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1.
Radiat Prot Dosimetry ; 200(2): 130-142, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-37961917

RESUMEN

Previously, we have developed DynamicMC for modeling relative movement of Oak Ridge National Laboratory phantom in a radiation field for the Monte Carlo N-Particle package (Health Physics. 2023,124(4):301-309). Using this software, three-dimensional dose distributions in a phantom irradiated by a certain mono-energetic (Mono E) source can be deduced through its graphical user interface. In this study, we extended DynamicMC to be used in combination with the Particle and Heavy Ion Transport code System (PHITS) by providing it with a higher flexibility for dynamic movement for an anthropomorphic phantom. For this purpose, we implemented four new functions into the software, which are (1) to generate not only Mono E sources but also those having an energy spectrum of an arbitrary radioisotope (2) to calculate the absorbed doses for several radiologically important organs (3) to automatically average the calculated absorbed doses along the path of the phantom and (4) to generate user-defined slab shielding materials. The first and third items utilize the PHITS-specific modalities named radioisotope-source and sumtally functions, respectively. The computational cost and complexity can be dramatically reduced with these features. We anticipate that the present work and the developed open-source tools will be in the interest of nuclear radiation physics community for research and teaching purposes.


Asunto(s)
Física Sanitaria , Radiometría , Radiometría/métodos , Física Sanitaria/métodos , Programas Informáticos , Movimiento , Fantasmas de Imagen , Radioisótopos , Método de Montecarlo
2.
Health Phys ; 120(6): 693-698, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33879651

RESUMEN

ABSTRACT: Public communication about radiation is tricky business. Members of the public are frequently skeptical about messages from scientific sources, particularly when it comes to radiation. As radiation protection professionals, it is our job to relay scientifically sound information in a simple, clear, and concise manner. This paper discusses the Health Physics Society's "Ask The Experts" feature, the society's most successful public education endeavor with over one million visitors annually. The keys to effective communication of technical information are demonstrating empathy and compassion, keeping the language simple and concise, and offering sources of additional information to empower the individual to learn more on their own. The two most common categories of questions-radiation exposures from diagnostic imaging procedures and radiation exposures to the fetus-are discussed in detail, and some general information on how to respond to these types of questions is provided. A template for responding to public questions is provided, along with some examples.


Asunto(s)
Física Sanitaria , Protección Radiológica , Feto , Física Sanitaria/métodos
5.
Phys Med ; 56: 90-93, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30449653

RESUMEN

Big data and deep learning will profoundly change various areas of professions and research in the future. This will also happen in medicine and medical imaging in particular. As medical physicists, we should pursue beyond the concept of technical quality to extend our methodology and competence towards measuring and optimising the diagnostic value in terms of how it is connected to care outcome. Functional implementation of such methodology requires data processing utilities starting from data collection and management and culminating in the data analysis methods. Data quality control and validation are prerequisites for the deep learning application in order to provide reliable further analysis, classification, interpretation, probabilistic and predictive modelling from the vast heterogeneous big data. Challenges in practical data analytics relate to both horizontal and longitudinal analysis aspects. Quantitative aspects of data validation, quality control, physically meaningful measures, parameter connections and system modelling for the future artificial intelligence (AI) methods are positioned firmly in the field of Medical Physics profession. It is our interest to ensure that our professional education, continuous training and competence will follow this significant global development.


Asunto(s)
Macrodatos , Aprendizaje Profundo , Diagnóstico por Imagen/métodos , Física Sanitaria/métodos , Europa (Continente) , Personal de Salud , Humanos , Sociedades Médicas
6.
Int J Radiat Oncol Biol Phys ; 102(3): 635-641, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30244881

RESUMEN

PURPOSE: To investigate a new clinical role for medical physicists in direct patient care with a prospective phase 2 clinical trial. MATERIALS AND METHODS: Medical physicists participated in the Physics Direct Patient Care (PDPC) protocol, establishing independent professional relationships with radiation oncology patients. After attending a dedicated patient communication training program, medical physicists routinely met with patients for 2 physicist-patient consults to explain the treatment planning and delivery process, review the patient's treatment plan, and answer all technical questions. The first physicist-patient consult took place immediately before the computed tomography simulation, and the second took place immediately before the first treatment. Questionnaires were administered to each patient on the PDPC protocol at 3 time points to assess both anxiety and satisfaction. The first questionnaire was given shortly after the first physicist-patient consult, the second questionnaire was given shortly after the second physicist-patient consult, and the third questionnaire was given after the last treatment appointment, with no associated physicist-patient consult. RESULTS: The mean patient anxiety score was considered to be low at all questionnaire time points. There was a statistically significant decrease (P < .0001) in anxiety from the simulation time point to the first treatment time point. The mean patient technical satisfaction score was considered to be high at all measurement time points. There was a statistically significant increase (P = .0012) in technical satisfaction from the simulation time point to the first treatment time point. There was a statistically significant decrease (P < .023) in technical satisfaction from the first treatment time point to the last treatment time point. CONCLUSIONS: Establishing a new clinical role for medical physicists and investigating its effects on patient anxiety and satisfaction have created the foundation for future studies. Based on the results of this trial, the PDPC protocol will be expanded to a larger group of medical physicists, radiation oncologists, and patient disease sites and investigated with a randomized phase 3 clinical trial.


Asunto(s)
Física Sanitaria/métodos , Física Sanitaria/organización & administración , Neoplasias/psicología , Neoplasias/radioterapia , Oncología por Radiación/métodos , Oncología por Radiación/organización & administración , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad , Competencia Clínica , Simulación por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Participación del Paciente , Satisfacción del Paciente , Relaciones Profesional-Paciente , Estudios Prospectivos , Planificación de la Radioterapia Asistida por Computador , Encuestas y Cuestionarios , Tomografía Computarizada por Rayos X
7.
Health Phys ; 115(4): 512-522, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30148816

RESUMEN

Science and technology have outpaced our human ability to process and analyze the myriad data systems that extend throughout an enterprise of health care networks. Medical physicists must learn to work collaboratively with computer programmers, data scientists, administrators, and health care providers in the data-rich environment of modern health care, embracing and practicing a new discipline: cloud-based medical physics. This article addresses four distinct topics: (1) Evolution of health care systems, networks and electronic medical records (EMR); (2) Evolution of medical physics with scientific discoveries and technological advancements; (3) Evolution of information technology including; metadata, enterprise and the cloud; and (4) Medical physics enterprise: adaptive approach to quality and safety for the 21st Century.


Asunto(s)
Seguridad Computacional , Exactitud de los Datos , Registros Electrónicos de Salud , Física Sanitaria/instrumentación , Física Sanitaria/métodos , Atención a la Salud , Fluoroscopía , Humanos , Internet , Imagen por Resonancia Magnética , Medicina Nuclear , Tomografía Computarizada por Rayos X , Ultrasonografía , Rayos X
8.
Phys Med ; 41: 26-32, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28583292

RESUMEN

PURPOSE: The purpose of this study is to evaluate the usefulness of the design of experiments in the analysis of multiparametric problems related to the quality assurance in radiotherapy. The main motivation is to use this statistical method to optimize the quality assurance processes in the validation of beam models. METHOD: Considering the Varian Eclipse system, eight parameters with several levels were selected: energy, MLC, depth, X, Y1 and Y2 jaw dimensions, wedge and wedge jaw. A Taguchi table was used to define 72 validation tests. Measurements were conducted in water using a CC04 on a TrueBeam STx, a TrueBeam Tx, a Trilogy and a 2300IX accelerator matched by the vendor. Dose was computed using the AAA algorithm. The same raw data was used for all accelerators during the beam modelling. RESULTS: The mean difference between computed and measured doses was 0.1±0.5% for all beams and all accelerators with a maximum difference of 2.4% (under the 3% tolerance level). For all beams, the measured doses were within 0.6% for all accelerators. The energy was found to be an influencing parameter but the deviations observed were smaller than 1% and not considered clinically significant. CONCLUSION: Designs of experiment can help define the optimal measurement set to validate a beam model. The proposed method can be used to identify the prognostic factors of dose accuracy. The beam models were validated for the 4 accelerators which were found dosimetrically equivalent even though the accelerator characteristics differ.


Asunto(s)
Física Sanitaria/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Algoritmos , Aceleradores de Partículas , Fotones , Fenómenos Físicos , Radiometría
9.
Radiat Res ; 187(4): 406-412, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28406747

RESUMEN

Gioacchino Failla was initially appointed to operate the radon plant at Memorial Hospital in 1916. What to most people would have been a part-time temporary position was to him a career. He was not satisfied to simply fabricate radon seeds, he wanted to understand the physics and biology of the radiation emitted by the progeny of radium. His was not the first medical physics group in the United States, though it was one of the earliest, but it was the first to put such emphasis on the biological effects. After more than 28 years at Memorial Hospital, Failla moved his research group to Columbia University Medical Center and his pioneering work, blending physics and biology, has continued to date at Columbia by those that he trained or inspired, under three directors that followed him.


Asunto(s)
Biofisica/historia , Biofisica/métodos , Física Sanitaria/historia , Física Sanitaria/métodos , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Radón/química , Radón/uso terapéutico
10.
Phys Med ; 32(3): 435-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27095755

RESUMEN

Medical physics, both as a scientific discipline and clinical service, hugely contributed and still contributes to the advances in the radiotherapy of prostate cancer. The traditional translational role in developing and safely implementing new technology and methods for better optimizing, delivering and monitoring the treatment is rapidly expanding to include new fields such as quantitative morphological and functional imaging and the possibility of individually predicting outcome and toxicity. The pivotal position of medical physicists in treatment personalization probably represents the main challenge of current and next years and needs a gradual change of vision and training, without losing the traditional and fundamental role of physicists to guarantee a high quality of the treatment. The current focus issue is intended to cover traditional and new fields of investigation in prostate cancer radiation therapy with the aim to provide up-to-date reference material to medical physicists daily working to cure prostate cancer patients. The papers presented in this focus issue touch upon present and upcoming challenges that need to be met in order to further advance prostate cancer radiation therapy. We suggest that there is a smart future for medical physicists willing to perform research and innovate, while they continue to provide high-quality clinical service. However, physicists are increasingly expected to actively integrate their implicitly translational, flexible and high-level skills within multi-disciplinary teams including many clinical figures (first of all radiation oncologists) as well as scientists from other disciplines.


Asunto(s)
Física Sanitaria/métodos , Neoplasias de la Próstata/radioterapia , Humanos , Masculino , Medicina de Precisión/métodos , Planificación de la Radioterapia Asistida por Computador/métodos
11.
Phys Med ; 32(1): 7-11, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26851163

RESUMEN

Continuing Professional Development (CPD) is vital to the medical physics profession if it is to embrace the pace of change occurring in medical practice. As CPD is the planned acquisition of knowledge, experience and skills required for professional practice throughout one's working life it promotes excellence and protects the profession and public against incompetence. Furthermore, CPD is a recommended prerequisite of registration schemes (Caruana et al. 2014) and is implied in the Council Directive 2013/59/EURATOM (EU BSS) and the International Basic Safety Standards (BSS). It is to be noted that currently not all national registration schemes require CPD to maintain the registration status necessary to practise medical physics. Such schemes should consider adopting CPD as a prerequisite for renewing registration after a set period of time. This EFOMP Policy Statement, which is an amalgamation and an update of the EFOMP Policy Statements No. 8 and No. 10, presents guidelines for the establishment of national schemes for CPD and activities that should be considered for CPD.


Asunto(s)
Física Sanitaria/educación , Física Sanitaria/métodos , Curriculum , Educación Médica Continua , Unión Europea , Guías como Asunto , Política Pública , Seguridad
12.
Appl Radiat Isot ; 117: 106-110, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26777569

RESUMEN

Graphite ion chambers and semiconductor diode detectors have been used to make measurements in phantoms but these active devices represent a clear disadvantage when considered for in vivo dosimetry. In such circumstance, dosimeters with atomic number similar to human tissue are needed. Carbon nanotubes have properties that potentially meet the demand, requiring low voltage in active devices and an atomic number similar to adipose tissue. In this study, single-wall carbon nanotubes (SWCNTs) buckypaper has been used to measure the beta particle dose deposited from a strontium-90 source, the medium displaying thermoluminescence at potentially useful sensitivity. As an example, the samples show a clear response for a dose of 2Gy. This finding suggests that carbon nanotubes can be used as a passive dosimeter specifically for the high levels of radiation exposures used in radiation therapy. Furthermore, the finding points towards further potential applications such as for space radiation measurements, not least because the medium satisfies a demand for light but strong materials of minimal capacitance.


Asunto(s)
Materiales Biomiméticos/química , Materiales Biomiméticos/efectos de la radiación , Nanotubos de Carbono/química , Nanotubos de Carbono/efectos de la radiación , Papel , Dosimetría Termoluminiscente/instrumentación , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Física Sanitaria/instrumentación , Física Sanitaria/métodos , Ensayo de Materiales , Dosis de Radiación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Dosimetría Termoluminiscente/métodos
14.
Igaku Butsuri ; 35(4): 297-306, 2016.
Artículo en Japonés | MEDLINE | ID: mdl-28428465

RESUMEN

In this issue, simultaneous differential equations were introduced. These differential equations are often used in the field of medical physics. The methods for solving them were also introduced, which include Laplace transform and matrix methods. Some examples were also introduced, in which Laplace transform and matrix methods were applied to solving simultaneous differential equations derived from a three-compartment kinetic model for analyzing the glucose metabolism in tissues and Bloch equations for describing the behavior of the macroscopic magnetization in magnetic resonance imaging.In the next (final) issue, partial differential equations and various methods for solving them will be introduced together with some examples in medical physics.


Asunto(s)
Física Sanitaria/métodos , Modelos Teóricos
16.
Igaku Butsuri ; 36(1): 50-54, 2016.
Artículo en Japonés | MEDLINE | ID: mdl-28428498

RESUMEN

DICOM2PHITS and PSFC4PHITS are user assistance programs for medical physics PHITS applications. DICOM2PHITS is a program to construct the voxel PHITS simulation geometry from patient CT DICOM image data by using a conversion table from CT number to material composition. PSFC4PHITS is a program to convert the IAEA phase-space file data to PHITS format to be used as a simulation source of PHITS. Both of the programs are useful for users who want to apply PHITS simulation to verification of the treatment planning of radiation therapy. We are now developing a program to convert dose distribution obtained by PHITS to DICOM RT-dose format. We also want to develop a program which is able to implement treatment information included in other DICOM files (RT-plan and RT-structure) as a future plan.


Asunto(s)
Física Sanitaria/métodos , Diseño de Software , Simulación por Computador , Iones Pesados , Planificación de la Radioterapia Asistida por Computador/métodos
17.
Igaku Butsuri ; 36(1): 55-61, 2016.
Artículo en Japonés | MEDLINE | ID: mdl-28428499

RESUMEN

Partial differential equations are often used in the field of medical physics. In this (final) issue, the methods for solving the partial differential equations were introduced, which include separation of variables, integral transform (Fourier and Fourier-sine transforms), Green's function, and series expansion methods. Some examples were also introduced, in which the integral transform and Green's function methods were applied to solving Pennes' bioheat transfer equation and the Fourier series expansion method was applied to Navier-Stokes equation for analyzing the wall shear stress in blood vessels.Finally, the author hopes that this series will be helpful for people who engage in medical physics.


Asunto(s)
Física Sanitaria/métodos , Modelos Teóricos , Hemodinámica , Humanos , Factores de Tiempo
18.
Med Phys ; 42(11): 6658-70, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26520756

RESUMEN

Quality control (QC) in medical imaging is an ongoing process and not just a series of infrequent evaluations of medical imaging equipment. The QC process involves designing and implementing a QC program, collecting and analyzing data, investigating results that are outside the acceptance levels for the QC program, and taking corrective action to bring these results back to an acceptable level. The QC process involves key personnel in the imaging department, including the radiologist, radiologic technologist, and the qualified medical physicist (QMP). The QMP performs detailed equipment evaluations and helps with oversight of the QC program, the radiologic technologist is responsible for the day-to-day operation of the QC program. The continued need for ongoing QC in digital radiography has been highlighted in the scientific literature. The charge of this task group was to recommend consistency tests designed to be performed by a medical physicist or a radiologic technologist under the direction of a medical physicist to identify problems with an imaging system that need further evaluation by a medical physicist, including a fault tree to define actions that need to be taken when certain fault conditions are identified. The focus of this final report is the ongoing QC process, including rejected image analysis, exposure analysis, and artifact identification. These QC tasks are vital for the optimal operation of a department performing digital radiography.


Asunto(s)
Intensificación de Imagen Radiográfica/normas , Acceso a la Información , Animales , Artefactos , Calibración , Recolección de Datos/métodos , Recolección de Datos/normas , Árboles de Decisión , Personal de Salud , Física Sanitaria/instrumentación , Física Sanitaria/métodos , Física Sanitaria/normas , Control de Calidad , Dosis de Radiación , Intensificación de Imagen Radiográfica/instrumentación , Intensificación de Imagen Radiográfica/métodos , Radiología/instrumentación , Radiología/métodos , Radiología/normas
20.
US Army Med Dep J ; : 83-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26276950

RESUMEN

Preventive Medicine Specialists (military occupational specialty [MOS] 68S) with the health physics specialist (N4) qualification identifier possess a unique force health protection skill set. In garrison, they ensure radiation exposures to patients, occupational workers and the public from hospital activities such as radioisotope therapy and x-ray machines do not to exceed Federal law limits and kept as low as reasonably achievable. Maintaining sufficient numbers of health physics specialists (HPSs) to fill authorizations has been a consistent struggle for the Army Medical Department due to the rigorous academic requirements of the additional skill identifier-producing program. This shortage has limited MOS 68SN4 deployment opportunities in the past and prevented medical planners from recognizing the capabilities these Soldiers can bring to the fight. In 2014, for the first time, HPSs were sourced to deploy as an augmentation capability to the 172nd Preventive Medicine Detachment (PM Det), the sole PM Det supporting the Combined Joint Operations Area-Afghanistan. Considerable successes in bettering radiation safety practices and improvements in incident and accident response were achieved as a result of their deployment. The purposes of this article are to describe the mission services performed by HPSs in Afghanistan, discuss the benefits of deploying HPSs with PM Dets, and demonstrate to senior medical leadership the importance of maintaining a health physics capability in a theater environment.


Asunto(s)
Física Sanitaria , Protección Radiológica/métodos , Asignación de Recursos , Campaña Afgana 2001- , Física Sanitaria/métodos , Física Sanitaria/organización & administración , Historia del Siglo XXI , Humanos , Medicina Militar/métodos , Medicina Militar/organización & administración , Monitoreo de Radiación/métodos , Asignación de Recursos/métodos , Asignación de Recursos/organización & administración , Estados Unidos , Recursos Humanos
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