两种支气管内超声弹性成像定量方法评估胸内良恶性淋巴结的比较

Comparison of two quantitative methods of endobronchial ultrasound real-time elastography for evaluating intrathoracic lymph nodes

目的比较两种支气管内超声实时弹性成像（EBUS—RTE）定量方法评估胸内良恶性淋巴结的临床价值。方法选择2014年1—4月在上海市胸科医院接受EBUS-TBNA检查的患者，同时进行EBUS．RTE操作。每一处淋巴结均有一张选定的代表性EBUS—RTE图像，使用硬区域比率法和H分量均值法分析兴趣区。以EBUS—TBNA病理和微生物检测结果，及其他病理、微生物检测结果和临床随访确定病变性质，评估两种定量方法的敏感度、特异度、阳性预测值、阴性预测值及准确率。结果共入组56例患者，68处淋巴结，其中35处恶性淋巴结，33处良性淋巴结。硬区域比率法和H分量均值法定量分析EBUS—RTE图像时，良恶性病变的数值分别为0．32±0．29、0．62±0．20和109．99±28．13、141．62±17．52，两者比较差异均有统计学意义（t=-5．14，P〈0．01；t=-5．53，P〈0．01）。硬区域比率法、H分量均值法的受试者工作曲线下面积分别为0．813、0．814。硬区域比率法、H分量均值法的临界值分别为0．48、126．28时，敏感度、特异度、阳性预测值、阴性预测值和准确率分别为82．86％、81．82％、82．86％、81．82％、82．35％及85．71％、75．76％、78．95％、83．33％、80．88％。结论硬区域比率法和H分量均值法均可用于EBUS—RTE图像的定量分析，具有鉴别胸内淋巴结良恶性的价值，硬区域比率法更佳。

Objective To compare the clinical value of two quantitative methods in analyzing endobronchial ultrasound real-time elastography （EBUS-RTE） images for evaluating intrathoracic lymph nodes. Methods From January 2014 to April 2014, EBUS-RTE examination was performed in patients who received EBUS-TBNA examination in Shanghai Chest Hospital. Each intrathoracic lymph node had a selected EBUS-RTE image. Stiff area ratio and mean hue value of region of interest （ ROI ） in each image were calculated respectively. The final diagnosis of lymph node was based on the pathotogic/microbiologic results of EBUS-TBNA, pathologic/microbiologic results of other examinations and clinical following-up. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were evaluated for distinguishing malignant and benign lesions. Results Fifty-six patients and 68 lymph nodes were enrolled in this study, of which 35 lymph nodes were malignant and 33 lymph nodes were benign. The stiff area ratio and mean hue value of benign and malignant lesions were 0. 32 ± 0. 29, 0. 62 ± 0. 20 and 109. 99 ± 28.13, 141.62± 17.52, respectively, and statistical differences were found in both of those two methods （t = -5. 14,P 〈 0.01; t = -5.53,P 〈 0. 01 ）. The area under curves was 0. 813, 0. 814 in stiff area ratio and mean hue value, respectively. The optimal diagnostic cut-off value of stiff area ratio was 0. 48, and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 82. 86%, 81.82% , 82. 86%, 81.82% and 82. 35% , respectively. The optimal diagnostic cut-off value of mean hue value was 126. 28, and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 85.71%, 75.76%, 78.95%, 83.33% and 80. 88%, respectively. Conclusion Both the stiff area ratio and mean hue value methods can be used for analyzing EBUS-RTE images quantitatively, having the value of differentiating benign and malignant intrathoracic lymph nodes, and the stiff area ratio is better than the mean hue value between the two methods.