Use of Visible Human Data For Patient Dosimetry

描述（由申请人提供）：放射免疫疗法通过注射带有发射放射性核素的带电粒子标记的单克隆抗体来治疗癌组织。然而，在过去的30年里，核医学一直依赖于60年代末产生的粗糙的解剖模型。最近的数据表明，使用这些模型计算的剂量对很大一部分患者群体来说是不正确的。另一方面，来自可见人体计划（VHP）的CT、MR和冷冻切片图像提供了真实和最完整的人体解剖学数字数据库。因此，假设由可见人体计划的极精细图像构建的全身患者模型可以显着改善接受内源性放射性同位素治疗的患者的放射剂量学。虽然先前的研究已经解决了处理巨大的VHP辐射传输图像的关键问题，但关于如何将最近的进展转化为核医学的患者剂量学的信息很少。为了满足这些需求，本课题拟实现以下具体目标：1)通过对VHP获得的0.33 mm x 0.33 mm分辨率的男性和女性尸体冷冻切片图像进行处理、分割和分类，建立成年男性和成年女性患者全身计算模型。2)将这些三维、高分辨率、分段断层扫描患者模型实现到最先进的辐射传输代码包中，以计算选定的核医学剂量学参数。3)评估在接受典型核医学手术的成年患者中，内部器官结构的改进解剖表征对器官剂量估计的影响程度。

DESCRIPTION (provided by applicant): Radioimmunotherapy treats cancerous tissues by injecting monoclonal antibodies labeled with charged particle emitting radionuclides. However, for the past 30 years, nuclear medicine has replied on crude anatomic models that originated in late 60's. Recent data show that doses calculated using these models are NOT correct for a very large portion of the patient population. On the other hand, CT, MR and cryosection images from the Visible Human Project (VHP) have provided realistic and most complete digital database on human anatomy. Therefore, it is hypothesized that whole-body patient models, constructed from extremely fine images of the Visible Human Project, can dramatically improve radiation dosimetry for patients undergoing internally administered radioisotope therapy. Although a previous study has solved critical issue on handling huge VHP images for radiation transport, little information exist on how to translate the recent advance into patient dosimetry for nuclear medicine. To address these needs, a research project is proposed to achieve the following Specific Aims: 1) To develop an adult male and an adult female patient whole-body computational model by processing, segmenting and classifying the 0.33 mm x 0.33 mm resolution cryosection images of the male and female cadavers obtained from the VHP. 2) To implement these 3-D, high-resolution, segmented tomographic patient models into the state-of-the-art radiation transport code packages to calculate selected nuclear medicine dosimetric parameters. 3) To evaluate the degrees to which improved anatomical representation of internal organ structures influences estimate of organ dose in adult patients who are undergoing a typical nuclear medicine procedure.