摘要目的 探讨MR弹性成像(MRE)评价正常胰腺、鉴别胰腺占位性病变的价值.方法 回顾性搜集经手术病理证实的62例胰腺病变患者(病变组),并招募健康志愿者20名(对照组).病变组62例中,实性肿瘤57例(恶性39例、良性18例),囊性肿瘤5例.所有受试者均行腹部低频(40 Hz)3.0 T MRE检查.测量胰腺肿瘤和正常胰腺组织的弹性值,并对两者采用Mann-Whitney U检验进行比较.采用ROC评价弹性值鉴别胰腺肿瘤的效能.结果 弹性图对病灶的总体检出率(敏感度)为91.9%(57/62),误诊率(假阳性率)5.0%(1/20),漏诊率(假阴性率)为8.1%(5/62).对照组和病变组的弹性值[中位数(上、下四分位数)]分别为1.18(1.15,1.30)和2.43(1.94,3.64)kPa,差异有统计学意义(Z值为-5.967,P<0.01).以弹性值≥1.36 kPa区分正常胰腺与胰腺肿块的ROC下面积为0.946,诊断敏感度和特异度分别为93.6%和100.0%;以弹性值≥2.17 kPa鉴别良、恶性实性占位性病变的敏感度和特异度分别为82.1%和83.3%.结论 MRE有助于区分正常胰腺及胰腺占位性病变,并对鉴别胰腺良、恶性病变有一定价值.

abstractsObjective To investigate the feasibility of spin-echo echo-planar imaging(SE-EPI) of magnetic resonance elastography (MRE) for the diagnosis of pancreatic mass and to evaluate the difference of stiffness value in different pancreatic mass. Methods In a retrospective study, MRE was performed in 20 healthy volunteer (control group) and 62 patients with surgery-proved pancreatic masses, including pancreatic cystadenoma in 5 cases and solid masses of pancreas in 57 cases (39 with malignant mass and 18 with benign mass) using 3.0 T MRE. The differences of stiffness between two groups were evaluated using non-parametric Mann-Whitney U test. ROC was used to assess the diagnostic ability of elastogram for the detection of pancreatic masses, and to evaluate MRE-determined stiffness for the differentiation of masses from healthy pancreas, and malignancy from benign solid masses. Results The total detection rate of elastogram was 91.9%(57/62),with false positive rate of 5.0%(1/20) and false negative rate of 8.1%(5/62). The median stiffness value in the control group vs patient group were 1.18 kPa (interquantile range:1.15 to 1.30) kPa and 2.43 kPa (interquantile range:1.94 to 3.64 kPa) respectively, with statistically significant differences (Z=-5.967,P<0.01). The sensitivity and specificity of stiffness (≥1.36 kPa) to differentiate pancreatic mass from healthy pancreas was 93.6%and 100.0%, respectively, and to differentiate benign and malignant solid masses (≥2.17 kPa) was 82.1%and 83.3%, respectively. Conclusion MRE is a promising method in detecting and distinguishing different pancreatic masses.