弹性成像评分法与应变率比值对甲状腺肿块鉴别诊断的对比研究

Value of strain ratio in differential diagnosis of thyroid tumors：compared with evaluation based on elastography scores

目的探讨超声弹性成像评分法与应变率比值（strain ratio，SR）在甲状腺肿块良、恶性鉴别诊断中的价值。方法对67例患者92个甲状腺肿块进行超声弹性成像检查，计算肿块与周围正常组织的SR值，并分别采用4分评分法及5分评分法对肿块进行评价。以手术病理诊断为金标准，比较三种方法对肿块鉴别诊断的能力。结果①构建ROC曲线获得三种方法的曲线下面积为0．885、0．904、0．961，SR值的曲线下面积明显大于两种评分法（Pd0．05）。②以3分为最佳截断点，4分及5分评分法对甲状腺恶性肿块诊断的敏感性、特异性和准确性分别为78．0％、86．3％、82．6％和80．5％、88．2％、84．8％。③以3．57为良、恶性肿块SR值的最佳截断点，其敏感性、特异性和准确性分别为92．7％、92．2％、92．4％，均高于两种评分法。结论SR值为甲状腺肿块的鉴别诊断提供了一种新的半定量手段。

Objective To investigate the clinical value of strain ratio in differential diagnosis of thyroid tumors, compared with the evaluation based on elastography scores. Methods Elastography examinations were performed in 67 patients with 92 thyroid tumors. Ultrasonic elastograms were evaluated according to the four- and five-score system respectively. Strain ratio of the tumor and the surrounding tissue was also calculated. Clinical value of the three evaluations was compared with pathological findings as the reference standard. Results The area under the curve..0. 885 for the four-score, 0. 904 for the five-score, 0. 961 for the strain ratio. When a cutoff point of 3 was used,four-score and five-score showed a sensitivity of 78.0% ,a specificity of 86.3% ,an accuracy of 82.6% and a sensitivity of 80.5% ,a specificity of 88.2%, an accuracy of 84.8 %, respectively. When a cutoff point of 3.57 was introduced, the strain ratio had 92.7 % sensitivity,92.2% specificity, 92.4% accuracy. Conclusions Strain ratio was more helpful in diagnostic performance of thyroid tumors as a new semi-quantitative method than elastography scores.