PMID- 32268309
OWN - NLM
STAT- MEDLINE
DCOM- 20201030
LR  - 20201030
IS  - 1361-6560 (Electronic)
IS  - 0031-9155 (Linking)
VI  - 65
IP  - 15
DP  - 2020 Jul 27
TI  - Experimental comparison of clinically used ion beams for imaging applications 
      using a range telescope.
PG  - 155004
LID - 10.1088/1361-6560/ab87f6 [doi]
AB  - In particle therapy, the x-ray based treatment planning converting photon 
      attenuation values to relative stopping power ratio (RSP) introduces clinically 
      relevant range uncertainties. Recently, novel imaging technologies using 
      transmission ion beams have been investigated to directly assess the water 
      equivalent thickness (WET) of tissue, showing improved accuracy in RSP 
      reconstruction, while potentially reducing the imaging dose. Due to their greater 
      availability, protons have been mostly used for ion imaging. To this end, in this 
      work, the influence of three ion species (protons, helium and carbon ions) on the 
      image quality of radiographic WET retrieval has been explored with a dedicated 
      experimental setup and compared to Monte Carlo (MC) simulations. Three phantom 
      setups with different tissue interfaces and features have been irradiated with 
      clinically validated proton, helium and carbon ion pencil beams under comparable 
      imaging dose and beam settings at the Heidelberg Ion-Beam Therapy Center. Ion 
      radiographies (iRADs) were acquired with an integration mode detector, that 
      functions as a range telescope with 61 parallel plate ionization chambers. For 
      comparison, experiments were reproduced in-silico with FLUKA MC simulations. 
      Carbon ions provide iRADs with highest image quality in terms of normalized root 
      mean square error, followed by helium ions and protons. All ions show similar 
      capabilities of resolving WET for the considered phantoms, as shown by the 
      similar average relative error < 3%. Besides for the slab phantom, MC simulations 
      yielded better results than the experiment, indicating potential improvement of 
      the experimental setup. Our results showed that the ability to resolve the WET is 
      similar for all particles, intrinsically limited by the granularity of the 
      detector system. While carbon ions are best suited for acquiring iRADs with the 
      investigated integration mode detector, helium ions are put forward as a less 
      technical challenging alternative.
FAU - Kopp, Benedikt
AU  - Kopp B
AD  - Ludwig-Maximilians-Universitat Munchen, Department of Experimental Physics, 
      Munich, Germany. Current address: Clinical Cooperation Unit Translational 
      Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg 
      University Hospital (UKHD) and German Cancer Research Center (DKFZ), Heidelberg, 
      Germany. Current address: Division of Molecular and Translational Radiation 
      Oncology, Department of Radiation Oncology, Heidelberg Faculty of Medicine (MFHD) 
      and Heidelberg University Hospital (UKHD), Heidelberg Ion-Beam Therapy Center 
      (HIT), Heidelberg, Germany. Current address: German Cancer Consortium (DKTK) 
      Core-Center Heidelberg, German Cancer Research Center (DKFZ), Heidelberg, 
      Germany. Current address: Clinical Cooperation Unit Radiation Oncology, 
      Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation 
      Oncology (NCRO), Heidelberg University and German Cancer Research Center (DKFZ), 
      Heidelberg, Germany. Current address: Department of Physics and Astronomy, 
      Heidelberg University, Heidelberg, Germany.
FAU - Meyer, Sebastian
AU  - Meyer S
FAU - Gianoli, Chiara
AU  - Gianoli C
FAU - Magallanes, Lorena
AU  - Magallanes L
FAU - Voss, Bernd
AU  - Voss B
FAU - Brons, Stephan
AU  - Brons S
FAU - Parodi, Katia
AU  - Parodi K
LA  - eng
PT  - Comparative Study
PT  - Journal Article
DEP - 20200727
PL  - England
TA  - Phys Med Biol
JT  - Physics in medicine and biology
JID - 0401220
RN  - 0 (Protons)
RN  - 059QF0KO0R (Water)
RN  - 206GF3GB41 (Helium)
RN  - 7440-44-0 (Carbon)
SB  - IM
MH  - Carbon
MH  - Helium
MH  - Humans
MH  - Monte Carlo Method
MH  - Phantoms, Imaging
MH  - Protons
MH  - Radiography/*instrumentation
MH  - Radiometry
MH  - *Telescopes
MH  - Water
EDAT- 2020/04/09 06:00
MHDA- 2020/10/31 06:00
CRDT- 2020/04/09 06:00
PHST- 2020/04/09 06:00 [pubmed]
PHST- 2020/10/31 06:00 [medline]
PHST- 2020/04/09 06:00 [entrez]
AID - 10.1088/1361-6560/ab87f6 [doi]
PST - epublish
SO  - Phys Med Biol. 2020 Jul 27;65(15):155004. doi: 10.1088/1361-6560/ab87f6.