1.5T磁共振扩散加权成像在胃癌淋巴结转移诊断中的应用价值

1.5T magnetic resonance diffusion weighted imaging in the diagnosis of lymph node metastasis of gastric cancer

目的:探讨1.5T磁共振扩散加权成像(DWI)在胃癌淋巴结转移诊断中的应用价值。方法:选择行1.5T磁共振腹部检查的95例胃癌患者,所有患者均给予常规序列及DWI序列扫描,以术后病理或临床随访为"金标准",观察转移淋巴结与非转移淋巴结MR表现,并绘制受试者工作特征曲线(ROC)比较淋巴结长径、短径及ADC值诊断效能。结果:①95例患者共检出肿大淋巴结146枚,转移性与非转移性淋巴结分别为81枚、65枚。在MR信号是否均匀及是否成簇分布方面,转移性淋巴结与非转移性淋巴结比较,差异均无统计学意义(P>0.05);②转移淋巴结长径、短径均大于非转移淋巴结,但差异无统计学意义(P>0.05),转移淋巴结ADC值小于非转移淋巴结,差异有统计学意义(P<0.05);③ROC曲线分析:长径、短径、ADC值曲线下面积分别为0.514、0.505、0.866,阈值分别为1.915 mm、1.200 mm、0.750×10~3mm^2/s;ADC值敏感度、特异度分别为82.9%、71.1%,显著高于长径(56.1%、47.4%)及短径(61.0%、53.3%)。结论:1.5T磁共振DWI序列在胃癌淋巴结转移诊断中具有较高敏感度及特异度。

Objective:To investigate the value of 1.5T magnetic resonance diffusion weighted imaging (DWI) in the diagnosis of lymph node metastasis of gastric cancer. Methods :95 patients with gastric cancer who underwent 1.5T magnetic resonance abdomen examination were studied, all patients were given routine sequence and DWI sequence scans. Follow-up pathological or clinical follow-up for the "gold standard" to observe the metastatic lymph nodes and non-metastatic lymph node MR performance, and draw the receiver operating characteristic curve (ROC) curve to compare lymph node long diameter, short diameter and ADC diagnostic efficiency. Results :A total of 146 enlarged lymph nodes were detected in 95 patients, 81 metastatic and 65 non-metastatic lymph nodes. In terms of MR signal uniformity and distribution, there was no significant difference between metastatic lymph nodes and non-metastatic lymph nodes ( P >0.05). The long and short diameters of the metastatic lymph nodes were larger than those of the non-metastatic lymph nodes, but the difference was not statistically significant ( P >0.05). The ADC value of the metastatic lymph nodes was smaller than that of the non-metastatic lymph nodes ( P <0.05). ROC curve analysis: the area under the long diameter, short diameter, and ADC values were 0.514, 0.505, and 0.866, and the thresholds were 1.915 mm and 1.200 mm, and 0.750×10 3 mm 2 /s;the sensitivity and specificity of ADC were 82.9%, 71.1%, significantly higher than long diameter (56.1%, 47.4%) and short diameter (61.0%, 53.3%). Conclusion: 1.5T magnetic resonance DWI sequence has high sensitivity and specificity in the diagnosis of lymph node metastasis of gastric cancer.