The ICRP, MELODI, and ALLIANCE workshop on effects of ionizing radiation exposure in offspring and next generations: a summary of discussions

PURPOSE

Task Group 121 - Effects of ionizing radiation exposure in offspring and next generations - is a task group under the Committee 1 of the International Commission on Radiological Protection (ICRP), approved by the Main Commission on 18th November 2021. The main goals of Task Group 121 are to (1) review and update the scientific literature of relevance to radiation-related effects in the offspring of parent(s) exposed to ionizing radiation in both human and non-human biota; (2) to assess preconceptional and intrauterine effects of radiation exposure and related morbidity and mortality; and, (3) to provide advice about the level of evidence and how to consider these preconceptional and postconceptional effects in the system of radiological protection for humans and non-human biota.

METHODS

The Task Group is reviewing relevant literature since Publication 90 'Biological effects after prenatal irradiation (embryo and fetus)' (2003) and will include radiation-related effects on future generations in humans, animals, and plants. This review will be conducted to account for the health effects on offspring and subsequent generations in the current system of radiological protection. Radiation detriment calculation will also be reviewed. Finally, preliminary recommendations will be made to update the integration of health effects in offspring and next generations in the system of radiological protection.

RESULTS

A Workshop, jointly organized by ICRP Task Group 121 and European Radiation Protection Research Platforms MELODI and ALLIANCE was held in Budapest, Hungary, from 31st May to 2nd June 2022. Participants discussed four important topics: (1) hereditary and epigenetic effects due to exposure of the germ cell line (preconceptional exposure), (2) effects arising from exposure of the embryo and fetus (intrauterine exposure), (3) transgenerational effects on biota, and (4) its potential impact on the system of radiological protection.

CONCLUSIONS

Based on the discussions and presentations during the breakout sessions, newer publications, and gaps on the current scientific literature were identified. For instance, there are some ongoing systematic reviews and radiation epidemiology reviews of intrauterine effects. There are newer methods of Monte Carlo simulation for fetal dosimetry, and advances in radiation genetics, epigenetics, and radiobiology studies. While the current impact of hereditary effects on the global detriment was reported as small, the questions surrounding the effects of radiation exposure on offspring and the next generation are crucial, recurring, and with a major focus on exposed populations. This article summarizes the workshop discussions, presentations, and conclusions of each topic and introduces the special issue of the International Journal of Radiation Biology resulting from the discussions of the meeting.

Radiological protection in human research ethics using a case study: toward update of the ICRP Publication 62

The benefits of biomedical research involving humans are well recognised, along with the need for conformity to international standards of science and ethics. When human research involves radiation imaging procedures or radiotherapy, an extra level of expert review should be provided from the point of view of radiological protection. The relevant publication of the International Commission for Radiological Protection (ICRP) is now three decades old and is currently undergoing an update. This paper aims to provoke discussions on how the risks of radiation dose and the benefits of research should be assessed, using a case study of diagnostic radiology involving volunteers for whom there is no direct benefit. Further, the paper provides the current understanding of key concepts being considered for review and revision-such as the dose constraint and the novel research methods on the horizon, including radiation biology and epidemiology. The analysis revisits the perspectives described in the ICRP Publication 62, and considers the recent progress in both radiological protection ethics and medical research ethics.

A Multimedia Strategy to Integrate Introductory Broad-Based Radiation Science Education in US Medical Schools

US physicians in multiple specialties who order or conduct radiological procedures lack formal radiation science education and thus sometimes order procedures of limited benefit or fail to order what is necessary. To this end, a multidisciplinary expert group proposed an introductory broad-based radiation science educational program for US medical schools. Suggested preclinical elements of the curriculum include foundational education on ionizing and nonionizing radiation (eg, definitions, dose metrics, and risk measures) and short- and long-term radiation-related health effects as well as introduction to radiology, radiation therapy, and radiation protection concepts. Recommended clinical elements of the curriculum would impart knowledge and practical experience in radiology, fluoroscopically guided procedures, nuclear medicine, radiation oncology, and identification of patient subgroups requiring special considerations when selecting specific ionizing or nonionizing diagnostic or therapeutic radiation procedures. Critical components of the clinical program would also include educational material and direct experience with patient-centered communication on benefits of, risks of, and shared decision making about ionizing and nonionizing radiation procedures and on health effects and safety requirements for environmental and occupational exposure to ionizing and nonionizing radiation. Overarching is the introduction to evidence-based guidelines for procedures that maximize clinical benefit while limiting unnecessary risk. The content would be further developed, directed, and integrated within the curriculum by local faculties and would address multiple standard elements of the Liaison Committee on Medical Education and Core Entrustable Professional Activities for Entering Residency of the Association of American Medical Colleges.

Age effects on radiation response: summary of a recent symposium and future perspectives

One of the principal uncertainties when estimating population risk of late effects from epidemiological data is that few radiation-exposed cohorts have been followed up to extinction. Therefore, the relative risk model has often been used to estimate radiation-associated risk and to extrapolate risk to the end of life. Epidemiological studies provide evidence that children are generally at higher risk of cancer induction than adults for a given radiation dose. However, the strength of evidence varies by cancer site and questions remain about site-specific age at exposure patterns. For solid cancers, there is a large body of evidence that excess relative risk (ERR) diminishes with increasing age at exposure. This pattern of risk is observed in the Life Span Study (LSS) as well as in other radiation-exposed populations for overall solid cancer incidence and mortality and for most site-specific solid cancers. However, there are some disparities by endpoint in the degree of variation of ERR with exposure age, with some sites (e.g., colon, lung) in the LSS incidence data showing no variation, or even increasing ERR with increasing age at exposure. The pattern of variation of excess absolute risk (EAR) with age at exposure is often similar, with EAR for solid cancers or solid cancer mortality decreasing with increasing age at exposure in the LSS. We shall review the human data from the Japanese LSS cohort, and a variety of other epidemiological data sets, including a review of types of medical diagnostic exposures, also some radiobiological animal data, all bearing on the issue of variations of radiation late-effects risk with age at exposure and with attained age. The paper includes a summary of several oral presentations given in a Symposium on "Age effects on radiation response" as part of the 67th Annual Meeting of the Radiation Research Society, held virtually on 3-6 October 2021.

Radiation exposures in pregnancy, health effects and risks to the embryo/foetus-information to inform the medical management of the pregnant patient

Generally, intentional exposure of pregnant women is avoided as far as possible in both medical and occupational situations. This paper aims to summarise available information on sources of radiation exposure of the embryo/foetus primarily in medical settings. Accidental and unintended exposure is also considered. Knowledge on the effects of radiation exposure on the developing embryo/foetus remains incomplete-drawn largely from animal studies and two human cohorts but a summary is provided in relation to the key health endpoints of concern, severe foetal malformations/death, future cancer risk, and future impact on cognitive function. Both the specific education and training and also the literature regarding medical management of pregnant females is in general sparse, and consequently the justification and optimisation approaches may need to be considered on a case by case basis. In collating and reviewing this information, several suggestions for future basic science research, education and training, and radiation protection practice are identified.

Radiological protection of the patient in veterinary medicine and the role of ICRP

At the request of the Main Commission of the International Commission on Radiological Protection (ICRP), Task Group 107 (TG107) was set up to consider the issue of radiological protection of the patient in veterinary medicine. TG107, who authored this article, brought together information relating to the use of diagnostic imaging and radiation oncology in veterinary medicine. A number of specific areas were identified that appeared to be appropriate for attention by ICRP. These included the use of dose quantities and units, the need for re-evaluation of stochastic and deterministic risks from ionising radiation in animals, and the growing use of imaging and therapeutic equipment for animals that is little different from that available to humans. TG107 unanimously recommended that it was both appropriate and timely for ICRP to consider and advise on these issues, and the Main Commission agreed. This paper summarises the findings of TG107.

Individual response of humans to ionising radiation: governing factors and importance for radiological protection

Tissue reactions and stochastic effects after exposure to ionising radiation are variable between individuals but the factors and mechanisms governing individual responses are not well understood. Individual responses can be measured at different levels of biological organization and using different endpoints following varying doses of radiation, including: cancers, non-cancer diseases and mortality in the whole organism; normal tissue reactions after exposures; and, cellular endpoints such as chromosomal damage and molecular alterations. There is no doubt that many factors influence the responses of people to radiation to different degrees. In addition to the obvious general factors of radiation quality, dose, dose rate and the tissue (sub)volume irradiated, recognized and potential determining factors include age, sex, life style (e.g., smoking, diet, possibly body mass index), environmental factors, genetics and epigenetics, stochastic distribution of cellular events, and systemic comorbidities such as diabetes or viral infections. Genetic factors are commonly thought to be a substantial contributor to individual response to radiation. Apart from a small number of rare monogenic diseases such as ataxia telangiectasia, the inheritance of an abnormally responsive phenotype among a population of healthy individuals does not follow a classical Mendelian inheritance pattern. Rather it is considered to be a multi-factorial, complex trait.

Multiphase acquisitions in pediatric abdominal-pelvic CT are a common practice and contribute to unnecessary radiation dose

BACKGROUND

Many patients at our pediatric hospital have had a contrast-enhanced CT of the abdomen and pelvis performed by an outside imaging facility before admission. We have noticed that many of these exams are multiphase, which may contribute to unnecessary radiation dose.

OBJECTIVE

To determine the frequency of multiphase acquisitions and radiation dose indices in contrast-enhanced CTs of the abdomen and pelvis performed by outside imaging facilities in patients who were subsequently transferred to our pediatric hospital for care, and compare these metrics to contrast-enhanced CTs of the abdomen and pelvis performed internally.

MATERIALS AND METHODS

A retrospective analysis was performed of contrast-enhanced CTs of the abdomen and pelvis from outside imaging facilities uploaded to our picture archiving and communication system (PACS) between January 1, 2012, and December 31, 2015. CT images and dose pages were reviewed to determine the number of phases and dose indices (CT dose index-volume [CTDI_vol], dose-length product, size-specific dose estimate). Exams for abdominal or pelvic mass, trauma or urinary leak indications were excluded. Data were compared to internally acquired contrast-enhanced CTs of the abdomen and pelvis by querying the American College of Radiology (ACR) Dose Index Registry. This review was institutional review board and HIPAA compliant.

RESULTS

There were 754 contrast-enhanced CTs of the abdomen and pelvis from 104 outside imaging facilities. Fifty-three percent (399/754) had 2 phases, and 2% (14/754) had 3 or more phases. Of the 939 contrast-enhanced CTs of the abdomen and pelvis performed internally, 12% (115) were multiphase exams. Of 88% (664) contrast-enhanced CTs of the abdomen and pelvis from outside imaging facilities with dose data, CTDI_vol was 2.7 times higher than our institution contrast-enhanced CTs of the abdomen and pelvis (939) for all age categories as defined by the ACR Dose Index Registry (mean: 9.4 vs. 3.5 mGy, P<0.0001). The majority (74%) of multiphase exams were performed by 9 of 104 outside imaging facilities.

CONCLUSION

Multiphase acquisitions in routine contrast-enhanced CT of the abdomen and pelvis exams at outside imaging facilities are more frequent than those at a dedicated pediatric institution and contribute to unnecessary radiation dose. A contrast-enhanced CT of the abdomen and pelvis exam from an outside imaging facility with two passes may have as much as four times to six times the dose as the same exam performed with a single pass at a pediatric imaging center. We advocate for imaging facilities with high multiphase rates to eliminate multiple phases from routine contrast-enhanced CT of the abdomen and pelvis exams in children.

Noncontrast Head CT in Children: National Variation in Radiation Dose Indices in the United States

BACKGROUND AND PURPOSE

Radiologists should manage the radiation dose for pediatric patients to maintain reasonable diagnostic confidence. We assessed the variation in estimated radiation dose indices for pediatric noncontrast head CT in the United States.

MATERIALS AND METHODS

Radiation dose indices for single-phase noncontrast head CT examinations in patients 18 years of age and younger were retrospectively reviewed between July 2011 and June 2016 using the American College of Radiology CT Dose Index Registry. We used the reported volume CT dose index stratified by patient demographics and imaging facility characteristics.

RESULTS

The registry included 295,296 single-phase pediatric noncontrast head CT studies from 1571 facilities (56% in male patients and 53% in children older than 10 years of age). The median volume CT dose index was 33 mGy (interquartile range = 22-47 mGy). The volume CT dose index increased as age increased. The volume CT dose index was lower in children's hospitals (median, 26 mGy) versus academic hospitals (median, 32 mGy) and community hospitals (median, 40 mGy). There was a lower volume CT dose index in level I and II trauma centers (median, 27 and 32 mGy, respectively) versus nontrauma centers (median, 40 mGy) and facilities in metropolitan locations (median, 30 mGy) versus those in suburban and rural locations (median, 41 mGy).

CONCLUSIONS

Considerable variation in the radiation dose index for pediatric head CT exists. Median dose indices and practice variations at pediatric facilities were both lower compared with other practice settings. Decreasing dose variability through proper management of CT parameters in pediatric populations using benchmarks generated by data from registries can potentially decrease population exposure to ionizing radiation.

Downstream Breast Imaging Following Screening Mammography in Medicare Patients with Advanced Cancer: A Population-Based Study

BACKGROUND

Screening tests are generally not recommended in patients with advanced cancer and limited life expectancy. Nonetheless, screening mammography still occurs and may lead to follow-up testing.

OBJECTIVE

We assessed the frequency of downstream breast imaging following screening mammography in patients with advanced colorectal or lung cancer.

DESIGN

Population-based study.

PARTICIPANTS

The study included continuously enrolled female fee-for-service Medicare beneficiaries ≥65 years of age with advanced colorectal (stage IV) or lung (stage IIIB-IV) cancer reported to a Surveillance, Epidemiology, and End Results (SEER) registry between 2000 and 2011.

MAIN MEASURES

We assessed the utilization of diagnostic mammography, breast ultrasound, and breast MRI following screening mammography. Logistic regression models were used to explore independent predictors of utilization of downstream tests while controlling for cancer type and patient sociodemographic and regional characteristics.

KEY RESULTS

Among 34,127 women with advanced cancer (23% colorectal; 77% lung cancer; mean age at diagnosis 75 years), 9% (n = 3159) underwent a total of 5750 screening mammograms. Of these, 11% (n = 639) resulted in at least one subsequent diagnostic breast imaging examination within 9 months. Diagnostic mammography was most common (9%; n = 532), followed by ultrasound (6%; n = 334) and MRI (0.2%; n = 14). Diagnostic mammography rates were higher in whites than African Americans (OR, 1.6; p <0.05). Higher ultrasound utilization was associated with more favorable economic status (OR, 1.8; p <0.05).

CONCLUSIONS

Among women with advanced colorectal and lung cancer, 9% continued screening mammography, and 11% of these screening studies led to at least one additional downstream test, resulting in costs with little likelihood of meaningful benefit.

Cancer-directed therapy and potential impact on survivals in nonresected hepatocellular carcinoma: SEER-Medicare population study

Aim: To investigate determinants of receiving cancer-directed therapies and their potential survival impact in nonresected hepatocellular carcinoma (HCC) Materials & methods: Nonsurgically resected HCC patients between 2000 and 2010 were stratified by American Joint Committee on Cancer staging and the type of therapy. Predictors of receiving therapy were identified and implication on survival was evaluated. Results: Out of 9239 patients included, those receiving any therapy demonstrated prolonged overall survival with following median overall survival (months): ablation (30.8), Yttrium-90 (15.6), transcatheter arterial chemoembolization (15.5), Sorafenib (5.6), versus no cancer-directed therapy (3.7; p-values <0.001). Overall, 36% of patients received cancer-directed therapy including 47% with stage I/II. Favorable sociodemographic factors predicted receipt of percutaneous locoregional therapies (p-values <0.05). Discussion & Conclusion: There appears to be significant disparity in care of nonresected HCC patients with significant underutilization of cancer-directed therapies.

Assessment of Added Value of Noncontrast to Contrast-Enhanced Abdominal Computed Tomography Scan for Characterization of Hypervascular Liver Metastases

Assess the added value of nonenhanced computed tomography (NECT) to contrast-enhanced CT (CECT) of the abdomen for characterization of hypervascular liver metastases and incidental findings. Institutional review board approved, Health Insurance Probability and Accountability Act compliant, retrospective study of patients with melanoma, neuroendocrine tumor, or thyroid cancer. First available triphasic abdomen CT after initial diagnosis was reviewed by 3 radiologists. The 3 most suspicious lesions were characterized on the CECT as benign or malignant and then recharacterized after reviewing the NECT with CECT. Incidental renal and adrenal lesions were characterized similarly. Diagnostic performance of CECT vs its combination with NECT was assessed. Statistical significance level was set at P < 0.05. A total of 81 patients were included (mean age = 55 years; 52% male; 64% with liver lesions; 27% and 11% with incidental renal and adrenal lesions, respectively). Percentage area under the curve and 95% CI of CECT vs combination with NECT for characterization of liver metastases was 98(94-100) vs 99(96-100) for reviewer 1 (P = 0.35), 93(86-100) vs 94(87-100) for reviewer 2 (P = 0.23), and 96(90-100) vs 99(97-100) for reviewer 3 (P = 0.32). Mean difference in area under the curve and 95% CI between 2 protocols for characterization of liver, renal, and adrenal lesions were -0.007(-0.05 to 0.04) (P = 0.63), -0.09(-0.25 to 0.07) (P = 0.22), and -0.01(-0.05 to 0.02) (P = 0.27), respectively. After addition of NECT, confidence level for lesion characterization increased 4%-15% for liver metastases, 18%-59% and 33%-67% for renal and adrenal lesions, respectively. In conclusion, while addition of NECT to CECT improved radiologist' confidence, there was no statistically significant change in characterization of hypervascular liver metastases or incidental renal and adrenal lesions.

Internet-based ICRP resource for healthcare providers on the risks and benefits of medical imaging that uses ionising radiation

The purpose of the International Commission on Radiological Protection (ICRP) Committee 3 Working Party was to update the 2001 web-based module 'Radiation and your patient: a guide for medical practitioners' from ICRP. The key elements of this task were: to clearly identify the target audience (such as healthcare providers with an emphasis on primary care); to review other reputable sources of information; and to succinctly publish the contribution made by ICRP to the various topics. A 'question-and-answer' format addressing practical topics was adopted. These topics included benefits and risks of imaging using ionising radiation in common medical situations, as well as pertaining to specific populations such as pregnant, breast-feeding, and paediatric patients. In general, the benefits of medical imaging and related procedures far outweigh the potential risks associated with ionising radiation exposure. However, it is still important to ensure that the examinations are clinically justified, that the procedure is optimised to deliver the lowest dose commensurate with the medical purpose, and that consideration is given to diagnostic reference levels for particular classes of examinations.

Stakeholders' Perceptions Regarding the Use of Patient Photographs Integrated with Medical Imaging Studies

Integrating digital facial photographs of pediatric patients as identifiers (ID) with medical imaging (integrated photographic IDs) may increase the detection of mislabeled studies. The purpose of this study was to determine how different stakeholders would receive this novel technology. Parents or guardians of patients in a children's hospital outpatient radiology department, radiology faculty and residents, and radiology technologists and nurses were asked to complete a survey. The perception about the anticipated use of integrated photographic ID in different clinical scenarios was investigated, and its predictors were determined using logistic regression analysis. Four hundred ninety-eight parents responded (response rate 83 %); 96 and 97 % supported the use of integrated photographic ID, if it improves the radiologist's imaging interpretation or decreases the rate of mislabeled errors, respectively. Thirty-eight percent were worried that photographic IDs would impact patients' privacy. Ninety-four percent believed that they should be asked for their consent prior to obtaining their child's photograph. Seventy-eight radiologists responded (response rate 39 %); 63 and 59 % believed that the use of integrated photographic ID would result in improvement in accurate interpretation of images and identification of mislabeled patient errors, respectively. Forty-nine percent of radiologists had concern that integrated photographic ID would increase interpretation time. Fifty technologists and nurses responded (response rate 59 %); 71 and 73 % supported the technology if it resulted in more acute interpretation of images and identification of mislabeled patients, respectively. A majority of stakeholders support integrated photographic ID in order to improve safety. A majority of parents believe that consent should be obtained.

Enteric Distribution of Oral Contrast in Emergency Department Patients Undergoing Abdominal-Pelvic Computed Tomography

PURPOSE

The study sought to assess the gastrointestinal (GI) distribution of oral contrast (OC) among emergency department (ED) patients and determine if contrast reaches the terminal ileum or site of pathology to assist in diagnosis.

METHODS

Retrospectively, adults undergoing abdominal-pelvic computed tomography (APCT) in the ED at 2 hospitals were identified over a 3-month period. APCTs were reviewed for location of OC. Presence, site, type of bowel pathology, and prior gastrointestinal surgery were documented. When applicable, the site of bowel pathology was evaluated for the presence or absence of OC.

RESULTS

There were 1349 exams with mean age 50.5 years (range 18-97 years), 41% male, with 530 (39%) receiving OC. In 271 of 530 (51%), OC reached the terminal ileum (TI). Bowel pathology was present in 31% of cases (165 of 530). When bowel pathology was present, 47% (77 of 165) had OC present at the pathology site. The GI tract was divided into 4 anatomic segments: OC most frequently reached pathology in stomach and duodenum (84%), but was present less frequently at sites of pathology from jejunum to TI (35%), proximal colon (57%), and distal colon (28%). In only 84 of 530 OC cases (16%) did contrast extend from the stomach to distal colon. OC administration contributed to longer mean APCT order to final report of 0.5 hours and longer mean ED length of stay of 0.8 hours compared with all patients who received APCT.

CONCLUSIONS

Optimal OC distribution is not achieved in more than half of ED patients, raising questions about the continued use of OC in the ED.

Sociodemographic impact on survival in unresectable hepatocellular carcinoma: a survival epidemiology and end results study

AIM

To investigate outcomes in unresectable hepatocellular carcinoma (HCC) patients stratified by sociodemographic and clinical factors in a population study.

MATERIALS & METHODS

Surveillance, Epidemiology and End Results (SEER) database was used to identify patients diagnosed in 2000-2011. Overall survival (OS) was stratified using patient sociodemographic characteristics and American Joint Commission on Cancer (AJCC) staging. Log-rank test and Cox proportional hazard models were used to identify prognostic factors of OS.

RESULTS

In patients with AJCC stage I and II unresectable HCC, prolonged OS was correlated with being married, younger age, ethnicity, geographic location, living in large urban areas, being insured and higher income and education levels.

CONCLUSION

In AJCC stage I and II unresectable HCC patients with favorable sociodemographic factors, prolonged OS maybe in part related to better access to cancer-directed therapy.

Optimizing Patient-centered Communication and Multidisciplinary Care Coordination in Emergency Diagnostic Imaging: A Research Agenda

Patient-centered emergency diagnostic imaging relies on efficient communication and multispecialty care coordination to ensure optimal imaging utilization. The construct of the emergency diagnostic imaging care coordination cycle with three main phases (pretest, test, and posttest) provides a useful framework to evaluate care coordination in patient-centered emergency diagnostic imaging. This article summarizes findings reached during the patient-centered outcomes session of the 2015 Academic Emergency Medicine consensus conference "Diagnostic Imaging in the Emergency Department: A Research Agenda to Optimize Utilization." The primary objective was to develop a research agenda focused on 1) defining component parts of the emergency diagnostic imaging care coordination process, 2) identifying gaps in communication that affect emergency diagnostic imaging, and 3) defining optimal methods of communication and multidisciplinary care coordination that ensure patient-centered emergency diagnostic imaging. Prioritized research questions provided the framework to define a research agenda for multidisciplinary care coordination in emergency diagnostic imaging.

Variation in Pediatric Cervical Spine Computed Tomography Radiation Dose Index

OBJECTIVES

The objective was to evaluate variation in the current estimated radiation dose index for pediatric cervical spine (c-spine) computed tomography (CT) examinations.

METHODS

This was a retrospective analysis of pediatric (age younger than 19 years) c-spine CT examinations from the American College of Radiology Dose Index Registry, July 2011 through December 2014. We used the volume CT dose index (CTDIvol) as the radiation dose estimate and used summary statistics to describe patient and hospital characteristics.

RESULTS

There were 12,218 pediatric CT c-spine examinations performed across 296 participating hospitals. Fifty-six percent were in male patients, and 79% were in children older than 10 years. Most hospitals (55%) were community hospitals without trauma designations, and the largest proportion of examinations (41%) were performed at these hospitals. The median CTDIvol was 15 mGy (interquartile range = 9 to 23 mGy) representing a more than 2.5-fold difference between the 25th and 75th percentiles. Pediatric hospitals (both trauma and nontrauma centers) delivered the lowest CTDIvol across all age groups and showed the least amount of variability in dose.

CONCLUSIONS

There is significant variation in the radiation dose index for pediatric c-spine CT examinations. Pediatric hospitals practice at lower CT dose estimates than other hospitals. Individual hospitals should examine their practices in an effort to ensure standardization and optimization of CT parameters to minimize radiation exposures to pediatric patients.

Written Informed Consent for Computed Tomography of the Abdomen/Pelvis is Associated with Decreased CT Utilization in Low-Risk Emergency Department Patients

INTRODUCTION

The increasing rate of patient exposure to radiation from computerized tomography (CT) raises questions about appropriateness of utilization. There is no current standard to employ informed consent for CT (ICCT). Our study assessed the relationship between informed consent and CT utilization in emergency department (ED) patients.

METHODS

An observational multiphase before-after cohort study was completed from 4/2010-5/2011. We assessed CT utilization before and after (Time I/Time II) the implementation of an informed consent protocol. Adult patients were included if they presented with symptoms of abdominal/pelvic pathology or completed ED CT. We excluded patients with pregnancy, trauma, or altered mental status. Data on history, exam, diagnostics, and disposition were collected via standard abstraction tool. We generated a multivariate logistic model via stepwise regression, to assess CT utilization across risk groups. Logistic models, stratified by risk, were generated to include study phase and a propensity score that controlled for potential confounders of CT utilization.

RESULTS

7,684 patients met inclusion criteria. In PHASE 2, there was a 24% (95% CI [10-36%]) reduction in CT utilization in the low-risk patient group (p<0.002). ICCT did not affect CT utilization in the high-risk group (p=0.16). In low-risk patients, the propensity score was significant (p<0.001). There were no adverse events reported during the study period.

CONCLUSION

The implementation of ICCT was associated with reduced CT utilization in low-risk ED patients. ICCT has the potential to increase informed, shared decision making with patients, as well as to reduce the risks and cost associated with CT.

Improving Procedure Start Times and Decreasing Delays in Interventional Radiology: A Department's Quality Improvement Initiative

RATIONALE AND OBJECTIVES

To identify and reduce reasons for delays in procedure start times, particularly the first cases of the day, within the interventional radiology (IR) divisions of the Department of Radiology using principles of continuous quality improvement.

MATERIALS AND METHODS

An interdisciplinary team representative of the IR and preprocedure/postprocedure care area (PPCA) health care personnel, managers, and data analysts was formed. A standardized form was used to document both inpatient and outpatient progress through the PPCA and IR workflow in six rooms and to document reasons for delays. Data generated were used to identify key problems areas, implement improvement interventions, and monitor their effects. Project duration was 6 months.

RESULTS

The average number of on-time starts for the first case of the day increased from 23% to 56% (P value < .01). The average number of on-time, scheduled outpatients increased from 30% to 45% (P value < .01). Patient wait time to arrive at treatment room once they were ready for their procedure was reduced on average by 10 minutes (P value < .01). Patient care delay duration per 100 patients was reduced from 30.3 to 21.6 hours (29% reduction). Number of patient care delays per 100 patients was reduced from 46.6 to 40.1 (17% reduction). Top reasons for delay included waiting for consent (26% of delays duration) and laboratory tests (12%).

CONCLUSIONS

Many complex factors contribute to procedure start time delays within an IR practice. A data-driven and patient-centered, interdisciplinary team approach was effective in reducing delays in IR.

Advancing Patient-centered Outcomes in Emergency Diagnostic Imaging: A Research Agenda

Diagnostic imaging is integral to the evaluation of many emergency department (ED) patients. However, relatively little effort has been devoted to patient-centered outcomes research (PCOR) in emergency diagnostic imaging. This article provides background on this topic and the conclusions of the 2015 Academic Emergency Medicine consensus conference PCOR work group regarding "Diagnostic Imaging in the Emergency Department: A Research Agenda to Optimize Utilization." The goal was to determine a prioritized research agenda to establish which outcomes related to emergency diagnostic imaging are most important to patients, caregivers, and other key stakeholders and which methods will most optimally engage patients in the decision to undergo imaging. Case vignettes are used to emphasize these concepts as they relate to a patient's decision to seek care at an ED and the care received there. The authors discuss applicable research methods and approaches such as shared decision-making that could facilitate better integration of patient-centered outcomes and patient-reported outcomes into decisions regarding emergency diagnostic imaging. Finally, based on a modified Delphi process involving members of the PCOR work group, prioritized research questions are proposed to advance the science of patient-centered outcomes in ED diagnostic imaging.

A Comprehensive CT Dose Reduction Program Using the ACR Dose Index Registry

PURPOSE

The purpose of this article is to demonstrate the role of the ACR Dose Index Registry(®) (DIR) in a dose reduction program at a large academic health care system.

METHODS

Using the ACR DIR, radiation doses were collected for four common CT examination types (head without contrast, chest with contrast, chest without contrast, and abdomen and pelvis with contrast). Baseline analysis of 7,255 CT examinations from seven scanners across the institution was performed for the period from December 1, 2011, to March 15, 2012. A comprehensive dose reduction initiative was guided by the identification of targets for dose improvement from the baseline analysis. Data for 14,938 examinations from the same seven scanners were analyzed for the postimplementation period of January 1, 2013, to July 1, 2013.

RESULTS

The program included protocol changes, iterative reconstruction, optimization of scan acquisition, technologist education, and continuous monitoring with feedback tools. Average decrease in median dose-length product (DLP) across scanners was 30% for chest CT without contrast, 29% for noncontrast head CT, 26% for abdominal and pelvic CT with contrast, and 10% for chest CT with contrast. Compared with average median DLP in the ACR DIR, the median institution-wide CT DLPs after implementation were lower by 33% for chest CT without contrast, 32% for chest CT with contrast, 26% for abdominal and pelvic CT with contrast, and 6% for head CT without contrast.

CONCLUSIONS

A comprehensive CT dose reduction program using the ACR DIR can lead to substantial dose reduction within a large health care system.

Hospital-level factors associated with use of pediatric radiation dose-reduction protocols for head CT: results from a national survey

OBJECTIVES

To examine hospital-level factors associated with the use of a dedicated pediatric dose-reduction protocol and protective shielding for head CT in a national sample of hospitals.

METHODS

A mixed-mode (online and paper) survey was administered to a stratified random sample of US community hospitals (N = 751). Respondents provided information on pediatric head CT scanning practices, including use of a dose-reduction protocol. Modified Poisson regression analyses describe the relative risk (RR) of not reporting the use of a pediatric dose-reduction protocol or protective shielding; multivariable analyses adjust for census region, trauma level, children's hospital status, and bed size.

RESULTS

Of hospitals that were contacted, 38 were ineligible (no CT scanner, hospital closed, do not scan infants), 1 refused, and 253 responded (35.5% response rate). Across all hospitals, 92.6% reported using a pediatric dose-reduction protocol. Modified Poisson regression showed that small hospitals (0-50 beds) were 20% less likely to report using a protocol than large hospitals (>150 beds) (RR: 0.80, 95% confidence interval [CI]: 0.65-0.99; adjusted for covariates). Teaching hospitals were more likely to report using a protocol (RR: 1.10, 95% CI: 1.02-1.19; adjusted for covariates). After adjusting for covariates, children's hospitals were significantly less likely to report using protective shielding than nonchildren's hospitals (RR: 0.64, 95% CI: 0.56-0.73), though this may be due to more advanced scanner type.

CONCLUSION

Results from this study provide guidance for tailored educational campaigns and quality improvement interventions to increase the adoption of pediatric dose-reduction efforts.

Protection of patients in diagnostic and interventional medical imaging: collaboration is the key

The radiology community (medical physicists, radiologic technologists, radiologists, and interventional proceduralists) has led the educational and awareness efforts in the medical arena to reduce radiation dose to patients through effective collaborations that bridge traditional medical specialty silos to reach health worker stakeholders. These successful collaborations have also included both vendors and regulators, with the overarching goal of radiation protection of patients (justification, optimization, and use of dose reference levels). This focus on patients often raises overall safety awareness and lowers occupational radiation doses as well. It is critical that the entire radiology community continue to act as leaders in these radiation safety efforts for both employees and patients. In order to be successful, it is important to understand safety culture and the growing, worldwide, multimedia resources that are available. There is little time or budget to recreate or duplicate training materials or risk communication information that may already exist. Together with the increasingly fast-paced and demanding healthcare environment and sharp focus on quality, it has never been more important to understand how to achieve better quality care for radiology departments. It is also important to measure and report quality for many customers, including patients, referring providers, and many other stakeholders. This short report will briefly define safety culture and describe methods for using collective learning tools that document radiation protection of patients in diagnostic and interventional imaging. These tools include the use of imaging modality registries, such as the Computed Tomography Does Index Registry, peer review of imaging reports, the use of clinical decision support, and guidelines. Finally, the Image Gently and Image Wisely campaigns provide examples of cross-disciplinary collaboration to improve radiation protection of patients.

Adapting to the new radiology landscape: challenges and solutions discussed at the 2014 AMCLC open-microphone sessions

Every year, multiple open-microphone sessions are hosted at the ACR AMCLC. These sessions allow members of the College to offer opinions, experiences, and questions regarding challenges facing radiologists and the future of the profession. At the 2014 AMCLC, 3 such sessions focused, respectively, on radiology's workforce, the obstacles slowing the shift from volume to value, and alternative reimbursement models and the shifting physician employment landscape. These open-microphone sessions framed contemporary obstacles and emerging challenges that professional radiology societies, such as the ACR, should target with new initiatives and use of resources; in addition, the sessions revealed opportunities for members, councilors, and state chapters to respond with meaningful resolutions and policy proposals.

Cumulative radiation exposure estimates of hospitalized patients from radiological imaging

PURPOSE

To examine the use of inpatient diagnostic imaging and image-guided procedures to estimate cumulative radiation exposure, radiation exposure based on imaging modality, and compare estimated doses based on patient demographics including age, gender, and diagnoses.

METHODS

Two hundred consecutive hospitalized adult patients who underwent diagnostic imaging studies at 2 large, affiliated hospitals were identified, and every study in each patient's electronic record that took place during a single hospitalization was reviewed. Dose estimates were calculated for each CT, fluoroscopy, nuclear medicine, plain film, and interventional radiology study or procedure based on reported dose length product, published reference values, and conversion factors. Medical records were reviewed to determine patient gender, age, diagnoses, length of stay, admitting service, and time in an intensive care unit (ICU).

RESULTS

Two hundred inpatients (46.5% male; mean age, 60.4 years) underwent 2,751 imaging studies (79.3% radiographs, 9.7% CT, 6.1% ultrasound, 2.5% interventional radiology, 2.2% MRI, 0.4% nuclear medicine). The mean dose estimate per patient was 14.8 milliSieverts (mSv) and the range was 0 mSv to 130.5 mSv. Mean cumulative dose estimates were significantly higher for patients whose hospitalizations included time in an ICU (17.9 mSv versus 11.3 mSv [P = .01]). CT examinations accounted for 82.1% of the total radiation dose estimate. Eleven patients (5.5%) received radiation dose estimates ≥ 50 mSv, including 2 ≥ 100 mSv.

CONCLUSIONS

Of imaged inpatients, 62% underwent at least 1 CT and the majority (82.1%) of inpatient radiation exposure was attributable to CT examinations. Mean dose estimate was 14.8 mSv per patient; 5.5% of patients experienced estimated doses ≥ 50 mSv.

Fluoroscopic-guided lumbar puncture: fluoroscopic time and implications of body mass index--a baseline study

BACKGROUND AND PURPOSE

Fluoroscopic-guided lumbar puncture is an effective alternative to bedside lumbar puncture in challenging patients. However, no published guidelines are available for an acceptable range of fluoroscopic time for this procedure. The purpose of this study was to set department benchmark fluoroscopic times for lumbar puncture, accounting for body mass index in our patient population.

MATERIALS AND METHODS

We identified and reviewed all patients who underwent fluoroscopic-guided lumbar puncture at 4 hospitals during a 2-year period (July 2011 to June 2013). Data collection included patient information (demographics, body mass index, history of prior lumbar surgery and/or lumbar hardware, scoliosis); procedure details (fluoroscopic time, level of access, approach, needle gauge and length); level of operator experience; and hospital site. A generalized linear model was used to test whether body mass index influenced fluoroscopic time while controlling other factors.

RESULTS

Five hundred eighty-four patients (mean age, 47.8 ± 16.2 years; range, 16-92 years; 33% male) had successful fluoroscopic-guided lumbar puncture s. Mean body mass index and fluoroscopic time were higher in female patients (34.4 ± 9.9 kg/m(2) and 1.07 minutes; 95% CI, 0.95-1.20) than in male patients (29.2 ± 7.3 kg/m(2) and 0.91 minutes; 95% CI, 0.79-1.03). Body mass index (P = .001), hospital site (P < .001), and level of experience (P = .03) were factors significantly affecting fluoroscopic time on multivariate analysis. Benchmark fluoroscopic times in minutes were the following: 0.48 (95% CI, 0.40-0.56) for normal, 0.61 for overweight (95% CI, 0.52-0.71), 0.63(95% CI, 0.58-0.73) for obese, and 0.86 (95% CI, 0.74-1.01) in extremely obese body mass index categories.

CONCLUSIONS

In patients undergoing fluoroscopic-guided lumbar punctures, fluoroscopy time increased with body mass index We established benchmark fluoroscopic-guided lumbar puncture time ranges as related to body mass index in our patient population.

Comparative accuracy of intravenous contrast-enhanced CT versus noncontrast CT plus intravenous contrast-enhanced CT in the detection and characterization of patients with hypervascular liver metastases: a critically appraised topic

RATIONAL AND OBJECTIVES

To evaluate whether addition of nonenhanced computed tomography (NECT) to intravenous contrast-enhanced (CE) abdominal CT improves detection or characterization of hypervascular liver masses. Patients were referred for initial staging or follow-up with known breast, melanoma, neuroendocrine, or thyroid cancer.

MATERIAL AND METHODS

The literature was searched using the patient, intervention, comparison, and outcome (PICO) method. Retrieved articles were critically appraised and assigned a level of evidence based on the Oxford University Centre for Evidence-based Medicine hierarchy of validity for diagnostic studies.

RESULTS

One thousand one hundred studies were reviewed; only 11 studies matched the PICO of our study and were appraised. Most of the appraised articles were published in the 1990s using older technology and contrast delivery. The retrieved diagnostic performance for characterization of liver metastases showed sensitivity/specificity of 97%/76% for NECT, 97%/75% for arterial CT, and 98%/76% for portal venous phase CT in patients with breast cancer; sensitivity of 96% (arterial and portal CT) versus 100% (NECT, arterial and portal CT) in patients with melanoma; and sensitivity of 43% (portal CT) versus 17% (NECT) in patients with neuroendocrine tumor. No primary study was found for performance of different CT protocols in patients with thyroid cancer. Available evidence showed radiologists reported more conspicuous liver masses on CECT compared to NECT in patients with breast or neuroendocrine cancer.

CONCLUSIONS

Based on existing evidence, NECT only adds a small incremental value to CECT for detection/characterization of hypervascular liver metastases. Addition of NECT increases patient's exposure to radiation and the number of images available for interpretation.

Clinical practice guideline for the diagnosis and management of acute bacterial sinusitis in children aged 1 to 18 years

OBJECTIVE

To update the American Academy of Pediatrics clinical practice guideline regarding the diagnosis and management of acute bacterial sinusitis in children and adolescents.

METHODS

Analysis of the medical literature published since the last version of the guideline (2001).

RESULTS

The diagnosis of acute bacterial sinusitis is made when a child with an acute upper respiratory tract infection (URI) presents with (1) persistent illness (nasal discharge [of any quality] or daytime cough or both lasting more than 10 days without improvement), (2) a worsening course (worsening or new onset of nasal discharge, daytime cough, or fever after initial improvement), or (3) severe onset (concurrent fever[temperature ≥39°C/102.2°F] and purulent nasal discharge for at least 3 consecutive days). Clinicians should not obtain imaging studies of any kind to distinguish acute bacterial sinusitis from viral URI, because they do not contribute to the diagnosis; however, a contrast-enhanced computed tomography scan of the paranasal sinuses should be obtained whenever a child is suspected of having orbital or central nervous system complications. The clinician should prescribe antibiotic therapy for acute bacterial sinusitis in children with severe onset or worsening course. The clinician should either prescribe antibiotic therapy or offer additional observation for 3 days to children with persistent illness. Amoxicillin with or without clavulanate is the firstline treatment of acute bacterial sinusitis. Clinicians should reassess initial management if there is either a caregiver report of worsening(progression of initial signs/symptoms or appearance of new signs/symptoms) or failure to improve within 72 hours of initial management.If the diagnosis of acute bacterial sinusitis is confirmed in a child with worsening symptoms or failure to improve, then clinicians may change the antibiotic therapy for the child initially managed with antibiotic or initiate antibiotic treatment of the child initially managed with observation.

CONCLUSIONS

Changes in this revision include the addition of a clinical presentation designated as “worsening course,” an option to treat immediately or observe children with persistent symptoms for 3 days before treating, and a review of evidence indicating that imaging is not necessary in children with uncomplicated acute bacterial sinusitis.

Image Gently: a campaign to reduce children's and adolescents' risk for cancer during adulthood

Recently, the Cancer Prevention Across the Lifespan workgroup at the Centers for Disease Control held a workshop entitled "Identifying Opportunities for Cancer Prevention During Pre-Adolescence and Adolescence." With the goal of raising awareness and developing community and policy interventions to decrease risk factors for cancer, one session highlighted the danger of ionizing radiation exposure from diagnostic medical imaging. This session focused on the Image Gently campaign, which is a multidisciplinary partnership focused on increasing awareness, developing education materials, and advocating for children to protect them from unnecessary radiation. Such protection is important because emerging data suggest that preadolescents and adolescents may be at increased risk for future malignancy if they are exposed to radiation from diagnostic imaging. Many health care practitioners may not understand how to decrease children's radiation exposure; the goals of Image Gently are to increase all stakeholders' understanding of these risks and to encourage radiation reduction strategies. Clearly, diagnostic imaging is an important and necessary tool for certain medical care. Image Gently advocates methods to reduce the use of unnecessary ionizing radiation by sharing best practices of imaging protocols for children and using alternative imaging that avoids ionizing radiation. This article summarizes our recent presentation on Image Gently to this workgroup: It focuses on the risks for preadolescents and adolescents and on strategies to minimize these risks.

Rate of detection of unsuspected pregnancies after implementation of mandatory point-of-care urine pregnancy testing prior to hysterosalpingography

PURPOSE

The aim of this study was to determine the rate of detection of unsuspected pregnancies after the implementation of mandatory point-of-care urine pregnancy testing before hysterosalpingography (HSG).

METHODS

At the authors' institution, HSGs are scheduled to occur during days 8 to 12 of the menstrual cycle. Upon arrival in the radiology department, all women undergo point-of-care urine pregnancy testing before HSG (at a cost of $1.25 per test). Urine pregnancy test results were retrospectively reviewed.

RESULTS

Four hundred ten women (mean age, 25.9 years; range, 22-50 years) underwent point-of-care urine pregnancy testing before HSG between October 2010 and July 2012. Study indications were infertility evaluation (90.7% [372 of 410]) and tubal patency assessment after placement of tubal occlusive devices (9.3% [38 of 410]). Two positive urine pregnancy test results (0.5%) were recorded. One positive result was deemed a false-positive because the patient had received an intramuscular injection of β-human chorionic gonadotropin before the scheduled HSG, and follow-up laboratory testing showed declining β-human chorionic gonadotropin levels. The second positive result was a true-positive, and the patient was determined to be 4.5 weeks pregnant on the date of the scheduled HSG.

CONCLUSIONS

One of 410 women presenting for HSG was found to have an unsuspected early pregnancy, which was detected with a point-of-care urine pregnancy test. Consideration should be given to routine pregnancy testing of women before HSG because scheduling on the basis of menstrual cycle dates can be unreliable.

From guidelines to practice: how reporting templates promote the use of radiology practice guidelines

Radiology practice guidelines have been developed to help radiologists achieve quality and safety in their clinical practice. One means to promote the use of practice guidelines in radiology is through the wider use of reporting templates, also known as "structured reporting." This article presents specific examples in which radiology reporting templates can promote adherence to guidelines, gather data for quality improvement efforts, and facilitate compliance with performance incentive programs.

Imaging and insurance: do the uninsured get less imaging in emergency departments?

PURPOSE

On average, Americans without health insurance receive fewer health care services than those with insurance. The specific types of services for which the uninsured face access and utilization deficits are not well understood. The authors describe the use of imaging tests in hospital emergency departments (EDs) by nonelderly patients, comparing uninsured, Medicaid, and non-Medicaid insured individuals.

METHODS

The main database used was the 2004 National Hospital Ambulatory Medical Care Survey. The survey contained 2 fields critical to the study: source of payment and imaging services rendered during the ED visit. Source of payment was used to sort ED visit episodes into 3 insurance categories: uninsured, Medicaid, and non-Medicaid insured. Relative value units were assigned to imaging procedures. Imaging procedures were aggregated into 6 modalities. Univariate and multivariate methods were used to compare the number of imaging procedures and associated relative value units across insurance categories. Risk adjustment used the immediacy code, reason for visit, disposition, and demographics.

RESULTS

Compared with comparable insured persons, nonelderly uninsured and Medicaid patients received fewer services in the ED (8% and 10%, respectively, P < .01), even after adjustment for level of acuity. Similar results were found for the value of imaging services received (13% and 19%, respectively, P < .01).

CONCLUSIONS

These results suggest that insurance status influences how much imaging and the intensity of imaging patients receive. Further research is needed to understand whether insured patients receive unnecessary imaging or if uninsured and Medicaid patients receive too little imaging.

Global quality imaging: emerging issues

Quality imaging may be described as "a timely access to and delivery of integrated and appropriate procedures, in a safe and responsive practice, and a prompt delivery of an accurately interpreted report by capable personnel in an efficient, effective, and sustainable manner." For this article, radiation safety is considered as one of the key quality elements. The stakeholders are the drivers of quality imaging. These include those that directly provide or use imaging procedures and others indirectly supporting the system. Imaging is indispensable in health care, and its use has greatly expanded worldwide. Globalization, consumer sophistication, communication and technological advances, corporatization, rationalization, service outsourcing, teleradiology, workflow modularization, and commoditization are reshaping practice. This article defines the emerging issues; an earlier article in the May 2011 issue described possible improvement actions. The issues that could threaten the quality use of imaging for all countries include workforce shortage; increased utilization, population radiation exposure, and cost; practice changes; and efficiency drive and budget constraints. In response to these issues, a range of quality improvement measures, strategies, and actions are used to maximize the benefits and minimize the risks. The 3 measures are procedure justification, optimization of image quality and radiation protection, and error prevention. The development and successful implementation of such improvement actions require leadership, collaboration, and the active participation of all stakeholders to achieve the best outcomes that we all advocate.