Dose calculation for radiotherapy with protons and heavier ions deals with a large volume of path integrals involving a scattering power of body tissue. This work provides a simple model for such demanding applications. There is an approximate linearity between RMS end-point displacement and range of incident particles in water, empirically found in measurements and detailed calculations. This fact was translated into a simple linear formula, from which the scattering power that is only inversely proportional to residual range was derived. The simplicity enabled analytical formulation for ions stopping in water, which was designed to be equivalent with the extended Highland model and agreed with measurements within 2% or 0.02 cm in RMS displacement. The simplicity will also improve the efficiency of numerical path integrals in the presence of heterogeneity.
Relationship between electron density and effective densities of body tissues for stopping, scattering, and nuclear interaction of proton and ion beams
Proton therapy range uncertainty reduction using vendor-agnostic tissue characterization on a virtual photon-counting CT head scan
Vinaver Medical(维纳弗医学);Faculty of Medicine, University of Novi Sad(诺维萨德大学医学院);Carl E. Ravin Advanced Imaging Laboratories and Center for Virtual Imaging Trials, Duke University(杜克大学卡尔·E·拉文先进成像实验室与虚拟成像试验中心);Centro Nazionale di Adroterapia Oncologica (CNAO)(国家肿瘤质子治疗中心);Department of Radiology, Duke University(杜克大学放射系)
Neutron relative effectiveness factors in Boron Neutron Capture Therapy: estimation of their values from the secondary charged particles and evaluation of weighted kerma factors for a standard tissue
Optimal particle type and projection number in multi-modality relative stopping power acquisition
质子射线照相术结合X射线计算机断层成像(CT)已被提出,以获得患者特异性校准曲线,并减少带电粒子治疗癌症的范围不确定性。本研究的主要目的是确定最佳的带电粒子产生的射线照相,并确定最佳数量的必要的投影,以获得最小的范围误差。三种带电粒子被认为是产生射线照相:质子(p-rad),氦离子(α-rad)和碳离子(c-rad)。问题公式被视为最小二乘优化,argmin_x(||Ax-b||_2^2),其中投影矩阵A表示每种材料中每种粒子穿过的累积路径,b是表示为穿过的水等效厚度(WET)的带电粒子列表模式射线照相术,X是待优化的相对阻止本领(RSP)图。使用Geant 4 Monte Carlo(MC)工具包和拟人成人头部模型模拟带电粒子射线照相。A是通过使用凸包检测结合三次样条路径计算通过X射线CT的颗粒轨迹来确定的。对于所有颗粒类型,评估使用多个投影的影响(从1到6个投影)。在这项研究中,组织分割方法也进行了研究,可达到的精度。最好的结果(平均RSP误差低于0.7%,范围误差低于1毫米),获得了a-rad时,使用3个投影。单次α-rad照射体模的剂量为8 \muGy,低于X线摄影剂量。
Stopping power monitoring during proton therapy by means of prompt gamma timing: first experimental results with a homogeneous phantom
Universität zu Lübeck(吕贝克大学);INFN sezione di Torino(都灵意大利国家核物理研究所);State University of Santa Cruz(圣克鲁斯州立大学);Fondazione CNAO(CNAO基金会);Università degli Studi di Torino(都灵大学)
Proposal of a consistent value for the mean excitation energy of liquid water using advanced modeling, detailed simulations and precission proton Bragg curves
Universidad de Murcia(穆尔西亚大学);Universitat d’Alacant(阿利坎特大学);Instituto de Pesquisas Energéticas e Nucleares(能源与核研究所)
Reconstruction of proton relative stopping power with a granular calorimeter detector model
University of Kaiserslautern-Landau(凯泽斯劳滕-兰道大学);University of Bergen(卑尔根大学);HUN-REN Wigner Research Centre for Physics(匈牙利研究与教育网络维格纳物理研究中心);Research and Production Enterprise ”LTU” (RPELTU)(LTU研究与生产企业);Institute for Subatomic Physics, Utrecht University/Nikhef(乌得勒支大学/尼赫夫亚原子物理研究所);St. Petersburg University(圣彼得堡大学);Western Norway University of Applied Sciences(西挪威应用科学大学)
Analytical Model of Prompt Gamma Timing for Spatiotemporal Emission Reconstruction in Particle Therapy
Universität zu Lübeck(吕贝克大学);Institute of Medical Engineering, Universität zu Lübeck(吕贝克大学医学工程研究所);Istituto Nazionale di Fisica Nucleare, Sezione di Torino(意大利国家核物理研究所都灵分部);Università degli Studi di Torino(都灵大学)
Analysis of time-profiles with in-beam PET monitoring in charged particle therapy
背景资料:在带电粒子治疗中利用PET成像的治疗验证通常通过将空间分布的测量结果与蒙特卡罗(MC)预测进行比较来完成。然而,衰减曲线可以提供关于治疗和被照射组织的额外的独立信息。到目前为止,大多数研究都集中在长时间间隔上。在这里,我们调查的可靠性MC预测的空间和时间(衰变率)的轮廓照射后不久,我们展示了如何衰变率可以给出一个指示的元素,其中的幻影组成。方法和材料:在Bronowice质子治疗中心的回旋加速器中心,在临床和接近临床的条件下对各种幻影进行了辐照。使用平面16 x 16 cm $^2$ PET系统采集PET数据。用FLUKA程序模拟了粒子间的相互作用和光子在体模中的传播。分析包括实验数据和MC模拟的空间和时间分布之间的比较,以及拟合程序,以获得各种同位素的贡献在幻影。结果和结论:在一维空间和衰变率分布中,数据和MC预测之间有很好的一致性。通过用多个简单指数拟合衰变速率获得的$^{11}$ C、$^{15}$ O和$^{10}$ C的分数通常与MC预期一致。与MC中的预测值相比,我们发现数据中的$^{10}$ C略微过量,这在PE体模中尤其明显。
Application of instruments of nuclear physics to the calculation of theoretical dose distributions in various organs of the human body for beams used in hadrontherapy
A mathematical approach to aspects of LET, micro- and nano-dosimetry in radiation therapy with photons and charged particles
Co ~(60)的辐射效应作为考虑正常和肿瘤组织剂量效应关系中LET和RBE的参考系,通常采用线性二次模型(LQ)处理。这种近似非常适合肩部区域。在粒子治疗中,我们在初始平台和布拉格峰的环境中的RBE之间有严格的区别。因此,对于质子,初始平台的LET和RBE与Co 60一致,而在布拉格峰域中,这两种性质都增加,但SOBP的RBE仅在1.1和1.17之间变化。碳离子的RBE再次增加,由于密集的电离辐射效应,它们的剂量效应曲线更陡,肩域相当小。因此,质子在布拉格峰区域也是密集电离的,但与碳离子相比具有相当小的幅度。基于非线性反应扩散模型,提出了一种推广的LQ模型,用于描述致密电离粒子的LET和RBE,该模型考虑了微米和纳米剂量学的性质。反应扩散公式中的线性项描述了细胞的破坏,非线性项与修复有关,扩散项反映了辐射损伤的密度。根据Co_(60)的剂量-效应特性,可以确定致密电离粒子的参数,并与测量数据进行比较。RBE和剂量效应曲线中辐射效应的局部密集性及其后果提供了理解不同模态的现代治疗计划的关键,并通过数学描述解释了纳米剂量学的性质。球状体的照射是微剂量测定的特征,而细胞内暴露是指纳米剂量测定。
Back with Weight: Revisiting Very Heavy Ions for Precision Radiotherapy
GSI Helmholtzzentrum für Schwerionenforschung(GSI重离子研究中心);University of Santiago de Compostela(圣地亚哥德孔波斯特拉大学);Institut Curie, Université PSL(居里研究所,巴黎文理研究大学);Université Paris-Saclay(巴黎萨克雷大学);Technische Universität Darmstadt(达姆施塔特工业大学);University Federico II(那不勒斯费德里科二世大学)