Inpatient imaging utilization: trends of the past decade

What is the appropriate measure of radiology workload: Study or image numbers?

INTRODUCTION

Previous studies assessing the volume of radiological studies rarely considered the corresponding number of images. We aimed to quantify the increases in study and image numbers per radiologist in a tertiary healthcare network to better understand the demands on imaging services.

METHODS

Using the Picture Archiving and Communication System (PACS), the number of images per study was obtained for all diagnostic studies reported by in-house radiologists at a tertiary healthcare network in Melbourne, Australia, between January 2009 and December 2022. Payroll data was used to obtain the numbers of full-time equivalent radiologists.

RESULTS

Across all modalities, there were 4,462,702 diagnostic studies and 1,116,311,209 images. The number of monthly studies increased from 17,235 to 35,152 (104%) over the study period. The number of monthly images increased from 1,120,832 to 13,353,056 (1091%), with computed tomography (CT) showing the greatest absolute increase of 9,395,653 images per month (1476%). There was no increase in the monthly studies per full-time equivalent radiologist; however, the number of monthly image slices per radiologist increased 399%, from 48,781 to 243,518 (Kendall Tau correlation coefficient 0.830, P-value < 0.0001).

CONCLUSION

The number of monthly images per radiologist increased substantially from 2009 to 2022, despite a relatively constant number of monthly studies per radiologist. Our study suggests that using the number of studies as an isolated fundamental data set underestimates the true radiologist's workload. We propose that the increased volume of images examined by individual radiologists may more appropriately reflect true work demand and may add more weight to future workforce planning.

Economic and Environmental Costs of Cloud Technologies for Medical Imaging and Radiology Artificial Intelligence

Radiology is on the verge of a technological revolution driven by artificial intelligence (including large language models), which requires robust computing and storage capabilities, often beyond the capacity of current non-cloud-based informatics systems. The cloud presents a potential solution for radiology, and we should weigh its economic and environmental implications. Recently, cloud technologies have become a cost-effective strategy by providing necessary infrastructure while reducing expenditures associated with hardware ownership, maintenance, and upgrades. Simultaneously, given the optimized energy consumption in modern cloud data centers, this transition is expected to reduce the environmental footprint of radiologic operations. The path to cloud integration comes with its own challenges, and radiology informatics leaders must consider elements such as cloud architectural choices, pricing, data security, uptime service agreements, user training and support, and broader interoperability. With the increasing importance of data-driven tools in radiology, understanding and navigating the cloud landscape will be essential for the future of radiology and its various stakeholders.

Neuroimaging of Headache: Indications and Controversies

Headache is a common presenting symptom in the ambulatory setting that often prompts imaging. The increased use and associated health care money spent in the setting of headache have raised questions about the cost-effectiveness of neuroimaging in this setting. Neuroimaging for headache in most cases is unlikely to reveal significant abnormality or impact patient management. In this article, reasons behind an observed increase in neuroimaging and its impact on health care expenditures are discussed. The typical imaging modalities available and various imaging guidelines for common clinical headache scenarios are presented, including recommendations from the American College of Radiology.

Magnetic resonance imaging (MRI) utilization in a Ghanaian teaching hospital: trend and policy implications

Background

The use of Magnetic Resonance Imaging (MRI) is new in Ghana compared with some Western countries. A number of studies have observed increased MRI utilization due to increased sensitivity to diagnosis, and the paradigm shift to modalities that do not use radiation. Challenges with MRI use include high cost of the examination and inappropriate requests by referring clinicians.

Objective

To determine the MRI utilisation trend in Korle Bu Teaching Hospital (KBTH), Ghana and its policy implications.

Materials and Methods

A retrospective study undertaken in the Radiology Department, KBTH, from February to March, 2017. Eight hundred and forty request forms for MRI studies between January, 2013 and December 2016 were reviewed. Information on patient's age and sex, number of MRI studies done, body parts and clinical conditions evaluated, appropriateness of clinical requests and existing policies on MRI in Ghana was gathered. Measures of central tendency and spread were obtained. Chi square, Pearson's correlation and linear regression analysis were also used in the analysis.

Results

The top three body parts requested were Spine (55 %), Brain (19%) and Joints (6 %); degenerative disease was the most common clinical condition evaluated.

Significant association and correlation were obtained between of the number of body parts evaluated and examination year as well as the variety of clinical conditions requested and examination year.

Conclusion

A progressive increase was noted in MRI utilisation both in number and diversity but no policy guiding MRI use in Ghana exists.

Funding

None declared

Incidence and Survival in Reproductive-Aged Women with Differentiated Thyroid Cancer: United States SEER 18 2000-2016

Background: Incidence of differentiated thyroid cancer has increased in the United States and globally with disproportionate increases observed among women. Recent data suggest that factors other than increased detection may underlie this increase. To understand incidence and survival patterns in differentiated thyroid cancer during a time period of increasing imaging, we examined data from a contemporary population-based sample of U.S. reproductive-aged women. Methods: Women aged 20-49 years (N = 61,552) diagnosed with papillary thyroid cancer (PTC) or follicular thyroid cancer (FTC) during 2000-2016 were identified from the U.S. National Cancer Institute Surveillance, Epidemiology, and End Results 18 registries database. For each age decade (20-29, 30-39, 40-49 years), we estimated age-adjusted average annual percentage changes in incidence using segmented and unsegmented regression models and 15-year survival. Results were stratified by race/ethnicity and cancer stage. Results: The estimated incidence of PTC increased during 2000-2016 among women aged 20-29 years and during 2000-2012 among women aged 30-49 years. During 2012-2016, incidence stabilized among women aged 30-39 years and decreased among women aged 40-49 years. For FTC, incidence decreased slightly among women aged 20-29 years and was rather stable among those aged 30-49 years during 2000-2016, although increases were observed among non-Hispanic black women aged 30-49 years. By stage, the percentage increase in PTC incidence was largest for regional disease. Fifteen-year estimated survival was generally high but somewhat lower among women aged 40-49 years than those aged 20-39 years. Survival was similar for PTC and FTC except among women aged 20-29 years, for whom survival was modestly lower with FTC than PTC. Conclusions: Our findings confirm increasing incidence of PTC among U.S. women aged 20-29 years, a recent stabilization of PTC incidence in women 30-49 years, and stable to decreasing incidence of FTC. Increased detection based on imaging is unlikely to fully explain the continued increase in PTC incidence, given the increasing incidence of regional disease and routine imaging occurring less often among premenopausal than postmenopausal women. Although survival is generally high, treatment often requires surgery and lifelong medications. Further investigations into contributors to these trends are warranted to reduce future morbidity in reproductive-aged women.

Trends in Publicly Reported Quality Measures of Hospital Imaging Efficiency, 2011-2018

OBJECTIVE. In 2011, the Centers for Medicare & Medicaid Services (CMS) initiated public reporting of outpatient imaging efficiency measures to reduce potentially inappropriate imaging and unnecessary exposure to ionizing radiation performed in hospital outpatient departments. Three CMS quality measures were designed to reduce duplicative CT in the Medicare population: OP-10, which CMS lists as "Abdomen Computed Tomography-Use of Contrast Material"; OP-11, which CMS lists as "Thorax CT-Use of Contrast Material"; and OP-14, which CMS lists as "Simultaneous Use of Brain CT and Sinus CT." We describe trends in hospital performance on these national hospital outpatient imaging efficiency measures since the inception of their public reporting. MATERIALS AND METHODS. This observational analysis used standard Medicare fee-for-service administrative claims to calculate hospital-specific scores for OP-10, OP-11, and OP-14. Consistent with CMS specifications, each measure was calculated as a percentage with appropriate exclusions and minimum case count requirements to ensure measure score validity and reliability. We report national performance as well as distributions of hospital performance scores for each annual public reporting period. Trend analyses were performed to examine changes in annual mean performance over time. Secondary analyses assessed trends and hospital performance by location (rural vs urban) and hospital characteristics. RESULTS. Between 2011 and 2018, the national mean rate of duplicate imaging declined for all three measures (OP-10, 18.9% vs 7.7%; OP-11, 5.6% vs 2.0%; OP-14, 2.5% vs 1.0%). For OP-10 and OP-11, most outlier hospitals were rural, small, and government-owned. For OP-10, rural facilities accounted for 32.2% of all facilities but 46.0% of outliers by the end of the study period. Similarly, for OP-11, rural facilities accounted for 30.1% of all facilities but 47.0% of outliers by the end of the study period. In general, the proportion of outliers located in rural areas decreased over time. CONCLUSION. National performance on CMS quality measures of duplicative CT has improved over time, with reduced variation observed between hospitals since the inception of public reporting. These successes support recent CMS policy initiatives to retire duplicative imaging measures from public reporting. Future work should seek to identify opportunities to use national public reporting initiatives to yield similar improvements across broader indications and settings.

Appropriateness Criteria for Neuroimaging of Adult Headache Patients in the Emergency Department: How Are We Doing?

The American College of Radiology (ACR) developed Appropriateness Criteria (ACR-AC) for diagnostic imaging to reduce overuse and promote high-yield, cost-effective, evidence-based decision-making. For adult headaches, there are 16 variants with specific imaging recommendations. Headache accounts for 4.5% of emergency department (ED) visits, and 61% are chronic. Imaging for headaches has increased in the past 2 decades, with intracranial pathology diagnoses going down. Evidence suggests that there is poor knowledge of the ACR-AC among advanced practice nurses (APNs) and nonradiologist physicians. The ACR-AC recommendations were examined using the Health Care Cost and Utilization Project State Emergency Department Data (HCUP SEDD) from Maryland in 2013. Imaging proportions were examined, as well as differences between residency program hospitals and hospitals that have APNs in the ED. Of the 11,109 chronic headache visits, a quarter underwent computed tomography ([CT]; 26.9%) and 3.6% underwent magnetic resonance imaging (MRI); the ACR-AC does not recommend use of either of these in patients with chronic headache. There were significant practice differences related to hospital teaching and whether APNs were employed in the ED or not. For patients with posttraumatic headache, there were no significant differences in practice. Computed tomography was used in 76.4% of posttraumatic headache visits. It is unknown whether the ACR-AC are being used in the ED, and there is variability in following the recommendations. Posttraumatic headache protocol is well established in the ED, but chronic headache continues to be a problem in imaging overuse despite recommendations. Radiological education, including the ACR-AC, as well as radiation dosing and exposure information should be part of APN, physician, and registered nurse education, as well as continuing education. Continuing education is critical for adherence to the ACR-AC, as the recommendations are complex and continuously evolving. In addition, to minimize overuse of CT in headaches, the ACR-AC should be integrated into clinical decision support to promote best imaging practices.

Utilization Trends in Diagnostic Imaging for a Commercially Insured Population: A Study of Massachusetts Residents 2009 to 2013

PURPOSE

To report utilization trends in diagnostic imaging among commercially insured Massachusetts residents from 2009 to 2013.

MATERIALS AND METHODS

Current Procedural Terminology codes were used to identify diagnostic imaging claims in the Massachusetts All-Payer Claims Database for the years 2009 to 2013. We reported utilization and spending annually by imaging modality using total claims, claims per 1,000 individuals, total expenditures, and average per claim payments.

RESULTS

The number of diagnostic imaging claims per insured MA resident increased only 0.6% from 2009 to 2013, whereas nonradiology claims increased by 6% annually. Overall diagnostic imaging expenditures, adjusted for inflation, were 27% lower in 2009 than 2013, compared with an 18% increase in nonimaging expenditures. Average payments per claim were lower in 2013 than 2009 for all modalities except nuclear medicine. Imaging procedure claims per 1,000 MA residents increased from 2009 to 2013 by 13% in MRI, from 147 to 166; by 17% in ultrasound, from 453 to 530; and by 12% in radiography (x-ray), from 985 to 1,100. However, CT claims per 1,000 fell by 37%, from 341 to 213, and nuclear medicine declined 57%, from 89 claims per 1,000 to 38.

CONCLUSION

Diagnostic imaging utilization exhibited negligible growth over the study period. Diagnostic imaging expenditures declined, largely the result of falling payments per claim in most imaging modalities, in contrast with increased utilization and spending on nonimaging services. Utilization of MRI, ultrasound, and x-ray increased from 2009 to 2013, whereas CT and nuclear medicine use decreased sharply, although CT was heavily impacted by billing code changes.

Access to primary care and computed tomography use in the emergency department

Background

The decision to obtain a computed tomography CT scan in the emergency department (ED) is complex, including a consideration of the risk posed by the test itself weighed against the importance of obtaining the result. In patients with limited access to primary care follow up the consequences of not making a diagnosis may be greater than for patients with ready access to primary care, impacting diagnostic reasoning. We set out to determine if there is an association between CT utilization in the ED and patient access to primary care.

Methods

We performed a cross-sectional study of all ED visits in which a CT scan was obtained between 2003 and 2012 at an academic, tertiary-care center. Data were abstracted from the electronic medical record and administrative databases and included type of CT obtained, demographics, comorbidities, and access to a local primary care provider (PCP). CT utilization rates were determined per 1000 patients.

Results

A total of 595,895 ED visits, including 98,001 visits in which a CT was obtained (16.4%) were included. Patients with an assigned PCP accounted for 55% of all visits. Overall, CT use per 1000 ED visits increased from 142.0 in 2003 to 169.2 in 2012 (p < 0.001), while the number of annual ED visits remained stable. CT use per 1000 ED visits increased from 169.4 to 205.8 over the 10-year period for patients without a PCP and from 118.9 to 142.0 for patients with a PCP. Patients without a PCP were more likely to have a CT performed compared to those with a PCP (OR 1.57, 95%CI 1.54 to 1.58; p < 0.001). After adjusting for age, gender, year of visit and number of comorbidities, patients without a PCP were more likely to have a CT performed (OR 1.20, 95% CI 1.18 to 1.21, p < 0.001).

Conclusions

The overall rate of CT utilization in the ED increased over the past 10 years. CT utilization was significantly higher among patients without a PCP. Increased availability of primary care, particularly for follow-up from the ED, could reduce CT utilization and therefore decrease costs, ED lengths of stay, and radiation exposure.

Prospective study of a non-restrictive decision rule for acute aortic syndrome

OBJECTIVES

To determine the impact of a non-restrictive clinical decision rule on CT utilization for Emergency Department patients suspected of having an acute aortic syndrome (AAS).

METHODS

We prospectively assessed the performance of a previously described, collaboratively designed, non-restrictive clinical decision rule for AAS. Emergency Department patients with suspected AAS were stratified into low and high-risk groups based on decision rule results, from July 2013-August 2014. Patients with acute trauma, prior AAS or aortic surgery were excluded. CT dose reduction protocols were concurrently implemented as a quality improvement measure. Bivariate analysis was performed to compare the prospective cohort with the historical derivation cohort for CT utilization rates, results of CT, AAS incidence and radiation exposure. The performance of the clinical decision rule was evaluated.

RESULTS

Compared with the historic cohort, the study cohort demonstrated a lower CT utilization rate [0.344% (427/124,093) versus 0.477% (1465/306,961), (p<0.001)], a trend toward higher CT diagnostic yield [4.4% (19/427) versus 2.7% (40/1465), (p=0.08)]. AAS incidence was similar [0.015% (19/124,093) versus 0.013% (40/306,961), (p=0.57)]. The mean effective radiation dose was markedly lower [12±5.5mSv versus 43±20mSv, (p<0.0001)]. The clinical decision rule correctly stratified only 56% (10/18) of patients with AAS as high-risk.

CONCLUSIONS

A non-restrictive, collaboratively designed, clinical decision rule for Emergency Department patients with suspected AAS performed poorly in risk-stratifying patients for AAS. However, its implementation was associated with a significant and safe decrease in CT utilization.

2005 to 2014 CT and MRI Utilization Trends in the Context of a Nondenial Prior Authorization Program

Purpose:

Reducing unnecessary testing may benefit patients, as some computed tomography (CT) and magnetic resonance imaging (MRI) expose patients to contrast, and all CTs expose patients to radiation. This observational study with historical controls assessed shifts in CT and MRI utilization over a 9-year period after a private health insurer’s implementation of a nondenial, consultative prior authorization program.

Methods/Materials:

Normalized rates of exams per 1000 person-years were plotted over 2005 to 2014 for people with commercial and Medicare Advantage health plans in the San Antonio market, with 2005 utilization set as the baseline. The program was implemented at the start of 2006. Computed tomography and MRI utilization changes were compared with contemporaneous changes in low-tech plain film and ultrasound utilization.

Results:

Growth in high-tech imaging utilization decelerated or reversed during the period. In 2006, CT utilization dropped to between 76% and 90% of what it had been in 2005, depending on the plan. In 2014, it was between 52% and 88% of its initial level. MRI utilization declined to between 86% and 94% of its initial level in 2006, and then to between 50% and 75% in 2014. Ultrasound utilization was greater in 2014 than in 2005 for some plans. Plain film utilization declined between 2005 and 2014 for all plans.

Conclusion:

There was an immediate and sustained decline in CT and MRI utilization after the introduction of the program. While many factors may have impacted the long-term trends, the mixed trends in low-tech imaging suggest that a decline in low-tech imaging was not responsible for the decline in CT and MRI utilization.

Significant but reasonable radiation exposure from computed tomography-related medical imaging in the ICU

Admission to an intensive care unit (ICU) is associated with increased medical imaging and radiation exposure, yet few studies have estimated the risk of cancer associated with these examinations. The purpose of this study was to review computed tomography (CT) scans performed on patients admitted to two urban academic ICUs, predict their radiation exposure, and calculate their estimated lifetime attributable risk of cancer (LAR). An electronic chart review was performed on all CT scans performed between January 2007 and December 2011. The estimated effective dose of radiation was calculated for each CT, and the LAR for each patient was predicted. Mean radiation exposure was 22.2 ± 25.0 mSv with a mean LAR of 0.1 ± 0.2 % and a median of 0.6 % with a range of <0.001 to 3.4 %. Our cohort received radiation doses higher than recommended by guidelines; however, the critical nature of their admission may have warranted these imaging studies. Estimated risk of cancer in this population was overall low.

Rising utilization of CT in adult fall patients

OBJECTIVE. Falls are a common cause of emergency department (ED) visits in the United States. We evaluated trends in CT utilization for adult fall patients in the United States from 2001 to 2010. MATERIALS AND METHODS. Using the National Hospital Ambulatory Medical Care Survey, we identified all visits from 2001 to 2010 of adult patients presenting to EDs after falls. This database surveys approximately 500 EDs annually for 4 weeks, providing national estimates on ED resource utilization and outcomes. We studied trends in CT utilization and proportion of visits with life-threatening conditions (intracranial hemorrhage, organ laceration, axial skeletal fractures) after falls. We also studied the association between CT utilization rates and demographic characteristics and admission status. RESULTS. A total of 22,166 unweighted observations representing 73,241,368 visits were identified. The proportion of adult fall patient visits during which CT was performed increased from 11.4% in 2001 to 28.0% in 2010 (p < 0.0001), whereas the proportion of adult fall visits with life-threatening conditions increased from 5.7% to 8.2% (p < 0.0001). On adjusted analysis (adjusting for life-threatening condition and demographic variables), each successive year was independently associated with CT utilization (odds ratio, 1.21 [95% CI, 1.21-1.21]). The odds of CT utilization in 2010 compared with 2001 were 2.62 (95% CI, 2.61-2.62). CONCLUSION. There was a 2.5-fold increase in CT utilization among adult fall patient visits from 2001 to 2010. When demographic and clinical variables were controlled for, increasing year was independently associated with CT utilization. These findings suggest that CT may be overutilized among adult fall patients.

Effect of Evidence-based Clinical Decision Support on the Use and Yield of CT Pulmonary Angiographic Imaging in Hospitalized Patients

PURPOSE

To determine the effect of clinical decision support (CDS) on the use and yield of inpatient computed tomographic (CT) pulmonary angiography for acute pulmonary embolism (PE).

MATERIALS AND METHODS

This HIPAA-compliant, institutional review board-approved study with waiver of informed consent included all adults admitted to a 793-bed teaching hospital from April 1, 2007, to June 30, 2012. The CDS intervention, implemented after a baseline observation period, informed providers who placed an order for CT pulmonary angiographic imaging about the pretest probability of the study based on a validated decision rule. Use of CT pulmonary angiographic and admission data from administrative databases was obtained for this study. By using a validated natural language processing algorithm on radiology reports, each CT pulmonary angiographic examination was classified as positive or negative for acute PE. Primary outcome measure was monthly use of CT pulmonary angiography per 1000 admissions. Secondary outcome was CT pulmonary angiography yield (percentage of CT pulmonary angiographic examinations that were positive for acute PE). Linear trend analysis was used to assess for effect and trend differences in use and yield of CT pulmonary angiographic imaging before and after CDS.

RESULTS

In 272 374 admissions over the study period, 5287 patients underwent 5892 CT pulmonary angiographic examinations. A 12.3% decrease in monthly use of CT pulmonary angiography (26.0 to 22.8 CT pulmonary angiographic examinations per 1000 admissions before and after CDS, respectively; P = .008) observed 1 month after CDS implementation was sustained over the ensuing 32-month period. There was a nonsignificant 16.3% increase in monthly yield of CT pulmonary angiography or percentage of CT pulmonary angiographic examinations positive for acute PE after CDS (P = .65).

CONCLUSION

Implementation of evidence-based CDS for inpatients was associated with a 12.3% immediate and sustained decrease in use of CT pulmonary angiographic examinations in the evaluation of inpatients for acute PE. for this article.

Radiology utilization in the emergency department: trends of the past 2 decades

OBJECTIVE

The objective of our study was to assess radiology utilization trends for emergency department (ED) patients from 1993 through 2012.

MATERIALS AND METHODS

For this retrospective study, we reviewed radiology utilization at a 793-bed quaternary care academic medical center from January 1, 1993, through December 31, 2012, during which time the number of ED patient visits increased from approximately 48,000 to 61,000, and determined the number of imaging studies by modality (radiography, sonography, CT, MRI, other) and associated relative value units (RVUs). We used linear regression to assess for trends in the number of imaging RVUs and imaging accession numbers, our primary and secondary outcomes, respectively.

RESULTS

The total RVUs attributable to ED imaging per 1000 ED visits increased 208% from 1993 to 2007 (p < 0.0001) and then decreased 24.7% by 2012 (p = 0.0019). The total number of imaging accession numbers per 1000 ED visits increased 47.8% from 1993 until 2005 (p = 0.0003) and then decreased 26.9% by 2012 (p < 0.0001). CT RVUs per 1000 ED visits increased 493% until 2007 (p < 0.0001) and then decreased 33.4% (p < 0.0001), and MRI RVUs increased 2475% until 2008 (p < 0.0001) and then decreased 20.6% (p < 0.0032). Sonography RVUs increased 75.7% over the study period (p < 0.0001), whereas radiography RVUs decreased 28.1% (p = 0.0009).

CONCLUSION

After a period of substantial increase from 1993 to 2007, volume-adjusted ED imaging RVUs declined from 2007 through 2012, largely because of the decreasing use of CT and MRI. Additional studies are needed to determine the causes of this decline, which may include quality improvement activities, advocacy for appropriateness by leadership, concerns regarding radiation exposure and cost, and health information technology interventions.