双能量 CT 碘图及标准化碘浓度对甲状腺癌的诊断价值

目的：探讨双能量CT碘图形态学与碘浓度测定对甲状腺癌的诊断价值。方法回顾性分析行双能量CT增强扫描且经手术病理证实的甲状腺结节患者，分别测量动、静脉期颈内动脉C T值，筛选C T值同时满足动脉期110～250 H U、静脉期70～110 HU共90例（恶性60例，良性30例）。测量正常甲状腺组织，良、恶性结节碘浓度，得出NICnod值（normalized iodine concen‐tration ，标准化碘浓度），比较良、恶性及正常组间甲状腺结节的差异。对结节形态学分析，分别观察：形态是否规则、沙砾样钙化、结节强化环不完整呈“强化残圈征”、结节突破甲状腺包膜呈“节段缺损征”在诊断恶性结节中的灵敏度、特异性及准确度，比较在碘图及普通图像上的差异。结果①甲状腺癌碘图上，形态不规则、结节强化环不完整呈“强化残圈征”、结节突破甲状腺包膜呈“节段缺损征”诊断为甲状腺癌的灵敏度、特异度及准确度均较普通 CT图像高（P均＜0．05），沙砾样钙化在碘图与普通图像上无差异（P＞0．05）。②正常与恶性组、正常与良性组及恶性与良性组 NICnod静脉期差异均有统计学意义（Z值分别为－3．092、－3．187、－2．660， P均＜0．05），动脉期良、恶性组差异无统计学意义。静脉期最佳 NICnod为0．76，小于该值诊断为恶性，受试者工作特征曲线（ROC）的曲线下面积（AUC）值为0．91，敏感度和特异度分别为74．61％、75．60％。③碘图形态学结合结节NICnod诊断甲状腺癌的灵敏度、特异度及准确度分别为：91．67％、86．67％、94．44％。结论双能量C T碘图形态学及碘浓度测量对甲状腺癌的定性诊断有价值。

The value of dual-energy CT iodine image and NICnod in diagnosis of thyroid cancer

Objective To investigate the value of dual‐energy CT iodine image morphology and iodine concentration in thyroid cancer diagnosis .Methods The patients underwent dual‐energy contrast scanning and confirmed with pathology results were en‐rolled .90 cases (60 malignant nodules and 30 benign nodules) were chosen with the CT value of internal carotid :110-250 HU at ar‐terial phase and 70-110 HU at venous phase .The iodine concentration of normal thyroid and neoplasms were measured respective‐ly ,as well as the NICnod (normalized iodine concentration) .Then the data was compared among each groups .The iodine image mor‐phology was also analyzed of each neoplasms ,and sensitivity ,specificity and accuracy were calculated .Results ①In the iodine image the characteristics of thyroid cancer ,including irregular shape ,invading neighbor structure and uncompleted enhanced ring around the tumor ,have significant differences compared with normal CT image (P all<0 .05) .Between iodine image and normal image ,the dis‐crete granular calcification has no difference (P>0 .05) .②There were significant differences in the venous phase NICnod value from normal groups ,malignant groups and benign groups (P<0 .05) .When diagnosed as malignant tumor ,the critical NICnod was under 0 .76 ,the area under the ROC curve of AUC value were 0 .91 ,the sensitivity and specificity were 74 .61% and 75 .60% ,respectively .③The sensitivity ,specificity and accuracy of iodine image combined with the NICnod to diagnose thyroid cancer were 91 .67% ,86 .67% , 94 .44% ,respectively .Conclusion Dual‐energy CT iodine image morphology and iodine concentration have important value in thyroid cancer diagnosis .