目的 探讨131I-SPECT/CT断层融合显像技术在分化型甲状腺癌（DTC）转移灶定性、定位诊断中的临床价值。方法 选择69例确诊DTC患者，甲状腺全切或次全切术后，口服碘化钠（131I）治疗剂量3.70～7.40 GBq后5～7d，行全身平面显像（131I-WBS），随后在同一床位进行SPECT断层扫描和CT扫描，扫描结束后进行图像融合处理。检查结果与病理或其他影像学检查以及临床随访结果对比，分析确定DTC转移灶的定性、定位诊断，并做对比分析。结果 69例患者中，临床证实转移灶共计186处；平面显像170处、融合显像179处发现异常摄碘浓聚灶；其中平面显像有160处，融合显像有174处与病理、螺旋CT、MRl以及超声等检查结果一致，其诊断灵敏度分别为86%（160/186）、93.5%(174/186)，定性、定位准确性分别为81.6%（160/196）、91.1%（174/191）；两种方法的诊断灵敏度差异有统计学意义（χ2= 5.74，P＜0.05），定性、定位准确性差异也有统计学意义（χ2= 7.33，P＜0.01）。结论131I-SPECT/CT断层融合显像能够精准的定性、定位DTC的复发和转移，克服污染灶、组织重叠等因素的影响，较平面显像具有更高的灵敏度和准确性，用于DTC患者的临床分期、疗效和治疗方案的制定，具有重要的临床价值。

Objective To explore the clinical value of 131I SPECT-CT fusion imaging in location and qualitative diagnosis of metastases of differentiated thyroid carcinoma (DTC). Methods 69 patients who had been diagnosed as differentiated thyroid cancer with total or subtotal resection, took 131I orally with treatment dose 3.70 ~ 7.40 GBq. The patients did whole-body planar imaging (131I -WBS) after 5 ~ 7 days, and then performed the SPECT and CT scans at the same bed location. The results were compared with pathological or other imaging examination and clinical follow-up results, to analyze and determine the location and qualitative diagnosis of DTC metastases. Results The total 186 metastases were found in 69 patients. Abnormal 131I uptake density collective focus were found in 170 planar imaging and 179 fusion imaging, in which there were 160 planar imaging and 174 fusion imaging that were consistent with the pathological, spiral CT, MRI and ultrasound examination results. The diagnostic sensitivity of planar imaging and SPECT-CT were 86% (160/186), 93.5% (174/186) respectively. The qualitative and localization accuracy were 81.6% (160/196), 91.1% (174/191) respectively. There was significantly difference on diagnostic sensitivity and accuracy between two methods (P<0.05). Conclusion 131I SPECT-CT fusion imaging can precisely locate and determine the nature of DTC recurrence and metastasis, overcome the influences from pollution focus, organizational overlap and other factors. Compared with planar imaging, it has higher sensitivity and accuracy. It has important clinical value and can be used in clinical staging of DTC patients, curative effect and the setting of treatment programs.