测法的32.35%和80.77%,差异具有统计学意义(P值分别<0.01、<0.05)。结论用化学位移成像数字减影图诊断脂肪肝敏感度、特异度较高,客观易行,且具有定量诊断的潜在能力。Objective To investigate the diagnosis value of chemical shift imaging with digital subtracting in steatohepatitis. Methods The in-phase images were subtracted by the out-phase ones in 34 cases of steatohepatitis, and the CNR were measured on these subtracted images to estimate the steatosis of the liver. The relationship of CT grade of steatohepatitis and CNR from the subtracted images was analyzed to evaluate the relationship between CNR and the degree of hepatic steatosis. The sensitivity and specificity of the subtracting and eyeballing methods were compared with chi-square test. Results On the subtracted images, the liver and spleen were seen nearly the same aspects as low signals , CNR = 0. 98 ± 0. 06, meanwhile the spongy vertebra and the subcutaneous or abdominal lipid were seen as obvious higher signals in 52 normal cases. On the 34 steatohepatitis, scattered high signals were seen in the liver, which made the signal of liver higher than that of spleen, CNR =3.25 ±0.91-14. 35 ±6. 10. There was positive correlation between CNR and CT grade in the 34 cases of steatohepatitis, r=0.893, P〈0.01. The sensitivity and specificity of the subtracting method were 88.24% and 94.23%, significantly higher than that of the eyeballing results. 32.35% and 80.77%, P〈0.01 and P〈0.05. Conclusion Chemical shift imaging with digital subtracting is a sensitive, specific, objective method to diagnose steatohepatitis and it is of potential ability for quantitative diagnosis.

关 键 词：脂肪肝 磁共振成像 减影技术 

分 类 号：R575.5[医药卫生—消化系统]