Abdominal imaging utilization in the emergency department: trends over two decades

The utility of the abdominal series in the emergency setting: a retrospective review

PURPOSE

The abdominal series (AXR) remains a frequently ordered test in the emergency department (ED), despite existing literature questioning its utility. The aim of this study was to characterize the use of the AXR in the ED by quantifying how often it is ordered and the frequency of subsequent imaging. Additionally, a time estimate in ED associated with the AXR was quantified. We hypothesized that there would be a low clinical utility of the AXR, and long associated time period spent in the ED.

METHODS

A retrospective audit of AXRs performed in the ED from January to December 2019 was performed. The local picture archiving and communication system (PACS) and electronic medical record were used to collect the variables.

RESULTS

Of 701 AXRs, 438 (62.4%) were reported normal, and 263 (37.6%) were abnormal. A Chi Squared test showed that the two variables (abdominal series result and follow up imaging completion) were significantly related, with p < 0.001. However, the effect size was small (Nagelkerke R square = 0.022). The average time spent in the ED for these patients was 7.27 h, and the average time between the AXR being ordered and interpreted was 1.31 h.

CONCLUSION

The majority of AXRs were reported as normal. Our results showed that AXR had a statistically significant, but low clinically significant predictive ability on subsequent imaging ordering. This supports our hypothesis that the AXR is of low clinical utility with respect to the rate of ordering follow up imaging. The AXR also translated to a quantifiable time interval during the patient's stay in ED. Minimizing overuse of the AXR may result in a decrease in patient duration in the ED.

Gallstones Detection on Dual-Energy Computerized Tomography-Is It Ready for Real-World Use? A Retrospective Observational Study

AIMS

The aims of the study are to evaluate the performance of dual-energy computed tomography (DECT) imaging in the detection of noncalcified gallstones (GSs) and to assess its performance relative to transabdominal ultrasound (US) in identifying cholelithiasis.

METHOD

This study is a retrospective review of radiology records and images to find all patients who had both US and DECT scans within a 6-month period and were found to have GSs. Patients who did not have GSs on US served as the control group. The CT scans were reviewed by 4 radiologists who did not have access to the US results when assessing the presence or absence of GSs on the DECT scans. In case of any discrepancies among the radiologists, the majority opinion was considered. If there was a split opinion, a fifth reviewer was consulted. The data were analyzed to calculate sensitivity, specificity, positive and negative predictive values, as well as overall accuracy and to evaluate interreader variability. The absolute Hounsfield unit (HU) differences of the GSs and bile were compared between polychromatic (PC), virtual noncontrast (VNC), and virtual monochromatic (VMC) images.

RESULTS

Considering at least 3-reader agreement, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were found to be 92%, 96%, 96%, 92%, and 94%, respectively. Individual reader sensitivity varied between 87% and 92%. There was good interobserver agreement with a Fleiss' kappa of 0.76. Quantification of the whole data set showed that no significant difference was observed in the HU values for the stones between the PC images and the VNC images. A significant increase was observed on the 50-keV VMC images compared with the PC and VNC images. In the study group, 17% stones were visualized only on the VNC or/and 50-keV VMC images, and not on the PC images. On quantitative analysis of these cases, there was a significant increase of HU in the VNC images as compared with PC images and a significant decrease of HU in the 50-keV VMC images as compared with PC images.

CONCLUSIONS

Low-keV images increase stone-bile contrast. Evaluation of cholelithiasis using VNC and 50-keV VMC images demonstrated a 14% increase in sensitivity relative to conventional CT.

Evaluation of Abdominal Emergencies

Early primary assessment and abdominal examination can often be enough to triage the patient with abdominal pain into those with less severe underlying pathologic condition from those with more acute findings. A focused history of the patient can then allow the clinician to develop their differential diagnosis. Once the differential diagnoses are determined, diagnostic imaging and laboratory findings can help confirm the diagnosis and allow for expeditious treatment and intervention.

Factors contributing to uncertainty in paediatric abdominal ultrasound reports in the paediatric emergency department

BACKGROUND

Abdominal pain, which is a common cause of children presenting to the paediatric emergency department (PED), is often evaluated by ultrasonography (US). However, uncertainty in US reports may necessitate additional imaging.

OBJECTIVE

In this study, we evaluated factors contributing to uncertainty in paediatric abdominal US reports in the PED.

MATERIALS AND METHODS

This retrospective cohort study included children younger than 18 years of age who underwent abdominal US in the PED of the study hospital between January 2017 and December 2019. After exclusion, the researchers manually reviewed and classified all US reports as 'certain' or 'uncertain'. Univariate and multivariate logistic regression analyses were performed to identify the factors contributing to uncertain reports.

RESULTS

In total, 1006 patients were included in the final analysis., 796 patients were tagged as having certain reports, and 210 as having uncertain reports. Children with uncertain reports had a significantly higher rate of undergoing an additional computed tomography (CT) scan (31.0% vs. 2.5%, p < 0.001) and a longer PED median length of stay (321.0 (Interquartile range (IQR); 211.3-441.5) minutes vs. 284.5 (IQR; 191.8-439.5) minutes, p = 0.042). After logistic regression, US performed by a radiology resident (odds ratio, 5.01; 95% confidence interval, 3.63-7.15) was the most significant factor contributing to uncertainty in paediatric abdominal US reports followed by obesity and age.

CONCLUSION

Several factors contribute to uncertainty in paediatric abdominal US reports. Uncertain radiological reports increase the likelihood of additional CT scans. Measures to improve the clarity of radiological reports must be considered to improve the quality of care for children visiting the PED.

Real-world accuracy of computed tomography in patients admitted with small bowel obstruction: a multicentre prospective cohort study

PURPOSE

Small bowel obstruction (SBO) is a common surgical emergency. Previous studies have shown the value computed tomography (CT) scanning in both confirming this diagnosis and identifying indications for urgent surgical intervention, such as strangulated bowel or closed loop obstructions. However, most of the literature is based on retrospective expert review of previous imaging and little data regarding the real-time accuracy of CT reporting is available. Here, we investigated the real-world accuracy of CT reporting in patients admitted with SBO.

METHODS

This was a multicentre prospective study including consecutive patients admitted with SBO. The primary outcomes were the sensitivity and specificity of CT scanning for bowel obstruction with ischaemia and closed loop obstruction. Data were retrieved from the original CT reports written by on-call radiologists and compared with operative findings.

RESULTS

One hundred seventy-six patients were included, all of whom underwent CT scanning with intravenous contrast followed by operative management of SBO. Bowel obstruction with ischaemia was noted in 20 patients, with a sensitivity and specificity of CT scanning of 40.0% and 85.5%, respectively. Closed loop obstructions were noted in 26 patients, with a sensitivity and specificity of CT scanning of 23.1% and 98.0%, respectively.

CONCLUSIONS

The real-world accuracy of CT scanning appears to be lower than previously reported in the literature. Strategies to address this could include the development of standardised reporting schemas and to increase the surgeon's own familiarity with relevant CT features in patients admitted with SBO.

Developing a decision instrument to guide abdominal-pelvic imaging of blunt trauma patients: Methodology and protocol of the NEXUS abdominal-pelvic imaging study

Although computed tomography (CT) of the abdomen and pelvis (A/P) can provide crucial information for managing blunt trauma patients, liberal and indiscriminant imaging is expensive, can delay critical interventions, and unnecessarily exposes patients to ionizing radiation. Currently no definitive recommendations exist detailing which adult blunt trauma patients should receive A/P CT imaging and which patients may safely forego CT. Considerable benefit could be realized by identifying clinical criteria that reliably classify the risk of abdominal and pelvic injuries in blunt trauma patients. Patients identified as “very low risk” by such criteria would be free of significant injury, receive no benefit from imaging and therefore could be safely spared the expense and radiation exposure associated with A/P CT. The goal of this two-phase nationwide multicenter observational study is to derive and validate the use of clinical criteria to stratify the risk of injuries to the abdomen and pelvis among adult blunt trauma patients. We estimate that nation-wide implementation of a rigorously developed decision instrument could safely reduce CT imaging of adult blunt trauma patients by more than 20%, and reduce annual radiographic charges by $180 million, while simultaneously expediting trauma care and decreasing radiation exposure with its attendant risk of radiation-induced malignancy. Prior to enrollment we convened an expert panel of trauma surgeons, radiologists and emergency medicine physicians to develop a consensus definition for clinically significant abdominal and pelvic injury. In the first derivation phase of the study, we will document the presence or absence of preselected candidate criteria, as well as the presence or absence of significant abdominal or pelvic injuries in a cohort of blunt trauma victims. Using recursive partitioning, we will examine combinations of these criteria to identify an optimal “very low risk” subset that identifies injuries with a sensitivity exceeding 98%, excludes injury with a negative predictive value (NPV) greater than 98%, and retains the highest possible specificity and potential to decrease imaging. In Phase 2 of the study we will validate the performance of a decision rule based on these criteria among a new cohort of patients to ensure that the criteria retain high sensitivity, NPV and optimal specificity. Validating the sensitivity of the decision instrument with high statistical precision requires evaluations on 317 blunt trauma patients who have significant abdominal-pelvic injuries, which will in turn require evaluations on approximately 6,340 blunt trauma patients. We will estimate potential reductions in CT imaging by counting the number of abdominal-pelvic CT scans performed on “very low risk” patients. Reductions in charges and radiation exposure will be determined by respectively summing radiographic charges and lifetime decreases in radiation morbidity and mortality for all “very low risk” cases.

Trial registration: Clinicaltrials.gov trial registration number: NCT04937868.

Incidental Radiology Findings on Computed Tomography Studies in Emergency Department Patients: A Systematic Review and Meta-Analysis

STUDY OBJECTIVE

An incidental finding is defined as a newly discovered mass or lesion detected on imaging performed for an unrelated reason. The identification of an incidental finding may be an opportunity for the early detection of a serious medical condition, including a malignancy. However, little is known about the prevalence of incidental findings in the emergency department (ED) setting and the strategies that can be used to mitigate the risk associated with them in the ED. This study aimed to estimate the overall prevalence of incidental findings and to summarize the currently described measures to mitigate the risks associated with incidental findings.

METHODS

On November 22, 2020, a systematic literature search of PubMed, EMBASE, and Scopus was performed for studies that were published in peer-reviewed journals and reported the prevalence of incidental findings in computed tomography (CT) scans in patients in the ED. Patients who received CT scans that included the head, neck, chest, or abdomen/pelvis were included. The study characteristics, overall prevalence of incidental findings, prevalence of incidental findings by body region, and prespecified subgroups were extracted. The criteria used for risk stratification within individual studies were also extracted. Pooled estimates were calculated using a random-effects meta-analysis.

RESULTS

A total of 1,385 studies were identified, and 69 studies met the inclusion criteria. The included studies represented 147,763 ED encounters or radiology reports across 16 countries, and 83% of studies were observational, cross-sectional studies. A total of 35 studies (50.7%) were in trauma patients. A large degree of heterogeneity was observed across the included studies. The overall pooled prevalence estimate for any incidental finding was 31.3% (95% confidence interval 24.4% to 39.1%). We found great variation in the methods described to mitigate the risk associated with incidental findings, including a lack of standardized risk stratification, inconsistent documentation practices, and only a small subset of studies describing prospective interventions aimed at improving the recognition and management of incidental findings from the ED.

CONCLUSION

In patients in the ED receiving CT scans, incidental findings are commonly encountered across a broad range of ED chief complaints. This review highlights the existence of great heterogeneity in the definitions used to classify incidental findings. Future studies are needed to determine a clinically feasible categorization standard or terminology for commonly encountered incidental findings in the ED setting to standardize classification and documentation.

Prevalence of imaging findings of acute pancreatitis in emergency department patients with elevated serum lipase

PURPOSE

To assess the association of imaging features of acute pancreatitis (AP) with the magnitude of lipase elevation in Emergency Department (ED) patients.

METHODS

This Institutional Review Board-approved retrospective study included 509 consecutive patients presenting from 9/1/13-8/31/15 to a large academic ED with serum lipase levels ≥3× the upper limit of normal (ULN) (≥180 U/L). Patients were excluded if they did not have imaging (n = 131) or had a history of trauma, abdominal metastases, altered mental status, or transfer from an outside hospital (n = 190); the final study population was 188 patients. Imaging exams were retrospectively evaluated, and a consensus opinion of two subspecialty-trained abdominal radiologists was used to diagnose AP. Primary outcome was presence of imaging features of AP stratified by lipase level (≥3×-10× ULN and > 10× ULN). Secondary outcome was rate of discordant consensus evaluation compared to original radiologist's report.

RESULTS

25.0% of patients (47/188) had imaging features of AP. When lipase was >10× ULN (n = 94), patients were more likely to have imaging features of AP (34%) vs. those with mild elevation (16%) (p = 0.0042). There was moderately strong correlation between lipase level and presence of imaging features of AP (r = 0.48, p < 0.0001). Consensus review of CT and MRI images was discordant with the original report in 14.9% (28/188) of cases.

CONCLUSION

Prevalence of imaging signs of AP in an ED population with lipase ≥3× ULN undergoing imaging is low. However, the probability of imaging features of AP increases as lipase value increases.

Effect of COVID-19 on computed tomography usage and critical test results in the emergency department: an observational study

BACKGROUND

The effect of the coronavirus disease 2019 (COVID-19) pandemic on new or unexpected radiologic findings in the emergency department (ED) is unclear. The aim of this study was to determine the effect of the COVID-19 pandemic on the number of computed tomography (CT) critical test results in the ED.

METHODS

We performed a retrospective observational study of ED CT usage at 4 Ontario hospitals (1 urban academic, 1 northern academic, 1 urban community and 1 rural community) over 1 month during the COVID-19 pandemic (April 2020) and over the same month 1 year earlier (April 2019; before the pandemic). The CT findings from 1 of the 4 hospitals, Hamilton Health Sciences, were reviewed to determine the number of critical test results by body region. Total CT numbers were compared using Poisson regression and CT yields were compared using the χ² test.

RESULTS

The median number of ED CT examinations per day was markedly lower during the COVID-19 pandemic than before the pandemic (82 v. 133, p < 0.01), with variation across hospitals (p = 0.001). On review of 1717 CT reports from Hamilton Health Sciences, fewer critical test results were demonstrated on CT pulmonary angiograms (43 v. 88, p < 0.001) and CT examinations of the head (82 v. 112, p < 0.03) during the pandemic than before the pandemic; however, the yield of these examinations did not change. Although the absolute number of all CT examinations with critical test results decreased, the number of CT examinations without critical results decreased more, resulting in a higher yield of CT for critical test results during the pandemic (46% [322/696] v. 37% [379/1021], p < 0.01).

INTERPRETATION

Emergency department CT volumes markedly decreased during the COVID-19 pandemic, predominantly because there were fewer examinations with new or unexpected findings. This suggests that COVID-19 public information campaigns influenced the behaviours of patients presenting to the ED.

Use of CT Scans for Abdominal Pain in the ED: Factors in Choice

Overutilization of healthcare resources is a threat to long-term healthcare sustainability and patient outcomes. CTis a costly but efficient means of assessing abdominal pain; however, 97 per cent of ED physicians acknowledge its overutilization. This study sought to understand factors that influence ED providers’ decision regarding CT use in the evaluation of abdominal pain. After evaluating a patient for acute abdominal pain, ED providers filled in a form in which the primary diagnosis and index of suspicion were recorded. Bivariate and multivariate analyses were used to identify predictors of outcomes. The CT scan utilization rate was 54.82 per cent. Whereas 34.11 per cent of CT scans were normal, 30 per cent yielded an acute abdominal pathology. Tenderness and rebound tenderness were positive predictors of high index of suspicion [odds ratio (OR) 2.09 and 2.54, respectively]. These variables were also predictive of obtaining a CT scan [OR 2.64 and 3.41, respectively]. Compared with whites, the index of suspicion was 26 per cent and 56 per cent less likely to be high when patients were black [OR 0.73] or Hispanic [OR 0.44] respectively. Blacks and Hispanics were less likely to have CT scans performed than whites [OR 0.58 and 0.48, respectively]. Leukocytosis significantly affected the index of suspicion for acute abdominal pathology, obtaining a CTscan and the acuity of CTscan diagnosis on multivariate analysis. Patients aged ≥60 years had 2.03 odds of acute CT finding compared with those aged <60 years. There is a need for committed efforts to optimize CT scan utilization and eliminate socioeconomic disparities in health care.

The prevalence of pathological findings identified by next day abdominal ultrasound in patients discharged from the emergency department

OBJECTIVE

A common strategy for managing emergency department (ED) patients with low-risk abdominal pain is to discharge them home and arrange for next day outpatient ultrasound for further assessment. The objective was to determine the proportion of outpatient ultrasounds with findings requiring intervention within 14 days.

METHODS

This was a retrospective chart review of non-pregnant patients ages 18 to 40 years, presenting to an academic ED (annual census 65,000) with an abdominal complaint for whom the emergency physician arranged an outpatient (next day) abdominal ultrasound.

RESULTS

Of the 299 included patients, 252 (84.3%) were female and mean (SD) age was 28.4 (6.0) years. Twenty-three (7.7%) patients had ultrasounds requiring intervention within 14 days of imaging. Of these, eight (34.8%) had appendicitis, five (21.7%) had cholecystitis, four (17.4%) had urological pathology, three (13.0%) had gynecological pathology, and three (13.0%) had gastrointestinal diagnoses. Of note, 14 (60.9%) patients requiring follow-up or intervention within 14 days had symptoms that improved or resolved at the time of the outpatient ultrasound. For the 277 (92.6%) patients not requiring intervention, 117 (42.2%) had improved, 89 (32.1%) were unchanged, 50 (18.1%) had resolved, and 5 (1.8%) had worsened symptoms at the time of the follow-up ultrasound. Of the non-intervention patients, 13 (4.7%) went on to have alternative imaging, including magnetic resonance imaging, computed tomography, and a sonohysterogram.

CONCLUSIONS

Next-day ultrasound imaging remains a good way of identifying patients with serious pathology not appreciated at the time of their ED visit.

Retrospective review of abdominal aortic aneurysm deaths in New Zealand: what proportion of deaths is potentially preventable by a screening programme in the contemporary setting?

OBJECTIVES

To describe the proportions of people dying from abdominal aortic aneurysm (AAA) who might have benefited from a formal screening programme for AAA.

DESIGN

Retrospective cross-sectional review of deaths.

SETTING AND STUDY POPULATIONS

All AAA deaths registered in New Zealand from 2010 to 2014 in the absence of a national AAA screening programme.

MAIN OUTCOME MEASURES

Known history of AAA prior to the acute event leading to AAA death, prognosis limiting comorbidities, history of prior abdominal imaging and a validated multimorbidity measure (M3-index scores).

RESULTS

1094 AAA deaths were registered in the 5 years between 2010 and 2014 in New Zealand. Prior to the acute AAA event resulting in death, 31.3% of the cohort had a known AAA diagnosis, and 10.9% had a previous AAA procedure. On average, the AAA diagnosis was known 3.7 years prior to death. At least 77% of the people dying from AAA also had one or more other prognosis limiting diagnosis. The hazard of 1-year mortality associated with the non-AAA related comorbidities for the AAA cohort aged 65 or above were 1.5-2.6 times higher than to the age matched general population based on M3-index scores. In 2014, overall AAA deaths accounted for only 0.7% of total deaths, and 1.0% of deaths among men aged 65 or above in New Zealand. At most, 20% of people dying from AAA in New Zealand between 2010 and 2014 might have had the potential to derive full benefit from a screening programme. About 51% of cases would have derived no or very limited benefit from a screening programme.

CONCLUSION

Falling AAA mortality, and high prevalence of competing comorbidities and/or prior AAA diagnosis and procedure raises the question about the likely value of a national AAA screening programme in a country such as New Zealand.

Appropriateness of adult plain abdominal radiograph requesting in a regional Emergency Department

INTRODUCTION

Although commonly ordered, abdominal x-rays are thought to be overused and unhelpful in many emergency department patients. Our objectives were to evaluate the appropriateness of plain abdominal X-ray (AXR) requests in adult patients presenting to a Victorian regional emergency department (ED).

METHODS

A retrospective chart review was performed of all adult patients with a plain AXR requested by ED medical staff members in a regional healthcare centre in Victoria, Australia in 2016. Patient demographics, ED disposition and any further imaging results were extracted from the medical record. Indications for X-ray and clinician seniority were determined from the radiology request slips signed by the treating emergency doctor. Appropriateness of imaging was determined by comparing the indication for abdominal radiograph to local evidence-based guidelines.

RESULTS

One hundred and nine episodes of plain AXR requests met the inclusion criteria. Of these, 40 were considered inappropriate according to clinical guidelines. Overall, 36% (39/109) had normal or non-specific findings and 42% (46/109) demonstrated faecal loading, while 22% (24/109) identified pathology. Thirty-three patients had further imaging, mostly with computed tomography (CT). Junior staff members were responsible for most of the AXR requests.

CONCLUSION

In our regional hospital ED, over one third of AXRs requested for adult patients were inappropriate according to clinical guidelines. AXRs have a low diagnostic yield and frequently do not reduce the need for further imaging. The use of a clinical practice guideline and education of junior medical staff may increase the appropriate use of plain AXRs in the regional ED setting.

Epidemiologic trends in neuroendocrine tumors: An examination of incidence rates and survival of specific patient subgroups over the past 20 years

INTRODUCTION

Neuroendocrine tumors (NETs) represent a small proportion of cancers, but are increasing in incidence due to incidental diagnosis. We examined NET incidence and survival over time in a population-based registry.

MATERIALS/METHODS

We identified all NET cases diagnosed between 1995 and 2014 in the Surveillance, Epidemiology, and End Results database, November 2016 submission. We determined incidence rates and calculated overall and cancer-specific survival curves in different subgroups stratified by grade, stage, and age at diagnosis.

RESULTS

We identified 85,133 patients with a diagnosis of NET between 1995 and 2014. Patients with grade 1, localized NETs had the best median overall survival (233 months, 95% confidence intervals [CI] not estimable) and 5-year cancer-specific survival (97.6%; 95% CI, 97.4%, 97.8%). The median overall survival decreased with age across the entire spectrum of ages, with patients >70 years having a particularly poor prognosis (28.0 months; 95% CI, 26.5, 29.5). Patients >70 years old often had distant (34.3%) or grade 3 disease (40.8%), but even elderly patients with lower grade and/or stage disease had worse median overall survival compared with younger subjects.

CONCLUSIONS

Age appears to be associated with a worse prognosis independent of NET stage, and grade at the time of diagnosis. Patients with grade 1, localized NETs have an excellent long-term prognosis. Further research is warranted on reducing intensity of surveillance in these patients.

Early Abdominal Imaging Remains Over-Utilized in Acute Pancreatitis

BACKGROUND

Early abdominal computed tomography (CT) or magnetic resonance (MR) imaging is common in acute pancreatitis (AP). Guidelines (2007-2013) indicate routine use is unwarranted.

AIMS

To compare the frequency and evaluate the predictors of early CT/MR utilization for AP between September 2006-2007 (period A) and September 2014-2015 (period B).

METHODS

AP patients presenting directly to a large academic emergency department were prospectively enrolled during each period. Cases requiring imaging to fulfill diagnostic criteria were excluded. Early CT/MR (within 24 h of presentation) utilization rates were compared using Fisher's exact test. Predictors of early imaging usage were assessed with multivariate logistic regression.

RESULTS

The cohort included 96 AP cases in period A and 97 in period B. There were no significant differences in patient demographics, comorbidity scores, or AP severity. Period B cases manifested decreased rates of the systemic inflammatory response syndrome (SIRS) during the first 24 h of hospitalization (67% period A vs. 43% period B, p = 0.001). Independent predictors of early imaging included age >60 and SIRS or organ failure on day 1. No significant decrease in early CT/MR usage was observed from period A to B on both univariate (49% period A vs. 40% period B, p = 0.25) and multivariate (OR 1.0 for period B vs. A, 95% CI 0.5-1.9) analysis.

CONCLUSIONS

In a comparison of imaging practices for AP, there was no significant decrease in early abdominal CT/MR utilization from 2007 to 2015. Quality improvement initiatives specifically targeting early imaging overuse are needed.

Subsequent health-care utilization associated with early physical therapy for new episodes of low back pain in older adults

BACKGROUND

The association between early physical therapy (PT) and subsequent health-care utilization following a new visit for low back pain is not clear, particularly in the setting of acute low back pain.

PURPOSE

This study aimed to estimate the association between initiating early PT following a new visit for an episode of low back pain and subsequent back pain-specific health-care utilization in older adults.

DESIGN/SETTING

This is a prospective cohort study. Data were collected at three integrated health-care systems in the United States through the Back Pain Outcomes using Longitudinal Data (BOLD) registry.

PATIENT SAMPLE

We recruited 4,723 adults, aged 65 and older, presenting to a primary care setting with a new episode of low back pain.

OUTCOME MEASURES

Primary outcome was total back pain-specific relative value units (RVUs), from days 29 to 365. Secondary outcomes included overall RVUs for all health care and use of specific health-care services including imaging (x-ray and magnetic resonance imaging [MRI] or computed tomography [CT]), emergency department visits, physician visits, PT, spinal injections, spinal surgeries, and opioid use.

METHODS

We compared patients who had early PT (initiated within 28 days of the index visit) with those not initiating early PT using appropriate, generalized linear models to adjust for potential confounding variables.

RESULTS

Adjusted analysis found no statistically significant difference in total spine RVUs between the two groups (ratio of means 1.19, 95% CI of 0.72-1.96, p=.49). For secondary outcomes, only the difference between total spine imaging RVUs and total PT RVUs was statistically significant. The early PT group had greater PT RVUs; the ratio of means was 2.56 (95% CI of 2.17-3.03, p<.001). The early PT group had greater imaging RVUs; the ratio of means was 1.37 (95% CI of 1.09-1.71, p=.01.) CONCLUSIONS: We found that in a group of older adults presenting for a new episode of low back pain, the use of early PT is not associated with any statistically significant difference in subsequent back pain-specific health-care utilization compared with patients not receiving early PT.

Meeting the Needs for Radiation Protection: Diagnostic Imaging

Radiation and potential risk during medical imaging is one of the foremost issues for the imaging community. Because of this, there are growing demands for accountability, including appropriate use of ionizing radiation in diagnostic and image-guided procedures. Factors contributing to this include increasing use of medical imaging; increased scrutiny (from awareness to alarm) by patients/caregivers and the public over radiation risk; and mounting calls for accountability from regulatory, accrediting, healthcare coverage (e.g., Centers for Medicare and Medicaid Services), and advisory agencies and organizations as well as industry (e.g., NEMA XR-29, Standard Attributes on CT Equipment Related to Dose Optimization and Management). Current challenges include debates over uncertainty with risks with low-level radiation; lack of fully developed and targeted products for diagnostic imaging and radiation dose monitoring; lack of resources for and clarity surrounding dose monitoring programs; inconsistencies across and between practices for design, implementation and audit of dose monitoring programs; lack of interdisciplinary programs for radiation protection of patients; potential shortages in personnel for these and other consensus efforts; and training concerns as well as inconsistencies for competencies throughout medical providers' careers for radiation protection of patients. Medical care providers are currently in a purgatory between quality- and value-based imaging paradigms, a state that has yet to mature to reward this move to quality-based performance. There are also deficits in radiation expertise personnel in medicine. For example, health physics academic programs and graduates have recently declined, and medical physics residency openings are currently at a third of the number of graduates. However, leveraging solutions to the medical needs will require money and resources, beyond personnel alone. Energy and capital will need to be directed to:• innovative and cooperative cross-disciplinary institutional/practice oversight of and guidance for the use of diagnostic imaging (e.g., radiology, surgical specialties, cardiologists, and intensivists);• initiatives providing practical benchmarks (e.g., dose index registries);• comprehensive (consisting of access, integrity, metrology, analytics, informatics) and effective and efficient dose monitoring programs;• collaboration with industry;• improved use of imaging, such as through decision support combined with evidence-based appropriateness for imaging use;• integration with e-health such as medical records;• education, including information extending beyond the medical imaging community that is relevant to patients, public, and providers and administration;• identification of opportunities for alignment with salient media and advocacy organizations to deliver balanced information regarding medical radiation and risk;• open lines of communication between medical radiation experts and appropriate bodies such as the U.S. Environmental Protection Agency, the U.S. Food and Drug Administration, and the Joint Commission to assure appropriate guidance on documents and actions originating from these organizations; and• increased grant funding to foster translational work that advances understanding of low-level radiation and biological effects.

Associations Between Relative Value Units and Patient-Reported Back Pain and Disability

Objective: To describe associations between health care utilization measures and patient-reported outcomes (PROs). Method: Primary data were collected from patients ≥65 years with low back pain visits from 2011 to 2013. Six PROs of pain and functionality were collected 12 and 24 months after the index visits and total and spine-specific relative value units (RVUs) from electronic health records were tabulated over 1 year. We calculated correlation coefficients between RVUs and 12- and 24-month PROs and conducted linear regressions with each 12- and 24-month PRO as the outcome variables and RVUs as predictors of interest. Results: We observed very weak correlations between worse PROs at 12 and 24 months and greater 12-month utilization. In regression analyses, we observed slight associations between greater utilization and worse 12- and 24-month PROs. Discussion: We found that 12-month health care utilization is not strongly associated with PROs at 12 or 24 months.

A Systematic Review and Meta-Analysis of Diagnostic Performance of MRI for Evaluation of Acute Appendicitis

OBJECTIVE

A meta-analysis was performed to determine the accuracy of MRI in the diagnosis of acute appendicitis in the general population and in subsets of pregnant patients and children.

MATERIALS AND METHODS

A systematic search of the PubMed and EMBASE databases for articles published through the end of October 2014 was performed to identify studies that used MRI to evaluate patients suspected of having acute appendicitis. Pooled data for sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

A total of 30 studies that comprised 2665 patients were reviewed. The sensitivity and specificity of MRI for the diagnosis of acute appendicitis are 96% (95% CI, 95-97%) and 96% (95% CI, 95-97%), respectively. In a subgroup of studies that focused solely on pregnant patients, the sensitivity and specificity of MRI were 94% (95% CI, 87-98%) and 97% (95% CI, 96-98%), respectively, whereas in studies that focused on children, sensitivity and specificity were found to be 96% (95% CI, 95-97%) and 96% (95% CI, 94-98%), respectively.

CONCLUSION

MRI has a high accuracy for the diagnosis of acute appendicitis, for a wide range of patients, and may be acceptable for use as a first-line diagnostic test.

Radiology order decision support: examination-indication appropriateness assessed using 2 electronic systems

PURPOSE

The goal of the study was to determine the effects of guideline implementation strategy using 2 commercial radiology clinical decision support (CDS) systems.

METHODS

The appropriateness and insurance dispositions of MRI and CT orders were evaluated using the Medicalis SmartReq and Nuance RadPort CDS systems during 2 different 3-month periods. Logistic regression was used to compare these outcomes between the 2 systems, after adjusting for patient-mix differences.

RESULTS

Approximately 2,000 consecutive outpatient MRI and CT orders were evaluated over 2 periods of 3 months each. Medicalis scored 60% of exams as "indeterminate" (insufficient information) or "not validated" (no guidelines). Excluding these cases, Nuance scored significantly more exams as appropriate than did Medicalis (80% versus 51%, P < .001) and predicted insurance outcome significantly more often (76% versus 58%, P < .001). Only when the Medicalis "indeterminate" and "not validated" categories were combined with the high- or moderate-utility categories did the 2 CDS systems have similar performance. Overall, 19% of examinations with low-utility ratings were reimbursed. Conversely, 0.8% of examinations with high- or moderate-utility ratings were denied reimbursement.

CONCLUSIONS

The chief difference between the 2 CDS systems, and the strongest influence on outcomes, was how exams without relevant guidelines or with insufficient information were handled. Nuance augmented published guidelines with clinical best practice; Medicalis requested additional information utilizing pop-up windows. Thus, guideline implementation choices contributed to decision making and outcomes. User interface, specifically, the number of screens and completeness of indication choices, controlled CDS interactions and, coupled with guidance implementation, influenced willingness to use the CDS system.

Trends in advanced computed tomography use for injured patients in United States emergency departments: 2007-2010

OBJECTIVES

Studies have documented increased advanced radiography use in U.S. emergency departments (EDs) for injured patients over the past decade. The authors explored trends in recent years (2007 through 2010) in advanced radiography use, specifically head computed tomography (CT) and nonhead CT scans.

METHODS

This was a retrospective analysis of ED visits conducted using data from the National Hospital Ambulatory Medical Care Survey (NHAMCS), a representative sample of the U.S. ED visits from 2007 through 2010. All patients designated by the NHAMCS as "related to injury" were included in analyses. CT use was examined by head and nonhead use. Trends, predictors of utilization, and diagnostic yield for head and nonhead CT scans in injured ED patients were analyzed using survey-weighted logistic regression. Diagnostic yield was defined as the proportion of injury-related visits where patients imaged with CT received International Classification of Diseases, 9th Revision (ICD-9), code diagnoses of a severe head or nonhead injury.

RESULTS

Among injured ED patients, head CT use increased from 9.6% in 2007 to 11.6%, a relative increase of 20.8% (p < 0.001), and nonhead CT from 5.5% to 7.3%, a relative increase of 47.3% (p < 0.001). Diagnostic yield for head CT was unchanged (4.9% in 2007 vs. 3.4% in 2010, p = 0.093), but fell for nonhead CT from 6.4% in 2007 to 3.3% in 2010 (p = 0.04.

CONCLUSIONS

Advanced radiography use has continued to increase since 2007 in injured patients, and diagnostic yield for nonhead CT has continued to fall. Head CT is more common than CTs of other body areas and may represent an opportunity for reduction given validated clinical decision rules.

Advanced imaging use in intensive care units has decreased, resulting in lower charges without negative effects on patient outcomes

PURPOSE

There has been both greater recognition and scrutiny of the increased use of advanced imaging. Our aim was to determine whether there has been a change over time in the use of computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US) modalities in the intensive care units (ICUs).

MATERIALS AND METHODS

A retrospective review of 75657 admissions to 20 ICUs was conducted. Results were analyzed with multivariate linear, negative binomial, and Poisson regressions. Primary outcomes were rates of use of CT, MRI, and US per 1000 ICU admissions every 6 months. Secondary outcomes were changes in radiology use associated with impacts on mortality, hospital length of stay (LOS), ICU LOS, and hospital charges.

RESULTS

The rate of imaging use decreased by 13.5% between 2007 and 2011 (incidence rate ratio [IRR], 0.982; P < .001). Most of this decrease was by CTs (21.0%; IRR, 0.973; P < .001). Use of MRI decreased by 6.0% (IRR, 0.991; P = .04), whereas US increased by 18.9% (IRR, 1.012; P < .001). The charges associated with imaging decreased by $74 per ICU admission, which would save an estimated $1.2 million in charges during 2011. Decreased imaging was not associated with changes in mortality, hospital, and ICU LOS.

CONCLUSION

Advanced imaging use decreased for 5 years in the ICUs, resulting in decreased charges without negative effects on patient outcomes.

Evaluation of radiation dose among patients admitted through a university hospital emergency department

This study was conducted to evaluate the impact of different patient presentations/characteristics on medical imaging and radiation exposure. We collected data on the estimated effective radiation dose (EED) of patients admitted through our University Hospital ER, and analyzed the relationships of patient gender, age, admitting diagnosis, and admission duration on EED. All (592) patients admitted through our ER (with imaging) during 1-week periods in May/November 2009 were included. To compare EEDs according to admission diagnosis, seven categories were created: Cardiopulmonary, Gastrointestinal, Genitourinary, Neurologic, Trauma, Infectious, and Other. EEDs of patients with various admission durations were also evaluated. Units for all EEDs are mSv. Median EED (MEED) for all patients was 4.5. Males (7.8, females = 2.5) and adults (6.1, pediatrics = 1.8) experienced higher MEEDs, but significance was lost after controlling for other variables. MEED increased with admission duration (0.1 for <24 h, 1.8 for 1-3 days and 92.0 for >2 months). Trauma patients experienced the highest MEED (18.3), while patients with gastrointestinal/genitourinary diagnoses experienced the second highest MEED (13.0 mSv for both). Pediatric/male patients experienced heightened radiation exposure, but these relationships were largely due to other variables (higher male frequency/severity of trauma, pediatric patients had shorter admissions and diagnoses requiring less radiologic workup). Patients admitted following trauma and for prolonged durations showed elevated radiation exposure even after adjustment for all other variables. The identification of these relationships may aid in the development and focusing of future radiation awareness/reduction efforts to persons involved in the evaluation and care of patients with these presentations and characteristics.

Assessing the performance of imaging health systems in five selected hospitals in Uganda

OBJECTIVES

The first objective of the study was to develop an index termed as the 'Imaging Coverage' (IC), for measuring the performance of the imaging health systems. This index together with the Hospital-Based Utilization (HBU) would then be calculated for five Ugandan hospitals. Second, was to relate the financial resources and existing health policy to the performance of the imaging systems.

MATERIALS AND METHODS

This was a cross-sectional survey employing the triangulation methodology, conducted in Mulago National Referral Hospital. The qualitative study used cluster sampling, in-depth interviews, focus group discussions, and self-administered questionnaires to explore the non-measurable aspects of the imaging systems' performances.

RESULTS

The IC developed and tested as an index for the imaging system's performance was 36%. General X-rays had the best IC followed by ultrasound. The Hospital-Based Utilization for the five selected hospitals was 186 per thousand and was the highest for general radiography followed by ultrasound.

CONCLUSION

The IC for the five selected hospitals was 36% and the HBU was 186 per thousand, reflecting low performance levels, largely attributable to inadequate funding. There were shortfalls in imaging requisitions and inefficiencies in the imaging systems, financing, and health policy. Although the proportion of inappropriate imaging was small, reducing this inappropriateness even further would lead to a significant total saving, which could be channeled into investigating more patients. Financial resources stood out as the major limitation in attaining the desired performance and there is a need to increase budget funding so as to improve the performance of the imaging health systems.