Design of beam‐modulating devices for charged‐particle therapy

Petti, Paula L.; Lyman, John; Renner, T.; Castro, Joseph R.; Collier, John M.; Daftari, Inder K.; Ludewigt, B.

doi:10.1118/1.596655

Cited by 27 publications

(20 citation statements)

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“…There are, on the other hand, some arguments for using this biological dose in treatment planning because the biological dose is dependent on the type of cell and the survival fraction. That is to say, we have to assume the ideal cell line to determine the biological dose in treatment planning (11,12). In the present study of the SOBP, we did not want to consider the selection of the cell line but rather to consider how to design the SOBP after we selected the cell line.…”

Section: Resultsmentioning

confidence: 99%

“…The irradiation system2 installed at the RIKEN ring cyclotron facility was structurally the same as those installed at NIRS. The range modulator, which is shaped like a propeller form, is composed of sector absorbers of various thicknesses and inserted in the beam course for rotary operation (12,19). The central angle of the each sector is proportional to the weighting factor of the superimposition of the shifted Bragg curve for the SOBP.…”

Section: Range Modulatormentioning

confidence: 99%

“…Usually, the biological response resulting from mixed irradiation with high-and low-LET beams depends not only on the dose-averaged LET of mixed beams but also on the LET spectra of the mixed beams. Petti et al (12) also discussed the design of the SOBP for helium ions. They focused their discussions on the physical part of the beam modulation, that is, how to obtain the planned depth-dose distribution using the beam-modulating devices.…”

Section: Introductionmentioning

confidence: 97%

See 2 more Smart Citations

Irradiation of Mixed Beam and Design of Spread-Out Bragg Peak for Heavy-Ion Radiotherapy

Kanai¹,

Furusawa²,

Fukutsu³

et al. 1997

Radiation Research

384

280

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Data on cellular inactivation resulting from mixed irradiation with charged-particle beams of different linear energy transfer (LET) are needed to design a spread-out Bragg peak (SOBP) for heavy-ion radiotherapy. The present study was designed to study the relationship between the physical (LET) and biological (cell killing) properties by using different monoenergetic beams of 3He, 4He and 12C ions (12 and 18.5 MeV/nucleon) and to attempt to apply the experimental data in the design of the SOBP (3 cm width) with a 135 MeV/nucleon carbon beam. Experimental studies of the physical and biological measurements using sequentially combined irradiation were carried out to establish a close relationship between LET and cell inactivation. The results indicated that the dose-cell survival relationship for the combined high- and low-LET beams could be described by a linear-quadratic (LQ) model, in which new coefficients alpha and beta for the combined irradiation were obtained in terms of dose-averaged alpha and square root of beta for the single irradiation with monoenergetic beams. Based on the relationship obtained, the actual SOBP designed for giving a uniform biological effect at 3 cm depth was tested with the 135 MeV/nucleon carbon beam. The results of measurements of both physical (LET) and biological (90% level of cell killing, etc.) properties clearly demonstrated that the SOBP successfully and satisfactorily retained its high dose localization and uniform depth distribution of the biological effect. Based on the application of these results, more useful refinement and development can be expected for the heavy-ion radiotherapy currently under way at the National Institute of Radiological Sciences, Japan.

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Section: Resultsmentioning

confidence: 99%

Section: Range Modulatormentioning

confidence: 99%

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

Irradiation of Mixed Beam and Design of Spread-Out Bragg Peak for Heavy-Ion Radiotherapy

Kanai¹,

Furusawa²,

Fukutsu³

et al. 1997

Radiation Research

384

280

View full text Add to dashboard Cite

show abstract

“…These can then be used, as discussed below, to create a spread-out Bragg peak that gives the desired (usually uniform) cell survival distribution over the target volume. 293 In the absence of fragmentation with only the primary beam particles contributing significantly to the cell killing, the beam weights can be found by the following procedure. The dose at di in a SOBP is the sum of the doses of the individual Bragg ionization curves at di, …”

Section: Iib Range Modulationmentioning

confidence: 99%

Instrumentation for treatment of cancer using proton and light-ion beams

Chu

Ludewigt

Renner

1993

Review of Scientific Instruments

Self Cite

285

186

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Clinical trials using accelerated heavy charged-particle beams for treating cancer and other diseases have been performed for nearly four decades. Recently there have been worldwide efforts to construct hospital-based medically dedicated proton or light-ion accelerator facilities. To make such accelerated heavy charged-particle beams clinically useful, specialized instruments must be developed to modify the physical characteristics of the particle beams in order to optimize their biological and clinical effects. This article reviews the beam modifying devices and associated dosimetric equipment developed specifically for controlling and monitoring the clinical beams.

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“…The secondary emission monitor (SEM) [17] A range modulator [20] made from Lucite is located just after IC1. It is followed by a variable water column, which permits measurements to be made at various depths of penetration [21] …”

Section: Beam Monitoring and Dosimetry Systemmentioning

confidence: 99%

Proton Beam Ocular Treatment in Eyes with Intraocular Silicone Oil: Effects on Physical Beam Parameters and Clinical Relevance of Silicone Oil in EYEPLAN Dose-Volume Histograms

Daftari¹,

Mishra²,

Seider³

et al. 2018

IJMPCERO

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Proton beam therapy (PBRT) is an essential tool in the treatment of certain ocular tumors due to its characteristic fall-off and sharp beam parameters at critical structures. Review of clinical cases in our ocular PBRT program identified patients with silicone oil used as an intraocular tamponade following pars plana vitrectomy for repair of retinal detachment. Patient's eye may be filled with silicone oil prior to PBRT for an ocular tumor. The objective of this study was to extend our knowledge of the physical characteristics of proton beams in silicone oil by measuring dose within a silicone tank itself, hence better representing the surgical eye, as well as applying the range changes to EYEPLAN software to estimate clinical impact. The relevant proton beam physical parameters in silicone oil were studied using a 67.5 MeV un-modulated proton beam. The beam parameters being defined included: 1) residual range; 2) peak/plateau ratio; 3) full width at half maximum (FWHM) of the Bragg peak; and 4) distal penumbra. Initially, the dose uniformity of the proton beam was confirmed at 10 mm and 28 mm depth, corresponding to plateau and peak region of the Bragg peak using Gefchromic film. Once the beam was established as expected, three sets of measurements of the beam parameters were taken in: a) water (control); b) silicone-1000 oil and water; and c) silicone-1000 oil only. Central-axis depth-ionization measurements were performed in a tank ("main tank") with a 0.1cc ionization chamber (Model IC-18, Far west) having walls made of Shonka A150 plastic. The tank was 92 mm (length) × 40 mm (height) × 40 mm (depth). The tank had a 0.13 mm thick kapton entrance window through which the proton beam was incident. The ionization chamber was always positioned in the center of the circular field of diameter 30 mm with the phantom surface at isocenter. The ionization chamber measurements were taken at defined depths in increments of 2 mm, from 0 to 35 mm. To define the effect of silicone oil on the physical characteristics of proton beam, the above-defined three sets of measurements were made. In the first run (a), the Bragg-peak measurements were made in the main tank filled with water. In the second run (b), a second smaller tank filled with 10 mm depth silicone oil was placed in front of the water tank and the measurements were repeated in water. In the third run (c), the water in the main tank was replaced with silicone oil and the measurements were repeated in silicone directly (no second tank in runs "a" and "c"). Finally, the effects of change in range on dose distribution based on the EYEPLAN® treatment planning software of patients with lesions in close proximity to the disc/macula as well as ciliary body tumors were studied. The uniformity of the radiation across the treatment volume shows that the radiation field was uniform within ± 3% at 10 mm depth and within ±4% at 28 mm depth. Parameters evaluated for the three runs (a, b, c) included: 1) residual range; 2) peak/plateau ratio; 3) FWHM of the Bragg curve; a...

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Design of beam‐modulating devices for charged‐particle therapy

Cited by 27 publications

References 0 publications

Irradiation of Mixed Beam and Design of Spread-Out Bragg Peak for Heavy-Ion Radiotherapy

Irradiation of Mixed Beam and Design of Spread-Out Bragg Peak for Heavy-Ion Radiotherapy

Instrumentation for treatment of cancer using proton and light-ion beams

Proton Beam Ocular Treatment in Eyes with Intraocular Silicone Oil: Effects on Physical Beam Parameters and Clinical Relevance of Silicone Oil in EYEPLAN Dose-Volume Histograms

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