Differentiated thyroid cancer has been treated with radioiodine for almost 80 years, although controversial questions regarding radiation-related risks and the optimisation of treatment regimens remain unresolved. Multi-centre clinical studies are required to ensure recruitment of sufficient patients to achieve the statistical significance required to address these issues. Optimisation and standardisation of data acquisition and processing are necessary to ensure quantitative imaging and patient-specific dosimetry. A European network of centres able to perform standardised quantitative imaging of radioiodine therapy of thyroid cancer patients was set-up within the EU consortium MEDIRAD. This network will support a concurrent series of clinical studies to determine accurately absorbed doses for thyroid cancer patients treated with radioiodine. Five SPECT(/CT) systems at four European centres were characterised with respect to their system volume sensitivity, recovery coefficients and dead time. System volume sensitivities of the Siemens Intevo systems (crystal thickness 3/8″) ranged from 62.1 to 73.5 cps/MBq. For a GE Discovery 670 (crystal thickness 5/8″) a system volume sensitivity of 92.2 cps/MBq was measured. Recovery coefficients measured on three Siemens Intevo systems show good agreement. For volumes larger than 10 ml, the maximum observed difference between recovery coefficients was found to be ± 0.02. Furthermore, dead-time coefficients measured on two Siemens Intevo systems agreed well with previously published dead-time values. Results presented here provide additional support for the proposal to use global calibration parameters for cameras of the same make and model. This could potentially facilitate the extension of the imaging network for further dosimetry-based studies.

中文翻译：

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作为MEDIRAD项目的一部分，为欧洲多中心甲状腺癌放射碘治疗的剂量学研究建立定量SPECT成像网络

分化型甲状腺癌已经用放射碘治疗了近80年，尽管关于放射相关风险和治疗方案优化的争议性问题仍未解决。需要进行多中心临床研究，以确保招募足够的患者，以达到解决这些问题所需的统计学意义。数据采集​​和处理的优化和标准化对于确保定量成像和特定于患者的剂量测定是必不可少的。在欧盟MEDIRAD联盟中建立了一个欧洲中心网络，该中心能够对甲状腺癌患者进行放射碘治疗的标准化定量成像。该网络将支持一系列并发的临床研究，以确定放射碘治疗的甲状腺癌患者的准确吸收剂量。在欧洲四个中心的五个SPECT（/ CT）系统的系统容积敏感性，恢复系数和停滞时间方面进行了表征。西门子Intevo系统（晶体厚度3/8英寸）的系统体积灵敏度范围为62.1到73.5 cps / MBq。对于GE Discovery 670（晶体厚度5/8英寸），系统体积灵敏度为92.2 cps / MBq。在三个西门子Intevo系统上测得的回收系数显示出良好的一致性。对于大于10 ml的体积，发现回收系数之间的最大观测差异为±0.02。此外，在两个西门子Intevo系统上测得的空载时间系数与以前发布的空载时间值非常吻合。此处提供的结果为使用相同品牌和型号的摄像机使用全局校准参数的建议提供了额外的支持。