The Study Value Of ～(99m)Tc-MIBI Imaging For The Follow-up Patients With Differentiated Thyroid Carcinoma After Iodine-131 Ablation Residual Thyroid Tissue

Objective: To evaluate if we can completely substitute "Tc-MIBI imaging for iodine-131 whole body scanning for the follow-up of patients with differentiated thyroid carcinoma after iodine-131 therapy so as to modulate therapetuic plans and make follow-up schemes. Methods: Thirty-seven patients with differentiated thyroid carcinoma after operation and iodine-131 therapy were enrolled in the study. ^99mTc-MIBI Imaging was performed after 4⁶ weeks withdrawl of thyroxine and 30-day' s diet without iodine. The anterior static images of thyroid were acquired at 15min and 30min after injection of "Tc-MIBI 370⁷40 MBq (10²0mCi ) . Iodine-131 whole body scanning was undergone 40⁴8 hours after oral administration of a diagnostic dosage(185 MBq). We make the computer sketch the region of interest (ROI) and calculate the uptake ratio of T/N at 15min, 30 min after ^99mTc-MIBI injection and the uptake ratio of T/N of iodine-131 whole body scanning. Finally these results were analyzed and compared.Results:Regard iodine-131 whole body scanning as gold standard. Qualitative analysis of ^99mTc-MIBI imaging showed the sensitivity, specificity and accuary were 77%, 58% and 70%. In this study, there were 44 person-times which there were still thyroid tissue remained after iodine-131 therapy, and quantitative analysis showed there were no significant differences (P>0. 05) between the uptake ratio of T/N after ^99mTc-MIBI injection at 15min and the one at 30min. But each of the two uptake ratio of T/N was lower than the one of iodine-131 whole body scanning. This told us that there were statisticsmeanings(P<0.01). To 24 patients whose thyroid were completely ablated, there were no significant differences between the uptake ratio of T/N after "Tc-MIBI injection at 15min and the one at 30min(P>0. 05). But each of the uptake ratio of T/N was higher than the one of the iodine-131 whole body scanning, which meaned there were statics meanings (P<0. 01). In the first period of treatment, there were no significant differences between the the UR of T/N after "Tc-MIBI injection at 15min and the one at 30min in 31 patients (P>0. 05). But each of them was lower than the one of iodine-131 whole body scanning. That is to say there were statistic meanings (p<0.01). The same as the secondary period of treatment. The UR of T/N of the "Tc-MIBI imaging in the first period of treatment after the treating of iodine-131 compared with the one in the secondary period of treatment showed that there was significant difference, both at 15min and at 30min(P<0. 01). The UR of T/N in the secondary period of treatment was lower than the one in the first period of treatment. And the UR of T/N of iodine-131 whole body scanning in the first period of treatment after the treating of iodine-131 compared with the one in the secondary period of treatment showed that there was significant difference(P<0.01). After the treating of iodine-131, we acquired the imaging at 15min after the injection of "Tc-MIBI. The UR of T/N of the imaging in the secondary period of treatment droped by 1. 13 than the one in the first period of treatment. Similarly, The UR of T/N of the imaging at 30min in the secondary period of treatment droped by 1. 06 than the one in the first period of treatment. The UR of T/N of iodine-131 whole body scanning in the secondary period of treatment after the treating of iodine-131 droped averagely by 6.21 than the one in the first period of treatment. On the average, The UR of T/N of iodine-131 whole body scanning droped obviously than the one of "Tc-MIBI injection at 15min and 30min before and after treating. Conclusion: The "Tc-MIBI imaging has some clinical significance to thefollow-up of patient with DTC after operation and iodine-131 therapy. To the follow-up of patients who are unwilling to stop taking thyroid hormone or unsuitable for stopping, it is a good way to substitute "Tc-MIBI imaging for the iodine-131 whole body scanning. But we can not completely substitute ""Tc-MIBI imaging for iodine-131 whole body scanning to modulate therapetuic pla...