Introduction: To perform energy-dispersive X-ray imaging, we constructed a photon-counting X-ray computed tomography (CT) scanner to perform enhanced K-edge CT.
Methods: X-ray photons penetrating through an object were detected using a cadmium telluride flat panel detector (FPD) with pixel dimensions of 100 × 100 mm2, and 720 radiograms from the FPD were sent to the personal computer to reconstruct tomograms. Gadolinium (Gd) K-edge energy is 50.2 keV, and Gd-Kedge CT was carried out using photons with an energy range of 50-100 keV.
Results: Compared with low-energy CT of 15-50 keV, the gray density of muscle and bone substantially decreased, and the image contrast of Gd media was improved utilizing Gd-K-edge CT.
Conclusion: Using the cone beam, the effective pixel dimensions were 80 × 80 μm2, and blood vessels were observed at a high contrast using Gd-Kedge CT.
简介:为了进行能量色散 X 射线成像,我们构建了一个光子计数 X 射线计算机断层扫描(CT)扫描仪:为了进行能量色散 X 射线成像,我们建造了一台光子计数 X 射线计算机断层扫描(CT)扫描仪,以进行增强 K 边 CT:方法:使用像素尺寸为 100 × 100 mm2 的碲化镉平板探测器(FPD)检测穿透物体的 X 射线光子,并将 FPD 的 720 幅放射图发送到个人计算机,以重建断层图。钆(Gd)K 边能量为 50.2 keV,使用能量范围为 50-100 keV 的光子进行钆边 CT:结果:与 15-50 keV 的低能量 CT 相比,肌肉和骨骼的灰密度大幅降低,利用 Gd-Kedge CT 提高了钆介质的图像对比度:结论:利用锥形束,有效像素尺寸为 80 × 80 μm2,利用钆边缘 CT 可以观察到高对比度的血管。
{"title":"Photon-counting X-ray Computed Tomography Using a Cadmium Telluride Flat Panel Detector with High Spatial Resolutions and Dual-energy Selection.","authors":"Jiro Sato, Eiichi Sato, Kazuki Ito, Hodaka Moriyama, Osahiko Hagiwara, Toshiyuki Enomoto, Manabu Watanabe, Sohei Yoshida, Kunihiro Yoshioka, Hiroyuki Nitta","doi":"10.4103/jmp.jmp_33_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_33_24","url":null,"abstract":"<p><strong>Introduction: </strong>To perform energy-dispersive X-ray imaging, we constructed a photon-counting X-ray computed tomography (CT) scanner to perform enhanced K-edge CT.</p><p><strong>Methods: </strong>X-ray photons penetrating through an object were detected using a cadmium telluride flat panel detector (FPD) with pixel dimensions of 100 × 100 mm<sup>2</sup>, and 720 radiograms from the FPD were sent to the personal computer to reconstruct tomograms. Gadolinium (Gd) K-edge energy is 50.2 keV, and Gd-Kedge CT was carried out using photons with an energy range of 50-100 keV.</p><p><strong>Results: </strong>Compared with low-energy CT of 15-50 keV, the gray density of muscle and bone substantially decreased, and the image contrast of Gd media was improved utilizing Gd-K-edge CT.</p><p><strong>Conclusion: </strong>Using the cone beam, the effective pixel dimensions were 80 × 80 μm<sup>2</sup>, and blood vessels were observed at a high contrast using Gd-Kedge CT.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"441-447"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548080/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Introduction: The purpose of the study was to calculate, tumor control probability (TCP) and normal tissue complication probability (NTCP) in cervical cancer patients and to clinically correlate the outcomes with a follow-up period of 24 months.
Materials and methods: One hundred and fifty patients were included in the present study who received 46 Gy/23 fractions/4½ weeks of external beam radiotherapy with concurrent cisplatin chemotherapy, followed by intracavitary brachytherapy of 3 different fractionations regimens, i.e., 9.5 Gy per fraction of two fractions (50 patients in Arm1), 7.5 Gy per fraction of three fractions (50 patients in Arm2), and 6.0 Gy per fraction of four fractions (50 patients in Arm3).
Results: The median TCP value for Arm1, Arm2, and Arm3 was 99.6%, 94%, and 98.1%, respectively, (P < 0.01). The median NTCP value for bladder in Arm1, Arm2, and Arm3 was 0.17%, 0.04%, and 0.07%, respectively, (P = 0.05). The median NTCP value for rectum in Arm1, Arm2, and Arm3 was 4.73%, 4.35%, and 3.17%, respectively, (P = 0.052). The overall survival (OS) of 90%, 86%, and 84% was found for Arm1, Arm2, and Arm3, respectively, at 24 months of follow-up.
Conclusion: TCP, NTCP, and OS rates were found higher in Arm1 as compared to the other two arms. The complications found in all arms were less, low grade, and manageable. Hence, Arm1, i.e., 9.5 Gy per fraction of two fractions can be concluded as the optimum fractionation regime in terms of radiobiological parameters as well as overall patient comfort.
{"title":"Tumor Control and Normal Tissue Complications in High-dose-rate Brachytherapy for Cervical Cancer Patients Using Ir-192 Radioactive Source.","authors":"Gurpreet Kaur, Pardeep Garg, Vinod Kumar Dangwal, Baltej Singh, Garima Gaur, Romikant Grover, Simrandeep Singh, Rachana Sharma","doi":"10.4103/jmp.jmp_86_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_86_24","url":null,"abstract":"<p><strong>Introduction: </strong>The purpose of the study was to calculate, tumor control probability (TCP) and normal tissue complication probability (NTCP) in cervical cancer patients and to clinically correlate the outcomes with a follow-up period of 24 months.</p><p><strong>Materials and methods: </strong>One hundred and fifty patients were included in the present study who received 46 Gy/23 fractions/4½ weeks of external beam radiotherapy with concurrent cisplatin chemotherapy, followed by intracavitary brachytherapy of 3 different fractionations regimens, i.e., 9.5 Gy per fraction of two fractions (50 patients in Arm1), 7.5 Gy per fraction of three fractions (50 patients in Arm2), and 6.0 Gy per fraction of four fractions (50 patients in Arm3).</p><p><strong>Results: </strong>The median TCP value for Arm1, Arm2, and Arm3 was 99.6%, 94%, and 98.1%, respectively, (<i>P</i> < 0.01). The median NTC<i>P</i> value for bladder in Arm1, Arm2, and Arm3 was 0.17%, 0.04%, and 0.07%, respectively, (<i>P</i> = 0.05). The median NTC<i>P</i> value for rectum in Arm1, Arm2, and Arm3 was 4.73%, 4.35%, and 3.17%, respectively, (<i>P</i> = 0.052). The overall survival (OS) of 90%, 86%, and 84% was found for Arm1, Arm2, and Arm3, respectively, at 24 months of follow-up.</p><p><strong>Conclusion: </strong>TCP, NTCP, and OS rates were found higher in Arm1 as compared to the other two arms. The complications found in all arms were less, low grade, and manageable. Hence, Arm1, i.e., 9.5 Gy per fraction of two fractions can be concluded as the optimum fractionation regime in terms of radiobiological parameters as well as overall patient comfort.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"363-369"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01Epub Date: 2024-09-21DOI: 10.4103/jmp.jmp_60_24
Taehyung Kim, Jeongun Kim, Engchan Kim
Objectives: The purpose of this study was to develop a prototype for controlling the water level of a three-dimensional (3D) water phantom using ultrasound sensors and Arduino technology and evaluate its performance in setting up the 3D water phantom for radiation beam measurements.
Materials and methods: A prototype consisted of an Arduino Nano board and two types of ultrasound sensors (US015 and SR04). The accuracy of both sensors was tested at various distances and the performance was evaluated through statistical analysis. The distance measurement test was performed rigorously at intervals of 2 cm from 5 cm to 21 cm, measuring an average error and a maximum deviation for each sensor.
Results: Both sensors demonstrated the measurement accuracy within 2 mm. When using the traditional and prototype-based setup methods, the measured photon and electron beam profiles did not show any significant difference. This result suggests the equivalent setup capability when using these two different 3D water phantom setup methods.
Conclusion: The ultrasound sensor-based prototype is demonstrated as a more effective device in maintaining the 3D water phantom setup consistently compared to the traditional method, which is prone to human error, and it will aid in facilitating precise phantom setup during the commissioning and routine quality assurance (QA) of linear accelerators in radiotherapy clinics.
{"title":"Ultrasonic Sensor-based Water Leveling for Three-dimensional Water Phantom: Prototype Development.","authors":"Taehyung Kim, Jeongun Kim, Engchan Kim","doi":"10.4103/jmp.jmp_60_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_60_24","url":null,"abstract":"<p><strong>Objectives: </strong>The purpose of this study was to develop a prototype for controlling the water level of a three-dimensional (3D) water phantom using ultrasound sensors and Arduino technology and evaluate its performance in setting up the 3D water phantom for radiation beam measurements.</p><p><strong>Materials and methods: </strong>A prototype consisted of an Arduino Nano board and two types of ultrasound sensors (US015 and SR04). The accuracy of both sensors was tested at various distances and the performance was evaluated through statistical analysis. The distance measurement test was performed rigorously at intervals of 2 cm from 5 cm to 21 cm, measuring an average error and a maximum deviation for each sensor.</p><p><strong>Results: </strong>Both sensors demonstrated the measurement accuracy within 2 mm. When using the traditional and prototype-based setup methods, the measured photon and electron beam profiles did not show any significant difference. This result suggests the equivalent setup capability when using these two different 3D water phantom setup methods.</p><p><strong>Conclusion: </strong>The ultrasound sensor-based prototype is demonstrated as a more effective device in maintaining the 3D water phantom setup consistently compared to the traditional method, which is prone to human error, and it will aid in facilitating precise phantom setup during the commissioning and routine quality assurance (QA) of linear accelerators in radiotherapy clinics.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"387-393"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548072/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01Epub Date: 2024-09-21DOI: 10.4103/jmp.jmp_48_24
Jan Risty Lucido Marzon, Vernie C Convicto, Melbagrace A Lapening, Andelson L Berondo, Angelina M Bacala
Aims: The objective was to validate the initial beam parameters of the Davao Doctors Hospital's 6 MV Elekta Synergy Platform linac, which performs to the specification of the commissioning data per our records using the gamma-index analysis toolkit integrated inside PRIMO software.
Materials and methods: In PRIMO, a sequence of optimization processes is performed, in which the measured and simulated percent depth dose (PDD) and lateral beam profiles at various depths are compared, using the stringent gamma-index passing rate at 1%/1 mm criteria (GPR11). Using four fields of sizes 3 cm × 3 cm, 4 cm × 4 cm, 5 cm × 5 cm, and 10 cm × 10 cm, the dose is calculated on a water phantom measuring 16.2 cm × 16.2 cm × 30.0 cm. In addition, one field of size 20 cm × 20 cm is used on a 50.0 cm × 50.0 cm × 30.0 cm water phantom with a bin size of 0.2 cm × 0.2 cm × 0.2 cm at a source-surface distance of 100.0 cm.
Results: For PDD and beam profiles comparison at the largest field size, the 6.5 MeV initial electron beam energy, 0.25 MeV full-width-half-maximum energy, 0.20 cm focal spot size, and 3° beam divergence tuned configuration yield GPR11 values of 94.0% and 97.7% (PRIMO PDD and lateral beam profile at 200 mm scan depth, respectively) with a statistical uncertainty of 2.9%. For lower field sizes, the GPR11 values are consistent at more than 90% for the PDD, whereas GPR11 values of 80.3% and 70.6% for the lateral beam profiles (at 15 mm and 200 mm scan depths) at 10 cm × 10 cm and 5 cm × 5 cm, respectively. The percentage difference between the measured and simulated PDD20,10 ratios of not more than 2.45% is observed in all field settings.
Conclusions: These tuned beam parameters are remarkably in agreement with the suggested beam parameters listed on the PRIMO website for the 6 MV Elekta linac which was optimized with a different set of measurements.
{"title":"Validation of the Elekta Synergy Platform Linac at 6 MV Photon Beam using PRIMO Monte Carlo Software.","authors":"Jan Risty Lucido Marzon, Vernie C Convicto, Melbagrace A Lapening, Andelson L Berondo, Angelina M Bacala","doi":"10.4103/jmp.jmp_48_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_48_24","url":null,"abstract":"<p><strong>Aims: </strong>The objective was to validate the initial beam parameters of the Davao Doctors Hospital's 6 MV Elekta Synergy Platform linac, which performs to the specification of the commissioning data per our records using the gamma-index analysis toolkit integrated inside PRIMO software.</p><p><strong>Materials and methods: </strong>In PRIMO, a sequence of optimization processes is performed, in which the measured and simulated percent depth dose (PDD) and lateral beam profiles at various depths are compared, using the stringent gamma-index passing rate at 1%/1 mm criteria (GPR11). Using four fields of sizes 3 cm × 3 cm, 4 cm × 4 cm, 5 cm × 5 cm, and 10 cm × 10 cm, the dose is calculated on a water phantom measuring 16.2 cm × 16.2 cm × 30.0 cm. In addition, one field of size 20 cm × 20 cm is used on a 50.0 cm × 50.0 cm × 30.0 cm water phantom with a bin size of 0.2 cm × 0.2 cm × 0.2 cm at a source-surface distance of 100.0 cm.</p><p><strong>Results: </strong>For PDD and beam profiles comparison at the largest field size, the 6.5 MeV initial electron beam energy, 0.25 MeV full-width-half-maximum energy, 0.20 cm focal spot size, and 3° beam divergence tuned configuration yield GPR11 values of 94.0% and 97.7% (PRIMO PDD and lateral beam profile at 200 mm scan depth, respectively) with a statistical uncertainty of 2.9%. For lower field sizes, the GPR11 values are consistent at more than 90% for the PDD, whereas GPR11 values of 80.3% and 70.6% for the lateral beam profiles (at 15 mm and 200 mm scan depths) at 10 cm × 10 cm and 5 cm × 5 cm, respectively. The percentage difference between the measured and simulated <i>PDD</i> <sub>20,10</sub> ratios of not more than 2.45% is observed in all field settings.</p><p><strong>Conclusions: </strong>These tuned beam parameters are remarkably in agreement with the suggested beam parameters listed on the PRIMO website for the 6 MV Elekta linac which was optimized with a different set of measurements.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"410-418"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548066/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Introduction: Cancer tissue absorbs 3-8 times more glucose than normal tissue. Therefore, we developed a gadobutrol-glucose solution for 7.0T magnetic resonance imaging to visualize whole cancerous regions at high contrast.
Methods: The contrast medium consists of gadobutrol and glucose solutions, and these solutions are mixed before the vein infusion. We used readily available solutions, and the concentrations of the gadobutrol and glucose solutions were 60% and 5.0%, respectively. To visualize the cancerous region, we used two rabbits with VX7 thigh cancer. First, vein injection was carried out using a gadobutrol-saline solution containing 0.3 ml gadobutrol, and T1-weighted imaging (T1WI) was performed. Twenty-four hours after the first experiment, we performed T1WI of the VX7-cancer region using 50.3 mL gadobutrol-glucose solution including 0.3 ml gadobutrol.
Results: Compared with T1WI using the gadobutrol-saline solution, the signal intensity of the cancerous region substantially increased using the gadobutrol-glucose solution.
Conclusion: We confirmed significant signal-intensity increases in the whole VX7-cancer region of a rabbit thigh utilizing vein infusion of gadobutrol-glucose solution since the gadobutrol molecules were absorbed throughout the cancerous region along with glucose molecules.
{"title":"Whole Cancer Visualization using Gadobutrol-glucose Solution and 7.0 T Magnetic Resonance Imaging.","authors":"Manabu Watanabe, Eiichi Sato, Jiro Sato, Kazuki Ito, Hodaka Moriyama, Osahiko Hagiwara, Toshiyuki Enomoto, Ryoko Yoshida, Susumu Hayakawa, Yuichi Sato, Sohei Yoshida, Kunihiro Yoshioka, Hiroyuki Nitta","doi":"10.4103/jmp.jmp_42_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_42_24","url":null,"abstract":"<p><strong>Introduction: </strong>Cancer tissue absorbs 3-8 times more glucose than normal tissue. Therefore, we developed a gadobutrol-glucose solution for 7.0T magnetic resonance imaging to visualize whole cancerous regions at high contrast.</p><p><strong>Methods: </strong>The contrast medium consists of gadobutrol and glucose solutions, and these solutions are mixed before the vein infusion. We used readily available solutions, and the concentrations of the gadobutrol and glucose solutions were 60% and 5.0%, respectively. To visualize the cancerous region, we used two rabbits with VX7 thigh cancer. First, vein injection was carried out using a gadobutrol-saline solution containing 0.3 ml gadobutrol, and T1-weighted imaging (T1WI) was performed. Twenty-four hours after the first experiment, we performed T1WI of the VX7-cancer region using 50.3 mL gadobutrol-glucose solution including 0.3 ml gadobutrol.</p><p><strong>Results: </strong>Compared with T1WI using the gadobutrol-saline solution, the signal intensity of the cancerous region substantially increased using the gadobutrol-glucose solution.</p><p><strong>Conclusion: </strong>We confirmed significant signal-intensity increases in the whole VX7-cancer region of a rabbit thigh utilizing vein infusion of gadobutrol-glucose solution since the gadobutrol molecules were absorbed throughout the cancerous region along with glucose molecules.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"427-432"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548070/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aim: This article examines India's present radiotherapy (RT) machine status and requirements, geographical distribution, and infrastructure need in six regional areas, which include 31 member states and union territories (UTs). It also considers the influence of the COVID-19 pandemic on India's teletherapy sector.
Materials and methods: Data from reliable resources, including Atomic Energy Regulatory Board, Global Cancer Observatory, and Directory of Radiotherapy Centres databases, were used to analyze the current status of RT machine (RTM) density, regional disparity, and COVID-19 impact on infrastructure growth-rate.
Results: In India, the number of functioning RTM and facilities are 823 and 554, respectively, with an average of 1.5 RTM per institute, of which 69.4% have only one RTM. Over the past 22 years, there has been a paradigm shift towards medical linear accelerator (linac) installation instead of telecobalt machines. Presently, there is a teletherapy density of 0.6 RTM per million population, and there is a shortfall of 1209 RTMs. There is a considerable regional disparity in the distribution of RTMs, ranging from (0.08 RTM/million-2.94 RTM/million) across different regions. There is a significant demand for RTMs in the Northern region (480) and the state of Uttar Pradesh (279). The COVID-19 pandemic temporarily impacted India's RT growth rate, reducing it from 5% to 1.9% in 2020-2021.
Conclusions: New policies must be established to accelerate the rate of RT installation growth. To better serve local populations and save patient costs, this article proposes that RT facilities be dispersed equitably across states.
{"title":"An Analysis of Radiotherapy Machine Requirements in India: Impact of the Pandemic and Regional Disparities.","authors":"Rohit Singh Chauhan, Anusheel Munshi, Anirudh Pradhan","doi":"10.4103/jmp.jmp_20_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_20_24","url":null,"abstract":"<p><strong>Aim: </strong>This article examines India's present radiotherapy (RT) machine status and requirements, geographical distribution, and infrastructure need in six regional areas, which include 31 member states and union territories (UTs). It also considers the influence of the COVID-19 pandemic on India's teletherapy sector.</p><p><strong>Materials and methods: </strong>Data from reliable resources, including Atomic Energy Regulatory Board, Global Cancer Observatory, and Directory of Radiotherapy Centres databases, were used to analyze the current status of RT machine (RTM) density, regional disparity, and COVID-19 impact on infrastructure growth-rate.</p><p><strong>Results: </strong>In India, the number of functioning RTM and facilities are 823 and 554, respectively, with an average of 1.5 RTM per institute, of which 69.4% have only one RTM. Over the past 22 years, there has been a paradigm shift towards medical linear accelerator (linac) installation instead of telecobalt machines. Presently, there is a teletherapy density of 0.6 RTM per million population, and there is a shortfall of 1209 RTMs. There is a considerable regional disparity in the distribution of RTMs, ranging from (0.08 RTM/million-2.94 RTM/million) across different regions. There is a significant demand for RTMs in the Northern region (480) and the state of Uttar Pradesh (279). The COVID-19 pandemic temporarily impacted India's RT growth rate, reducing it from 5% to 1.9% in 2020-2021.</p><p><strong>Conclusions: </strong>New policies must be established to accelerate the rate of RT installation growth. To better serve local populations and save patient costs, this article proposes that RT facilities be dispersed equitably across states.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"370-378"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548067/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01Epub Date: 2024-09-21DOI: 10.4103/jmp.jmp_52_24
Antria Filippou, Christakis Damianou
Aim: Phantoms are often utilized for the preclinical evaluation of novel high-intensity focused ultrasound (HIFU) systems, serving as valuable tools for validating efficacy. In the present study, the feasibility of a homogeneous agar-based breast-shaped phantom as a tool for the preclinical evaluation of HIFU systems dedicated to breast cancer was assessed. Specifically, the effect of the increased phantom curvature on temperature increase was examined through sonications executed on two sides having varied curvatures.
Materials and methods: Assessment was performed utilizing a 1.1 MHz focused transducer. Sonications on the two phantom sides were executed at varied acoustical power in both a laboratory setting and inside a 1.5 T magnetic resonance imaging scanner. Sonications were independently performed on two identical phantoms for repeatability purposes.
Results: Temperature changes between 7.1°C-34.3°C and 5.1°C-21.5°C were recorded within the decreased and increased curvature sides, respectively, for acoustical power of 3.75-10 W. High-power sonications created lesions which were approximately symmetrically formed around the focal point at the decreased curvature side, while they were shifted away from the focal point at the increased curvature side.
Conclusions: The present findings indicate that increased curvature of the breast phantom results in deformed focal shapes and decreased temperatures induced at the focal area, thus suggesting treatment correction requirements in the form of focus control or accurate robotic movement. The developed breast-shaped phantom can be utilized as an evaluation tool of HIFU systems dedicated to breast cancer since it can visually verify the efficacy of any system.
目的:模型通常用于新型高强度聚焦超声(HIFU)系统的临床前评估,是验证疗效的重要工具。本研究评估了将基于琼脂的均匀乳房模型作为乳腺癌专用 HIFU 系统临床前评估工具的可行性。具体来说,通过对具有不同曲率的两面进行超声波处理,研究了增加模型曲率对温度升高的影响:使用 1.1 MHz 聚焦换能器进行评估。在实验室环境和 1.5 T 磁共振成像扫描仪内,以不同的声功率对两个模型面进行声波扫描。为了达到可重复性的目的,在两个完全相同的模型上独立进行了声波扫描:在声波功率为 3.75-10 W 时,曲率减小侧和曲率增大侧的温度变化分别为 7.1°C-34.3°C 和 5.1°C-21.5°C。高功率声波造成的病灶在曲率减小侧的病灶周围大致对称,而在曲率增大侧的病灶则远离病灶:本研究结果表明,乳房模型的弧度增加会导致病灶形状变形和病灶区域的温度降低,因此需要通过病灶控制或精确的机器人移动来进行治疗校正。开发的乳房模型可用作乳腺癌专用 HIFU 系统的评估工具,因为它可以直观地验证任何系统的功效。
{"title":"Agar-based Phantom for Evaluating Targeting of High-intensity Focused Ultrasound Systems for Breast Ablation.","authors":"Antria Filippou, Christakis Damianou","doi":"10.4103/jmp.jmp_52_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_52_24","url":null,"abstract":"<p><strong>Aim: </strong>Phantoms are often utilized for the preclinical evaluation of novel high-intensity focused ultrasound (HIFU) systems, serving as valuable tools for validating efficacy. In the present study, the feasibility of a homogeneous agar-based breast-shaped phantom as a tool for the preclinical evaluation of HIFU systems dedicated to breast cancer was assessed. Specifically, the effect of the increased phantom curvature on temperature increase was examined through sonications executed on two sides having varied curvatures.</p><p><strong>Materials and methods: </strong>Assessment was performed utilizing a 1.1 MHz focused transducer. Sonications on the two phantom sides were executed at varied acoustical power in both a laboratory setting and inside a 1.5 T magnetic resonance imaging scanner. Sonications were independently performed on two identical phantoms for repeatability purposes.</p><p><strong>Results: </strong>Temperature changes between 7.1°C-34.3°C and 5.1°C-21.5°C were recorded within the decreased and increased curvature sides, respectively, for acoustical power of 3.75-10 W. High-power sonications created lesions which were approximately symmetrically formed around the focal point at the decreased curvature side, while they were shifted away from the focal point at the increased curvature side.</p><p><strong>Conclusions: </strong>The present findings indicate that increased curvature of the breast phantom results in deformed focal shapes and decreased temperatures induced at the focal area, thus suggesting treatment correction requirements in the form of focus control or accurate robotic movement. The developed breast-shaped phantom can be utilized as an evaluation tool of HIFU systems dedicated to breast cancer since it can visually verify the efficacy of any system.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"343-355"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548075/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose: The distribution of neutron ambient dose equivalent within the TrueBeam 10 MV photon chamber was investigated.
Materials and methods: The research used particle and heavy ion transport code system (PHITS) code and JENDL-5.0 to simulate the neutron ambient dose equivalent on and around TrueBeam's head. The simulated results were compared with the measured results using CR-39 detectors when TrueBeam radiated 5000 monitor units of 10 MV photons with field sizes 20 cm × 20 cm and 0.5 cm × 0.5 cm.
Results: Out of field size, the neutron ambient dose equivalents of the 0.5 cm × 0.5 cm field size are higher than those values of the 20 cm × 20 cm field size from 4% to 30%. The differences between the simulated value and the measured value of the neutron ambient dose equivalents at all points out of field size are smaller than 20%.
Conclusion: The neutron ambient dose equivalents, simulated with PHITS and JENDL-5.0, are satisfied with the measured neutron ambient dose equivalent.
{"title":"Photon and Neutron Dose Estimation Using Monte Carlo Simulation in TrueBeam's Room.","authors":"Soai Dang Quoc, Toshioh Fujibuchi, Hiroyuki Arakawa, Keisuke Hamada","doi":"10.4103/jmp.jmp_70_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_70_24","url":null,"abstract":"<p><strong>Purpose: </strong>The distribution of neutron ambient dose equivalent within the TrueBeam 10 MV photon chamber was investigated.</p><p><strong>Materials and methods: </strong>The research used particle and heavy ion transport code system (PHITS) code and JENDL-5.0 to simulate the neutron ambient dose equivalent on and around TrueBeam's head. The simulated results were compared with the measured results using CR-39 detectors when TrueBeam radiated 5000 monitor units of 10 MV photons with field sizes 20 cm × 20 cm and 0.5 cm × 0.5 cm.</p><p><strong>Results: </strong>Out of field size, the neutron ambient dose equivalents of the 0.5 cm × 0.5 cm field size are higher than those values of the 20 cm × 20 cm field size from 4% to 30%. The differences between the simulated value and the measured value of the neutron ambient dose equivalents at all points out of field size are smaller than 20%.</p><p><strong>Conclusion: </strong>The neutron ambient dose equivalents, simulated with PHITS and JENDL-5.0, are satisfied with the measured neutron ambient dose equivalent.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"473-479"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548078/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01Epub Date: 2024-09-21DOI: 10.4103/jmp.jmp_89_24
Sri Lakshmi Devi Kanumilli, Bhanu P Kosuru, Faiza Shaukat, Uday Kumar Repalle
Three-dimensional (3D) printing technology has revolutionized surgical practices, offering precise solutions for planning, education, and patient care. Surgeons now wield tangible, patient-specific 3D models derived from imaging data, allowing for meticulous presurgical planning. These models enhance surgical precision, reduce operative times, and minimize complications, ultimately improving patient outcomes. The technology also serves as a powerful educational tool, providing hands-on learning experiences for medical professionals and clearer communication with patients and their families. Despite its advantages, challenges such as model accuracy and material selection exist. Ongoing advancements, including bioactive materials and artificial intelligence integration, promise to further enhance 3D printing's impact. The future of 3D printing in surgery holds potential for regenerative medicine, increased global accessibility, and collaboration through telemedicine. Interdisciplinary collaboration between medical and engineering fields is crucial for responsible and innovative use of this technology.
三维(3D)打印技术给外科手术带来了革命性的变化,为规划、教育和病人护理提供了精确的解决方案。外科医生现在可以利用从成像数据中提取的病人专用三维模型,进行细致的术前规划。这些模型提高了手术的精确度,缩短了手术时间,最大限度地减少了并发症,最终改善了患者的预后。该技术还可作为一种强大的教育工具,为医疗专业人员提供实践学习体验,并与患者及其家属进行更清晰的沟通。尽管该技术具有诸多优势,但在模型准确性和材料选择等方面仍存在挑战。包括生物活性材料和人工智能集成在内的不断进步有望进一步增强 3D 打印的影响力。未来,3D 打印技术在外科手术中的应用将为再生医学、提高全球可及性和通过远程医疗开展协作带来潜力。医学和工程领域的跨学科合作对于负责任地创新使用这项技术至关重要。
{"title":"Advancements and Applications of Three-dimensional Printing Technology in Surgery.","authors":"Sri Lakshmi Devi Kanumilli, Bhanu P Kosuru, Faiza Shaukat, Uday Kumar Repalle","doi":"10.4103/jmp.jmp_89_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_89_24","url":null,"abstract":"<p><p>Three-dimensional (3D) printing technology has revolutionized surgical practices, offering precise solutions for planning, education, and patient care. Surgeons now wield tangible, patient-specific 3D models derived from imaging data, allowing for meticulous presurgical planning. These models enhance surgical precision, reduce operative times, and minimize complications, ultimately improving patient outcomes. The technology also serves as a powerful educational tool, providing hands-on learning experiences for medical professionals and clearer communication with patients and their families. Despite its advantages, challenges such as model accuracy and material selection exist. Ongoing advancements, including bioactive materials and artificial intelligence integration, promise to further enhance 3D printing's impact. The future of 3D printing in surgery holds potential for regenerative medicine, increased global accessibility, and collaboration through telemedicine. Interdisciplinary collaboration between medical and engineering fields is crucial for responsible and innovative use of this technology.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"319-325"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548071/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose: This study aims to investigate the radiation enhancement effects of ultrasound-stimulated microbubbles (USMB) with X-rays and nanoparticles on pancreatic cancer cells invitro.
Methods: Sonazoid™ microbubbles were used for USMB treatment with a commercially available ultrasound unit. The characterization of the microbubbles before and after ultrasound exposure with different mechanical parameters was evaluated microscopically. Two pancreatic cancer cell lines, MIAPaCa-2 and PANC-1, were treated with different concentrations of microbubbles in combination with 150 kVp X-rays and hydrogen peroxide-modified titanium dioxide nanoparticles. Cell viability was evaluated using a water-soluble tetrazolium dye and a colony formation assay. In addition, intracellular reactive oxygen species (ROS) induced by the combined treatment were assessed.
Results: The number of burst microbubbles increased with ultrasound's higher mechanical index and the exposure time. A significant radiation enhancement effect with a significant increase in ROS levels was observed in MIAPaCa-2 cells treated with USMB and 6 Gy X-rays, whereas it was not significant in PANC-1 cells treated with the same. When a higher concentration of USMB was applied with X-rays, no radiation enhancement effects were observed in either cell line. Moreover, there was no radiation enhancement effect by USMB between cells treated with and without nanoparticles.
Conclusions: The results indicate that USMB treatment can additively enhance the therapeutic efficacy of radiation therapy on pancreatic cancer cells, while the synergistic enhancement effects are likely to be cell type and microbubble concentration dependent. In addition, USMB did not improve the efficacy of nanoparticle-induced radiosensitization in the current setting.
目的:本研究旨在探讨超声刺激微气泡(USMB)与 X 射线和纳米粒子在体外对胰腺癌细胞的辐射增强效应:方法:使用市售超声设备对 Sonazoid™ 微气泡进行 USMB 处理。用显微镜评估了不同机械参数的超声暴露前后微泡的特性。用不同浓度的微气泡结合 150 kVp X 射线和过氧化氢修饰的二氧化钛纳米粒子处理两种胰腺癌细胞系 MIAPaCa-2 和 PANC-1。使用水溶性四氮唑染料和菌落形成检测法评估细胞活力。此外,还对联合处理诱导的细胞内活性氧(ROS)进行了评估:结果:爆裂微气泡的数量随着超声的机械指数和暴露时间的增加而增加。在接受 USMB 和 6 Gy X 射线处理的 MIAPaCa-2 细胞中观察到了明显的辐射增强效应,ROS 水平显著增加,而在接受同样处理的 PANC-1 细胞中则不明显。当较高浓度的 USMB 与 X 射线一起使用时,在两种细胞系中均未观察到辐射增强效应。此外,用纳米颗粒处理的细胞与未用纳米颗粒处理的细胞之间也没有USMB的辐射增强效应:结论:研究结果表明,USMB 处理可增强放射治疗对胰腺癌细胞的疗效,而协同增强效应可能与细胞类型和微泡浓度有关。此外,在目前的情况下,USMB并不能提高纳米粒子诱导的放射增敏疗效。
{"title":"Ultrasound-stimulated Microbubbles for Treatment of Pancreatic Cancer Cells with Radiation and Nanoparticles: <i>In vitro</i> Study.","authors":"Masao Nakayama, Ayaha Noda, Hiroaki Akasaka, Takahiro Tominaga, Giulia McCorkell, Moshi Geso, Ryohei Sasaki","doi":"10.4103/jmp.jmp_30_24","DOIUrl":"https://doi.org/10.4103/jmp.jmp_30_24","url":null,"abstract":"<p><strong>Purpose: </strong>This study aims to investigate the radiation enhancement effects of ultrasound-stimulated microbubbles (USMB) with X-rays and nanoparticles on pancreatic cancer cells <i>in</i> <i>vitro</i>.</p><p><strong>Methods: </strong>Sonazoid™ microbubbles were used for USMB treatment with a commercially available ultrasound unit. The characterization of the microbubbles before and after ultrasound exposure with different mechanical parameters was evaluated microscopically. Two pancreatic cancer cell lines, MIAPaCa-2 and PANC-1, were treated with different concentrations of microbubbles in combination with 150 kVp X-rays and hydrogen peroxide-modified titanium dioxide nanoparticles. Cell viability was evaluated using a water-soluble tetrazolium dye and a colony formation assay. In addition, intracellular reactive oxygen species (ROS) induced by the combined treatment were assessed.</p><p><strong>Results: </strong>The number of burst microbubbles increased with ultrasound's higher mechanical index and the exposure time. A significant radiation enhancement effect with a significant increase in ROS levels was observed in MIAPaCa-2 cells treated with USMB and 6 Gy X-rays, whereas it was not significant in PANC-1 cells treated with the same. When a higher concentration of USMB was applied with X-rays, no radiation enhancement effects were observed in either cell line. Moreover, there was no radiation enhancement effect by USMB between cells treated with and without nanoparticles.</p><p><strong>Conclusions: </strong>The results indicate that USMB treatment can additively enhance the therapeutic efficacy of radiation therapy on pancreatic cancer cells, while the synergistic enhancement effects are likely to be cell type and microbubble concentration dependent. In addition, USMB did not improve the efficacy of nanoparticle-induced radiosensitization in the current setting.</p>","PeriodicalId":51719,"journal":{"name":"Journal of Medical Physics","volume":"49 3","pages":"326-334"},"PeriodicalIF":0.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11548062/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}