Secondary Interpretation of CT Examinations: Frequency and Payment in the Medicare Fee-for-Service Population

PurposeSecondary interpretation of diagnostic imaging examinations (providing a second formal interpretation for imaging performed at another institution) may reduce repeat imaging after transfer of care. Recently, CMS requested information to guide payment policy. We aimed to study historic trends in submitted claims and payments for secondary interpretation services in the Medicare fee-for-service population.MethodsApplying current procedural terminology codes by body part to Medicare Part B aggregate claims files, we identified all CT interpretation services rendered between 1999 and 2012. Secondary interpretation services were identified using combined code modifiers 26 and 77, in accordance with CMS billing guidelines. The frequencies of billed and denied services were extracted for primary and secondary CT interpretation services. Primary versus secondary interpretation denial rates were calculated and compared.ResultsOf all 227 million Medicare Part B claims for CT services, 299,468 (0.13%) were for secondary interpretation services. From 1999 to 2012, growth in secondary interpretation claims outpaced that in primary interpretation claims (+811% versus +56%; compound annual growth rate 17% versus 3.2%). As a percentage of all services, secondary interpretations increased from 0.05% in 1999 to 0.30% in 2012. Denial rates for second interpretations decreased from 1999 to 2012 (12.7% to 7.0%), and now approach those for primary interpretations (5.4% in 2012).ConclusionsMedicare claims for secondary interpretation of CT examinations are growing but account for less than 1% of all billed CT interpretation services. Denial rates are similar to those of primary interpretation services.     

Professional Services Rendered by Nurse Practitioners and Physician Assistants Employed by Radiology Practices: Characteristics and Trends From 2017 Through 2019

PurposeWith radiology practices increasingly employing nonphysician practitioners (NPPs), we aimed to characterize specific NPP clinical roles.MethodsLinking 2017 to 2019 Medicare data sets, we identified all claims-submitting nurse practitioners and physician assistants (together NPPs) employed by radiologists. NPP-billed services were identified, weighted by work relative value units, and categorized as (1) clinical evaluation and management (E&M), (2) invasive procedures, and (3) noninvasive imaging interpretation. NPP practice patterns were assessed temporally and using frequency analysis.ResultsAs the number of radiologist-employed NPPs submitting claims increased 16.3% (from 523 in 2017 to 608 in 2019), their aggregate Medicare fee-for-service work relative value units increased 17.3% (+40.0% for E&M [from 79,540 to 111,337]; +5.6% for procedures [from 179,044 to 189,003]; and +74.0% for imaging [from 5,087 to 8,850]). The number performing E&M, invasive procedures, and imaging interpretation increased 7.6% (from 329 to 354), 18.3% (from 387 to 458), and 31.8% (from 85 to 112), with 58.2%, 75.3%, and 18.4% billing those services in 2019. Paracentesis and thoracentesis were the most frequently billed invasive procedures. Fluoroscopic swallowing and bone densitometry examinations were the most frequently billed imaging services. By region, NPPs practicing as majority clinical E&M providers were most common in the Midwest (33.5%) and South (33.0%), majority proceduralists in the South (53.1%), and majority image interpreters in the Midwest (50.0%).ConclusionsAs radiology practices employ more NPPs, radiologist-employed NPPs’ aggregate services have increased for E&M, invasive procedures, and imaging interpretation. Most radiologist-employed NPPs perform invasive procedures and E&M. Although performed by a small minority, imaging interpretation has shown the largest relative service growth.     

Invasive Procedural Versus Diagnostic Imaging and Clinical Services Rendered by Radiology Trainees Over Two Decades

PurposeTo characterize evolving radiology trainee exposure to invasive procedures.MethodsUsing Physician/Supplier Procedure Summary Master Files from 1997 to 2016, we identified Medicare services performed by radiology trainees in approved programs by extracting information on services billed by diagnostic and interventional radiologists reported with “GC” modifiers. Services were categorized as (1) invasive procedures, (2) noninvasive diagnostic imaging services, or (3) clinical evaluation and management (E&M) services. Relative category trainee work effort was estimated using service-level work relative value units.ResultsNationally from 1997 to 2016, invasive procedures declined from 34.2% to 14.3% of relative work effort for all Medicare-billed radiology trainee services. Radiology trainees’ noninvasive diagnostic imaging services increased from 65.1% to 85.4%. Clinical E&M services remained uniformly low (0.7%-0.3%). Diagnostic radiology (DR) and interventional radiology (IR) faculty supervised 81.0% and 19.0%, respectively, of all trainee invasive procedures in 1997, versus 68.3% and 31.7%, respectively, in 2016. Despite declining relative procedural work, trainees were exposed to a wide range of both basic and complex invasive procedures in both 1997 and 2016. Over this period, trainee noninvasive diagnostic imaging services shifted away from radiography to CT and MRI.ConclusionRadiology trainees’ relative invasive procedural work effort has declined over time as their work increasingly focuses on CT and MRI. As DR and IR-DR residency curricula begin to diverge, it is critical that both DR and IR residents receive robust training in basic image-guided procedures to ensure broad patient access to these services.     

Determining the Patient Complexity of Head CT Examinations: Implications for Proper Valuation of a Critical Imaging Service

PurposeThe head-computed tomography (CT) exam code was recently identified by policy makers as having a potentially overvalued resource value units (RVU). A critical aspect in determining RVUs is the complexity of patients undergoing the service. This study evaluated the complexity of patients undergoing head-CT.MethodsThe 2017 Medicare PSPS Master File was used to identify the most common site for performing head-CT examinations. Given the most common location, the 5% Research Identifiable File, was then used to evaluate complexity of patients undergoing head CT on the same day as an emergency department (ED) visit based on the Evaluation & Management (E&M) “level” of these visits (1-least complex to 5-most complex patient) and the ICD-10 diagnosis coding associated with the billed head CT claims.Results56.1% of head CT examinations were performed in the ED. Seventy percent of noncontrast exams performed in the ED were ordered in the most complex patient encounters (level 5 E&M visits). The most common ICD-10 code for head-CT without intravenous contrast billed with a level 5 E&M visit was “dizziness and giddiness,” and for head-CT without and with intravenous contrast was “headache.”ConclusionHead-CT is not only most frequently ordered in the ED, but also during the most complex ED visits, suggesting that the ICD-10 codes associated with such exams do not appropriately reflects patient complexity. The valuation process should also consider the complexity of associated billed patient encounters, as indicated by E&M visit levels.     

The DePICTORS Study: discrepancies in preliminary interpretation of CT scans between on-call residents and staff

At many academic hospitals, radiology residents provide preliminary interpretations of CT studies performed outside of regular working hours. We examined the rate of discrepancies between resident interpretations and final reports issued by staff. We prospectively obtained 1,756 preliminary reports and corresponding final reports for computed tomography (CT) scans performed on call between November 2006 and March 2007. The overall rate of clinically significant discrepancies (those that would potentially alter the patient’s clinical course prior to issue of the final report) was 2.0%. Major discrepancy rates for abdominal/pelvic, chest, cervical spine and head CT were 4.1%, 2.5%, 1.0% and 0.7%, respectively. Senior residents had fewer major discrepancies compared to their junior colleagues. Time of interpretation was also evaluated, but a statistically significant relationship was not observed. In summary, this study demonstrates a low discrepancy rate between residents and staff radiologists and identifies areas where after-hours service may be further improved.     

Changing Abdominal Imaging Utilization Patterns: Perspectives From Medicare Beneficiaries Over Two Decades

PurposeTo assess changing utilization patterns of abdominal imaging in the Medicare fee-for-service population over the past two decades.MethodsMedicare Physician Supplier Procedure Summary master files from 1994 through 2012 were used to study changes in the frequency and utilization rates (per 1,000 Medicare beneficiaries per year) of abdominal CT, MRI, ultrasound, and radiography.ResultsIn Medicare beneficiaries, the most frequently performed abdominal imaging modality changed from radiography in 1994 (207.4 per 1,000 beneficiaries) to CT in 2012 (169.0 per 1,000). Utilization rates of abdominal MR (1037.5%), CT (197.0%), and ultrasound (38.0%) all increased from 1994-2012 (but declined briefly from 2007 to 2009). A dramatic 20-year utilization rate decline occurred for gastrointestinal fluoroscopic examinations (–91.9% barium enema, –80.0% upper gastrointestinal series) and urologic radiographic examinations (–95.3%). Radiologists were the dominant providers of all modalities, accounting for >90% of CT and MR studies, and >75% of most ultrasound examination types.ConclusionsMedicare utilization of abdominal imaging has markedly changed over the past two decades, with overall dramatic increases in CT and MRI and dramatic decreases in gastrointestinal fluoroscopic and urologic radiographic imaging. Despite these changes, radiologists remain the dominant providers in all abdominal imaging modalities.     

Diagnostic Radiology Resident and Fellow Workloads: A 12-Year Longitudinal Trend Analysis Using National Medicare Aggregate Claims Data

PurposeThe aim of this study was to evaluate changes in diagnostic radiology resident and fellow workloads in recent years.MethodsBerenson-Eggers Type of Service categorization was applied to Medicare Part B Physician/Supplier Procedure Summary Master Files to identify total and resident-specific claims for radiologist imaging services between 1998 and 2010. Data were extracted and subgroup analytics performed by modality. Volumes were annually normalized for active diagnostic radiology trainees.ResultsFrom 1998 to 2010, Medicare claims for imaging services rendered by radiologists increased from 78,901,255 to 105,252,599 (+33.4%). Service volumes increased across all modalities: for radiography from 55,661,683 to 59,654,659 (+7.2%), for mammography from 5,780,624 to 6,570,673 (+13.7%), for ultrasound from 5,851,864 to 9,853,459 (+68.4%), for CT from 9,351,780 to 22,527,488 (+140.9%), and for MR from 2,255,304 to 6,646,320 (+194.7%). Total trainee services nationally increased 3 times as rapidly. On an average per trainee basis, however, the average number of diagnostic services rendered annually to Medicare Part B beneficiaries increased from 499 to 629 (+26.1%). By modality, this represents an average change from 333 to 306 examinations (−8.1%) for radiography, from 20 to 18 (−7.4%) for mammography, from 37 to 56 (+49.7%) for ultrasound, from 88 to 202 (+129.1%) for CT, and from 20 to 47 (+132.0%) for MRI.ConclusionsBetween 1998 and 2010, the number of imaging examinations interpreted by diagnostic radiology residents and fellows on Medicare beneficiaries increased on average by 26% per trainee, with growth largely accounted for by disproportionate increases in more complex services (CT and MRI).     

Characterizing the Performance of the Nation’s Hospitals in the Hospital Outpatient Quality Reporting Program’s Imaging Efficiency Measures

PurposeTo describe the performance of the nation’s hospitals in terms of the Hospital Outpatient Quality Reporting Program’s imaging efficiency measures.MethodsData were obtained from the Hospital Compare website and reflect outpatient Medicare claims of 4,118 hospitals for 5 imaging efficiency metrics: (1) frequency of combination abdominal CT (performed with and without intravenous contrast); (2) combination chest CT (performed with and without intravenous contrast); (3) simultaneous brain/sinus CT; (4) mammography follow-up (diagnostic imaging after screening mammography); and (5) lumbar spine MRI for low back pain without prior conservative therapy. Metrics were summarized and compared with other hospital characteristics.ResultsMedian frequency was 36.7% for lumbar spine MRI for low back pain and ranged from 1.6% to 7.8% for the remaining measures; however, extreme outliers were observed (maximal frequencies of 79.2%-95.2% for mammography follow-up and combination chest and abdominal CT). Essentially no correlation was found among measures, aside from combination abdominal and chest CT. For some measures, relatively poor performance was more commonly observed among critical access hospitals and physician-owned/proprietary hospitals, and less commonly observed among U.S. News & World Report “best” hospitals and primary residency teaching sites. Frequencies for combination abdominal and chest CT improved from 2013 to 2014 among hospitals with relatively poorer performance.ConclusionsAlthough the imaging efficiency measures help identify individual hospitals and hospital categories with relatively inefficient imaging practices, they do not readily identify distinctly positively performing hospitals. Excess utilization was suggested for lumbar spine MRI. Frequency of combination abdominal and chest CT examinations improved over a short time interval.     

Nationwide Trends in Use of Catheter-Directed Therapy for Treatment of Pulmonary Embolism in Medicare Beneficiaries from 2004 to 2016

PurposeTo evaluate changes in the use of catheter-directed therapy (CDT) for pulmonary embolism (PE) treatment with attention to primary operator specialty in the Medicare population.MethodsUsing a 5% national sample of Medicare claims data from 2004 to 2016, all claims associated with PE were identified. The annual volume of 2 billable CDT services—arterial mechanical thrombectomy and transcatheter arterial infusion for thrombolysis—were determined to evaluate changes in CDT use and primary CDT operator specialty over time.ResultsThe total number of CDT procedures increased over the course of the study period, representing 0.457 and 5.057 service counts per 100,000 Medicare beneficiaries in 2004 and 2016, respectively. The proportion of PEs treated with CDT increased 10-fold from 2004 to 2016, increasing from 0.1% to 1.0%. Interventional radiologists performed most CDT therapies each year, with the exception of 2010 when vascular surgeons performed more. In 2016, interventional radiologists performed 3.54 CDT services for PE per 100,000 Medicare beneficiaries, which was 70% of total CDT for PE procedures, followed by interventional cardiologists and vascular surgeons performing 0.92 services (18%) and 0.60 services (12%), respectively.ConclusionsCDT is an increasingly used treatment for PE, with a 10-fold increase from 2004 to 2016. Interventional radiologists are the dominant providers of these services, followed by interventional cardiologists and vascular surgeons.     

Characteristics of COVID-19 Community Practice Declines in Noninvasive Diagnostic Imaging Professional Work

PurposeThe operational and financial impact of the widespread coronavirus disease 2019 (COVID-19) curtailment of imaging services on radiology practices is unknown. We aimed to characterize recent COVID-19-related community practice noninvasive diagnostic imaging professional work declines.MethodsUsing imaging metadata from nine community radiology practices across the United States between January 2019 and May 2020, we mapped work relative value unit (wRVU)-weighted stand-alone noninvasive diagnostic imaging service codes to both modality and body region. Weekly 2020 versus 2019 wRVU changes were analyzed by modality, body region, and site of service. Practice share χ² testing was performed.ResultsAggregate weekly wRVUs ranged from a high of 120,450 (February 2020) to a low of 55,188 (April 2020). During that −52% wRVU nadir, outpatient declines were greatest (−66%). All practices followed similar aggregate trends in the distribution of wRVUs between each 2020 versus 2019 week (P = .96-.98). As a percentage of total all-practice wRVUs, declines in CT (20,046 of 63,992; 31%) and radiography and fluoroscopy (19,196; 30%) were greatest. By body region, declines in abdomen and pelvis (16,203; 25%) and breast (12,032; 19%) imaging were greatest. Mammography (−17%) and abdominal and pelvic CT (−14%) accounted for the largest shares of total all-practice wRVU reductions. Across modality-region groups, declines were far greatest for mammography (−92%).ConclusionsSubstantial COVID-19-related diagnostic imaging work declines were similar across community practices and disproportionately impacted mammography. Decline patterns could facilitate pandemic second wave planning. Overall implications for practice workflows, practice finances, patient access, and payment policy are manifold.     

National Trends in Oncologic Diagnostic Imaging

ObjectiveTo characterize national trends in oncologic imaging (OI) utilization.MethodsThis retrospective cross-sectional study used 2004 and 2016 CMS 5% Carrier Claims Research Identifiable Files. Radiologist-performed, primary noninvasive diagnostic imaging examinations were identified from billed Current Procedural Terminology codes; CT, MRI, and PET/CT examinations were categorized as “advanced” imaging. OI examinations were identified from imaging claims’ primary International Classification of Diseases-9 and International Classification of Diseases-10 codes. Imaging services were stratified by academic practice status and place of service. State-level correlations of oncologic advanced imaging utilization (examinations per 1,000 beneficiaries) with cancer prevalence and radiologist supply were assessed by Spearman correlation coefficient.ResultsThe national Medicare sample included 5,051,095 diagnostic imaging examinations (1,220,224 of them advanced) in 2004 and 5,023,115 diagnostic imaging examinations (1,504,608 of them advanced) in 2016. In 2004 and 2016, OI represented 4.3% and 3.9%, respectively, of all imaging versus 10.8% and 9.5%, respectively, of advanced imaging. The percentage of advanced OI done in academic practices rose from 18.8% in 2004 to 34.1% in 2016, leaving 65.9% outside academia. In 2016, 58.0% of advanced OI was performed in the hospital outpatient setting and 23.9% in the physician office setting. In 2016, state-level oncologic advanced imaging utilization correlated with state-level radiologist supply (r = +0.489, P < .001) but not with state-level cancer prevalence (r = −0.139, P = .329).DiscussionOI usage varied between practice settings. Although the percentage of advanced OI done in academic settings nearly doubled from 2004 to 2016, the majority remained in nonacademic practices. State-level oncologic advanced imaging utilization correlated with radiologist supply but not cancer prevalence.     

Abdominal and pelvic computed tomography (CT) interpretation: discrepancy rates among experienced radiologists

Objective

To assess the discrepancy rate for the interpretation of abdominal and pelvic computed tomography (CT) examinations among experienced radiologists.

Methods

Ninety abdominal and pelvic CT examinations reported by three experienced radiologists who specialize in abdominal imaging were randomly selected from the radiological database. The same radiologists, blinded to previous interpretation, were asked to re-interpret 60 examinations: 30 of their previous interpretations and 30 interpreted by others. All reports were assessed for the degree of discrepancy between initial and repeat interpretations according to a three-level scoring system: no discrepancy, minor, or major discrepancy. Inter- and intrareader discrepancy rates and causes were evaluated.

Results

CT examinations included in the investigation were performed on 90 patients (43 men, mean age 59 years, SD 14, range 19–88) for the following indications: follow-up/evaluation of malignancy (69/90, 77%), pancreatitis (5/90, 6%), urinary tract stone (4/90, 4%) or other (12/90, 13%). Interobserver and intraobserver major discrepancy rates were 26 and 32%, respectively. Major discrepancies were due to missed findings, different opinions regarding interval change of clinically significant findings, and the presence of recommendation.

Conclusions

Major discrepancy of between 26 and 32% was observed in the interpretation of abdominal and pelvic CT examinations.     

Retrospective Analysis of Emergency Computed Tomography Imaging Utilization at an Academic Centre: An Analysis of Clinical Indications and Outcomes

PurposeTo explore resource utilization through evaluation of computed tomography (CT) imaging trends in the emergency department by examining common indications/outcomes for imaging in this setting.MethodsA retrospective analysis of clinical indications/outcomes for all CT imaging in 3 emergency departments over a 1-year period was conducted. Scans were divided by body part and the most common indications for each type of scan were determined. Clinical outcomes from each study were extracted from final interpretations by the reporting radiologist.ResultsA total of 4556 CT scans were performed in the emergency department over a 1-year period. A total of 3.6% of all-comers to our emergency departments underwent CT scan as part of their investigation. There were 2107 head CTs (46%), 1296 (28%) abdominal CTs, 468 (10%) CTs of the chest, 408 (9%) CTs of the neck/spine, and 101 (2%) extremity CTs performed. The most common clinical indication for performing a CT head was focal neurological defect comprising 1534 (73%) of all CT heads. Twenty-four percent of abdominal CTs were for investigation of right lower quadrant pain, followed by flank pain (19%). Chest pain and shortness of breath were the most common indications for CTs of the chest (315 [75%]) with 10% of these examinations for this indication positive for pulmonary embolism. Trauma was the most common indication for neck CTs (296 [73%]) and extremities (70 [69%]). Nil acute was the most common final interpretation in all categories (79% CT heads, 75% neck CTs, 38% abdominal CTs, 43% chest CTs).ConclusionsNil acute was the most common diagnosis; however, serious clinical outcomes were identified 40% of the time. Cross-sectional imaging remains an integral tool for triage and diagnosis in this environment as the cost of missing a diagnosis in this setting has a great impact on patient care.     

Body MR imaging and CT volume: variations and trends based on an analysis of medicare and fee-for-service health insurance databases

OBJECTIVE: We examined Medicare and fee-for-service data sets to understand better the utilization of MR imaging for imaging the pelvis, abdomen, and chest relative to its use in imaging for other body parts and to the utilization of CT. MATERIALS AND METHODS: CT and MR imaging procedure volumes for pelvis, abdomen, chest, and total were extracted from the 1993, 1996, and 1999 Health Care Financing Administration Physician/Supplier Procedure Summary Master Files, based on CPT-4 codes. We also analyzed a fee-for-service health insurance database for January 1998 through July 1999 from a single northeastern state, which included provider location (rural, suburban, or urban) and type (teaching or nonteaching site). RESULTS: The greatest 3-year Medicare increase was for abdominal MR imaging, from 1996 to 1999 (101% increase). However, pelvic, abdominal, and chest MR imaging together remained less than 5% of total MR imaging. Abdominal MR imaging increased more than did total MR imaging in all 10 Health Care Financing Administration regions. In the fee-for-service database, the relative procedure volume of abdominal MR imaging varied approximately fivefold from rural to urban provider locations, and approximately double from nonteaching to teaching hospitals. CONCLUSION: Although far more abdominal CT than abdominal MR imaging is performed, the rate of abdominal MR imaging utilization has increased more rapidly since 1993. The relative procedure volume of abdominal MR imaging varied more than fivefold from rural to urban provider locations and double from nonteaching to teaching hospitals.     

Trends in Diagnostic Imaging by Nonphysician Practitioners and Associations With Urbanicity and Scope-of-Practice Authority

ObjectiveWe aimed to assess the changing share of diagnostic imaging billed by NPPs and how such changes differ by urbanicity within the context of scope-of-practice (SOP) regulations and legislation.MethodsThis retrospective cohort study used patient claims for diagnostic imaging studies spanning 2016-2020 from Optum Clinformatics Datamart datasets. Multivariable modeling determined the odds of patients receiving NPP-interpreted vs physician-interpreted imaging. Imaging rates and trends in proportions of NPP-billed claims were assessed by urbanicity and relative to other factors including SOP, imaging modality, and place of service.ResultsOf all identified imaging claims, 3,348,881 (3.0%) were attributed to NPPs, with the highest rates of NPP interpretations per 10,000 images occurring in rural and small-town areas. From 2016 to 2020, the rate of NPP-billed imaging increased from 257 to 331 claims per 10,000 beneficiaries (P = 0.004), observed across both metropolitan (240 to 315, P = 0.001) and micropolitan (367 to 436, P = 0.020) settings. Although rates in rural and small-town areas rose, the increase was not significant (330 to 392, P = 0.363). Rises in NPP imaging in metropolitan settings occurred in states with moderately restrictive (307 to 358, P = 0.008) and least restrictive (289 to 419, P = 0.004) SOP legislation.DiscussionRates of diagnostic imaging interpretation by NPPs are rising. Growth in recent years appears driven by metropolitan areas in states with less restrictive SOP regulations. Future work is necessary to assess the quality of and downstream costs related to increasing NPP-interpreted imaging.     

National Trends in the Utilization of Skeletal Radiography From 2003 to 2015

PurposeExamine recent trends in the use of skeletal radiography and assess the roles of various nonradiologic specialties in the interpretations.MethodsMedicare Part B fee-for-service claims data files from 2003 to 2015 were analyzed for all Current Procedural Terminology, version 4 (CPT-4) procedure codes related to skeletal radiography. The files provide examination volume, and we calculated utilization rates per 1,000 Medicare beneficiaries. Medicare’s physician specialty codes were used to determine the specialties of the providers. Total utilization rate trends were analyzed, as well as those for radiologists and nonradiologists. We determined which nonradiologist specialties were the highest users of skeletal radiography. Medicare place-of-service codes were used to identify the locations where the services were provided.ResultsThe total utilization rate per 1,000 of skeletal radiography within the Medicare population increased 9.5% from 2003 to 2015. The utilization rate for radiologists increased 5.5% from 2003 to 2015 versus 11.1% for nonradiologists as a group. Among nonradiologist specialties in all health care settings over the study period, orthopedic surgeons increased 10.6%, chiropractors and podiatrists together increased 14.4%, nonphysician providers (primarily nurse practitioners and physician assistants) increased 441%, and primary care physicians’ rate decreased 33.5%. Although radiologists do almost all skeletal radiography interpretation in hospital settings, nonradiologists do the majority in private offices. There has been strong growth in skeletal radiography in emergency departments, but a substantial drop in inpatient settings.ConclusionsThe utilization of skeletal radiography has increased more rapidly among nonradiologists than among radiologists. This raises concerns about self-referral and quality.     

Discrepancy Rates and Clinical Impact of Imaging Secondary Interpretations: A Systematic Review and Meta-Analysis

PurposeTo conduct a meta-analysis of studies investigating discrepancy rates and clinical impact of imaging secondary interpretations and to identify factors influencing these rates.MethodsEMBASE and PubMed databases were searched for original research investigations reporting discrepancy rates for secondary interpretations performed by radiologists for imaging examinations initially interpreted at other institutions. Two reviewers extracted study information and assessed study quality. Meta-analysis was performed.ResultsTwenty-nine studies representing a total of 12,676 imaging secondary interpretations met inclusion criteria; 19 of these studies provided data specifically for oncologic imaging examinations. Primary risks of bias included availability of initial interpretations, other clinical information, and reference standard before the secondary interpretation. The overall discrepancy rate of secondary interpretations compared with primary interpretations was 32.2%, including a 20.4% discrepancy rate for major findings. Secondary interpretations were management changing in 18.6% of cases. Among discrepant interpretations with an available reference standard, the secondary interpretation accuracy rate was 90.5%. The overall discrepancy rates by examination types were 28.3% for CT, 31.2% for MRI, 32.7% for oncologic imaging, 43.8% for body imaging, 39.9% for breast imaging, 34.0% for musculoskeletal imaging, 23.8% for neuroradiologic imaging, 35.5% for pediatric imaging, and 19.7% for trauma imaging.ConclusionMost widely studied in the context of oncology, imaging secondary interpretations commonly result in discrepant interpretations that are management changing and more accurate than initial interpretations. Policymakers should consider these findings as they consider the value of, and payment for, secondary imaging interpretations.     

Changing Utilization Patterns of Cervical Spine Imaging in the Emergency Department: Perspectives From Two Decades of National Medicare Claims

PurposeThe aim of this study was to assess the changing use of emergency department (ED) cervical spine imaging in the Medicare population.MethodsUsing national aggregate Medicare claims data from 1994 through 2012, all cervical spine radiographic, CT, and MR examinations performed in the ED setting were identified. Shifts in modalities and providers and changes in utilization rates were studied.ResultsBetween 1994 and 2004, ED cervical spine radiography volumes in the Medicare fee-for-service population increased from 203,645 to 306,442 (+50.5%) and then declined to 152,755 (−50.2%) by 2012. CT volumes increased every year, overall by +8,864% from 1994 through 2012 (from 6,360 to 570,121). MR grew by +1,381%, but volumes overall were small (from 944 to 13,979). With these changes, CT overtook radiography as the dominant ED cervical spine imaging modality in 2007. Per 1,000 Medicare beneficiaries, utilization rates of radiography, CT, and MR changed by −27%, +8,682%, and +1,351% from 1994 through 2012 (from 6.3 to 4.6, from 0.2 to 17.3, and from 0.0 to 0.4). For all years, compared with other specialists, radiologists remained by far the dominant providers of radiography, CT, and MR (+91.7%, +93.4%, and +96.0% in 1994 and +96.9%, +99.3%, and +99.0% in 2012) in the ED setting.ConclusionsBetween 1994 and 2012, the overall utilization rate of cervical spine imaging for Medicare beneficiaries in the ED setting more than tripled. With a small decline in radiography (–27%) but a dramatic increase in CT (+8,864%), CT is now by far the dominant modality for imaging the cervical spine in the ED. Radiologists remain overwhelmingly the dominant providers of these interpretive services.     

Strategies for Avoiding Recommendations for Additional Imaging Through a Comprehensive Comparison With Prior Studies

PurposeTo determine the frequency and characteristics of recommendations for additional imaging and/or intervention (RAIs) in abdominal CT and MRI interpretations that might be avoided through comprehensive comparison with all available prior examinations.MethodsA total of 1,006 RAIs in abdominopelvic CT and MRI reports were retrospectively evaluated. Reports and images from each patient’s prior imaging examinations, including those of all relevant body parts and modalities, were reviewed to determine if the RAI could have been avoided based on prior imaging. Frequency and characteristics of such “avoidable” RAIs were evaluated.ResultsA total of 41 of 1,006 (4.1%) RAIs were avoidable. The key prior examination that established the RAI as avoidable was a different modality in 53.7% (22 of 41) and on a different body area in 41.5% (17 of 41) of cases, including chest imaging in 31.7% (13 of 41). A total of 83.3% (5 of 6) adrenal RAIs, and 80.0% (4 of 5) liver RAIs were avoidable based on prior chest imaging. The key finding was present on the prior images but was not described in the report in 46.3% (19 of 41) of cases. A greater number of prior examinations were available in cases of avoidable RAIs (mean, 12.2 ± 16.7) than in those of nonavoidable RAIs (mean, 5.7 ± 9.5) (P < .001).ConclusionsA small fraction of RAIs can be avoided by performing a thorough evaluation of all prior imaging examinations, including different modalities and body parts. Nearly half of the key prior examinations did not report the finding, highlighting the importance of directly reviewing relevant images, particularly chest imaging for evaluation of indeterminate upper-abdominal findings. Configuration of PACS for optimized selection and display of relevant examination reports and images may facilitate such comparisons.