Benefits and limitations for the use of radiation dose management systems in medical imaging. practical experience in a university hospital

Objectives: Radiation dose management systems (DMS) are currently to help improve radiation protection in medical imaging and interventions. This study presents our experience using a homemade DMS called DOLQA (Dose On-Line for Quality Assurance). Methods: Our DMS is connected to 14 X-ray systems in a university hospital linked to the central data repository of a large network of 16 public hospitals in the Autonomous Community of Madrid, with 6.7 million inhabitants. The system allows us to manage individual patient dose data and groups of procedures with the same clinical indications, and compare them with diagnostic reference levels (DRLs). The system can also help to prioritize optimisation actions. Results: This study includes results of imaging examinations from 2020, with 3,7601 procedures and 28,6471 radiation events included in the radiation dose structured reports (RDSR), for computed tomography (CT), interventional procedures, positron emission tomography-CT (PET-CT) and mammography. Conclusions: The benefits of the system include: automatic registration and management of patient doses, creation of dose reports for patients, information on recurrent examinations, high dose alerts, and help to define optimisation actions. The system requires the support of medical physicists and implication of radiologists and radiographers. DMSs must undergo periodic quality controls and audit reports must be drawn up and submitted to the hospital’s quality committee. The drawbacks of DMSs include the need for continuous external support (medical physics experts, radiologists, radiographers, technical services of imaging equipment and hospital informatics services) and the need to include data on clinical indication for the imaging procedures. Advances in knowledge: DMS perform automatic management of radiation doses, produces patient dose reports, and registers high dose alerts to suggest optimisation actions. Benefits and limitations are derived from the practical experience in a large university hospital.

Acquisition of a Dose Management System with Consideration of Medico-Legal and Economic Aspects

Background New radiation protection regulation encompassing additional obligations for monitoring, reporting and recording of radiation exposure, was enacted on December 31, 2018. As a consequence, dose management systems (DMS) are necessary to fulfill the requirements. The process of selection, acquisition and implementation of a suitable IT solution for this purpose is a challenge that all X-ray-applying facilities, including hospitals and private practices, are currently facing. Method A target/actual-analysis as well as a cost-utility analysis is presented for this specific case as a foundation for the acquisition decision-making process. Result An actual analysis is necessary in order to record the current status of dose documentation. An interdivisional approach is recommended to include all imaging modalities and devices. An interdisciplinary steering committee can be helpful in enabling consensus and rapid action. A target analysis includes additional criteria with respect to ease of operation, technical feasibility, process optimization and research opportunities to consider in addition to the statutory requirements. By means of a cost-benefit analysis, considerations between costs and the individually weighted advantages and disadvantages of eligible DMS result in a ranking of preference for the available solutions. Conclusion Requirements of a DMS can be summarized in a specification sheet. Deploying an actual condition analysis, target state analysis and cost-utility analysis can help to identify a suitable DMS to achieve rapid commissioning and highest possible user acceptance while optimizing costs at the same time. Key Points: Citation Format

Radiation nephropathy: Dose, management, and population risk

Radiation nephropathy is renal injury caused by a sufficient dose of irradiation. It can result from external beam irradiation or internal irradiation as might occur from therapeutic radioisotopes. Its usual clinical presentation is as chronic kidney disease occurring some months after irradiation, and it can evolve to end-stage-renal-disease. While the immediate cellular injury from irradiation depends on radiolysis of water and oxidative DNA damage, there is no conclusive evidence for chronic persistent oxidative stress or inflammation as the cause of the multi-tissue scarring that ensues. Antagonists of the renin-angiotensin system are effective treatments for experimental radiation nephropathy but their preferential value in human clinical medicine is unproven.

P.026 Erenumab associated with high persistence among Canadian patients for preventive treatment of chronic and episodic migraine in real-world practice

Background: Real world use of oral prophylactic migraine therapies is often limited by poor patient tolerance. The objective of this study was to describe the demographics and clinical characteristics of patients prescribed erenumab following its launch in Canada (September 2018) and to evaluate the real-world treatment persistence and dose management. Methods: This was a retrospective, descriptive analysis of de-identified secondary patient data that includes baseline demographics, clinical characteristics, plus erenumab treatment management, collected through Novartis’ Go Program® (Patient Support Program). Only data collected from patients with a documented informed consent were included in the analysis. Results: 14,282 patients met eligibility criteria. The mean age of patients was 46.3 years, 83.0% were female, and 66.1% reported having ≥15 monthly migraine days. 52.5% were initiated on the 140 mg dose of erenumab and 59.3% of those who initiated the 70 mg dose escalated to 140 mg within 360 days. After 360 and 450 days, the KM-derived persistence was 71.0% and 63.4%, respectively. Conclusions: The high persistence reported here suggests that erenumab has a meaningful degree of tolerability in the real-world setting and increases confidence that the real-world use and benefits of erenumab will not be undermined by the poor persistence observed with traditional migraine prophylactic agents.

A deep-learning method using computed tomography scout images for estimating patient body weight

Body weight is an indispensable parameter for determination of contrast medium dose, appropriate drug dosing, or management of radiation dose. However, we cannot always determine the accurate patient body weight at the time of computed tomography (CT) scanning, especially in emergency care. Time-efficient methods to estimate body weight with high accuracy before diagnostic CT scans currently do not exist. In this study, on the basis of 1831 chest and 519 abdominal CT scout images with the corresponding body weights, we developed and evaluated deep-learning models capable of automatically predicting body weight from CT scout images. In the model performance assessment, there were strong correlations between the actual and predicted body weights in both chest (ρ = 0.947, p < 0.001) and abdominal datasets (ρ = 0.869, p < 0.001). The mean absolute errors were 2.75 kg and 4.77 kg for the chest and abdominal datasets, respectively. Our proposed method with deep learning is useful for estimating body weights from CT scout images with clinically acceptable accuracy and potentially could be useful for determining the contrast medium dose and CT dose management in adult patients with unknown body weight.

The U.S. food and drug administration’s role in improving radiation dose management for medical x-ray imaging devices

The U.S. Food and Drug Administration (FDA) has been concerned with minimizing the unnecessary radiation exposure of people for half a century. Manufacturers of medical X-ray imaging devices are important partners in this effort. Medical X-ray imaging devices are regulated under both FDA’s electronic product regulations and FDA’s medical device regulations. FDA also publishes guidance documents that represent FDA’s current thinking on a topic and provide a suggested or recommended approach to meet the requirements of a regulation or statute. FDA encourages manufacturers to develop medical devices that conform to voluntary consensus standards. Use of these standards is a central element of FDA’s system to ensure that all medical devices marketed in the U.S. meet safety and effectiveness requirements. FDA staff participate actively in the development and maintenance of these standards, often advancing or introducing new safety and dose management requirements. Use of voluntary consensus standards reduces the amount of time necessary to evaluate a premarket submission and reduces the burden on manufacturers. FDA interacts with industry and other stakeholders through meetings with industry groups, public meetings, public communications, and through the development of voluntary consensus standards. In these interactions, FDA staff introduce new concepts for improving the safety of these devices and provide support for similar initiatives from professional organizations. FDA works with all stakeholders to achieve its mission of protecting and promoting the public health.

Cumulative effective dose from recurrent CT examinations in Europe: proposal for clinical guidance based on an ESR EuroSafe Imaging survey

In recent years, the issue of cumulative effective dose received from recurrent computed tomography examinations has become a subject of increasing concern internationally. Evidence, predominantly from the USA, has shown that a significant number of patients receive a cumulative effective dose of 100 mSv or greater. To obtain a European perspective, EuroSafe Imaging carried out a survey to collect European data on cumulative radiation exposure of patients from recurrent computed tomography examinations. The survey found that a relatively low percentage of patients (0.5%) received a cumulative effective dose equal to or higher than 100 mSv from computed tomography, most of them having an oncological disease. However, there is considerable variation between institutions as these values ranged from 0 to 2.72%, highlighting that local practice or, depending on the institution and its medical focus, local patient conditions are likely to be a significant factor in the levels of cumulative effective dose received, rather than this simply being a global phenomenon. This paper also provides some practical actions to support the management of cumulative effective dose and to refine or improve practice where recurrent examinations are required. These actions are focused around increasing awareness of referring physicians through encouraging local dialogue, actions focused on optimisation where a team approach is critical, better use of modern equipment and the use of Dose Management and Clinical Decision Support Systems together with focused clinical audits. The proper use of cumulative effective dose should be part of training programmes for referrers and practitioners, including what information to give to patients. Patient summary Radiation is used to the benefit of patients in diagnostic procedures such as CT examinations, and in therapeutic procedures like the external radiation treatment for cancer. However, radiation is also known to increase the risk of cancer. To oversee this risk, the cumulative effective dose (CED) received by a patient from imaging procedures over his or her life is important. In this paper, the authors, on behalf of EuroSafe Imaging, report on a survey carried out in Europe that aims to estimate the proportion of patients that undergo CT examinations and are exposed to a CED of more than 100 mSv. At the same time, the survey enquires about and underlines radiologists’ measures and radiology departments’ strategies to limit such exposure. Over the period of 2015–2018, respondents reported that 0.5% (0–2.72%) of patients were exposed to a CED of ≥ 100 mSv from imaging procedures. The background radiation dose in Europe depends on the location, but it is around 2.5 mSv per year. It is obvious that patients with cancer, chronic diseases and trauma run the highest risk of having a high CED. However, even if the number of patients exposed to ≥ 100 mSv is relatively low, it is important to lower this number even further. Measures could consist in using procedures that do not necessitate radiation, using very low dose procedures, being very critical in requiring imaging procedures and increasing awareness about the issue. Key Points • A relatively low percentage of patients (0.5%) received a cumulative effective dose from CT computed tomography equal to or greater than 100 mSv, in Europe, most of them having an oncological disease. • There is a wide range in the number of patients who receive cumulative effective dose equal to or greater than 100 mSv (0–2.72%) and optimisation should be improved. • Increasing the awareness of referring physicians through encouraging local dialogue, concrete actions focused on optimisation and development of dose management systems is suggested.

How to Measure/Calculate Radiation Dose in Patients?

Patients in fluoroscopically guided interventions (FGI) may be exposed to substantial radiation dose levels (SRDL). The most commonly reported adverse reactions are skin injuries with erythema or necrosis. It is therefore important for the interventional radiologist to know deterministic effects with their threshold doses. If possible all relevant modality parameters should be displayed on the interventionalists screen. Dosimetric parameters should be displayed in digital imaging and communications in medicine (DICOM) units and stored as DICOM Radiation Dose Structured Report (RDSR). The peak skin dose (PSD) is the most relevant risk parameter for skin injuries. Dose management systems (DMS) help optimising radiation exposure of patients. However, their calculation of skin dose maps is only available after a FGI. Therefore, dose maps and PSD should preferably be calculated and displayed in real time by the modality.