弹性比值法和评分法对甲状腺结节诊断价值的对比研究

Comparison of strain ratio and elastography score system in differential diagnosis of thyroid nodules

目的比较弹性比值法和评分法对甲状腺结节的诊断价值,从而为临床提供可靠的诊断方法。方法用超声弹性成像技术检查156个甲状腺结节,分别采用弹性比值法和弹性评分5分法对弹性图像进行评价,以甲状腺结节穿刺活检或术后病理做为对照。对两种方法的诊断作用做受试者工作特征曲线(ROC),分别得到曲线下面积和最佳分界点。采用χ2检验比较这两种方法的敏感性、特异性和准确性。P<0.05有统计学意义。结果根据ROC曲线,弹性比值法和评分法分别以3.855和4分为最佳分界点。弹性比值法的敏感性80.00%(40/50)、特异性90.57%(96/106)、准确性87.18%(136/156),弹性评分法的敏感性84.00%(42/50)、特异性78.30%(83/106)、准确性80.13%(125/156)。弹性比值法的特异性显著高于评分法(P<0.05)。结论弹性比值法对甲状腺结节的诊断价值较弹性评分法高,对甲状腺结节性质的判断更客观更可靠。

Objective To compare the diagnostic performance of strain ratio with that of the elastography score system in thyroid nodules in order to determine the relatively reliable diagnostic method. Methods 156 thyroid nodules were examined with freehand elastography and elastogram was evaluated by both five-degree elastography score system and thyroid tissue-to-nodule strain ratio before core biopsies or surgery which were used as standard reference.The area under the curve（AUC） and the best cut-off point were both obtained using receiver-operating characteristic（ROC） curve analysis.Sensitivity,specificity and accuracy were compared with χ2 test.P0.05 was considered to indicate significance. Results By applying the best cut-off points of 3.855 and 4 for stain ratio and elastography score system respectively,the sensitivity,specificity,accuracy for stain ratio were 80.00%（40/50）,90.57%（96/106）,87.18%（136/156）,respectively,while for elastography score system were 84.00%（42/50）,78.30%（83/106）,80.13%（125/156）.Strain ratio had significantly higher specificity（P0.05）,but lower sensitivity without significance（P0.05） than elastography score system. Conclusions Strain ratio was a more objective and reliable method than conventional elastography score system in differential diagnosis of thyroid nodules.