目的 探究低剂量MSCT对甲状腺 良恶性结节的诊断效果。方法 选取2014 年6月至2016年12月我院收治的甲状腺 结节病变患者84例，经病例检查分为良 性组患者70例，恶性组患者14例。采用 CT平扫和同层动态灌注扫描，计算BF、 BV、TTP、MTT等参数，进行差异比较。结 果 良性组的MSCT特征主要为结节形状规 则、边缘清晰、呈条片状钙化，恶性组的 MSCT特征主要为结节形状不规则、边缘模 糊、呈颗粒状钙化，两组的MSCT特征具 有统计学差异(P＜0.05)；甲状腺结节良 性患者经强化扫描后，具体表现为均匀 强化，8.6%的患者表现为完整的环形强 化，甲状腺结节恶性患者经强化扫描后， 具体表现为肿瘤组织周围呈现半岛样强 化或残圈样强化，两组差异存在统计学 意义(P＜0.05)；甲状腺结节恶性组患者 TTP、MTT水平分别为(24.69±1.74)s、 (10.51±0.31)s，均低于甲状腺结节良性 组患者TTP、MTT水平(30.14±7.65)s、 (17.26±11.65)s，两组患者TTP、MTT水 平均具有统计学差异(P＜0.05)；结论 低 剂量MSCT灌注成像可以在一定程度上反应 患者甲状腺阶级血流动力学情况，降低患 者受辐射量，对于甲状腺良恶性结节的诊 断具有一定的参考作用。

Objective To investigate the effect of low dose MSCT on thyroid benign and malignant nodules. Methods From June 2014 to December 2016, 84 patients with thyroid nodular lesions admitted in our hospital were divided into benign group (n=70) and malignant group (n=14). The parameters of BF, BV, TTP, MTT and so on were calculated by CT scan and stratified dynamic perfusion scan. Results The MSCT features of the benign group were mainly nodular shape, with clear margins and granular calcification. The MSCT features of the malignant group were irregular nodules, blurred and granular calcification. The MSCT features of the two groups were (P<0.05), patients with benign thyroid nodules after intensive scan, the specific performance of uniform enhancement, 8.6% of patients showed complete ring enhancement, thyroid nodular malignant patients after intensive scan, the specific performance of the tumor (P<0.05). The levels of TTP and MTT in patients with malignant thyroid nodules were (24.69±1.74) s, (10.51±0.31) s, respectively, and there was significant difference between the two groups (P<0.05). Conclusion The low dose of TTP and MTT in patients with benign thyroid nodules were significantly lower than those in benign thyroid nodules (30.14±7.65) s and (17.26±11.65) MSCT perfusion imaging can be a certain extent to respond to patients with thyroid class hemodynamic conditions, reduce the amount of radiation by patients, for the diagnosis of thyroid benign and malignant nodules have a certain reference use.