Diagnostic value of computed tomography (CT) histogram analysis in thyroid benign solitary coarse calcification nodules

Abstract

This study was to investigate the diagnostic value of the computed tomography (CT) histogram in thyroid benign solitary coarse calcification nodules (BSCNs). A total of 89 thyroid solitary coarse calcification nodules (coarse calcification ≥5 mm, no definite soft tissue around calcification) confirmed either by surgery or histopathological examination in 86 cases enrolled from January 2009 to December 2015 were evaluated. These included 56 BSCNs and 33 malignant solitary coarse calcification nodules (MSCNs). Overall, 27 cut-off values were calculated by N (4≤N≤30) times of 50 Hounsfield units (HU) in the range of 200 to 1500 HU, and each cut-off value and the differences in the corresponding area percentages in the CT histogram were recorded for BSCN and MSCN. The optimal cut-off value and the corresponding area percentage were established by receiver operating characteristic (ROC) curve analysis. In the 19 groups with an ROC area under curve (AUC) of more than 0.7, at a cut-off value of 800 HU and at an area percentage of no more than 93.8%, the ROC AUC reached the maximum of 0.79, and the accuracy, sensitivity, and specificity were 75.3%, 80.4%, and 66.7%, respectively. At a cut-off value of 1050 HU and at an area percentage of no more than 93.6%, the accuracy, sensitivity, and specificity were 71.9%, 60.7%, and 90.9%, respectively. At a cut-off of 1150 HU and area of no more than 98.4%, the accuracy, sensitivity, and specificity were 70.8%, 57.1%, and 93.9%, respectively. At a cut-off of 600 HU and area of no more than 12.1%, the accuracy, sensitivity, and specificity were 61.8%, 39.3%, and 100.0%, respectively. Compared with the cut-off value of 800 HU and an area percentage of no more than 93.8%, the sensitivity of cut-off values and minimum areas of 1050 HU and 93.6%, of 1150 HU and 98.4%, and of 600 HU and 12.1%, was gradually decreasing; however, their specificity was gradually increasing. This can provide an important basis for reducing the misdiagnosis and unnecessary surgical trauma.

概要

目的

探讨CT直方图在甲状腺良性孤立性粗钙化结节 (BSCN)诊断中的价值。

创新点

首次采用CT直方图来对甲状腺结节进行良恶性的 鉴别诊断,并找到有较好临床诊断价值截点值。

方法

收集2009年1月至2015年12月期间,经手术及病 理证实的甲状腺孤立粗钙化结节(粗钙化直径 ≥5 mm,周围无软组织)86例89枚,包括54例56 枚BSCNs和32 例33枚恶性孤立性粗钙化结节 (MSCNs)。在200~1500 HU的范围内,以50 HU 的N(4≤N≤30)倍为截点,共计27个,记录CT直 方图中BSCN和MSCN各截点及其所占面积百分 比的差异,通过ROC曲线确定诊断BSCN的最佳 截点及其面积百分比。

结论

在19组受试者工作特征曲线(ROC)面积超过0.7 的数据中,当800 HU和面积百分比≤93.8%时,准 确度最高,为75.3%,敏感度和特异度分别为 80.4%和66.7%;当1050 HU和百分比≤93.6%时, 准确度为71.9%,敏感度和特异度分别为60.7%和 90.9%;当1150 HU和百分比≤98.4%时准确度为 70.8%,敏感度和特异度分别为57.1%和93.9%;当 600 HU和百分比≤12.1%时准确度为61.8%,敏感 度和特异度分别为39.3%和100%。与截点800 HU 和面积百分比≤93.8%比较发现,尽管1050 HU和 百分比≤93.6%、1150 HU和百分比≤98.4%、600 HU 和百分比≤12.1%对BSCN诊断的敏感度有所降 低,但特异度显著升高,从而为BSCN患者减少 了不必要的手术创伤。