Relationship between the peripheral dose and radioactive counts of 125I seeds detected by SPECT/CT

VernacularTitle:SPECT/CT探测125I粒子放射性浓聚处计数与周围剂量的关系
Author: Xianzhi ZHAO ; Hongtao ZHANG ; Xuemin DI ; Shuangchen YANG ; Chen ZHANG ; Jinxin ZHAO ; Zezhou LIU ; Huimin YU ; Juan WANG
Keywords: Brachytherapy; Iodine radioisotopes; Radiation dosage; Tomography,emission-computed,single-photon; Tomography,X-ray computed; Phantoms,imaging
From: Chinese Journal of Nuclear Medicine and Molecular Imaging 2017;37(6):351-354
CountryChina
Language:Chinese
Abstract: Objective To explore the relationship between the peripheral dose and radioactive counts of 125I seeds detected by SPECT/CT.Methods Six 125I seeds(1.48×107 Bq, 1.85×107 Bq, 2.22×107 Bq, 2.59×107 Bq, 2.96×107 Bq, 3.33×107 Bq) were put into the solid water phantoms respectively. SPECT/CT was applied to scan the seeds. The radioactive counts (x) at the distance of 1-15 mm from the center of seeds were recorded respectively, while the corresponding doses (y, cGy) were calculated. SPSS 18.0 was used to analyze the relationship between the radioactive counts and peripheral dose. Results There was an exponential relationship between the peripheral dose of 125I seeds and the radioactive counts. The formula was as follow: y=507.849×1.004x. Conclusion SPECT/CT can visualize the peripheral dose of 125I seed, which may provide a method for dosimetric verification after brachytherapy.