1
|
Debnath SBC, Fauquet C, Tallet A, Goncalves A, Lavandier S, Jandard F, Tonneau D, Darreon J. High spatial resolution inorganic scintillator detector for high-energy X-ray beam at small field irradiation. Med Phys 2020; 47:1364-1371. [PMID: 31883388 PMCID: PMC7155062 DOI: 10.1002/mp.14002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/03/2019] [Accepted: 12/18/2019] [Indexed: 12/12/2022] Open
Abstract
Purpose Small field dosimetry for radiotherapy is one of the major challenges due to the size of most dosimeters, for example, sufficient spatial resolution, accurate dose distribution and energy dependency of the detector. In this context, the purpose of this research is to develop a small size scintillating detector targeting small field dosimetry and compare its performance with other commercial detectors. Method An inorganic scintillator detector (ISD) of about 200 µm outer diameter was developed and tested through different small field dosimetric characterizations under high‐energy photons (6 and 15 MV) delivered by an Elekta Linear Accelerator (LINAC). Percentage depth dose (PDD) and beam profile measurements were compared using dosimeters from PTW namely, microdiamond and PinPoint three‐dimensional (PP3D) detector. A background fiber method has been considered to quantitate and eliminate the minimal Cerenkov effect from the total optical signal magnitude. Measurements were performed inside a water phantom under IAEA Technical Reports Series recommendations (IAEA TRS 381 and TRS 483). Results Small fields ranging from 3 × 3 cm2, down to 0.5 × 0.5 cm2 were sequentially measured using the ISD and commercial dosimeters, and a good agreement was obtained among all measurements. The result also shows that, scintillating detector has good repeatability and reproducibility of the output signal with maximum deviation of 0.26% and 0.5% respectively. The Full Width Half Maximum (FWHM) was measured 0.55 cm for the smallest available square size field of 0.5 × 0.5 cm2, where the discrepancy of 0.05 cm is due to the scattering effects inside the water and convolution effect between field and detector geometries. Percentage depth dose factor dependence variation with water depth exhibits nearly the same behavior for all tested detectors. The ISD allows to perform dose measurements at a very high accuracy from low (50 cGy/min) to high dose rates (800 cGy/min) and was found to be independent of dose rate variation. The detection system also showed an excellent linearity with dose; hence, calibration was easily achieved. Conclusions The developed detector can be used to accurately measure the delivered dose at small fields during the treatment of small volume tumors. The author's measurement shows that despite using a nonwater‐equivalent detector, the detector can be a powerful candidate for beam characterization and quality assurance in, for example, radiosurgery, Intensity‐Modulated Radiotherapy (IMRT), and brachytherapy. Our detector can provide real‐time dose measurement and good spatial resolution with immediate readout, simplicity, flexibility, and robustness.
Collapse
Affiliation(s)
| | - Carole Fauquet
- Aix Marseille Université, CNRS, CINaM, UMR 7325, 13288, Marseille, France
| | - Agnes Tallet
- Institut Paoli-Calmettes, 13009, Marseille, France
| | - Anthony Goncalves
- Aix Marseille Université, CNRS, UMR 7258, INSERM, UMR 1068, CRCM, 13009, Marseille, France
| | | | - Franck Jandard
- Aix Marseille Université, CNRS, CINaM, UMR 7325, 13288, Marseille, France
| | - Didier Tonneau
- Aix Marseille Université, CNRS, CINaM, UMR 7325, 13288, Marseille, France
| | | |
Collapse
|
2
|
Souza S, d'Errico F, Azimi B, Baldassare A, Alves A, Valença J, Barros V, Cascone M, Lazzeri L. OSL films for in-vivo entrance dose measurements. RADIAT MEAS 2017. [DOI: 10.1016/j.radmeas.2017.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
4
|
Yoo WJ, Shin SH, Jeon D, Hong S, Sim HI, Kim SG, Jang KW, Cho S, Youn WS, Lee B. Measurement of entrance surface dose on an anthropomorphic thorax phantom using a miniature fiber-optic dosimeter. SENSORS (BASEL, SWITZERLAND) 2014; 14:6305-16. [PMID: 24694678 PMCID: PMC4029715 DOI: 10.3390/s140406305] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 03/26/2014] [Accepted: 03/27/2014] [Indexed: 11/16/2022]
Abstract
A miniature fiber-optic dosimeter (FOD) system was fabricated using a plastic scintillating fiber, a plastic optical fiber, and a multi-pixel photon counter to measure real-time entrance surface dose (ESD) during radiation diagnosis. Under varying exposure parameters of a digital radiography (DR) system, we measured the scintillating light related to the ESD using the sensing probe of the FOD, which was placed at the center of the beam field on an anthropomorphic thorax phantom. Also, we obtained DR images using a flat panel detector of the DR system to evaluate the effects of the dosimeter on image artifacts during posteroanterior (PA) chest radiography. From the experimental results, the scintillation output signals of the FOD were similar to the ESDs including backscatter simultaneously obtained using a semiconductor dosimeter. We demonstrated that the proposed miniature FOD can be used to measure real-time ESDs with minimization of DR image artifacts in the X-ray energy range of diagnostic radiology.
Collapse
Affiliation(s)
- Wook Jae Yoo
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Sang Hun Shin
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Dayeong Jeon
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Seunghan Hong
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Hyeok In Sim
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Seon Geun Kim
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Kyoung Won Jang
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| | - Seunghyun Cho
- Department of Organic Materials & Fiber Engineering, College of Engineering, Soongsil University, 369 Sangdo-ro, Dongjak-gu, Seoul-si, 156-743, Korea.
| | - Won Sik Youn
- Research & Development Center, JPI Healthcare, Osongsaengmyeong 1-ro, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, 363-951, Korea.
| | - Bongsoo Lee
- School of Biomedical Engineering, College of Biomedical & Health Science, Research Institute of Biomedical Engineering, Konkuk University, 268 Chungwon-daero, Chungju-si, Chungcheongbuk-do, 380-701, Korea.
| |
Collapse
|
5
|
Yoo WJ, Shin SH, Jeon D, Hong S, Kim SG, Sim HI, Jang KW, Cho S, Lee B. Simultaneous measurements of pure scintillation and Cerenkov signals in an integrated fiber-optic dosimeter for electron beam therapy dosimetry. OPTICS EXPRESS 2013; 21:27770-27779. [PMID: 24514292 DOI: 10.1364/oe.21.027770] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
For real-time dosimetry in electron beam therapy, an integrated fiber-optic dosimeter (FOD) is developed using a water-equivalent dosimeter probe, four transmitting optical fibers, and a multichannel light-measuring device. The dosimeter probe is composed of two inner sensors, a scintillation sensor and a Cerenkov sensor, and each sensor has two different channels. Accordingly, we measured four separate light signals from each channel in the dosimeter probe, simultaneously, and then obtained the scintillation and Cerenkov signals using a subtraction method. To evaluate the performance of the integrated FOD, we measured the light signals according to the irradiation angle of the electron beam, the depth variation of the solid water phantom, and the electron beam energy. In conclusion, we demonstrated that the pure scintillation and Cerenkov signals obtained by an integrated FOD system based on a subtraction method can be effectively used for calibrating the conditions of high-energy electron beams in radiotherapy.
Collapse
|