Construcción y validación de un fantoma torácico pediátrico asequible para optimizar la dosis / Low-cost chest paediatric phantom for dose optimisation: construction and validation

Introducción y objetivosPara llevar a cabo estudios de optimización de dosis, el fantoma de imagenología debe ser adecuado para evaluar la calidad de la imagen. El coste de los fantomas de gama alta suele ser prohibitivo, por lo que es necesario hallar un método de construcción asequible que emplee sustitutos tisulares que sean razonablemente fáciles de obtener.Materiales y métodosSe realizaron cálculos teóricos de las características radiológicas de cada uno de los pulmones, el hueso cortical y los tejidos blandos con el fin de elegir el sustituto adecuado; para ello, se eligieron el corcho, el cloruro de polivinilo (PVC) y el agua, respectivamente. La validación consistió, en primer lugar, en la medición de las unidades Hounsfield (UH) de tomografía computarizada (TC) de los tejidos de un paciente real y su posterior comparación con las anatomías correspondientes en el fantoma construido. En segundo lugar, se obtuvieron los valores de relación señal/ruido (S/R) y de relación contraste/ruido (C/R) para evaluar la calidad de las imágenes generadas a partir del fantoma construido y comparar sus tendencias con un fantoma válido utilizando diferentes parámetros de exposición (valores pico de kilovoltaje [kVp] y miliamperios por segundo [mAs]).ResultadosPartiendo de los cálculos teóricos, las diferencias porcentuales exhibieron una precisión elevada en los sustitutos tisulares al simular los tejidos de un paciente real; con PVC fue de ≥ 5,78%, con corcho ≥ 4,46% y con agua ≥ 5%. La diferencia porcentual (UH de TC) entre el pulmón y el hueso cortical y sus sustitutos tisulares equivalentes fue de 10,44% y de 0,53 a 3,17%, respectivamente. Se encontraron fuertes correlaciones positivas para la S/R al variar tanto los valores de kVp (0,79) como de mAs (0,65). Por el contrario, se halló que la fuerza de correlación de los valores de la C/R era moderada al cambiar los valores de kVp (0,58) y mAs (0,53).(AU)

Introduction and ObjectivesIn order to perform chest dose optimisation studies, the imaging phantom should be adequate for image quality evaluation. Since high-end phantoms are cost prohibitive, there is a need for a low-cost construction method with fairly available tissue substitutes.Materials and MethodsTheoretical calculations of radiological characteristics were performed for each of lung, cortical bone and soft tissues in order to choose appropriate substitute, then, cork, P.V.C. (Polyvinyl Chloride) and water were chosen, respectively. Validation included, firstly, measuring CT Hounsfield Units (HU) of a real patient's tissues then compared against their corresponding anatomies in the constructed phantom. Secondly, Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) values were acquired in this study to evaluate the quality of images generated from the constructed phantom, then, compare their trends with a valid phantom under different exposure parameters (kVp and mAs).ResultsFrom theoretical calculations, the percentage differences showed high accuracy of tissue substitutes when simulating real patient tissues; P.V.C. was ≥ 5.78%, cork was ≥ 4.46% and water ≥ 5%. The percentage difference (CT HU) between lung and cortical bone and their equivalent tissue substitutes were 10.44% and 0.53%-3.17%, respectively. Strong positive correlations were found for SNR when changing both kVp (0.79) and mAs (0.65). While the correlation strength of CNR values were found to be moderate when changing both kVp (0.58) and mAs (0.53).ConclusionsOur low-cost phantom approved through CT HU that their materials replicate the radiological characteristics of real one-year-old child while SNR and SNR correlations confirmed its applicability in imaging and optimisation studies.(AU)

QuantImage v2: a comprehensive and integrated physician-centered cloud platform for radiomics and machine learning research.

BACKGROUND: Radiomics, the field of image-based computational medical biomarker research, has experienced rapid growth over the past decade due to its potential to revolutionize the development of personalized decision support models. However, despite its research momentum and important advances toward methodological standardization, the translation of radiomics prediction models into clinical practice only progresses slowly. The lack of physicians leading the development of radiomics models and insufficient integration of radiomics tools in the clinical workflow contributes to this slow uptake. METHODS: We propose a physician-centered vision of radiomics research and derive minimal functional requirements for radiomics research software to support this vision. Free-to-access radiomics tools and frameworks were reviewed to identify best practices and reveal the shortcomings of existing software solutions to optimally support physician-driven radiomics research in a clinical environment. RESULTS: Support for user-friendly development and evaluation of radiomics prediction models via machine learning was found to be missing in most tools. QuantImage v2 (QI2) was designed and implemented to address these shortcomings. QI2 relies on well-established existing tools and open-source libraries to realize and concretely demonstrate the potential of a one-stop tool for physician-driven radiomics research. It provides web-based access to cohort management, feature extraction, and visualization and supports "no-code" development and evaluation of machine learning models against patient-specific outcome data. CONCLUSIONS: QI2 fills a gap in the radiomics software landscape by enabling "no-code" radiomics research, including model validation, in a clinical environment. Further information about QI2, a public instance of the system, and its source code is available at https://medgift.github.io/quantimage-v2-info/ . Key points As domain experts, physicians play a key role in the development of radiomics models. Existing software solutions do not support physician-driven research optimally. QuantImage v2 implements a physician-centered vision for radiomics research. QuantImage v2 is a web-based, "no-code" radiomics research platform.

Pediatric Applications of Photon-Counting Detector CT.

Photon-counting detector (PCD) CT represents the most recent generational advance in CT technology. PCD CT has the potential to reduce image noise, improve spatial resolution and contrast resolution, and provide multispectral capability, all of which may be achieved with an overall decrease in the radiation dose. These effects may be used to reduce the iodinated contrast media dose and potentially obtain multiphase images through a single-acquisition technique. The benefits of PCD CT have previously been shown primarily in phantoms and adult patients. This article describes the application of PCD CT in children, as illustrated by clinical examples from a commercially available PCD CT system.

Desarrollo de algoritmo clínico para el diagnóstico de tumores del espacio parafaríngeo. Revisión sistemática / The development of a clinical algorithm for the diagnosis of tumours in the parapharyngeal space. A systematic review

Introducción: El espacio parafaríngeo (EPF) es definido como un espacio profundo, situado alrededor de la faringe superior, con forma de pirámide invertida. Los tumores primarios de esta región son poco frecuentes, representando el 0,5% de las neoplasias de la cabeza y el cuello, y la mayoría son benignos. El objetivo de este trabajo es proponer un nuevo algoritmo de estudio basado en una revisión sistemática y en nuestra experiencia. Material y método: Se realizó un trabajo transversal y analítico a través de la revisión de historias clínicas de nuestro hospital. Se incluyeron pacientes con tumores del espacio parafaríngeo operados desde enero de 2010 a diciembre de 2019 con revisión en Pubmed de estudios de los últimos 5años. Tuvimos en cuenta signos clínicos, métodos diagnósticos, diagnóstico presuntivo y hallazgos histopatológicos. El análisis estadístico se realizó con el software STATA v.14. Resultados: Se incluyeron 53 casos nuestros y 1.392 de la revisión. El algoritmo clínico mostró una sensibilidad del 76,4% y una especificidad del 96,3%, con una AUC de 0,57 para el diagnóstico. Discusión: Los exámenes radiológicos complementarios son imprescindibles en el diagnóstico topográfico del tumor. La angio-RNM vincula el tejido de origen de los tumores y aporte la mayor certeza diagnóstica. La PAAF tiene algunas desventajas en EPF, pero es útil en algunos pacientes. Conclusión: El algoritmo propuesto contribuye a obtener resultados excelentes en el manejo de estos tumores debido a que resultó ser eficaz en el diagnóstico, y ello permite mejorar la planificación quirúrgica.(AU)

Introduction: Parapharyngeal space (PPS) is defined as a deep space, located around the upper pharynx, in the shape of an inverted pyramid. Primary tumours in this region are rare, accounting for 0.5% of head and neck neoplasms, and most are benign. The objective of this study is to propose a new study algorithm based on a systematic review and our experience. Materials and methods: A cross-sectional and analytical study was carried out through review of the clinical records of our hospital. Patients with tumours of the parapharyngeal space operated from January 2010 to December 2019 and a systematic review of Pubmed studies from the last 5years were included. We considered clinical signs, diagnostic methods, presumptive diagnosis and histopathological findings. Statistical analysis was performed with STATA v.14 software. Results: 53 of our cases and 1392 from the review were included. The clinical algorithm showed a sensitivity of 76.4% and a specificity of 96.3%, with an AUC of 0.57 for diagnosis. Discussion: Complementary radiological examinations are essential in the topographic diagnosis of the tumour. Angio-MRI links the tissue of origin of the tumours and provides the highest diagnostic certainty. FNA has some disadvantages in PPS, but it is useful in some patients. Conclusion: The proposed algorithm contributes to obtaining excellent results in the management of these tumours because it turned out to be effective in diagnosis, and this enables improved surgical planning.(AU)

Analyzing medical device connectivity and its effect on cyber security in german hospitals.

BACKGROUND: Modern healthcare devices can be connected to computer networks and many western healthcare institutions run those devices in networks. At the same time, cyber attacks are on the rise and there is evidence that cybercriminals do not spare critical infrastructure such as major hospitals, even if they endanger patients. Intuitively, the more and closer connected healthcare devices are to public networks, the higher the risk of getting attacked. METHODS: To asses the current connectivity status of healthcare devices, we surveyed the field of German hospitals and especially University Medical Center UMCs. RESULTS: The results show a strong correlation between the networking degree and the number of medical devices. The average number of medical devices is 25.150, with a median of networked medical devices of 3.600. Actual key users of networked medical devices are the departments Radiology, Intensive Care, Radio-Oncology RO, Nuclear Medicine NUC, and Anaesthesiology in the group of UMCs. In the next five years, the usage of networked medical devices will increase significantly in the departments of Surgery, Intensive Care, and Radiology. We detected a strong correlation between the degree of connectivity and the likelihood of being attacked.The survey answers regarding the cyber security status reveal a lack of security basics in some of the inquired hospitals. We did discover successful attacks in hospitals with separated or subsidiary departments. A fusion of competencies on an organizational level facilitates the right behavior here. Most hospitals rated themselves predominantly positively in the self-assessment but also stated the usefulness of IT security insurance. CONCLUSIONS: Concluding our results, hospitals are already facing the consequences of omitted measures within their growing pool of medical devices. Continuously relying on historically grown structures without adaption and trusting manufactures to solve vectors is a critical behavior that could seriously endanger patients.

A built-up-type deformable phantom for target motion control to mimic human lung respiration.

Existing human lung-mimicking requirements in various radiology application fields have led to the development of many different phantoms. However, most are static apparatus designed for equipment calibration. Although there are a few dynamic phantoms that generate predefined motions, they have complicated mechanisms that hamper even simple modifications for various lung illness simulations. As a result, existing dynamic phantoms in which a target can be embedded normally generate rectilinear target motions with limited displacement. Nevertheless, volume changes in the human lungs during normal respiration are significant, and targets inside the lungs move along various random paths depending on their location, stiffness, and the properties of the surrounding tissues. In the present work, a novel phantom design is introduced and tested. The phantom mimics the human lung motion and its deformation is initiated by a diaphragm movement. The phantom provides a fairly large deformation and the capability to adjust target motion paths. The presented device has a simple mechanism that can be easily modified to generate various pulmonary diseases. To produce a large deformation by diaphragm compressive motion, polyurethane cubic blocks constitute the deformable part of the lung phantom and a tumor made with silicone is inserted in the structure. The assembled lung part is housed within an acrylic case that is filled with water. The phantom system consists of acrylic, plastic, and low-density polyurethane to minimize artifacts when it undergoes computed tomography (CT) scans. The lung part is organized with various density polyurethane blocks, making it possible to produce nonlinear motion paths of the tumor. The lung part is deformed by a silicon film that is driven by external hydraulic pressure. A finite element method simulation and two-dimensional target motion tests were performed to verify phantom performance. The functionality of the proposed phantom system was confirmed in a series of CT images.

Analysis of magnetic resonance imaging features of ovarian thecoma.

To investigate the magnetic resonance imaging (MRI) findings in ovarian thecoma and improve preoperative diagnostic accuracy.Retrospective analysis was performed on 45 patients with surgically and pathologically confirmed ovarian thecoma. Patients were grouped into those with maximum lesion diameter ≥5 cm and <5 cm. Diagnostic scores (up to 6 points) were evaluated on the basis of MRI performance.The ≥5 cm group contained 36 cases (cystic necrosis, 32 cases) with the following findings: T1WI: isointense signal, 22 cases; slightly hypointense signal, 14 cases; T2WI: isointense signal, 6 cases; slightly hypointense signal, 21 cases; slightly hyperintense signal, 9 cases; Diffusion-weighted imaging (DWI): hyperintense signal, 23 cases; mixed hyperintense signal, 13 cases; slight enhancement on dynamic enhanced scans; pelvic fluid accumulation, 31 cases. The diagnostic score evaluations yielded 6 points in 31 cases, 5 points in 1 case, 4 points in 2 cases, and 3 points in 2 cases. The <5 cm group contained 9 cases (cystic necrosis, 3 cases) with the following findings: T1WI: isointense signal, 3 cases; slightly hypointense signal, 6 cases; T2WI: isointense signal, 2 cases; slightly hypointense signal, 4 cases; slightly hyperintense signal, 3 cases; DWI, hyperintense signal; slight enhancement in 8 cases and significant enhancement in 1 case; pelvic fluid accumulation, 4 cases. The diagnostic score evaluations yielded 6 points in 3 cases, 5 points in 1 case, 4 points in 4 cases, and 3 points in 1 case. (iii) Incidence of pelvic fluid accumulation and cystic necrosis differed depending on the size of the lesion (P = .007, .000).Larger lesions show hyperintense or mixed hyperintense signals on DWI along with pelvic fluid and cystic necrosis; whereas, smaller lesions show a hyperintense signal on DWI, cystic necrosis is rare. MRI characteristics along with the patient age and laboratory findings can improve the accuracy of preoperative diagnosis of these lesions.

Radiology Residency Preparedness and Response to the COVID-19 Pandemic.

This article provides a guideline for radiology residency programs to prepare and respond to the impact of coronavirus disease 2019, by offering specific examples from three programs, and provides a list of resources for distance learning and maintaining well-being.

Artificial intelligence and the radiologist: the future in the Armed Forces Medical Services.

Artificial intelligence (AI) involves computational networks (neural networks) that simulate human intelligence. The incorporation of AI in radiology will help in dealing with the tedious, repetitive, time-consuming job of detecting relevant findings in diagnostic imaging and segmenting the detected images into smaller data. It would also help in identifying details that are oblivious to the human eye. AI will have an immense impact in populations with deficiency of radiologists and in screening programmes. By correlating imaging data from millions of patients and their clinico-demographic-therapy-morbidity-mortality profiles, AI could lead to identification of new imaging biomarkers. This would change therapy and direct new research. However, issues of standardisation, transparency, ethics, regulations, training, accreditation and safety are the challenges ahead. The Armed Forces Medical Services has widely dispersed units, medical echelons and roles ranging from small field units to large static tertiary care centres. They can incorporate AI-enabled radiological services to subserve small remotely located hospitals and detachments without posted radiologists and ease the load of radiologists in larger hospitals. Early widespread incorporation of information technology and enabled services in our hospitals, adequate funding, regular upgradation of software and hardware, dedicated trained manpower to manage the information technology services and train staff, and cyber security are issues that need to be addressed.

Development and evaluation of a mobile application for teaching Dental Radiology / Desenvolvimento e avaliação de aplicativo móvel para ensino de Radiologia Odontológica

This study aimed to develop and evaluatea smartphone applicationwith a web content managementtoolforthe study of periapical radiographic anatomy. Design thinking activities werecarried outto better understand the proposed problem.Then, a questionnaire wasapplied via Google Formsto44 dentalstudents to assist in the development of an Appfor the teaching of radiology. Then, thebeta version of theApp was evaluated in January 2019by 51undergraduate dentalstudentsby means ofsatisfaction and usability questionnaires.The Cronbach's alpha coefficientwas applied to these questionnairesandvalues above 0.7were obtained, demonstrating theirreliability. In the evaluationof the App, which was called APPOLO,that means App of learning online, 98.04% of the students affirmed that the available contentwas certainlyimportant. The number of images wasconsidered either satisfactoryor very satisfactory by 94.19% of the participants, and 100% of them judged the qualityof theimages also satisfactoryor very satisfactory. The majority ofthe participants(94.11%)feltmotivated to complement their study using this type of methodology.The classification easy and very easy was attributed to the metricsusabilityby 98.04% of the participants, access to offered contentsby 100%of the participants, and access to the textsby 98%of the participants.The APPOLOApp provedto be practical and easy to understand, navigate, and use, as was considered a potential aid tosupport the teaching ofdental radiology students (AU).

Este estudo teve como objetivo desenvolver e avaliar um aplicativo para smartphone com uma ferramenta de gerenciamento de conteúdo da web para o estudo da anatomia radiográfica periapical. Atividades de Design Thinking foram realizadas para melhor compreender o problema proposto pelo grupo de pesquisa. Em seguida, foi realizadauma pesquisa exploratória via Google Forms com 44 estudantes de Odontologia, aplicando-se um questionário para auxiliar no desenvolvimento de um aplicativo para ensino de Radiologia. Com o aplicativo na versão inicial, beta, foram aplicados questionários de satisfação e usabilidade com 51 alunos do curso de graduação em Odontologia, para avaliação do App. O coeficiente alfa de Cronbach foi aplicado a esses questionários e valores acima de 0,7 foram obtidos, demonstrando sua confiabilidade. Na avaliação do aplicativo, denominado APPOLO, que significa "App of learning online", 98,04% dos alunos afirmaram que o conteúdo disponível era certamente importante. A quantidade de imagens foi considerada entre satisfatórias e muito satisfatórias por 94,19% dos participantes e 100% deles julgaram a qualidade das imagens também satisfatória ou muito satisfatória. A maioria dos participantes (94,11%) sentiu-se motivada em complementar seu estudo com esse tipo de metodologia. Quanto a usabilidade do aplicativo, 98,04% classificaram entre fácil e muitofácil o seu manuseio, 100% o acesso aos conteúdos ofertados e 98% o acesso aos textos, seguindo essa mesma métrica. O aplicativo APPOLO demonstrou ser prático, de fácil entendimento, navegação e utilização, e revelou auxiliar no apoio ao ensino dos alunosda disciplina de Radiologia Odontológica (AU).

Pathfinders in oncology from the end of the 19th century to the first description of Ewing sarcoma.

During the period 1884 to 1922, the only option in cases of operable cancers was radical surgery, and only a minority of patients were cured. Sporadic attempts were made to treat inoperable cancer patients with bacterial toxins; however, with the discovery of x-ray and radium, the era of radiation treatment as an alternative to surgery began. The discovery of transmissible cancers and experimental growth of cancer cells offered new information and not only led to a better understanding of the cellular composition of cancers but also yielded important information that ultimately paved the way to chemotherapy. These efforts also advanced the understanding of the pathogenesis of tumors and induced new clinical and pathologic classifications and subspecializations. It is important to emphasize that many of the initiatives and discoveries made in Europe in the second half of the 19th century were first put into clinical practice in the United States during the first 2 decades of the 20th century, including the use of x-ray and radium for irradiation and as diagnostic tools. All things considered, the progress made between 1884 and 1922 came about through the hard work of many eminent individuals; however, there were 7 foresighted pathfinders (3 surgeons, 2 pathologists, 1 internist, and 1 physicist) who-despite their widely diverse backgrounds, personalities, and expertise-made remarkable contributions to oncology to an extent that is still felt today.

Practical recommendations for the application of DE 59/2013.

The changes introduced with Council Directive 2013/59/Euratom will require European Member States adapt their regulations, procedures and equipment to the new high standards of radiation safety. These new requirements will have an impact, in particular, on the radiology community (including medical physics experts) and on industry. Relevant changes include new definitions, a new dose limit for the eye lens, non-medical imaging exposures, procedures in asymptomatic individuals, the use and regular review of diagnostic reference levels (including interventional procedures), dosimetric information in imaging systems and its transfer to the examination report, new requirements on responsibilities, the registry and analysis of accidental or unintended exposure and population dose evaluation (based on age and gender distribution). Furthermore, the Directive emphasises the need for justification of medical exposure (including asymptomatic individuals), introduces requirements concerning patient information and strengthens those for recording and reporting doses from radiological procedures, the use of diagnostic reference levels, the availability of dose-indicating devices and the improved role and support of the medical physics experts in imaging.

Determination of a tactile feedback strategy for use in robotized percutaneous procedures.

Remote manipulation in robotized percutaneous procedures can offer increased safety to radiologists as well as patients. Providing feedback to the radiologist on needle-tissue interactions is however mandatory in addition to the medical images. A tactile feedback strategy is developed in this paper. Two types of information are considered: tissue puncture and nature of tissues. A haptic device is developed for that purpose, using a tactile display to provide information. Adequate signals are identified experimentally, with analysis of reaction times and the ability to discriminate one information from the other.

An audit of licensed Zimbabwean radiology equipment resources as a measure of healthcare access and equity

Introduction: approximately two-thirds of the world's population has no access to diagnostic imaging. Basic radiological services should be integral to universal health coverage. The World Health Organization postulates that one basic X-ray and ultrasound unit for every 50000 people will meet 90% of global imaging needs. However, there are limited country-level data on radiological resources, and little appreciation of how such data reflect access and equity within a healthcare system. The aim of this study was a detailed analysis of licensed Zimbabwean radiological equipment resources.Methods: the equipment database of the Radiation Protection Authority of Zimbabwe was interrogated. Resources were quantified as units/million people and compared by imaging modality, geographical region and healthcare sector. Zimbabwean resources were compared with published South African and Tanzanian data.Results: public-sector access to X-ray units (11/106 people) is approximately half the WHO recommendation (20/106 people), and there exists a 5-fold disparity between the least- and best-resourced regions. Private-sector exceeds public-sector access by 16-fold. More than half Zimbabwe's radiology equipment (215/380 units, 57%) is in two cities, serving one-fifth of the population. Almost two-thirds of all units (243/380, 64%) are in the private sector, routinely accessible by approximately 10% of the population. Southern African country-level public-sector imaging resources broadly reflect national per capita healthcare expenditure.Conclusion: there exists an overall shortfall in basic radiological equipment resources in Zimbabwe, and inequitable distribution of existing resources. The national radiology equipment register can reflect access and equity in a healthcare system, while providing medium-term radiological planning data

Observations And Experiments For The Definition Of A New Robotic Device Dedicated To CT, CBCT And MRI-Guided Percutaneous Procedures.

In this paper, we present the work achieved to define the robotic functionalities of interest for percutaneous procedures as performed in interventional radiology. Our contributions are twofold. First, a detailed task analysis is performed with workflow analysis of biopsies, one of the most frequent tasks, under three imaging modalities, namely CT, CBCT and MRI. Second, the functionalities of a robotic assistant are identified, and we analyze whether a single device can bring an added value during procedures in the three modalities while keeping the robotized workflow close to manual tasks, to minimize learning time and difficulty of use. Experimental analysis on CBCT is notably used to confirm the interest of the determined robotic functionalities.

Artificial Intelligence in Radiology: Current Technology and Future Directions.

Artificial intelligence (AI) has been heralded as the next big wave in the computing revolution and touted as a transformative technology for many industries including health care. In radiology, considerable excitement and anxiety are associated with the promise of AI and its potential to disrupt the practice of the radiologist. Radiology has often served as the gateway for medical technological advancements, and AI will likely be no different. We present a brief overview of AI advancements that have driven recent interest, offer a review of the current literature, and examine the most likely ways that AI will change radiology in the coming years.