弥散加权成像评价直肠癌淋巴结转移的价值

目的：探讨MR弥散加权成像诊断直肠癌淋巴结转移的价值。方法：62例经病理证实直肠癌患者行MRI常规序列扫描及DWI，测量淋巴结ADC值，根据病理结果将MRI检出的淋巴结分为转移性和良性淋巴结两组，将盆腔淋巴结MRI诊断结果与手术病理结果相对照，比较两组淋巴结的ADC值差异是否有统计学意义。结果：共测量225个淋巴结ADC值，b值为800s／mm2，转移性淋巴结组平均ADC值为（0．76±0．15）×10^-3mm2／s，良性淋巴结组平均ADC值为（1．16±0．14）×10^-3mm2／s，两组平均ADC值差异有统计学意义（P〈0．05）。ADC值以1．0×10×10^-3mm2／s为阈值，判断转移性淋巴结与良性淋巴结时，灵敏度、特异度及准确度分别为：94．53％、91．62％和93．45％。结论：弥散加权成像诊断直肠癌淋巴结转移具有较大临床价值。

The Value of Diffusion-weighted Imaging in Diagnosing the Metastatic Lymph Nodes of Rectal Carcinoma

Objective： To investigate the value of diffusion-weighted imaging in diagnosing the metastatic lymph nodes of rectal carcinoma. Methods： 62 cases with rectal carcinoma confLrmed by pathology undertake MRI common sequence and DWI scanning, the apparent diffusion of coefficients （ADC） value of 225 lymph nodes were measured. Dive the lymph nodes to metastatic lymph nodes and benign lymph nodes by the pathology. The ADC of them were compared. Results： b = 800 s/mm2, the mean ADC value of metastatic lymph nodes and benign lymph nodes is （0.76 ±0.15）×10^-3mm2/s and （1.16 ±0.14）×10^-3mm2/s. There were significant differences between these ADC values （P 〈 0.05）. To distinguish metastatic lymph nodes and benign lymph with the threshold of ADC value is 1.0 ×10^-3mm2/s, the sensitivity is 94.53%, specificity is 91.62%, and accuracy is 93.45%. Conclusion： DWI posses comparatively great value in diagnosing the metastatic lymph nodes of rectal carcinoma.