背景抑制扩散成像(DWIBS)对鉴别盆腔良恶性淋巴结的价值

目的背景信号抑制弥散加权成像(DWIBS)是一种高分辨的体部DWI技术。探讨DWIBS在盆腔淋巴结病变鉴别诊断中的价值。方法收集44例共99枚经手术病理证实的盆腔淋巴结病变,对其实质部分的ADC值进行测量,包括恶性转移瘤73枚,良性增生26枚。采用DWIBS序列扫描并比较盆腔良、恶性淋巴结实质ADC的值是否具有显著性差异。采用诊断试验的ROC曲线分析确定ADC值的诊断阈值。结果 DWIBS对盆腔淋巴结病变显示良好。良性淋巴结实质部分的ADC值为(1.36±0.84)×10~(-3)mm~2/s,恶性肿瘤转移淋巴结组为(0.97±0.19)×10~(-3)mm~2/s。两组平均值之间的差异具有统计学意义(P0.05)。当以ADC值等于1.23×10~(-3)mm~2/s作为鉴别良恶性的诊断指标,其诊断价值为优(Az值=0.963,P0.05),灵敏度为96.2%,特异度为93.2%。结论 DWIBS在盆腔淋巴结病变中具有良好的应用前景,ADC值可用于盆腔淋巴结良恶性病变的鉴别。

Use of diffuslon-weighted MR imaging with background signal suppression in differential diagnosis of benign or malignant pelvic lymph nodes

Objective Diffusion-weighted whole body magnetic resonance imaging with background body signal suppression （DWIBS） is a high-resolution diffusion-weighted imaging （DWI） technique. The objective of this study was to determine the value of DWIBS in differentiating benign or malignant lymph nodes in the pelvis. Methods DWIBS （b=0,1000 s/mm^2） of 99 histologically confirmed lymph nodes was analyzed. The apparent diffusion coefficients （ADCs） of 73 malignant and 26 benign nodes were compared. The cutoff ADC value between malignant and benign lesions was determined using ROC analysis. Results The mean ADC values of benign nodes （1.36±0.84×10^-3mm^2/s） were significantly （P〈 0.05） higher than those of malignant nodes （0.97±0.19×10^-3mm^2/s）. With the cutoff ADC value of 1.23×10×10^-3mm^2/s, the sensitivity and specificity for differentiating benign from malignant nodes were 96.2% and 93.2% respectively. The diagnostic value was very good （Az=0.963, P〈 0.05）. Conclusion DWIBS is useful for differentiating benign from malignant pelvic lymph nodes.