Hippeläinen Eero T, Tenhunen Mikko J, Mäenpää Hanna O, Heikkonen Jorma J, Sohlberg Antti O
aClinical Research Institute HUCH Ltd bDepartment of Physics, University of Helsinki cHUS Medical Imaging Center, Clinical Physiology and Nuclear Medicine, University of Helsinki and Helsinki University Hospital dDepartment of Oncology, Cancer Centre, Helsinki University Central Hospital, Helsinki eJoint Authority for Päijät-Häme Social and Health Care, Department of Clinical Physiology and Nuclear Medicine, Lahti, Finland fHERMES Medical Solutions, Stockholm, Sweden.
Nucl Med Commun. 2017 May;38(5):357-365. doi: 10.1097/MNM.0000000000000662.
The aim of this work is to validate a software package called Hermes Internal Radiation Dosimetry (HIRD) for internal dose assessment tailored for clinical practice. The software includes all the necessary steps to perform voxel-level absorbed dose calculations including quantitative reconstruction, image coregistration and volume of interest tools.
The basics of voxel-level dosimetry methods and implementations to HIRD software are reviewed. Then, HIRD is validated using simulated SPECT/CT data and data from Lu-DOTATATE-treated patients by comparing absorbed kidney doses with OLINDA/EXM-based dosimetry. In addition, electron and photon dose components are studied separately in an example patient case.
The simulation study showed that HIRD can reproduce time-activity curves accurately and produce absorbed doses with less than 10% error for the kidneys, liver and spleen. From the patient data, the absorbed kidney doses calculated using HIRD and using OLINDA/EXM were highly correlated (Pearson's correlation coefficient, r=0.98). From Bland-Altman plot analysis, an average absorbed dose difference of -2% was found between the methods. In addition, we found that in Lu-DOTATATE-treated patients, photons can contribute over 10% of the kidney's total dose and is partly because of cross-irradiation from high-uptake lesions close to the kidneys.
HIRD is a straightforward voxel-level internal dosimetry software. Its clinical utility was verified with simulated and clinical Lu-DOTATATE-treated patient data. Patient studies also showed that photon contribution towards the total dose can be relatively high and voxel-level dose calculations can be valuable in cases where the target organ is in close proximity to high-uptake organs.
本研究旨在验证一款名为Hermes内部辐射剂量测定法（HIRD）的软件包，该软件专为临床实践中的内部剂量评估而设计。该软件包括进行体素级吸收剂量计算所需的所有步骤，包括定量重建、图像配准和感兴趣区工具。
回顾了体素级剂量测定方法的基本原理以及在HIRD软件中的实现。然后，通过将肾脏吸收剂量与基于OLINDA/EXM的剂量测定法进行比较，使用模拟的SPECT/CT数据和来自接受镥-奥曲肽治疗患者的数据对HIRD进行验证。此外，在一个示例患者病例中分别研究了电子和光子剂量成分。
模拟研究表明，HIRD能够准确再现时间-活度曲线，并且对肾脏、肝脏和脾脏产生的吸收剂量误差小于10%。从患者数据来看，使用HIRD和OLINDA/EXM计算的肾脏吸收剂量高度相关（Pearson相关系数，r = 0.98）。通过Bland-Altman图分析，发现两种方法之间的平均吸收剂量差异为-2%。此外，我们发现，在接受镥-奥曲肽治疗的患者中，光子对肾脏总剂量的贡献可超过10%，部分原因是靠近肾脏的高摄取病灶的交叉照射。
HIRD是一款简单的体素级内部剂量测定软件。通过模拟和临床接受镥-奥曲肽治疗患者的数据验证了其临床实用性。患者研究还表明，光子对总剂量的贡献可能相对较高，并且在靶器官靠近高摄取器官的情况下，体素级剂量计算可能很有价值。
