U.S. Diagnostic Reference Levels and Achievable Doses for 10 Pediatric CT Examinations.

Background Diagnostic reference levels (DRLs) and achievable doses (ADs) were developed for the 10 most commonly performed pediatric CT examinations in the United States using the American College of Radiology Dose Index Registry. Purpose To develop robust, current, national DRLs and ADs for the 10 most commonly performed pediatric CT examinations as a function of patient age and size. Materials and Methods Data on 10 pediatric (ie, patients aged 18 years and younger) CT examinations performed between 2016 and 2020 at 1625 facilities were analyzed. For head and neck examinations, dose indexes were analyzed based on patient age; for body examinations, dose indexes were analyzed for patient age and effective diameter. Data from 1 543 535 examinations provided medians for AD and 75th percentiles for DRLs for volume CT dose index (CTDIvol), dose-length product (DLP), and size-specific dose estimate (SSDE). Results Of all facilities analyzed, 66% of the facilities (1068 of 1625) were community hospitals, 16% (264 of 1625) were freestanding centers, 9.5% (154 of 1625) were academic facilities, and 3.5% (57 of 1625) were dedicated children's hospitals. Fifty-two percent of the patients (798 577 of 1 543 535) were boys, and 48% (744 958 of 1 543 535) were girls. The median age of patients was 14 years (boys, 13 years; girls, 15 years). The head was the most frequent anatomy examined with CT (876 655 of 1 543 535 examinations [57%]). For head without contrast material CT examinations, the age-based CTDIvol AD ranged from 19 to 46 mGy, and DRL ranged from 23 to 55 mGy, with both AD and DRL increasing with age. For body examinations, DRLs and ADs for size-based CTDIvol, SSDE, and DLP increased consistently with the patient's effective diameter. Conclusion Diagnostic reference levels and achievable doses as a function of patient age and effective diameter were developed for the 10 most commonly performed CT pediatric examinations using American College of Radiology Dose Index Registry data. These benchmarks can guide CT facilities in adjusting pediatric CT protocols and resultant doses for their patients. © RSNA, 2021 An earlier incorrect version appeared online. This article was corrected on October 29, 2021.

U.S. PET/CT and Gamma Camera Diagnostic Reference Levels and Achievable Administered Activities for Noncardiac Nuclear Medicine Studies.

Existing surveys of radiopharmaceutical doses for U.S. nuclear medicine laboratories are of limited scope and size. Dose data are important because they can be used to benchmark individual laboratories, understand geographic variations in practice, and provide source data for societal guidelines and appropriateness criteria. Diagnostic reference levels (DRLs) and achievable administered activities (AAAs) for 13 noncardiac adult gamma camera and PET/CT examinations were derived retrospectively from American College of Radiology accreditation data (January 1, 2015, to December 31, 2017). The calculated DRL and AAA are consistent with previously published surveys. The distributions of radiopharmaceutical doses across facilities are in general consistent but show variation within a particular examination. Analysis of dose distribution suggests this variation results from differences in clinical protocols, educational gaps, and/or equipment factors. The AAA for the surveyed facilities exceeds dose ranges proposed in societal practice guidelines for several common nuclear medicine studies. Compared with similar surveys from Europe and Japan, geographic variation is observed, with some doses greater and others lower than used in the United States. Overall, radiopharmaceutical dose variation within the United States and internationally, and deviation from societal guidelines, imply that these dose-related benchmarks may be used to further standardize and improve clinical practice.

U.S. Diagnostic Reference Levels and Achievable Doses for 10 Adult CT Examinations.

Purpose To develop diagnostic reference levels (DRLs) and achievable doses (ADs) for the 10 most common adult computed tomographic (CT) examinations in the United States as a function of patient size by using the CT Dose Index Registry. Materials and Methods Data from the 10 most commonly performed adult CT head, neck, and body examinations from 583 facilities were analyzed. For head examinations, the lateral thickness was used as an indicator of patient size; for neck and body examinations, water-equivalent diameter was used. Data from 1 310 727 examinations (analyzed by using SAS 9.3) provided median values, as well as means and 25th and 75th (DRL) percentiles for volume CT dose index (CTDIvol), dose-length product (DLP), and size-specific dose estimate (SSDE). Applicable results were compared with DRLs from eight countries. Results More than 46% of the facilities were community hospitals; 13% were academic facilities. More than 48% were in metropolitan areas, 39% were suburban, and 13% were rural. More than 50% of the facilities performed fewer than 500 examinations per month. The abdomen and pelvis was the most frequently performed examination in the study (45%). For body examinations, DRLs (75th percentile) and ADs (median) for CTDIvol, SSDE, and DLP increased consistently with the patient's size (water-equivalent diameter). The relationships between patient size and DRLs and ADs were not as strong for head and neck examinations. These results agree well with the data from other countries. Conclusion DRLs and ADs as a function of patient size were developed for the 10 most common adult CT examinations performed in the United States. © RSNA, 2017.

Adult Gamma Camera Myocardial Perfusion Imaging: Diagnostic Reference Levels and Achievable Administered Activities Derived From ACR Accreditation Data.

PURPOSE: The aim of this study was to glean from accreditation surveys of US nuclear medicine facilities the in-practice radiopharmaceutical diagnostic reference levels (DRLs) and achievable administered activities (AAAs) for adult gamma camera myocardial perfusion imaging (MPI). METHODS: Data were collected from the ACR Nuclear Medicine Accreditation Program during one three-year accreditation cycle from May 1, 2012, to April 30, 2015. Data elements included radiopharmaceutical, administered activity, examination protocol, interpreting physician specialty, practice type, and facility annual examination volume. Facility demographics, DRLs, and AAAs were tabulated for analysis. RESULTS: The calculated DRLs and AAAs are consistent with previously published surveys, and they adhere to national societal guidelines. Facilities seeking ACR accreditation are nearly evenly split between hospital based with multiple gamma cameras and office based with single gamma cameras. The majority of facilities use single-day, low-dosage/high-dosage (99m)Tc-based protocols; a small minority use (201)TlCl protocols. Administered activities show a consistency across facilities, likely reflecting adoption of standard MPI protocols. CONCLUSIONS: This practice-based analysis provides DRL and AAA benchmarks that nuclear medicine facilities may use to refine gamma camera MPI protocols. In general, the protocols submitted for ACR accreditation are consistent with national societal guidelines. The results suggest that there may be opportunities to further reduce patient radiation exposure by using modified examination protocols and newer gamma camera software and hardware technologies.

Clinical implementation of the National Electrical Manufacturers Association CT Dose Check standard at ACR Dose Index Registry sites.

PURPOSE: The goal of the study was to determine if and how the National Electrical Manufacturers Association CT Dose Check standard has been implemented in clinical practice. METHODS: A survey was conducted of all sites participating in the ACR Dose Index Registry, using a web-based survey instrument, to determine whether respondents were aware of the CT Dose Check standard and the American Association of Physicists in Medicine (AAPM) recommendations for Dose Alert values, and if clinical sites had implemented it. RESULTS: A total of 170 responses were received, representing 37% (170/460) of surveys sent and 23% (170/734) of facilities participating in the ACR Dose Index Registry. Of responding facilities, 57.1% (96/168) were aware of the CT Dose Check standard, and 51.2% (86/168) were aware of the AAPM recommendations. At 44% (73/165) of responding facilities, at least 1 CT scanner with Dose Check capability was present. Of sites responding that they had at least 1 CT scanner with this capability, 57% (42/74) had implemented Dose Alerts, and 71% (30/42) had implemented Dose Notifications on CT scanners with the capability. Most responding sites were located in community hospitals (55.8%; 86/154). CONCLUSIONS: Although the National Electrical Manufacturers Association CT Dose Check standard and the AAPM recommendations for its use had been available for at least 2 years at the time of the survey, nearly half of the participating sites were not familiar with them. Education and outreach are needed if this tool is to be used effectively.

Curbing potential radiation-induced cancer risks in oncologic imaging: perspectives from the 'image gently' and 'image wisely' campaigns.

Medical imaging that uses ionizing radiation, such as CT, radiography, nuclear medicine, and fluoroscopy, is a cornerstone of the care of oncology patients and provides great benefit. Ionizing radiation at high doses is a known carcinogen.The exact degree of the risk of carcinogenesis from the lower doses of ionizing radiation used in medical imaging is less clear. The purpose of this review is to provide the oncology community with knowledge about the doses used in medical imaging, radiation-induced cancer risks from imaging, considerations to keep in mind when balancing imaging benefits and risks in pediatric and adult oncologic settings, dose reduction strategies, and the "Image Gently" and "Image Wisely" campaigns; the latter campaigns facilitate the translation of existing evidence into best practices for providers and patients.

Radiation protection and dose monitoring in medical imaging: a journey from awareness, through accountability, ability and action but where will we arrive?

Radiation awareness and protection of patients have been the fundamental responsibilities in diagnostic imaging since the discovery of x-rays late in 1895 and the first reports of radiation injury in 1896. In the ensuing years, there have been significant advancements in equipment that uses either x-rays to form images, such as fluoroscopy or computed tomography (CT), or the types of radiation emitted during nuclear imaging procedures (e.g., positron emission tomography [PET]). These advancements have allowed detailed and indispensable evaluation of a vast array of disorders. In fact, in 2001, CT and MRI were cited by physicians as the most significant medical innovations in the previous 3 decades. Rapid technological advancements in the last decade with CT, especially, have required imaging professionals to keep pace with increasingly complex technology to derive the maximum benefits of improved image acquisition and display techniques, in essence, the improved quality of the examination. It has also been challenging to fulfill the fundamental responsibilities of safety during this period of rapid growth (e.g., radiation protection, management of the risk of additional interventions driven by incidental findings, performing studies that were not indicated). The purpose of this paper is to define critical issues pertinent to ensuring patient safety through the appropriate assessment, recording, monitoring, and reporting of the radiation dose from CT.

The ACR/Society of Breast Imaging Resident and Fellowship Training Curriculum for Breast Imaging, updated.

The education committees of the ACR Commission on Breast Imaging and the Society of Breast Imaging have revised the resident and fellowship training curriculum to reflect the current state of breast imaging in the United States. The original curriculum, created by the Society of Breast Imaging in 2000, had been updated only once before, in 2006. Since that time, a number of significant changes have occurred in the way mammography is acquired, how adjunctive breast imaging methods are used, and how pathology is assessed. This curricular update is meant to reflect these and other changes and to offer guidance to educators and trainees in preparing those interested in providing breast imaging services.

Image Gently: progress and challenges in CT education and advocacy.

Significant progress has been made in radiation protection for children during the last 10 years. This includes increased awareness of the need for radiation protection for pediatric patients with international partnerships through the Alliance for Radiation Safety in Pediatric Imaging. This paper identifies five areas of significant progress in radiation safety for children: the growth of the Alliance; the development of an adult radiation protection campaign Image Wisely™; increased collaboration with government agencies, societies and the vendor community; the development of national guidelines in pediatric nuclear medicine, and the development of a size-based patient dose correction factor by the American Association of Physicists in Medicine, Task Group 204. However, many challenges remain. These include the need for continued education and change of practice at adult-focused hospitals where many pediatric CT exams are performed; the need for increased emphasis on appropriateness of pediatric imaging and outcomes research to validate the performance of CT studies, and the advancement of the work of the first pediatric national dose registry to determine the "state of the practice" with the final goal of establishing ranges of optimal CT technique for specific scan indications when imaging children with CT.

Approaches to promotion and implementation of action on Radiation Protection for children.

The Radiation Protection in Medicine conference, reviewed in this journal supplement, outlined nine strategies to promote radiation protection for patients. The Alliance for Radiation Safety in Pediatric Imaging has focused its work on three of those areas: creating awareness of the need and opportunities for radiation protection for children; developing open-source educational materials for medical professionals and parents on this critical topic for improved patient safety and communication; and lastly, advocating on behalf of children with industry, government and regulatory bodies to improve equipment design and safety features, standardisation of nomenclature and displays of dose reports across vendor platforms that reflect the special considerations of children.

ACR white paper on radiation dose in medicine: three years later.

The benefits of diagnostic imaging are immense and have revolutionized the practice of medicine. The increased sophistication and clinical efficacy of imaging have resulted in its dramatic growth over the past quarter century. However, the evolution of imaging has also resulted in a significant increase in the population's cumulative exposure to ionizing radiation and a potential increase in cancer risk. The ACR, an advocate for radiation safety since its inception in 1924, convened the ACR Blue Ribbon Panel on Radiation Dose in Medicine in 2006 and issued 37 recommendations for the College to address these issues. This report updates the status of these recommendations.

The ACR BI-RADS experience: learning from history.

The Breast Imaging Reporting and Data System (BI-RADS) initiative, instituted by the ACR, was begun in the late 1980s to address a lack of standardization and uniformity in mammography practice reporting. An important component of the BI-RADS initiative is the lexicon, a dictionary of descriptors of specific imaging features. The BI-RADS lexicon has always been data driven, using descriptors that previously had been shown in the literature to be predictive of benign and malignant disease. Once established, the BI-RADS lexicon provided new opportunities for quality assurance, communication, research, and improved patient care. The history of this lexicon illustrates a series of challenges and instructive successes that provide a valuable guide for other groups that aspire to develop similar lexicons in the future.

Image Gently Vendor Summit: working together for better estimates of pediatric radiation dose from CT.

OBJECTIVE: Medical physicists currently use two standardized phantoms to estimate CT patient radiation dose. This "one-size-fits-all" adult model results in underestimates of displayed pediatric CT radiation dose on the console of current CT scanners. The purpose of this article is to discuss the Alliance for Radiation Safety in Pediatric Imaging Vendor Summit. CONCLUSION: Stakeholders were invited to discuss the development of better estimates of pediatric patient radiation dose. These stakeholders agreed to partner to improve CT radiation dose estimates for children.

Image Gently(SM): a national education and communication campaign in radiology using the science of social marketing.

Communication campaigns are an accepted method for altering societal attitudes, increasing knowledge, and achieving social and behavioral change particularly within public health and the social sciences. The Image Gently(SM) campaign is a national education and awareness campaign in radiology designed to promote the need for and opportunities to decrease radiation to children when CT scans are indicated. In this article, the relatively new science of social marketing is reviewed and the theoretical basis for an effective communication campaign in radiology is discussed. Communication strategies are considered and the type of outcomes that should be measured are reviewed. This methodology has demonstrated that simple, straightforward safety messages on radiation protection targeted to medical professionals throughout the radiology community, utilizing multiple media, can affect awareness potentially leading to change in practice.

American College of Radiology white paper on radiation dose in medicine.

The benefits of diagnostic imaging are immense and have revolutionized the practice of medicine. The increased sophistication and clinical efficacy of imaging have resulted in its dramatic growth over the past quarter century. Although data derived from the atomic bomb survivors in Japan and other events suggest that the expanding use of imaging modalities using ionizing radiation may eventually result in an increased incidence of cancer in the exposed population, this problem can likely be minimized by preventing the inappropriate use of such imaging and by optimizing studies that are performed to obtain the best image quality with the lowest radiation dose. The ACR, which has been an advocate for radiation safety since its inception in 1924, convened the ACR Blue Ribbon Panel on Radiation Dose in Medicine to address these issues. This white paper details a proposed action plan for the college derived from the deliberations of that panel.