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Iseri T, Tanabe Y, Onizuka R, Torigoe Y, Horikirizono H, Itamoto K, Sunahara H, Itoh H, Tani K, Nakaichi M. A Monte Carlo study on dose distribution of an orthovoltage radiation therapy system. Phys Eng Sci Med 2023; 46:623-632. [PMID: 36940063 DOI: 10.1007/s13246-023-01237-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/23/2023] [Indexed: 03/21/2023]
Abstract
It is important to plan radiotherapy treatment and establish optimal dose distribution to reduce the chances of side effects and injury. Because there are no commercially available tools for calculating dose distribution in orthovoltage radiotherapy in companion animals, we developed an algorithm to accomplish this and verified its characteristics using tumor disease cases. First, we used the Monte Carlo method to develop an algorithm to calculate the dose distribution of orthovoltage radiotherapy (280 kVp; MBR-320, Hitachi Medical Corporation, Tokyo, Japan) using BEAMnrc at our clinic. Using development of Monte Carlo method, dose distribution for tumor and normal organs were evaluated in brain tumors, squamous cell carcinomas of the head, and feline nasal lymphomas. In all cases of brain tumors, the mean dose delivered to the GTV ranged from 36.2 to 76.1% of the prescribed dose due to the decrease through the skull. In the nasal lymphoma in cats, the eyes with covered a 2 mm-thick lead plate, the respective average dose to the eyes was 71.8% and 89.9% less than that to the uncovered eyes. The findings may be useful for informed decision making in orthovoltage radiotherapy with more effective and targeted irradiation and data collection allowing detailed informed consent.
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Affiliation(s)
- Toshie Iseri
- Department of Veterinary Radiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi-shi, Yamaguchi, Yamagishi, Japan.
| | - Yoshinori Tanabe
- Graduate School of Health Sciences, Okayama University, Okayama, Japan
| | - Ryouta Onizuka
- Department of Therapeutic Radiology, Yamaguchi University Hospital, Yamaguchi, Japan
| | - Yuri Torigoe
- Department of Veterinary Radiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi-shi, Yamaguchi, Yamagishi, Japan
| | - Hiro Horikirizono
- Department of Veterinary Radiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi-shi, Yamaguchi, Yamagishi, Japan
| | - Kazuhito Itamoto
- Animal medical center, Joint faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Hiroshi Sunahara
- Department of Veterinary Surgery, Joint faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Harumichi Itoh
- Animal medical center, Joint faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Kenji Tani
- Department of Veterinary Surgery, Joint faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Munekazu Nakaichi
- Department of Veterinary Radiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi-shi, Yamaguchi, Yamagishi, Japan
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Investigations of various gamma radiation interaction parameters of human tissues and their tissue substitute materials for dosimetric applications. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Margret M, Subramanian V, Baskaran R, Venkatraman B. Detection of scales and its thickness determination in industrial pipes using Compton backscattering system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:113117. [PMID: 30501299 DOI: 10.1063/1.5039579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
The ability to detect and quantify scales in pipes has been an important yardstick for efficient transfer of fluids in domestic as well as in application related industries. Knowledge of different kinds of scales formed has become a precondition for trouble-shooting in operational lines. In this paper, collimated Compton backscattered gamma rays from a radioactive source have been used to inspect the scales by automatic scanning in steps along the axial direction of different pipes. The methodology has been extended for the quantification of scales that prevails in the real functionality of extensive usage of fluids. To aid for descaling processes, the desideratum is the density determination of scales and this parameter is quantified non-destructively and is also validated with the standard density. The described non-intrusive gamma ray densitometry is quite promising, efficient and has highly reliable results for scale detection with the squared correlation coefficient of 0.98. The proposed technique shows a better linearity than the gammatography technique.
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Affiliation(s)
- M Margret
- Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
| | - V Subramanian
- Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
| | - R Baskaran
- Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
| | - B Venkatraman
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
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Shakhreet B, Bauk S, Shukri A. Electron density of Rhizophora spp. wood using Compton scattering technique at 15.77, 17.48 and 22.16keV XRF energies. Radiat Phys Chem Oxf Engl 1993 2015. [DOI: 10.1016/j.radphyschem.2014.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Willner M, Herzen J, Grandl S, Auweter S, Mayr D, Hipp A, Chabior M, Sarapata A, Achterhold K, Zanette I, Weitkamp T, Sztrókay A, Hellerhoff K, Reiser M, Pfeiffer F. Quantitative breast tissue characterization using grating-based x-ray phase-contrast imaging. Phys Med Biol 2014; 59:1557-71. [PMID: 24614413 DOI: 10.1088/0031-9155/59/7/1557] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
X-ray phase-contrast imaging has received growing interest in recent years due to its high capability in visualizing soft tissue. Breast imaging became the focus of particular attention as it is considered the most promising candidate for a first clinical application of this contrast modality. In this study, we investigate quantitative breast tissue characterization using grating-based phase-contrast computed tomography (CT) at conventional polychromatic x-ray sources. Different breast specimens have been scanned at a laboratory phase-contrast imaging setup and were correlated to histopathology. Ascertained tumor types include phylloides tumor, fibroadenoma and infiltrating lobular carcinoma. Identified tissue types comprising adipose, fibroglandular and tumor tissue have been analyzed in terms of phase-contrast Hounsfield units and are compared to high-quality, high-resolution data obtained with monochromatic synchrotron radiation, as well as calculated values based on tabulated tissue properties. The results give a good impression of the method's prospects and limitations for potential tumor detection and the associated demands on such a phase-contrast breast CT system. Furthermore, the evaluated quantitative tissue values serve as a reference for simulations and the design of dedicated phantoms for phase-contrast mammography.
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Affiliation(s)
- M Willner
- Department of Physics and Institute of Medical Engineering, Technische Universität München, James-Franck-Straße 1, D-85748 Garching, Germany
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Han S, Kang DG. Tissue Cancellation in Dual Energy Mammography Using a Calibration Phantom Customized for Direct Mapping. IEEE TRANSACTIONS ON MEDICAL IMAGING 2014; 33:74-84. [PMID: 24043372 DOI: 10.1109/tmi.2013.2280901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
An easily implementable tissue cancellation method for dual energy mammography is proposed to reduce anatomical noise and enhance lesion visibility. For dual energy calibration, the images of an imaging object are directly mapped onto the images of a customized calibration phantom. Each pixel pair of the low and high energy images of the imaging object was compared to pixel pairs of the low and high energy images of the calibration phantom. The correspondence was measured by absolute difference between the pixel values of imaged object and those of the calibration phantom. Then the closest pixel pair of the calibration phantom images is marked and selected. After the calibration using direct mapping, the regions with lesion yielded different thickness from the background tissues. Taking advantage of the different thickness, the visibility of cancerous lesions was enhanced with increased contrast-to-noise ratio, depending on the size of lesion and breast thickness. However, some tissues near the edge of imaged object still remained after tissue cancellation. These remaining residuals seem to occur due to the heel effect, scattering, nonparallel X-ray beam geometry and Poisson distribution of photons. To improve its performance further, scattering and the heel effect should be compensated.
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Antoniassi M, Conceição A, Poletti M. Study of electron densities of normal and neoplastic human breast tissues by Compton scattering using synchrotron radiation. Appl Radiat Isot 2012; 70:1351-4. [DOI: 10.1016/j.apradiso.2012.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 01/02/2012] [Accepted: 01/02/2012] [Indexed: 10/14/2022]
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Munro PRT, Ignatyev K, Speller RD, Olivo A. Design of a novel phase contrast x-ray imaging system for mammography. Phys Med Biol 2010; 55:4169-85. [PMID: 20601778 PMCID: PMC3736324 DOI: 10.1088/0031-9155/55/14/014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
It is hoped that x-ray phase contrast imaging (XPCi) will provide a generational improvement in the effectiveness of mammography. XPCi is sensitive to the refraction which x-rays undergo as a result of the variation in x-ray propagation speeds within an object. XPCi is, however, seldom used in clinical applications owing mainly to a lack of suitable systems. The radiation physics group at UCL has previously designed and built an XPCi system sensitive to phase gradients in one dimension for application in security inspection. We present here the design methodology and final design of a prototype XPCi system sensitive to phase gradients in two directions for use in mammography. The technique makes efficient use of the flux available from a laboratory x-ray source, thus making it suitable for clinical use.
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Affiliation(s)
- Peter R T Munro
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT, UK.
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Bige Y, Hanfeng Z, Rong W. Analysis of microstructural alterations of normal and pathological breast tissue in vivo using the AR cepstrum. ULTRASONICS 2006; 44:211-5. [PMID: 16387338 DOI: 10.1016/j.ultras.2005.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2005] [Revised: 11/06/2005] [Accepted: 11/16/2005] [Indexed: 05/06/2023]
Abstract
The mean scatterer spacing is considered to be an important parameter for describing ultrasonic scattering and characterization of biological tissue. Autoregressive models are widely used in parametric techniques for spectral estimation. In this paper, we describe the results of a careful examination of the mean scatterer spacing parameter in normal and pathological breast tissues in vivo using the autoregressive cepstrum. Our experimental results carried out at 4.5 MHz using weakly focused pulse-echo single element transducer show that the mean scatterer spacing in normal breast tissues in vivo is 1.25+/-0.21 mm whereas in several pathological breast tissues, it is between 0.82+/-0.10 and 1.09+/-0.07 mm. These results indicate good correlation with microstructure of breast tissue characterization, and hence the AR cepstrum holds promise that it could be used as an effective method for signal analysis of ultrasonic scattering and characterization of breast tissues scatterers.
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Affiliation(s)
- Yan Bige
- Applied Acoustics Institute, Shaanxi Normal University, Xi'an, Shaanxi 710062, China.
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Ryan EA, Farquharson MJ, Flinton DM. The use of Compton scattering to differentiate between classifications of normal and diseased breast tissue. Phys Med Biol 2005; 50:3337-48. [PMID: 16177513 DOI: 10.1088/0031-9155/50/14/010] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study describes a technique for measuring the electron density of breast tissue utilizing Compton scattered photons. The Kalpha2 line from a tungsten target industrial x-ray tube (57.97 keV) was used and the scattered x-rays collected at an angle of 30 degrees . At this angle the Compton and coherent photon peaks can be resolved using an energy dispersive detector and a peak fitting algorithm. The system was calibrated using solutions of known electron density. The results obtained from a pilot study of 22 tissues are presented. The tissue samples investigated comprise four different tissue classifications: adipose, malignancy, fibroadenoma and fibrocystic change (FCC). It is shown that there is a difference between adipose and malignant tissue, to a value of 9.0%, and between adipose and FCC, to a value of 12.7%. These figures are found to be significant by statistical analysis. The differences between adipose and fibroadenoma tissues (2.2%) and between malignancy and FCC (3.4%) are not significant. It is hypothesized that the alteration in glucose uptake within malignant cells may cause these tissues to have an elevated electron density. The fibrotic nature of tissue that has undergone FCC gives the highest measure of all tissue types.
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Affiliation(s)
- Elaine A Ryan
- School of Allied Health Sciences, City University, Charterhouse Square, London EC1M 6PA, UK
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