Radiological Physics Research Articles

Establishment of local diagnostic reference levels for typical radiography examinations in the west region of Croatia

Majority of health institutions in Croatia do not have medical physicists in diagnostic radiology. Regarding this, in the west region of Croatia collaboration between public health institution and University Hospital Rijeka was initiated in 2015. Quality Assurance program was implemented in these public health institutions during 2015 and 2016 and the next step was to assess patient doses for the most frequent X-ray examinations. This included five public health institutions: 1 university hospital, 1 general hospital, 1 special hospital, 2 public health institutions with 13 facilities. The aim of this study was to carry out assessment of patient doses and to establish local diagnostic reference levels of entrance surface air kerma for every institution for six most frequent X-ray examinations. Also, local diagnostic reference levels for the whole west region of Croatia were established and compared with the national diagnostic reference levels and latest published data. Median entrance surface air kerma values for thorax PA, thorax LAT, cervical spine AP, thoracic spine AP, lumbar spine AP, pelvis AP and sinuses are 0.14 mGy, 0.50 mGy, 0.52 mGy, 1.50 mGy, 2.52 mGy, 2.03 mGy, and 1.03 mGy, respectively. Diagnostic reference levels proposed for our region were comparable with other studies.

Introduction of the Doi Award and MCA of Radiological Physics and Technology in 2018

Introduction of the Doi Award and MCA of Radiological Physics and Technology in 2018

Looking Back on the 10th Anniversary of Radiological Physics and Technology(RPT)

Looking Back on the 10th Anniversary of Radiological Physics and Technology(RPT)

65 DQPRM trainees welcome in EAP: APHM experience

Introduction DQPRM (Qualification diploma in Radiological and Medical Physics) students have theoretical courses at INSTN (National Institute of Nuclear Sciences and Technologies) for 6 months and complete their training with a 22-months hospital internship in an institution named Principal Home (EAP), in order to learn and validate the skills required for their future career of medical physicist. The internship duration is divided into different branches of activity that are mainly radiotherapy, radiology and nuclear medicine. Trainees are supervised by experimented medical physicists in each domain. Methods Before their arrival, students are invited to contact the person in charge of their reception at the EAP, and organize a first visit of the center. Upon arrival, after having completed the administrative steps (medical approval for work, blouses, meal card, computer access, …), trainees are invited to participate to a full meeting, letting them meet the whole physics team. At this time, the welcome book, previously sent, is detailed. It describes the Physics unit, organization of as well as the radiotherapy and medical imaging departments. During this meeting, the organization of the internship is explained and an annual planning is defined on the different parts. This organization allows a fair time distribution between participation in clinical routine and the completion of activity sheets supervised by different members of the team. This assignment allows optimal preparation and completion of the activities with the designated referent. Each supervisor sets with the trainees, the moment of the realization and validation of the skills. The students prepare the measurements to be done and the working method, and have the referent process validated. The measurements are made with or under supervision of the supervisor. This will validate the level of mastery of skills (not acquired, being acquired or acquired). Trainees also participate in the clinical routine. It’s important that they integrate perfectly the routine organization of the service (for example to participate in the morning staff, to integrate the planning of quality assurance of linear accelerators, to carry out pre-treatment checks, to carry out controls in medicine nuclear or estimate fetal exposure in radiology). This is a key step in learning the profession of medical physicists. Conclusions Effective and respectful management of DQPRMs is essential for the training in the field to be optimal, both humanly and scientifically. It’s meaningful that the two years of internship, which for many, are their first steps in medical physics, become a success.

Impact of a Monthly Compliance Review on Interventional Radiology Adverse Event Reporting

PurposeOur aims were to analyze the change in interventional radiology physician major adverse event (AE) reporting after initiation of a monthly morbidity and mortality (M&M) conference compliance review and to describe the association of procedure class and potentially preventable errors with major AE occurrence. MethodsIn late 2010, to motivate timely reporting, we instituted a structured monthly M&M conference review confirming whether each complication warranted institutional AE reporting and whether timely reporting had occurred. In this study, we retrospectively analyzed the M&M conference minutes over the subsequent 5 years. Logistic regression was used to model the change of AE reporting over time as well as the association of procedure class with the risk of an AE. Each AE was classified as to whether it seemed potentially preventable. ResultsThere were 46,660 patient encounters, 1,160 (2.5%) major and minor complications, and 462 (1.0%) reportable AEs. From 2011 to 2015, the percentage of reportable AEs reported increased from 67% to 98%. The number of months from initiation of the M&M conference review was a significant predictor of the likelihood of AE reporting (odds ratio 1.06, 95% confidence interval 1.04, 1.08, P < .0001). Procedure class was strongly associated with the risk of a reportable AE (P < .0001). At least 111 (24%) reportable AEs were potentially preventable. ConclusionsIncreasing AE reporting occurred after initiation of a monthly M&M conference compliance review. The incidence of reportable AEs was strongly associated with procedure class, and a significant percentage of these events were potentially preventable.

Application value of multiple imaging techniques in the MDCT combined with assessment of vascular invasion using a tumor-to-vessel contact computed tomography grading system in preoperative evaluation of pancreatic cancer

Application value of multiple imaging techniques in the MDCT combined with assessment of vascular invasion using a tumor-to-vessel contact computed tomography grading system in preoperative evaluation of pancreatic cancer

The Physician Payment Sunshine Act: Evaluating Industrial Payments in Radiology

The characterization of payments made to physicians by pharmaceutical companies, device manufacturers, and group purchasing organizations is crucial for assessing potential conflicts of interest and their impact on practice patterns. This study examines the compensation received by general radiologists (GR) in the United States, as well as radiologists in the following five subspecialties: body imaging, neuroradiology, pediatric radiology, nuclear radiology and radiological physics, and vascular and interventional radiology. Data were extracted from the Open Payments database for radiology subspecialists in the United States who received installments in calendar year 2015 from pharmaceutical and device manufacturing companies. In 2015, a total of $43,685,052 was paid in 65,507 payments (mean $667/payment; median $32/payment) to radiologists, including 9826 GR, 362 body imaging radiologists, 479 neuroradiologists, 127 pediatric radiologists, 175 physicians in nuclear radiology and radiological physics, and 1584 vascular and interventional radiologists. Payments were unequally distributed across these six major subspecialties of radiology (p < 0.01), with GR receiving the largest number of total payments (44,695), and neuroradiologists receiving significantly higher median payments than any other subspecialty ($80 vs $32 for all radiologists; p < 0.01). Medtronic Neurovascular was the single largest payer to all radiologists combined. Commercial entities make substantial payments to radiologists, with a significant variation in payments made to the different radiology subspecialties. While the largest number of total payments was made to GGR, the highest median payments were made to neuroradiologists, and significant dispersion in these payments was seen across different geographic regions. The impact of these payments on practice patterns remains to be elucidated.

Teaching Radiology Physics Interactively with Scientific Notebook Software

The goal of this study is to demonstrate how the teaching of radiology physics can be enhanced with the use of interactive scientific notebook software. We used the scientific notebook software known as Project Jupyter, which is free, open-source, and available for the Macintosh, Windows, and Linux operating systems. We have created a scientific notebook that demonstrates multiple interactive teaching modules we have written for our residents using the Jupyter notebook system. Scientific notebook software allows educators to create teaching modules in a form that combines text, graphics, images, data, interactive calculations, and image analysis within a single document. These notebooks can be used to build interactive teaching modules, which can help explain complex topics in imaging physics to residents.

IMPLEMENTATION OF QUALITY ASSURANCE PROGRAM IN RADIOGRAPHY-2-YEAR EXPERIENCE OF COLLABORATION WITH PUBLIC HEALTH INSTITUTIONS IN WEST REGION OF CROATIA.

Quality Assurance program on using ionizing radiation is mandatory in all EU member states but this is still not implemented in most facilities in Croatia mostly because of a lack of medical physicists in diagnostic radiology. Since public health institutions in Croatia do not employ medical physicists in diagnostic radiology, collaboration between these institutions in west region of Croatia with Clinical Hospital Center Rijeka (CHC) was initiated during the year 2015. Physicists from CHC Rijeka performed periodical Quality Control (QC) tests and were included in optimization process. Results of QC tests during the period of 2 years showed a lot of improvements-equipment is maintained more frequently, some old units were replaced with new ones and all institutions acquired QC equipment so radiographers could perform daily and monthly QC tests. All these activities showed that medical physics support in radiology departments is necessary and can improve clinical practice.

Shanghai Pulmonary Hospital Experts Consensus on the Management of Ground-Glass Nodules Suspected as Lung Adenocarcinoma (Version 1)

随着胸部计算机断层扫描（computed tomography, CT）检查，尤其是低剂量薄层CT筛查项目在中国的广泛开展，越来越多的无症状肺部磨玻璃结节（ground-glass nodules, GGNs）被发现。虽然国内及国际上已发布了一系列针对肺部GGNs的指南，但是这些指南的撰写者多来自呼吸、肿瘤及影像专业，可能缺乏对现代微创胸外科的充分认识，造成外科手术在肺部GGNs诊治中的作用不明确，甚至被低估；而且，肺部肿瘤相关的各学科对于早期肺癌，尤其是浸润前病变的处理也缺乏统一规范。因此，基于国内外现有文献及上海市肺科医院多年积累的经验，上海市肺科医院撰写了此诊疗共识。本共识推荐对于疑似肺腺癌的GGNs进行多学科评估，依据诊断，选择合理的处置方式。对于疑似原位腺癌，推荐进行胸部薄层CT随访，或在特定情况下进行不超过肺段切除的限制性肺切除；对于疑似微浸润腺癌，推荐进行限制性肺切除或肺叶切除；对于疑似浸润性腺癌，建议依据病灶是否含有磨玻璃成分、位置、大小、个数及患者躯体情况选择合理的手术方式；而肺多发结节的处理原则推荐为主病灶优先，兼顾次要病灶，综合选择治疗方案。

Obtaining an Impact Factor: Radiological Physics and Technology

Obtaining an Impact Factor: Radiological Physics and Technology

3:54 PM Abstract No. 127 Preliminary assessment of hospital staff body and hand radiation exposure during Y90 radioembiolization dose preparation and administration

The safe use of ytrrium-90 (Y90) for radioembolization requires that all staff involved have a firm understanding of the radiation safety aspects of the devices. Two types of Y90 liver therapies are currently available, each with different method of preparation and administration. Although widely used, there is minimal data on the radiation exposure to staff performing these procedures. We present preliminary data on radiation exposure to staff involved with Y90 radioembolization therapies. Measurements of body (5 SIR, 5 Thera) and hand doses (6 SIR, 13 Thera) for interventional radiology physicians and nuclear medicine technologists were recorded during TheraSphere (Biocompatibles, Farnham, UK) and SIR-Spheres (Sirtex, North Sydney, AU) patient treatments. Evaluation of hand exposure used Saturn TLD rings (Landauer, Glenwood, IL) worn on both hands during Y90 preparation and administration. Multiple treatments were recorded on a single ring and the average taken over the number of treatments for each therapy. Body exposure was measured using a Rados Rad60 electronic radiation dosimeter (Mirion, Smyrna, GA) with the meter located underneath lead aprons for physicians, and on the abdomen of nuclear medicine technologists. Total hand doses for all TheraSphere procedures remained below 10 mrem, the lowest measurable dose for the TLDs used in this study. SIR-spheres hand doses averaged 12 mrem and 124 mrem per procedure for physician administration and technologist preparation, respectively. Body doses for technologists handling SIR-Spheres averaged 0.16 mrem ± 0.05 and 0.02 ± 0.04 mrem for TheraSpheres. Body doses for physicians measured 0.1 mrem ± 0.1 mrem for SIR-spheres and were too low to measure for TheraSphere. TheraSphere and SIR-Spheres therapies have generally low radiation exposure to hospital personnel when used in routine clinical cases. More data is needed to provide greater statistical significance of these preliminary results.

Bridging the Gap: Identifying Global Trends in Gender Disparity Among the Radiology Physician Workforce

Women make up half of American medical school graduates, but remain underrepresented among radiologists. This study sought to determine whether workforce gender disparities exist in other countries, and to identify any country-specific indices associated with increased female representation. In this cross-sectional study, 95 professional radiology organizations in 75 countries were contacted via email to provide membership statistics, including proportion of female members, female members aged 35 or under, and women in society leadership positions. Country-specific metrics collected included gross domestic product, Gini index, percent female medical school enrollment, and Gender Development Index for the purposes of univariate multiple regression analysis. Twenty-nine organizations provided data on 184,888 radiologists, representing 26 countries from Europe (n = 12), North America (n = 2), Central/South America (n = 6), Oceania (n = 2), Asia (n = 3), and Africa (n = 1) for a response rate of 34.7% (26/75). Globally, 33.5% of radiologists are female. Women constitute a higher proportion of younger radiologists, with 48.5% of radiologists aged 35 or under being female. Female representation in radiology is lowest in the United States (27.2%), highest in Thailand (85.0%), and most variable in Europe (mean 40.1%, range 28.8%-68.9%). The proportion of female radiologists was positively associated with a country's Gender Development Index (P = .006), percent female medical student enrollment (P = .001), and Gini index (P = .002), and negatively associated with gross domestic product (P = .03). Women are underrepresented in radiology globally, most notably in the United States. Countries with greater representation of women had higher gender equality and percent female medical school enrollment, suggesting these factors may play a role in the gender gap.

Introduction of the Doi Award and MCA of Radiological Physics and Technology in 2018

Introduction of the Doi Award and MCA of Radiological Physics and Technology in 2018

Abstract TP319: Early Feeding Post G-tube Insertion is Safe in Stroke Patients

Introduction: Initiation of tube feeding (TF) via gastrostomy tube (G-tube) after insertion in dysphagic stroke patients is often delayed per physician preference with delayed feeding (DF) initiated at 12-24 hours being a common practice. Guidelines suggest that initiation of G-tube feeding (EF) within 4 hours after insertion is safe and does not lead to more complications. The stroke and interventional radiology (IR) physicians at a comprehensive stroke center agreed to an EF guideline in April 2016 and changed the post-insertion G-tube feed initiation time in all stroke patients from 24 hours to 6 hours. A year after, we conducted this retrospective study to understand the impact of EF guideline on TF timings. Methods: All stroke patients that had G-tubes placed by IR between April 2015 and April 2017 were eligible for inclusion in the study. Patients with non-stroke diagnoses were excluded, as were those whose tube feeds were never initiated. In addition to TF timings, data regarding complications and reasons for guideline deviation were recorded. Descriptive analyses were done for continuous and categorical variables. Results: Compared to pre-protocol patients (n= 37), the TF initiation time in EF group (n= 47, range 5-51 hours) decreased by 11.5 hours after institution of EF guidelines (25.8 hrs vs 14.2 hrs, p &lt; 0.0001 ). Only eight patients (17%) had TFs started by 6 hours, while twenty-one (44%) had TF started by 10 hours. There was a nonsignificant increase in complications after protocol initiation: 8 patients (17%) in the protocol group vs 4 (11%) in the pre-protocol group (OR = 1.69, 0.47 - 6.13, 95% CI). In five of eight patients in the protocol group who developed complications, TFs were initiated after 12 hours. No death was noted on account of EF. No significant difference in length of stay was noted. Delays in TF initiation were mostly due to failure to write appropriate orders (n=8) and less often for worsening in clinical status due to insertion related (n=2) or unrelated (n=2) complications. Conclusions: TF initiation time can be significantly improved with institution of an EF guideline without any significant increase in complications. With education, guideline compliance can be improved further.

Tutorials in radiotherapy physics: Advanced topics with problems and solution. Author: PatrickN. McDermott, CRC Press, Taylor &amp; Francis Group, Boca Raton, FL, 2016. Paperback 302 pp. Price: $99.95. ISBN 9781482251678.

This book is intended to be a textbook with systematic mathematical descriptions of five advanced topics in medical physics. These topics include Physics in Medical Linacs, Proton Therapy, Convolution and Superposition Dose Computation Algorithms, Dose Calculations with Boltzmann Transport Equation, Tumor Control and Normal Tissue Complication Probability Models. The book establishes fundamental understandings and introduces current advancements in these topics. It contains a great number of high quality images and mathematical equations to enhance the reading experience. There are also problems and questions at the end of each chapter. It should be of interests to the medical physics community. The advanced topics covered in this book are not covered well in traditional medical physics textbooks. This book is written as a synthesis from a large variety of sources so the readers can learn the topics from the book and have the capability to explore further readings. The topics in the book are developed with consistent mathematical notations from fundamental physics knowledge and equations. The topics covered in this book are self-contained study modules which can be used as textbook for graduate medical physics program, physics residency program, or self-study materials for practicing medical physicists. They are advanced topics for medical physicists to understand the current trend and developments in the field. The contents are well-written and illustrated for readers to develop quantitative understanding of the material. Due to its extensive content of the mathematical formulation in each topic, the prerequisite of the book is a bachelor's degree in physics and a graduate-level course in radiological physics. The book covers five topics in medical physics, which are independent of each other. The first chapter discusses the physics of electron acceleration in medical linacs. Maxwell's equation and boundary conditions are applied to develop quantitative understanding of various designs of waveguides. The content focuses on the derivations relevant to the electron acceleration mechanisms exploited by the medical linacs. The second chapter, proton therapy, introduces the history and treatment machine developments of several vendors. The focus is on the physics of the proton accelerators and transport subsystems. The pros and cons of the double scattering and the pencil beam scanning modalities are illustrated. It however does not provide in-depth details on proton treatment planning techniques. Chapter three discusses the popular photon convolution and superposition dose calculation algorithms, which are adopted by most of the commercial treatment planning systems. The major steps of these model-based algorithms are introduced in this chapter, including the calculations of incident energy fluence, kernels, medium heterogeneities and additional electron contaminations. The dose calculation algorithm by Boltzmann transport equation is gaining popularity in the medical physics community. Chapter four illustrates the deterministic transport approach to dose calculations for both photons and electrons. A particular helpful topic on Tumor Control and Normal Tissue Complication Probability Models is covered in chapter five. Not only the basic, but more advanced discussions on serial or parallel organ NTCP model and heterogeneity tumor control model formulations are addressed. The best aspect of this book is that it presents each topic from the perspective of fundamental physics principles and adheres to rigorous standards of mathematical presentation. It avoids superficial and qualitative presentation of core principles. Instead, the details are derived using consistent mathematical notation to facilitate the reading and understanding. This feature is unique from other available textbooks. The topics are all self-contained and up-to-date with the current state of technology development. The entire book provides a concise, easy to follow, bottom up approach to the topics. It is well-written and pleasant to read. The complete and systematic mathematical derivations in the book require the readers to possess a level of physics and mathematics background, including vector calculus, differential equations, advanced undergraduate electricity and magnetism, and matrix algebra to completely follow the materials. Nonetheless, it is a great textbook for individuals to acquire understanding of these advanced topics on a fundamental level. Wei Zou is an assistant professor at the University of Pennsylvania, Perelman School of Medicine, Department of Radiation Oncology. Her research interests are advanced techniques in radiation therapy and proton radiotherapy.

Recent Review Articles in Radiological Physics and Technology

Recent Review Articles in Radiological Physics and Technology

The Process and the Memory of Starting the Journal of Radiological Physics and Technology

The Process and the Memory of Starting the Journal of Radiological Physics and Technology

Correlation between obesity and fat-infiltrated axillary lymph nodes visualized on mammography.

Using screening mammography, this study investigated the association between obesity and axillary lymph node (LN) size and morphology. We conducted a retrospective review of 188 females who underwent screening mammography at an academic medical centre. Length and width of the LN and hilum were measured in the largest, mammographically visible axillary node. The hilo-cortical ratio (HCR) was calculated as the hilar width divided by the cortical width. Measurements were performed by a board certified breast radiologist and a resident radiology physician. Inter-rater agreement was assessed with Pearson correlation coefficient. We performed multivariable regression analysis for associations of LN measurements with body mass index (BMI), breast density and age. There was a strong association between BMI and LN dimensions, hilum dimensions and HCR (p < 0.001 for all metrics). There was no significant change in cortex width with increasing BMI (p = 0.15). Increases in LN length and width were found with increasing BMI [0.6 mm increase in length per unit BMI, 95% CI (0.4-0.8), p < 0.001 and0.3 mm increase in width per unit BMI, 95% CI(0.2-0.4), p < 0.001, respectively]. Inter-rater reliability for lymph node and hilum measurements was 0.57-0.72. We found a highly significant association between increasing BMI and axillary LN dimensions independent of age and breast density with strong interobserver agreement. The increase in LN size was driven by expansion of the LN hilum secondary to fat infiltration. Advances in knowledge: This preliminary work determined a relationship between fat infiltrated axillary lymph nodes and obesity.

Abstract ID: 210 Using Monte Carlo simulation as an experimental tool for training of medical physicists in a diagnostic radiological physics residency program

The usefulness of Monte Carlo for solving problems in radiation transport has allowed many applications in the medical physics field. Particularly as a teaching aid, Monte Carlo can be used to demonstrate previously the effects of the interaction of radiation with matter, which can be switched on and off to observe its influence under different conditions of irradiation and geometry. Based on that, this study reports an experience with using of Monte Carlo simulation for training of medical physicists during a residency program in diagnostic radiological physics. The approach was implemented in the EGSnrc Monte Carlo code system [1] to an understanding of the factors affecting quality image and to reduction of patient exposure in radiographic examinations performed in various areas of diagnostic radiology. All simulation conditions were based on the cases provided by the Report of AAPM Task Group 195 [2] . Physical characteristics of primary and scattered X-ray spectra, quantities as radiation dose and contrast-to-noise ratio of imaging systems, among others, could be studied under different radiological conditions by changing the input parameters in the simulation. Results obtained with this approach facilitate resident’s experimental learning curve, contributing to anticipate the discussion about practical problems that would be found in clinical environment. The use of Monte Carlo simulations with educational purposes demonstrated be an efficient and flexible tool for training of medical physicists in a residency program.