Energy loss of 70 MeV protons in elements

Bischel, Hans; Hiraoka, Takeshi

doi:10.1016/0168-583x(92)95995-4

Cited by 75 publications

(47 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The uncertainties we quote here are the combined uncertainties from CT imaging and calibration and I ‐values. The uncertainty on the I ‐value was determined in earlier studies by Bichsel and Hiraoka and Kumazaki et al., quoting a contribution on range uncertainty of 1.5% . Our results however suggest that this number is overestimated, especially in soft tissues.…”

Section: Discussioncontrasting

confidence: 40%

See 1 more Smart Citation

Experimental validation of two dual‐energy CT methods for proton therapy using heterogeneous tissue samples

et al. 2017

View full text Add to dashboard Cite

The present work uses experimental measurements in a realistic clinical environment to show potential benefits of DECT for proton therapy treatment planning. Our results show clear improvements over SECT in tissue-equivalent plastic materials and animal tissues. Further work towards using Monte Carlo simulations for treatment planning with DECT data and a more detailed investigation of the uncertainties on I-value and limitations on the Bragg additivity rule could potentially further enhance the benefits of this imaging technology for proton therapy.

show abstract

Section: Discussioncontrasting

confidence: 40%

“…The contribution of the I ‐value uncertainty

u_{I}

to range uncertainty was estimated previously . In this study, we expect to observe a combined uncertainty of the contributions from I ‐value and CT calibration and conversion, defined as

u_{normalcomb}^{2} = u_{I}^{2} + u_{normalCT}^{2} .

…”

Section: Methodsmentioning

confidence: 62%

Experimental validation of two dual‐energy CT methods for proton therapy using heterogeneous tissue samples

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The S 1 and S 2 sum rules are fulfilled within 0.5 %. The mean excitation energy is calculated to be I = 78.30 eV, which is close to the experimental value I = 79.75 eV of Bichsel and Hiraoka (1992) and I = 77.8 eV of other model calculations (Emfietzoglou et al, 2009), but higher than the currently recommended ICRU value I = 75.00 eV (ICRU Report 49, 1993). Total I values for different maximum energy transfers (10 eV to 100 keV) and contributions from the valence shells only (outer shell ionisations and excitations) are shown in Figure 1.…”

Section: The Updated Model For the Dielectric Response Function Ofsupporting

confidence: 76%

Updated model for dielectric response function of liquid water

Dingfelder¹

2014

Applied Radiation and Isotopes

View full text Add to dashboard Cite

show abstract

“…Even for water, several different values have been suggested in the literature: 67 eV, 75 eV, 78 eV, and 80 eV (ICRU, 2005; Paul et al , 2007; ICRU, 1993; Kumazaki et al , 2007; Emfietzoglou et al , 2009; Bischel and Hiraoka, 1992; Andreo, 2009). The uncertainty in the mean excitation energy of water yields up to 1% uncertainty in the calculated stopping power.…”

Section: Methodsmentioning

confidence: 99%

Comprehensive analysis of proton range uncertainties related to patient stopping-power-ratio estimation using the stoichiometric calibration

Yang¹,

Zhu²,

Park³

et al. 2012

Phys. Med. Biol.

314

396

View full text Add to dashboard Cite

The purpose of this study was to analyze factors affecting proton stopping-power-ratio (SPR) estimations and range uncertainties in proton therapy planning using the standard stoichiometric calibration. The SPR uncertainties were grouped into five categories according to their origins and then estimated based on previously published reports or measurements. For the first time, the impact of tissue composition variations on SPR estimation was assessed and the uncertainty estimates of each category were determined for low-density (lung), soft, and high-density (bone) tissues. A composite, 95th percentile water-equivalent-thickness uncertainty was calculated from multiple beam directions in 15 patients with various types of cancer undergoing proton therapy. The SPR uncertainties (1σ) were quite different (ranging from 1.6% to 5.0%) in different tissue groups, although the final combined uncertainty (95th percentile) for different treatment sites was fairly consistent at 3.0–3.4%, primarily because soft tissue is the dominant tissue type in human body. The dominant contributing factor for uncertainties in soft tissues was the degeneracy of Hounsfield Numbers in the presence of tissue composition variations. To reduce the overall uncertainties in SPR estimation, the use of dual-energy computed tomography is suggested. The values recommended in this study based on typical treatment sites and a small group of patients roughly agree with the commonly referenced value (3.5%) used for margin design. By using tissue-specific range uncertainties, one could estimate the beam-specific range margin by accounting for different types and amounts of tissues along a beam, which may allow for customization of range uncertainty for each beam direction.

show abstract

Energy loss of 70 MeV protons in elements

Cited by 75 publications

References 9 publications

Experimental validation of two dual‐energy CT methods for proton therapy using heterogeneous tissue samples

Experimental validation of two dual‐energy CT methods for proton therapy using heterogeneous tissue samples

Updated model for dielectric response function of liquid water

Comprehensive analysis of proton range uncertainties related to patient stopping-power-ratio estimation using the stoichiometric calibration

Contact Info

Product

Resources

About