基于切伦科夫效应的裸鼠甲状腺131I多模态显像

目的 采用切伦科夫发光断层成像(CLT)和γ显像进行裸鼠甲状腺摄取131I的多模态成像,探索CLT与γ显像之间的相关性.方法 先对4只裸鼠体质量(21±3)g]尾静脉注射1.67×107 Bq 131I,在注药后0.5、3、12及24h均分别行CLT和γ显像.采用基于漫射方程(DE)的切伦科夫光源重建方法重建裸鼠体内131I的生物分布及在不同采集时间点甲状腺摄取131I的切伦科夫光的功率.对采集的γ显像图像勾画ROI,获得γ计数的平均值,对CLT 1311的切伦科夫光的功率和γ显像获取的γ计数行直线相关分析.结果 甲状腺摄取131I的切伦科夫光的功率在0.5、3、12和24h分别为7.80×10-3、1.62×10-12、2.20×10 - 12和2.68×10-12 W.甲状腺摄取131I的切伦科夫光的功率随放射性药物注射时间的延长而逐渐增加.γ显像结果表明131I在裸鼠腹部的摄取逐渐降低,而在甲状腺的摄取越来越高,CLT与γ显像结果具有较好的相关性(r2 =0.7620,P＜O.05).结论 CLT具有临床甲状腺成像、甲状腺疾病诊断和疗效判断的潜力.

Multimodality imaging of ^131I uptake in nude mice thyroid based on Cerenkov radiation

Objective To perform the multimodality ^131I thyroid imaging using Cerenkov lumines- cence tomography （CLT） and gamma imaging, and to compare the results of CLT and gamma imaging. Meth- ods The nude mice （ n = 4, mass ： （21±3） g） were injected with 1.67 ×107 Bq ^131 I. CLT and gamma im- aging were acquired at 0. 5, 3, 12 and 24 h after the injection. Three-dimensional biodistribution of ^131I uptake in thyroid was reconstructed using Cerenkov source reconstruction method based on the diffusion equa- tion （DE）, and the reconstructed power of ^131I in different acquisition time points was obtained. Additional- ly, the ROIs were drawn over the gamma images of the mouse neck, and the counts were read. The correla-tion between the reconstructed power of CLT and gamma ray counts of gamma imaging was analyzed. Re- suits The power of ^131I uptake in thyroid at 0. 5, 3, 12 and 24 h were 7. 80 ×10^-13, 1.62×10^-12,2.20× 10-12 and 2. 68×10^-12 W, respectively. CLT results showed that reconstructed power increased with the increasing of acquisition time. Gamma imaging results indicated that ^131I uptake decreased in abdomen and in- creased in thyroid with the collection time. The results of CLT were consistent with that of gamma imaging （r^2 = 0.7620, P 〈 0. 05 ）. Conclusion CLT has the potential to identify and monitor functioning thyroid tissue at before and （or） after^131I treatment.