Characterization of the Plastic Scintillator Detector System Exradin W2 in a High Dose Rate Flattening-Filter-Free Photon Beam

Thrower, Sara L.; Prajapati, Surendra; Holmes, S; Schüler, Emil; Beddar, Sam

doi:10.3390/s22186785

Cited by 3 publications

(14 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The W2 has been examined in previous studies demonstrating its acceptability for real-time dose monitoring in conventional dose-rate beamlines, but its use has not been evaluated in UHDR and ultra-high DPP electron beamlines. 31,33,34 Previous work by Ashraf et al 45 and Poirier et al 46 evaluated plastic scintillators' response in UHDR electron beamlines, but only for DPP and mean dose rate settings below 1.1 Gy per pulse and at dose rates less than 400 Gy/s, respectively. Our study adds to this previous research by exploring the response of the W2 at dose, DPP, and dose-rate ranges exceeding 100 Gy, 9 Gy per pulse, and 1000 Gy/s, respectively.…”

Section: Discussionmentioning

confidence: 99%

“…The observed changes in sensitivity of the W2 under UHDR electron conditions are more in line with those reported for plastic scintillators irradiated in conventional beamlines (<1%-2% per kGy). 31,32,35 In this study, radiation damage over a single day was evaluated with a mix of dose rates and DPP values, making it difficult to quantify and isolate doserate and DPP effects or scintillator recovery over time. Therefore, the signal decrease presented here should be seen as a "worst case scenario" because the W2 in this study was irradiated with up to 8.5 kGy in a single day under mixed UHDR beam conditions.…”

Section: Discussionmentioning

confidence: 99%

“…The W2-1 × 1 fiber has a scintillator diameter of 1.0 mm and length of 1.0 mm, with a physical density of 1.05 g/cm 3 . 31 The W2-1 × 3 is identical except for its scintillator length, which is 3.0 mm. For this investigation, only the W2-1 × 1 geometry was used.…”

Section: W2 Systemmentioning

confidence: 99%

“…[28][29][30] In addition, PSDs have been established by multiple investigators to be linear with dose and independent of dose rate at clinically relevant dose rates. 28,29,[31][32][33][34][35] However, no comprehensive evaluation of PSDs at the extended doses, dose rates, and DPP values (>10 Gy, >100 Gy/s, >1.5 Gy/pulse, respectively) used in the first FLASH-RT clinical trials, 4,36 has yet been conducted. These dose rates and DPP values are of particular interest because several studies investigating the FLASH effect report enhanced normal tissue sparing under dose-rate and DPP conditions that far exceed 100 Gy/s and 1 Gy, respectively.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A comprehensive investigation of the performance of a commercial scintillator system for applications in electron FLASH radiotherapy

Liu,

Holmes,

Schüler

et al. 2024

Medical Physics

Self Cite

View full text Add to dashboard Cite

BackgroundDosimetry in ultra‐high dose rate (UHDR) beamlines is significantly challenged by limitations in real‐time monitoring and accurate measurement of beam output, beam parameters, and delivered doses using conventional radiation detectors, which exhibit dependencies in ultra‐high dose‐rate (UHDR) and high dose‐per‐pulse (DPP) beamline conditions.PurposeIn this study, we characterized the response of the Exradin W2 plastic scintillator (Standard Imaging, Inc.), a water‐equivalent detector that provides measurements with a time resolution of 100 Hz, to determine its feasibility for use in UHDR electron beamlines.MethodsThe W2 scintillator was exposed to an UHDR electron beam with different beam parameters by varying the pulse repetition frequency (PRF), pulse width (PW), and pulse amplitude settings of an electron UHDR linear accelerator system. The response of the W2 scintillator was evaluated as a function of the total integrated dose delivered, DPP, and mean and instantaneous dose rate. To account for detector radiation damage, the signal sensitivity (pC/Gy) of the W2 scintillator was measured and tracked as a function of dose history.ResultsThe W2 scintillator demonstrated mean dose rate independence and linearity as a function of integrated dose and DPP for DPP ≤ 1.5 Gy (R2 > 0.99) and PRF ≤ 90 Hz. At DPP > 1.5 Gy, nonlinear behavior and signal saturation in the blue and green signals as a function of DPP, PRF, and integrated dose became apparent. In the absence of Cerenkov correction, the W2 scintillator exhibited PW dependence, even at DPP values <1.5 Gy, with a difference of up to 31% and 54% in the measured blue and green signal for PWs ranging from 0.5 to 3.6 µs. The change in signal sensitivity of the W2 scintillator as a function of accumulated dose was approximately 4%/kGy and 0.3%/kGy for the measured blue and green signal responses, respectively, as a function of integrated dose history.ConclusionThe Exradin W2 scintillator can provide output measurements that are both dose rate independent and linear in response if the DPP is kept ≤1.5 Gy (corresponding to a mean dose rate up to 290 Gy/s in the used system), as long as proper calibration is performed to account for PW and changes in signal sensitivity as a function of accumulated dose. For DPP > 1.5 Gy, the W2 scintillator's response becomes nonlinear, likely due to limitations in the electrometer related to the high signal intensity.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: W2 Systemmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A comprehensive investigation of the performance of a commercial scintillator system for applications in electron FLASH radiotherapy

Liu,

Holmes,

Schüler

et al. 2024

Medical Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition, six different types of detectors (summarized in Table 1) were used to determine the relative output factors including a microSilicon diode, microDiamond detector, W2 plastic scintillator, A16 and A1SL ionization chambers, and alanine dosimeters. [30][31][32][33][34][35][36][37][38][39][40] The PTW 60023 microSilicon diode (PTW Dosimetry, Freiburg, Germany) is an unshielded, p-type silicon diode designed to yield high-dose stability, low dose per pulse dependence, and limited sensitivity to temperature variations (usually ≤ 0.1 %/K). 31 The active volume is 0.03 mm 3 with a radius of 0.75 mm and thickness of 18 µm, whereas total dimensions are 7 mm (diameter) and 45.5 mm (length).…”

Section: Radiation Detectorsmentioning

confidence: 99%

Accurate machine‐specific reference and small‐field dosimetry for a self‐shielded neuro‐radiosurgical system

Jermain,

Muir,

McEwen

et al. 2024

Medical Physics

View full text Add to dashboard Cite

BackgroundThe newly available ZAP‐X stereotactic radiosurgical system is designed for the treatment of intracranial lesions, with several unique features that include a self‐shielding, gyroscopic gantry, wheel collimation, non‐orthogonal kV imaging, short source‐axis distance, and low‐energy megavoltage beam. Systematic characterization of its radiation as well as other properties is imperative to ensure its safe and effective clinical application.PurposeTo accurately determine the radiation output of the ZAP‐X with a special focus on the smaller diameter cones and an aim to provide useful recommendations on quantification of small field dosimetry.MethodsSix different types of detectors were used to measure relative output factors at field sizes ranging from 4 to 25 mm, including the PTW microSilicon and microdiamond diodes, Exradin W2 plastic scintillator, Exradin A16 and A1SL ionization chambers, and the alanine dosimeter. The 25 mm cone served as the reference field size. Absolute dose was determined with both TG‐51‐based dosimetry using a calibrated PTW Semiflex ion chamber and measurements using alanine dosimeters.ResultsThe average radiation output factors (maximum deviation from the average) measured with the microDiamond, microSilicon, and W2 detectors were: for the 4 mm cone, 0.741 (1.0%); for the 5 mm cone: 0.817 (1.0%); for the 7.5 mm cone: 0.908 (1.0%); for the 10 mm cone: 0.946 (0.4%); for the 12.5 mm cone: 0.964 (0.2%); for the 15 mm cone: 0.976 (0.1%); for the 20 mm cone: 0.990 (0.1%). For field sizes larger than 10 mm, the A1SL and A16 micro‐chambers also yielded consistent output factors within 1.5% of those obtained using the microSilicon, microdiamond, and W2 detectors. The absolute dose measurement obtained with alanine was within 1.2%, consistent with combined uncertainties, compared to the PTW Semiflex chamber for the 25 mm reference cone.ConclusionFor field sizes less than 10 mm, the microSilicon diode, microDiamond detector, and W2 scintillator are suitable devices for accurate small field dosimetry of the ZAP‐X system. For larger fields, the A1SL and A16 micro‐chambers can also be used. Furthermore, alanine dosimetry can be an accurate verification of reference and absolute dose typically measured with ion chambers. Use of multiple suitable detectors and uncertainty analyses were recommended for reliable determination of small field radiation outputs.

show abstract

Validation of a New Scintillating Fiber Dosimeter for Radiation Dose Quality Control in Computed Tomography

Guillochon¹,

Balde²,

Popotte

et al. 2023

Sensors

View full text Add to dashboard Cite

(1) Background: The IVIscan is a commercially available scintillating fiber detector designed for quality assurance and in vivo dosimetry in computed tomography (CT). In this work, we investigated the performance of the IVIscan scintillator and associated method in a wide range of beam width from three CT manufacturers and compared it to a CT chamber designed for Computed Tomography Dose Index (CTDI) measurements. (2) Methods: We measured weighted CTDI (CTDIw) with each detector in accordance with the requirements of regulatory tests and international recommendations for the minimum, maximum and the most used beam width in clinic and investigated the accuracy of the IVIscan system based on the assessment of the CTDIw deviation from the CT chamber. We also investigated the IVIscan accuracy for the whole range of the CT scans kV. (3) Results: We found excellent agreement between the IVIscan scintillator and the CT chamber for the whole range of beam widths and kV, especially for wide beams used on recent technology of CT scans. (4) Conclusions: These findings highlight that the IVIscan scintillator is a relevant detector for CT radiation dose assessments, and the method associated with calculating the CTDIw saves a significant amount of time and effort when performing tests, especially with regard to new CT technologies.

show abstract

Characterization of the Plastic Scintillator Detector System Exradin W2 in a High Dose Rate Flattening-Filter-Free Photon Beam

Cited by 3 publications

References 24 publications

A comprehensive investigation of the performance of a commercial scintillator system for applications in electron FLASH radiotherapy

A comprehensive investigation of the performance of a commercial scintillator system for applications in electron FLASH radiotherapy

Accurate machine‐specific reference and small‐field dosimetry for a self‐shielded neuro‐radiosurgical system

Validation of a New Scintillating Fiber Dosimeter for Radiation Dose Quality Control in Computed Tomography

Contact Info

Product

Resources

About