微小甲状腺癌的CT特点

CT feature of microcarcinoma of thyroid

目的 探讨微小甲状腺癌（MCT）的CT表现特点.方法 回顾性分析经手术、病理证实的47例共50枚直径在0.5～1.0 cm MCT的CT资料.结果 50枚瘤体中,38枚瘤体CT平扫呈均匀低密度,增强后不同程度均匀强化；33枚瘤体出现甲状腺平扫边缘中断征；增强后30枚瘤体轮廓较平扫模糊,瘤体相对低密度范围缩小；31枚瘤体不规则形；15枚瘤体钙化,其中细颗粒状钙化13枚；CT平扫未显示的12枚瘤体中,合并甲状腺炎10枚.结论 瘤体形态不规则、甲状腺平扫边缘中断征、瘤体增强后相对低密度区小于平扫、细颗粒状钙化、瘤体周围多发小淋巴结有助于MCT的诊断；甲状腺炎可以掩盖MCT,需引起注意.

Objective To evaluate the imaging feature of microcarcinoma of thyroid with CT.Methods CT findings of 50 lesions in 47 patients with microcarcinoma of thyroid （ dimeter,0.5 to 1.0 cm） were retrospectively analyzed.All of the patients had pathological diagnosis.Results Of the 50 lesions,38 lesions showed homogeneous low density on non-enhanced CT and various degree of enhancement on postcontrast CT. Thirty-three lesions showed discontinuous edge of the thyroids on non-enhanced CT. The boundary of 30 lesions became unclear on post-contrast CT relative to non-enhanced CT and the extension of low density of lesions decreased. Theshape of 31 lesions were irregular. Fifteen lesions showed calcifications,with granular calcifications in 13 lesions.Ten lesions were complicated with thyroiditis.Conclusions Irregular shape,discontinuous edge of the thyroids,the shrinkage of low density of lesions on post-contrast CT relative to non-enhanced CT,granular calcifications and multiple small lymph node around lesions indicate the diagnosis of microcarcinoma of the thyroid.It should be noted that thyroiditis can cover up microcarcinoma of thyroid.