Identification of Induced Radionuclides Produced from Dental Metals in Proton Beam Therapy for Head and Neck Cancer

Kato, Ryohei; Katō, Takahiro; Narita, Yuki; Sasaki, Shinya; Takayama, Kohei; Murakami, Masao

doi:10.1016/j.adro.2022.101153

Cited by 3 publications

(8 citation statements)

References 28 publications

(34 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using the same cooling time, the detected radionuclides in the present study were in agreement with the above findings, except for a few isotopes. In our previous work, we identified radionuclides generated from titanium cylinder using a150-MeV passive scattering beam with a 60-mm SOBP [17]. Although the representative proton energy was different from that obtained in the present study, the radionuclides with relatively high activity were basically consistent in both the studies.…”

Section: Relative Activitycontrasting

confidence: 45%

“…A cross-section of (p, x) reaction in an arbitrary material typically changes depending on the proton energy. A previous study investigated the radioactivation of dental metals using a 150-MeV passive scattering proton beam for a patient with head and neck cancer [17], whereas clinical proton beams include higher energy protons. However, proton beam energy may affect the radioactivation of metals.…”

Section: Evaluation Of Proton Energy Dependence Produced Radionuclide...mentioning

confidence: 99%

“…With regard to the metal radioactivation in PBT, Bäcker et al identified the radionuclides produced from titanium by measurements, and showed their reaction cross sections [10]. Furthermore, our previous study identified radionuclides produced from dental metals and the feasibility of the Monte Carlo (MC) simulation using a low energy clinical proton beam [17]. An activation cross section of (p, x) reaction in an arbitrary material typically changes depending on the proton energy.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Radioactivation effects of titanium caused by clinical proton beam: a simulation study

Kato,

Murakami

2024

Biomed. Phys. Eng. Express

Self Cite

View full text Add to dashboard Cite

Objective. In proton beam therapy (PBT), metals in the patient body perturb the dose distribution, and their radioactivation may affect the dose distribution around the metal; however, the radioactivation effect has been not clarified with PBT. In this study, we aimed to evaluate the radioactivation effect of metal depending on proton energies and secondary neutrons with a clinical proton beam using a Monte Carlo (MC) simulation.Approach. The radionuclides produced from a titanium alloy (Ti-6Al-4V) and their radioactivity were calculated using a 210-MeV passive scattering proton beam with a 60-mm Spread-out Bragg Peak, and the deposited doses caused by the radioactivation were computed using the MC simulation. The position of metal was changed according to the proton mean energy in water. To assess neutron effects on the radioactivation, we calculated the radioactivation in following three situations: (i) full MC simulation with neutrons, (ii) simulation without secondary neutrons generated from the beamline components, and (iii) simulation without any secondary neutrons.Main results. Immediately after the irradiation, the radionuclide with the largest activity was Sc-45 m (half-life of 318 ms) regardless of the proton energy and the presence of neutrons. Total radioactivity tended to increase according to the proton energy. The accumulated dose for 24 h caused by the metal activation showed an increasing trend with the proton energy, with a maximum increase rate of 0.045% to the prescribed dose. The accumulated dose at a distance of 10 mm from the metal was lower than 1/10 of that at a distance of 1 mm.Significance. The radioactivation effect of the titanium was comprehensively evaluated in the clinical passive scattering proton beam. We expect that radioactivation effects on the clinical dose distribution would be small. We consider that these results will help the clinical handling of high-Z metals in PBT.

show abstract

Section: Relative Activitycontrasting

confidence: 45%

Section: Evaluation Of Proton Energy Dependence Produced Radionuclide...mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Radioactivation effects of titanium caused by clinical proton beam: a simulation study

Kato,

Murakami

2024

Biomed. Phys. Eng. Express

Self Cite

View full text Add to dashboard Cite

show abstract

“…We appreciate the letter by Bäcker et al who suggested strategies for improving the reliability of the database of activation cross-sections. As we pointed out in our discussion, 1 nuclear reaction models in a Monte Carlo (MC) simulation exhibit certain uncertainties. 2 Therefore, the determination of an activation cross-section based on actual measurements is justified, and we consider this important for improving the accuracy of MC simulations.…”

mentioning

confidence: 93%

“…Moreover, we reported a novel observation that the activity of gold-silver-palladium alloys is higher than that of titanium. 1 However, as mentioned previously, these results require careful interpretation because uncertainties of both the MC simulations and measurements. One of our objectives was also to evaluate the usefulness of Particle and Heavy Ion Transport code System as a tool for pre-estimating the types of radionuclides in proton beam therapy.…”

mentioning

confidence: 95%