Technical Note: An efficient daily <scp>QA</scp> procedure for proton pencil beam scanning

Younkin, James E.; Shen, Jiajian; Bues, Martin; Robertson, Daniel; Mundy, Daniel W.; Clouser, Edward; Liu, Wei; Ding, Xiaoning; Stoker, J.

doi:10.1002/mp.12787

Cited by 20 publications

(43 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The larger range uncertainty at high energies is due to the larger distal penumbra caused by range straggling [as shown in Fig. (b)], which is consistent with our daily range QA results …”

Section: Discussionsupporting

confidence: 89%

“…However, the finite proton range, if not precisely controlled, would cause undesirable dosimetric effects, such as underdosing to the target and overdosing to organs at risk . Hence, proton range quality assurance (QA) is one of the most commonly performed QA tasks during routine machine and patient QA …”

Section: Introductionmentioning

confidence: 99%

“…Multilayer ionization chambers (MLIC) are an efficient tool for proton range QA, but their resolution is limited by the intrinsic 1–2 mm chamber spacing . Detectors from a commercial daily QA device have been successfully adapted to measure the sharp distal dose falloff for proton range validations during daily QA . However, this method is limited to verifying only one or two energies.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Technical Note: Using dual step wedge and 2D scintillator to achieve highly precise and robust proton range quality assurance

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…The larger range uncertainty at high energies is due to the larger distal penumbra caused by range straggling [as shown in Fig. (b)], which is consistent with our daily range QA results …”

Section: Discussionsupporting

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Technical Note: Using dual step wedge and 2D scintillator to achieve highly precise and robust proton range quality assurance

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…A variety of detectors and phantoms may be considered for daily QA measurements (Section VI). Which detector or phantom to use depends on the type of measurement to be made . For daily QA checks, phantoms that are easy to set up and reproducible are desirable; for example, a near‐water‐equivalent plastic.…”

Section: Daily Quality Assurance Proceduresmentioning

confidence: 99%

“…Which detector or phantom to use depends on the type of measurement to be made. 91,92 For daily QA checks, phantoms that are easy to set up and reproducible are desirable; for example, a near-water-equivalent plastic. Regardless of the phantom material chosen, the relative linear stopping power (RLSP), the energy dependence of the RLSP, and effects of nuclear interactions should be known.…”

Section: A Beam Dosimetry Parametersmentioning

confidence: 99%

AAPM task group 224: Comprehensive proton therapy machine quality assurance

et al. 2019

View full text Add to dashboard Cite

Purpose: Task Group (TG) 224 was established by the American Association of Physicists in Medicine's Science Council under the Radiation Therapy Committee and Work Group on Particle Beams. The group was charged with developing comprehensive quality assurance (QA) guidelines and recommendations for the three commonly employed proton therapy techniques for beam delivery: scattering, uniform scanning, and pencil beam scanning. This report supplements established QA guidelines for therapy machine performance for other widely used modalities, such as photons and electrons (TG 142, TG 40, TG 24, TG 22, TG 179, and Medical Physics Practice Guideline 2a) and shares their aims of ensuring the safe, accurate, and consistent delivery of radiation therapy dose distributions to patients. Methods: To provide a basis from which machine‐specific QA procedures can be developed, the report first describes the different delivery techniques and highlights the salient components of the related machine hardware. Depending on the particular machine hardware, certain procedures may be more or less important, and each institution should investigate its own situation. Results: In lieu of such investigations, this report identifies common beam parameters that are typically checked, along with the typical frequencies of those checks (daily, weekly, monthly, or annually). The rationale for choosing these checks and their frequencies is briefly described. Short descriptions of suggested tools and procedures for completing some of the periodic QA checks are also presented. Conclusion: Recommended tolerance limits for each of the recommended QA checks are tabulated, and are based on the literature and on consensus data from the clinical proton experience of the task group members. We hope that this and other reports will serve as a reference for clinical physicists wishing either to establish a proton therapy QA program or to evaluate an existing one.

show abstract

Development and long‐term stability of a comprehensive daily QA program for a modern pencil beam scanning (PBS) proton therapy delivery system

Rana

Bennouna

Samuel

et al. 2019

J Applied Clin Med Phys

View full text Add to dashboard Cite

Purpose The main purpose of this study is to demonstrate the clinical implementation of a comprehensive pencil beam scanning (PBS) daily quality assurance (QA) program involving a number of novel QA devices including the Sphinx/Lynx/parallel‐plate (PPC05) ion chamber and HexaCheck/multiple imaging modality isocentricity (MIMI) imaging phantoms. Additionally, the study highlights the importance of testing the connectivity among oncology information system (OIS), beam delivery/imaging systems, and patient position system at a proton center with multi‐vendor equipment and software. Methods For dosimetry, a daily QA plan with spot map of four different energies (106, 145, 172, and 221 MeV) is delivered on the delivery system through the OIS. The delivery assesses the dose output, field homogeneity, beam coincidence, beam energy, width, distal‐fall‐off (DFO), and spot characteristics — for example, position, size, and skewness. As a part of mechanical and imaging QA, a treatment plan with the MIMI phantom serving as the patient is transferred from OIS to imaging system. The HexaCheck/MIMI phantoms are used to assess daily laser accuracy, imaging isocenter accuracy, image registration accuracy, and six‐dimensional (6D) positional correction accuracy for the kV imaging system and robotic couch. Results The daily QA results presented herein are based on 202 daily sets of measurements over a period of 10 months. Total time to perform daily QA tasks at our center is under 30 min. The relative difference (Δrel) of daily measurements with respect to baseline was within ± 1% for field homogeneity, ±0.5 mm for range, width and DFO, ±1 mm for spots positions, ±10% for in‐air spot sigma, ±0.5 spot skewness, and ±1 mm for beam coincidence (except 1 case: Δrel = 1.3 mm). The average Δrel in dose output was −0.2% (range: −1.1% to 1.5%). For 6D IGRT QA, the average absolute difference (Δabs) was ≤0.6 ± 0.4 mm for translational and ≤0.5° for rotational shifts. Conclusion The use of novel QA devices such as the Sphinx in conjunction with the Lynx, PPC05 ion chamber, HexaCheck/MIMI phantoms, and myQA software was shown to provide a comprehensive and efficient method for performing daily QA of a number of system parameters for a modern proton PBS‐dedicated treatment delivery unit.

show abstract

Technical Note: An efficient daily QA procedure for proton pencil beam scanning

Abstract: An efficient daily PBS QA procedure can be performed using a single, nonuniform field on a nondedicated QA device. A thorough quantitation of the device's response and careful control of measurement uncertainties allowed daily tolerances to match commissioning standards.

Cited by 20 publications

References 16 publications

Technical Note: Using dual step wedge and 2D scintillator to achieve highly precise and robust proton range quality assurance

Technical Note: Using dual step wedge and 2D scintillator to achieve highly precise and robust proton range quality assurance

AAPM task group 224: Comprehensive proton therapy machine quality assurance

Development and long‐term stability of a comprehensive daily QA program for a modern pencil beam scanning (PBS) proton therapy delivery system

Contact Info

Product

Resources

About