甲状腺微小乳头状癌高b值扩散加权成像的诊断价值  

Utility of High b-Value Diffusion Weighted MRI in Diagnosing Papillary Thyroid Microcarcinoma

作　　者：王代兵[1] 王庆军[2] 

机构地区：[1]北京军区北戴河疗养院放射科,066001 [2]海军总医院医学影像科,北京100048

出　　处：《临床放射学杂志》2017年第8期1089-1093,共5页Journal of Clinical Radiology

摘　　要：目的探讨高b值扩散加权成像(DWI)诊断甲状腺微小乳头状癌的价值。方法选择因甲状腺结节拟行手术患者75例,术前均常规进行甲状腺DWI检查,分别测量不同b值DWI图像中单个结节与邻近正常甲状腺组织信号强度的比值(R值:R0、R800、R2000)以及高b值DWI图像中R值较低b值DWI图像中R值变化情况(Type-R800/0、Type-R2000/0、Type-R2000/800:Ⅰ型为上升型、Ⅱ型为平台型、Ⅲ型为下降型),再通过与术后病理检查结果对照,评估上述诊断指标对甲状腺微小乳头状癌与良性结节的鉴别诊断价值。结果共有良性结节53个和微小乳头状癌42个纳入结节测量和统计分析。(1)单变量分析结果显示,R值中的R0和R2000,以及R值变化类型中的Type-R800/0、Type-R2000/0、Type-R2000/800,在甲状腺微小乳头状癌与良性结节间显著(P﹤0.05)。(2)多变量分析结果显示,R0(敏感度和特异性分别为83.26%和64.78%)以及Type-R2000/0(敏感度和特异性分别为93.81%和85.63%),可作为甲状腺微小乳头状癌的独立诊断指标(P值分别﹤0.05和﹤0.001);如果将R0和Type-R2000/0联合诊断,特异性可进一步提高(87.59%)。结论高b值DWI对于甲状腺微小乳头状癌与良性结节鉴别诊断价值较高。Objective The objective of this study was to evaluate the role of magnetic resonance（ MR） high b-value diffusion-weighted imaging（ DWI） in diagnosing thyroid microcarcinomas. Methods A total of 75 patients with thyroid nodules planned for thyroid operation underwent thyroid high b-value DWI. A total of three b-values were used： 0,800 and2000 s/mm^2. Ratios（ Rs） of a thyroid nodule to adjacent normal thyroid tissue on DWIs respectively with the three different b-values were measured as three diagnostic indicators： R0,R800 and R2000. Change types of the Rs for the same thyroid nodule on DWIs with relatively high b-value to low b-value were performed as another three diagnostic indicators：Type-R800/0,Type-R2000/0 and Type-R2000/800. Three possible types were defined for each comparison： Type Ⅰ（ increasing pattern）,Type Ⅱ（ plateau pattern） and Type Ⅲ（ decreasing pattern）. Compared with postoperative pathology,the values of the 6 indicators in diagnosing benign thyroid nodules and papillary carcinomas were evaluated by univariable analysis,multivariable analysis and receiver operating characteristic curve（ ROC）. Results A total of 53 benign thyroid nodules and 42 thyroid microcarcinomas proved by pathology underwent high b-value DWI and were enrolled into statistical analysis. The univariable analysis showed statistical differences were found in R0,R2000,Type-R800/0,Type-R2000/0and Type-R2000/800 between the benign thyroid nodules and microcarcinomas. The multivariate analysis showed that R0（ sensitivity and specificity： 83. 26% and 64. 78%） and Type-R2000/0（ sensitivity and specificity： 93. 81% and 85. 63%） were the independent indicators for diagnosing benign thyroid nodules and microcarcinomas（ P ﹤ 0. 05 and P ﹤0. 001）. If the R0 and Type-R2000/0 was combined,the diagnostic specificity increased to 87. 59%. Conclusion High b-value DWI can contribute to differentiating thyroid microcarcinomas from benign thyroid nodules.

关 键 词：甲状腺微小乳头状癌 磁共振扩散成像 鉴别诊断 

分 类 号：R445.2[医药卫生—影像医学与核医学] R736.1[医药卫生—诊断学]