目的 评价¹³¹I-SPECT/CT融合显像对¹³¹I全身显像（WBS）在分化型甲状腺癌（DTC）诊治中的增益价值。方法 ¹³¹I治疗后82例患者分别行WBS及SPECT/CT显像。分析SPECT/CT显像对浓聚灶定位定性的判断能力，并与WBS比较。分析SPECT/CT显像探查不聚碘病灶的能力。评估SPECT/CT显像对转移部位诊断、临床分期和治疗方案制定的影响。结果 WBS发现聚碘灶203个，SPECT/CT显像定位后发现，WBS正确判断聚碘灶部位89个(43.84%)，判断正确率最高的部位依次为残余甲状腺74.24%(49/66)和骨62.86%(22/35)。WBS判断聚碘灶性质为良性52个，恶性36个，不确定115个；SPECT/CT显像判断为良性94个，恶性79个，不确定30个。SPECT/CT显像给出的“不确定”判断30个(14.78%)，明显少于WBS的115个(56.65%)，差异有统计学意义(χ2=77.51，P<0.01)。SPECT/CT显像发现不聚碘的病灶6处，最终均证实为转移。82例患者中，与WBS作出的最初诊断相比，SPECT/CT显像改变了14例(17.07%)转移部位的诊断，改变了5例(6.1%)临床分期的诊断，并最终改变了23例(28.05%)患者的治疗方案。结论 SPECT/CT显像对于聚碘灶的鉴别诊断、不聚碘病灶的探查作用明显，能提高诊断的准确性，帮助调整治疗方案。SPECT/CT显像可以弥补平面显像的不足，对于DTC的诊治有增益价值。

Objective To investigate the incremental value of ¹³¹I-SPECT/CT fusion imaging over ¹³¹I whole-body scintigraphy (WBS) in the management of patients with differentiated thyroid carcinoma (DTC). Methods Eighty-two patients with DTC underwent both WBS and SPECT/CT imaging after ¹³¹I therapy. The capacity of location and qualitative analysis of radioiodine avid lesions of SPECT/CT imaging was compared with that of WBS. The capacity of SPECT/CT imaging in detecting non-radioiodine avid lesions was analysed. The impact of SPECT/CT imaging on diagnosis of metastases, clinical staging and therapeutic strategy was evaluated. Results Two hundred and three radioiodine avid lesions were detected by WBS. Eighty-nine of them (43.84%) were located by WBS, which was verified by SPECT/CT imaging. Thyroid remnant and bone were the regions with highest accuracy, with accuracy rates of 74.24% (49/66) and 62.86% (22/35) respectively. WBS determined 52 benign radioiodine avid lesions, 36 malignant ones and 115 uncertain ones, and SPECT/CT imaging determined 94, 79 and 30 respectively. The percent of uncertain radioiodine avid lesions determined by SPECT/CT imaging was significantly lower than that determined by WBS (14.78% vs 56.65%, χ2=77.51, P<0.01). Besides, 6 non-radioiodine avid metastatic lesions were detected by SPECT/CT imaging. Among all the 82 patients, 14 (17.07%) were changed about the diagnosis of metastasis, 5 (6.1%) were changed about the clinical stage, and 23 (28.05%) were changed about the therapeutic strategy through SPECT/CT imaging. Conclusion SPECT/CT fusion imaging has incremental value in differentiating radioiodine avid lesions, detecting non-radioiodine avid lesions, improving accuracy of diagnosis, and adjusting therapeutic strategy of DTC.