Evaluation of Radiation Exposure from Computed Tomography of the Head

In an effort to reduce radiation exposure from computed tomography (CT), practitioners and facilities need to monitor radiation exposure while delivering high-quality diagnostic exams. Computed tomography scanners have a range of pre-programmed protocols for different examination types, with set values for tube potential, tube current, and rotation time (American Association of Physicists in Medicine, 2007). One way to minimize a patient’s exposure to radiation from CT is the use of an automatic exposure control (AEC) device. Current research is focusing on these devices and their actual benefits to patients. To assess the effectiveness of such a device, analysis of radiation doses per CT exam must occur. Machine-specific dose-length product (DLP) and or CT dose index (CTDI) are the only indicators of specific dose levels. This project compares current levels of radiation exposure to patients undergoing CT scans of the head, versus the national levels as evaluated by the Nationwide Evaluation of X-ray Trends (NEXT) program. Key words: Computed tomography, radiation exposure, reducing radiation, monitoring radiation levels, automatic exposure control

Value of Health Information Sharing in Reducing Healthcare Waste: An analysis of duplicate testing across hospitals

Recent healthcare reform has focused on reducing excessive waste in the US healthcare system, with duplicate testing being one of the main culprits. We explore the factors associated with duplication of radiology tests when information sharing across healthcare providers is fragmented, and patients switch from one hospital to another. We hypothesize that patients’ switching behavior across hospitals is associated with a higher levels of duplicate testing, and argue that implementation of intra- and inter-hospital information sharing technologies will help to reduce duplicate tests. We utilize a panel data set consisting of 39,600 patient visits across outpatient clinics of 68 hospitals from 2005 to 2012. Our results indicate that hospital switching is associated with greater duplicate testing and usage of inter-hospital information systems is associated with lower duplication. Our results support the need for implementation of health information exchanges as a potential solution to reduce the incidence of duplicate tests

MACHINE LEARNING APPROACHES ALONG THE RADIOLOGY VALUE CHAIN – RETHINKING VALUE PROPOSITIONS

Radiology is experiencing an increased interest in machine learning with its ability to use a large amount of available data. However, it remains unclear how and to what extent machine learning will affect radiology businesses. Conducting a systematic literature review and expert interviews, we compile the opportunities and challenges of machine learning along the radiology value chain to discuss their implications for the radiology business. Machine learning can improve diagnostic quality by reducing human errors, accurately analysing large amounts of data, quantifying reports, and integrating data. Hence, it strengthens radiology businesses seeking product or service leadership. Machine learning fosters efficiency by automating accompanying activities such as generating study protocols or reports, avoiding duplicate work due to low image quality, and supporting radiologists. These efficiency improvements advance the operational excellence strategy. By providing personnel and proactive medical solutions beyond the radiology silo, machine learning supports a customer intimacy strategy. However, the opportunities face challenges that are technical (i.e., lack of data, weak labelling, and generalisation), legal (i.e., regulatory approval and privacy laws), and persuasive (i.e., radiologists’ resistance and patients’ distrust). Our findings shed light on the strategic positioning of radiology businesses, contributing to academic discourse and practical decision-making

Image Sharing Technologies and Reduction of Imaging Utilization: A Systematic Review and Meta-analysis

INTRODUCTION: Image sharing technologies may reduce unneeded imaging by improving provider access to imaging information. A systematic review and meta-analysis were conducted to summarize the impact of image sharing technologies on patient imaging utilization. METHODS: Quantitative evaluations of the effects of PACS, regional image exchange networks, interoperable electronic heath records, tools for importing physical media, and health information exchange systems on utilization were identified through a systematic review of the published and gray English-language literature (2004-2014). Outcomes, standard effect sizes (ESs), settings, technology, populations, and risk of bias were abstracted from each study. The impact of image sharing technologies was summarized with random-effects meta-analysis and meta-regression models. RESULTS: A total of 17 articles were included in the review, with a total of 42 different studies. Image sharing technology was associated with a significant decrease in repeat imaging (pooled effect size [ES] = -0.17; 95% confidence interval [CI] = [-0.25, -0.09]; P < .001). However, image sharing technology was associated with a significant increase in any imaging utilization (pooled ES = 0.20; 95% CI = [0.07, 0.32]; P = .002). For all outcomes combined, image sharing technology was not associated with utilization. Most studies were at risk for bias. CONCLUSIONS: Image sharing technology was associated with reductions in repeat and unnecessary imaging, in both the overall literature and the most-rigorous studies. Stronger evidence is needed to further explore the role of specific technologies and their potential impact on various modalities, patient populations, and settings

Focal Spot, Fall/Winter 1986

https://digitalcommons.wustl.edu/focal_spot_archives/1044/thumbnail.jp

Point of care creatinine testing in diagnostic imaging: A feasibility study within the outpatient computed tomography setting

Introduction: Although the risks associated with iodinated contrast administration are acknowledged to be very low, screening of kidney function prior to administration is still standard practice in many hospitals. This study has evaluated the feasibility of implementing a screening form in conjunction with point of care (PoC) creatinine testing as a method to manage the risks of post contrast acute kidney injury (PC-AKI) within the CT imaging pathway. Method: Over an eight-week period 300 adult outpatients attending a UK CT department for contrast-enhanced scans were approached. Participants completed a screening questionnaire for co-morbidities linked to kidney dysfunction and consented to have a PoC and laboratory creatinine tests. Comparison was made against with previous baseline blood tests obtained within the preceding 3 months, as required by the study site. Participants were also invited to attend for follow up PoC and laboratory bloods tests at 48–72 h. Results: 14 patients (4.7%) had a scan-day eGFR below 45mL/min/1.73m2, all identified through screening. The majority of patients (n=281/300; 93.7%) fell in the same risk category based on previous and scan-day blood results. Six PoC test failures were recorded on the scan day. The constant error between the Abbott i-STAT PoC scan-day measurements and the laboratory scan-day measurements was -3.71 (95% CI: -6.41 to -0.50). Five patients had an elevated creatinine (≥25% from baseline) post contrast administration, but no instances of PC-AKI (≥50% from baseline) were identified. Conclusion: PoC creatinine testing is a practical method of ensuring renal function and is feasible in the radiology environment

The future of laboratory medicine - A 2014 perspective.

Predicting the future is a difficult task. Not surprisingly, there are many examples and assumptions that have proved to be wrong. This review surveys the many predictions, beginning in 1887, about the future of laboratory medicine and its sub-specialties such as clinical chemistry and molecular pathology. It provides a commentary on the accuracy of the predictions and offers opinions on emerging technologies, economic factors and social developments that may play a role in shaping the future of laboratory medicine

A JAFROC study of nodule detection performance in CT images of a thorax acquired during PET/CT

Purpose Two types of CT images (modalities) are acquired in PET/CT: for attenuation correction (AC) and diagnosis. The purpose of the study was to compare nodule detection and localization performance between these two modalities. Methods CT images, using both modalities, of an anthropomorphic chest phantom containing zero or more simulated spherical nodules of 5, 8, 10 and 12 mm diameters and contrasts −800, −630 and 100 HU were acquired. An observer performance study using nine observers interpreting 45 normal (zero nodules) images and 47 abnormal images (1–3 nodules; average 1.26) was conducted using the free-response receiver operating characteristic (FROC) paradigm. Data were analysed using an R software package implemented jackknife alternative FROC (JAFROC) analysis. Both empirical areas under the equally weighted AFROC curve (wAFROC) and under the highest rating inferred ROC (HR-ROC) curve were used as figures of merit (FOM). To control the probability of Type I error test alpha was set at 0.05. Results Nodule detection as measured by either FOM was significantly better on the diagnostic quality images (2nd modality), irrespective of the method of analysis, [reader averaged inter-modality wAFROC FOM difference = −0.07 (−0.11,−0.04); reader averaged inter-modality HR-ROC FOM difference = −0.05 (−0.09, −0.01)]. Conclusion Nodule detection was statistically worse on images acquired for AC; suggesting that images acquired for AC should not be used to evaluate pulmonary pathology. Keywords PET/CT; Nodule detection; JAFRO

Duplicated Laboratory Tests : A Hospital Audit And Evaluation Of A Computerized Alert Intervention

Laboratory testing is necessary when it contributes to the overall clinical management of the patient. Redundant testing, however, is often unnecessary and expensive and contributes to overall reductions in healthcare system efficiency. The purpose of this study is two-fold. First, to evaluate the frequency of ordering duplicate laboratory tests in hospitalized patients and the costs associated with this practice. Second, it was designed to determine if the use of a computerized alert or prompt will reduce the total number of unnecessarily duplicated Acute Hepatitis Profile (AHP) laboratory tests. This two-phase study took place in an inpatient facility that was part of a large tertiary care hospital system in Florida. A retrospective descriptive design was used during Phase 1 was to evaluate six laboratory tests and the frequency of ordering duplicate laboratory tests in hospitalized patients and to determine the associated costs of this practice for a 12-month time period in 2010. A test was considered a duplicate or an unnecessarily repeated test if it followed a previous test of the same type during the patient’s length of stay in the hospital and one in which any change in their values likely would not be clinically significant. A quasi-experimental pre- and post-test design was used during phase 2 was to determine the proportion of duplication of the AHP test before and after the implementation of a computerized alert intervention implemented as part of a system quality improvement process on January 5th, 2011. Data were compared for two 3-month time periods, pre- and post-alert implementation. The AHP test was considered redundant if it followed a previous test of the same type within 15 days of the initial test being final and present in the medical record. In phase 1, including each of the six tests examined, there were a total amount of 53, 351 test ordered, with 10, 375 (19.4%) of these cancelled. Out of the total amount of result final tests iv (n = 42,976), including each of the six tests examined, 4.6-8.7% were redundant. Results of the proportion of duplication of the six selected tests are as follows: AHP 196/2514 (7.8%), Antinuclear Antibody (ANA) 120/2594 (4.6%), B12/Folate level 396/5874 (6.7%), Thyroid Stimulating Hormone (TSH) 1893/21595 (8.7%), Ferritin 384/5171 (7.4%), and Iron/Total iron binding capacity (TIBC) 316/5155 (6.1%). The overall associated yearly cost of redundant testing of these six selected tests was an estimated $419, 218. The largest proportion of redundant tests was the Thyroid Stimulating Hormone level, costing a yearly estimated$300, 987. In Phase 2, prior to introduction of the alert, 674 AHP tests were performed. Of these, 53 (7.9%) were redundant. During the intervention period, 692 AHP tests were performed, of these 18 (2.6%) were redundant. The implementation of the computerized alert was shown to significantly reduce the proportion of AHP tests (Chi-Square: χ2 = df 1, p ≤ 0.001). The differences in the associated costs of duplicated AHP were $5238 dollars in 2010 as compared to$1746 in 2011 post-alert and these differences were significant (Mann Whitney U, Z = -4.04, p ≤ 0.001). Although the proportions of unnecessarily repeated diagnostic tests that were observed during Phase 1 of this study were small, the associated costs could adversely affect hospital revenue and overall healthcare efficiency. The implementation of the AHP computerized alert demonstrated a drop in the proportion of redundant AHP tests and subsequent associated cost savings. It is necessary to perform further research to evaluate computerized alerts on other tests with evidence-based test-specific time intervals, and to determine if such reductions postimplementation of AHP alerts are sustained over time

Utilization and utility of diagnostic imaging : Quantitative studies and normative considerations

Today the practice of most medical disciplines is almost unrecognisable without modern radiology. Imaging technology is fascinating, is developing rapidly, and is without doubt beneficial, but there are also concerns about over-utilization, the risks of harm and the costs involved. The overall aim of this dissertation is to improve our understanding of utilization of radiological services, by investigating aspects of the actual use and as perceived by the radiologist. Further, the aim is to illuminate utility issues based on empirical research. The utilization of imaging was investigated through two quantitative surveys. We collected activity data from all radiology institutions in Norway in order to estimate the frequency of radiological examinations. A questionnaire was mailed to Norwegian radiologists to obtain information about their perceptions, actions and reasoning regarding utilization of imaging. We found a significant increase in utilization of diagnostic imaging, especially MRI and CT examinations, leading to a relatively high increase in the collective effective dose. We found that geographical variation in examination frequency was highest for these newer technologies. Accessibility is a likely explanation for both the increase in utilization over time and the geographical variation. According to the radiologists, the major causes of increasing utilization were related to ‘supply and demand’ mechanisms, like expanded technological and medical possibilities, availability of services, and the demands of people and referring clinicians for assurance. They consider over-utilization to comfort patients and clinicians to be the main cause of unnecessary examinations, followed by insufficient referral information. Almost all radiologists reported that they frequently took action in response to inadequate referrals, mainly by contacting the clinician and by checking the medical records. Such actions were primarily motivated by patient safety considerations (risk of complications, radiation dose and low patient age), while somewhat hindered by respect for the judgment of the referrer, the wishes of the patient and practical obstacles. The empirical findings indicate benefits of increasing utilization of imaging in the shape of improved health outcome, reduced pain and lower costs, but also lack of such benefits and possible harm. The overall usefulness of increased utilization can be considered to be limited from a utilitarian perspective. Norms and measures to manage utilization of imaging initiated by the professionals are those that should have the highest potential for increasing the utility of services. Key elements of such measures should be clinical guidelines, giving radiologists more discretionary power, and critical assessment of referrals