Malignant incidental extracardiac findings on cardiac CT: systematic review and meta-analysis

Prevalence and Clinical Implications of Incidental Aortic Arch Abnormalities on Contrast-Enhanced Neck MR Angiography: A Single-Center Experience

Background and Objectives: Vascular abnormalities within the anatomical coverage are frequently encountered in imaging studies. The aortic arch is often overlooked as an anatomical blind spot, especially in neck magnetic resonance (MR) angiography. This study investigated the prevalence of incidental aortic arch abnormalities. We also estimated the potential clinical significance of aortic arch abnormalities as blind spots detected on contrast-enhanced neck MR angiography. Materials and Methods: Between February 2016 and March 2023, 348 patients were identified based on contrast-enhanced neck MR angiography reports. The clinical and radiological characteristics of the patients and the presence of additional imaging studies were assessed. The aortic arch abnormalities and coexisting non-aortic arterial abnormalities were classified into two categories according to their clinical significance. We performed the χ² test and Fisher's exact test for group comparisons. Results: Of the 348 study patients, only 29 (8.3%) had clinically significant incidental aortic arch abnormalities. Among these 348 patients, 250 (71.8%) and 136 (39%) had intracranial and extracranial abnormalities, respectively; the clinically significant intracranial abnormalities in the two groups were 130 lesions (52.0%) and 38 lesions (27.9%), respectively. In addition, there was a significantly higher tendency of clinically significant aortic arch abnormalities (13/29, 44.8%) in the patients who had clinically significant coexisting non-aortic arterial abnormalities than in the other group (87/319, 27.3%) (p = 0.044). The patient groups with clinically significant intracranial or extracranial arterial abnormalities had higher rates of clinically significant aortic abnormalities (31.0% and 17.2%), but there was no statistical significance (p = 0.136). Conclusions: The incidence of clinically significant aortic arch abnormalities was 8.3% on neck MR angiography, with a significant association between aortic and coexisting non-aortic arterial abnormalities. The findings of this study could improve the understanding of incidental aortic arch lesions on neck MR angiography, which is of crucial clinical importance for radiologists to achieve accurate diagnoses and management.

Detection efficacy of analog [18F]FDG PET/CT, digital [18F]FDG, and [13N]NH3 PET/CT: a prospective, comparative study of patients with lung adenocarcinoma featuring ground glass nodules

OBJECTIVES

This prospective study compared the detection efficacy of analog ¹⁸F-fluoro-2-deoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) (aF PET/CT), digital [¹⁸F]FDG PET/CT (dF PET/CT), and digital ¹³N-ammonia (¹³N-NH₃) PET/CT (dN PET/CT) for patients with lung adenocarcinoma featuring ground glass nodules (GGNs).

METHODS

Eighty-seven patients with lung adenocarcinoma featuring GGNs who underwent dF and dN PET/CT were enrolled. Based on the GGN component, diameter, and solid-part size, 87 corresponding patients examined using aF PET/CT were included, with age, sex, and lesion characteristics closely matched. Images were visually evaluated, and the tumor to background ratio (TBR) was used for semi-quantitative analysis.

RESULTS

Ultimately, 40 and 47 patients with pure GGNs (pGGNs) and mixed GGNs (mGGNs), respectively, were included. dF PET/CT revealed more positive lesions and higher tracer uptake in GGNs than did aF PET/CT (53/87 vs. 26/87, p < 0.05; TBR: 3.08 ± 4.85 vs. 1.42 ± 0.93, p < 0.05), especially in mGGNs (44/47 vs. 26/47, p < 0.05; TBR: 4.48 ± 6.17 vs. 1.78 ± 1.16, p < 0.05). However, dN PET/CT detected more positive lesions than did dF PET/CT (71/87 vs. 53/87, p < 0.05), especially in pGGNs (24/40 vs. 9/40, p < 0.05).

CONCLUSIONS

dF PET/CT provides superior detection efficacy over aF PET/CT for patients with lung adenocarcinoma featuring GGNs, particularly mGGNs. dN PET/CT revealed superior detection efficacy over dF PET/CT, particularly in pGGNs. aF, dF, and dN PET/CT are valuable non-invasive examinations for lung cancer featuring GGNs, with dN PET/CT offering the best detection performance.

KEY POINTS

• Digital PET/CT provides superior detection efficacy over analog PET/CT in patients with lung adenocarcinoma featuring GGNs. • dN PET/CT can offer more help in the early detection of malignant GGN.

Every cloud has a silver lining: COVID-19 chest-CT screening prevents unnecessary cardiac surgery

BACKGROUND

Unenhanced chest CT can identify incidental findings (IFs) leading to management strategy change. We report our institutional experience with routine chest-CT as preoperative screening tool during the COVID-19 pandemic, focusing on the impact of IFs.

METHODS

All patients scheduled for cardiac surgery from May 1st to December 31^st 2020, underwent preoperative unenhanced chest-CT according to COVID-19 pandemic institutional protocol. We have analyzed IFs incidence, reported consequent operative changes, and identified IFs clinical determinants.

RESULTS

Out of 447, 278 patients were included. IFs rate was 7.2% (20/278): a solid mass (11/20, 55%), lymphoproliferative disease (1/20, 5%), SARS-CoV-2 pneumonia (2/20, 10%), pulmonary artery chronic thromboembolism (1/20, 5%), anomalous vessel anatomy (2/20, 10%), voluminous hiatal hernia (1/20, 5%), mitral annulus calcification (1/20, 5%), and porcelain aorta (1/20, 5%) were reported. Based on IFs, 4 patients (20%-4/278, 1.4%) were not operated, 8 (40%-8/278, 2.9%) underwent a procedure different from the one originally planned one, and 8 (40%-8/278, 2.9%) needed additional preoperative investigations before undergoing the planned surgery. At univariate regression, coronary artery disease, atrial fibrillation, and history of cancer were significantly more often present in patients presenting with significant IFs. History of malignancy was identified as the only independent determinant of significant IFs at chest-CT (OR=4.27 IQR: [1.14-14.58], P=0.0227).

CONCLUSIONS

Unenhanced chest-CT as a preoperative screening tool in cardiac surgery led to incidental detection of significant clinical findings, which justified even procedures cancellation. Malignancy history is a determinant for CT incidental findings and could support a tailored screening approach for high-risk patients.

Prevalence and Clinical Impact of Incidental Findings on Preoperative 3D Planning Computed Tomography for Total Shoulder Arthroplasty

Introduction:

3D planning software for shoulder arthroplasty recently emerged for aiding in intraoperative determination of native glenoid. These protocols often require increased scan resolution, however, raising the question of an increased prevalence and clinical impact of incidental findings (IFs) from preoperative imaging.

Methods:

A retrospective review of preoperative shoulder CT reports was conducted for 333 consecutive patients planning anatomic or reverse total shoulder arthroplasties. Patients with thin-sliced CT scans (1.25 mm) were compared with those with standard CT scans (2.5 mm). Poisson regression was performed with baseline characteristics and potentially pathologic IFs (PPIFs).

Results:

IFs were present in 131 of the 333 scans (39.3%), and 38 of the 333 scans (11.4%) included PPIFs. Only 8 of the 333 scans (2.4%) required workup, with 2 of the 333 (0.6%) leading to new cancer diagnoses. Thin-sliced CT scans detected a higher mean number of IFs (1.12 versus 0.22, P < 0.001) while the mean number of PPIFs remained similar (0.13 versus 0.10, P = 0.43).

Conclusion:

IFs are frequent; however, only 0.6% scans led to new cancer diagnoses. Comparison of thin-sliced with standard CT scans revealed a higher frequency of IFs but similar PPIFs, indicating increased burden of IFs without the benefit of identifying additional malignancies. As demand rises for shoulder arthroplasties, surgeons should consider the potential hidden costs of IFs when using 3D planning programs.

Prevalence and clinical significance of incidental findings on CT attenuation correction for myocardial perfusion imaging

BACKGROUND

The appropriate clinical approach to incidentally detected lesions (IDLs) on CT attenuation correction (CTAC) images in myocardial perfusion imaging (MPI) remains uncertain. We sought to establish their prevalence and clinical significance in a large cohort and compared to previous studies to help provide further clarity and guide future clinical practice.

METHODS AND RESULTS

A total of 3758 MPI studies were reviewed retrospectively. IDLs of potential clinical significance-not known before MPI - were reported in 245 (6.5%) of these cases. Following appropriate further investigation/follow-up, these were of proven clinical significance in 30 (12.2%) cases with 14 patients (5.7%) harboring previously undiagnosed or progressive malignancies. The positive predictive value (PPV) for clinically significant incidental findings on CTAC images was 17.2% and the PPV value for incidental malignant findings was 8.0%.

CONCLUSION

Although incidental findings on CTAC images in MPI are common and often clearly insignificant at time of MPI reporting, many are clinically significant with a relatively high positive predictive value. This is especially so for malignancies. Our findings, therefore, in combination with previous studies as described here support routine reporting and appropriate further investigation of incidental CTAC findings in MPI.

Prevalence and Clinical Implications of Incidentally Detected Parotid Lesions as Blind Spot on Brain MRI: A Single-Center Experience

Background and objective: This study was conducted to assess the prevalence and clinical implications of parotid lesions detected incidentally during brain magnetic resonance imaging (MRI) examination. Materials and Methods: Between February 2016 and February 2021, we identified 86 lesions in the brain MRI reports of 84 patients that contained the words “parotid gland” or “PG”. Of these, we finally included 49 lesions involving 45 patients following histopathological confirmation. Results: Based on the laboratory, radiological or histopathological findings, the prevalence of incidental parotid lesions was low (1.2%). Among the 45 study patients, 41 (91.1%) had unilateral lesions, and the majority of the lesions were located in the superficial lobe (40/49, 81.6%). The mean size of the parotid lesions was 1.3 cm ± 0.4 cm (range, 0.5 cm–2.8 cm). Of these, 46 parotid lesions (93.9%) were benign, whereas the remaining three lesions were malignant (6.1%). Conclusions: Despite the low prevalence and incidence of malignancy associated with incidental parotid lesions detected on brain MRI, the clinical implications are potentially significant. Therefore, clinical awareness and appropriate imaging work-up of these lesions are important for accurate diagnosis and timely management.

Coronary Artery Disease Reporting and Data System: A Comprehensive Review

The Coronary Artery Disease Reporting and Data System (CAD-RADS) is a standardized reporting method for coronary computed tomography angiography (CCTA). It summarizes the findings of CCTA in 6 categories ranging from CAD-RADS 0 (complete absence of coronary artery disease) to CAD-RADS 5 (total occlusion of at least one vessel). It is applied on per patient basis for the highest grade of the stenotic lesion. The CAD-RADS also provides category-specific treatment recommendations, helping patient management. The main objectives of the CAD-RADS are to improve the consistency in reporting, facilitate the communication between interpreting and referring clinicians, recommend the best course of patient management, and produce consistent data for quality improvement, research and education. However, CAD-RADS has many limitations, resulting into the misclassification of the observed findings, misinterpretation of the final category, and misguidance for the treatment based upon the single score. In this review, the authors discuss the CAD-RADS categories and modifiers, along with the strengths and limitations of this new classification system.

Incidental Findings of Malignancy of the Chest by Single Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT-CT MPI): One Year Follow-Up Report

Introduction

We recently reported six cases of pulmonary/hilar malignancies as the result of incidental findings (IF) on CT attenuation correction (CTAC) during Single Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT-CT MPI). In this study, clinical features, diagnostic procedures, and clinical outcomes were examined on all patients who had malignancies or significant IF that required further follow-up.

Methods

Of 1,098 consecutive patients who underwent cardiac SPECT-CT MPI from September 1, 2017 to August 31, 2018, their MPI and CTAC were reviewed contemporaneously. Patients with known history of prior pulmonary or chest malignancy were excluded.

Results

A total of 79 (7.2%) patients were identified to have significant IF on CTAC. After diagnostic CT, 47 patients had significant findings that warranted further follow-up and included in this study. Eight of 1,098 patients (0.73%) and 8/79 patients (10.1%) were found to have malignancy of the chest because of IF on the CTAC. There were no statistically significant differences in baseline characteristics and cancer risk factors among patients who had cancer versus those without. At the time of diagnosis, four patients had cancer at an advanced stage, resulting in death within 12 months. Three others had early stage lung cancer and one had mantle cell lymphoma; they were alive at a mean follow-up of 17.5+/−2.1 months. Biopsy for tissue diagnosis was performed safely with needle biopsy. Major complication occurred in one patient (1/9 or 11.1%) with needle biopsy; none with surgical biopsy.

Conclusion

This study underscored the importance of reviewing CTAC images obtained during cardiac SPECT-CT MPI to detect clinically important IF.

Clinical significance of incidental findings on coronary CT angiography: Insights from a randomized controlled trial

BACKGROUND

The effect of incidental findings from coronary computed tomography angiography (CCTA) on management has not been rigorously investigated. This study uses a control group to explore this relationship.

METHODS

Analysis of data from a randomized controlled trial of acute chest pain patients admitted to telemetry was performed. Patients were randomized to undergo either CCTA (n = 200) or radionuclide myocardial perfusion imaging (MPI) (n = 200). Incidental findings were determined from imaging reports. Records were reviewed to determine subsequent management and imaging during and after hospitalization. Comparisons were performed using Fischer's exact tests.

RESULTS

386 incidental findings were found among 187 CCTA studies. No extra-cardiac incidental findings were noted in the MPI arm, which served as an effective control group. There were significantly more non-coronary medical workups during admission in the CCTA group compared to the MPI group [20% (39) vs. 12% (23), P = 0.038]. CCTA patients underwent significantly more resting echocardiography during the inpatient workup compared to the MPI group [38% (75) vs. 18% (55), P = 0.042]. CCTA patients underwent significantly more non-contrast chest CT exams in the year following admission compared to MPI patients [14% (27) vs. 7% (13) P = 0.029].

CONCLUSIONS

Incidental findings on inpatient CCTAs performed for chest pain have a significant impact on treatment and imaging during and following hospital admission.

CAD-RADS: Pushing the Limits

Coronary CT angiography is now established as the first-line diagnostic imaging test to exclude coronary artery disease (CAD) in the population at low to intermediate risk. Wide variability exists in both the reporting of coronary CT angiography and the interpretation of these reports by referring physicians. The CAD Reporting and Data System (CAD-RADS) is sponsored by multiple societies and is a collaborative effort to provide standard classification of CAD, which is then integrated into patient clinical care. The main goals of the CAD-RADS are to decrease variability among readers; enhance communication between interpreting and referring clinicians, allowing collaborative determination of the best course of patient care; and generate consistent data for auditing, data mining, quality improvement, research, and education. There are several scenarios in which the CAD-RADS guidelines are ambiguous or do not provide definite recommendations for further management of CAD. The authors discuss the CAD-RADS categories and modifiers, highlight a variety of complex or ambiguous scenarios, and provide recommendations for managing these scenarios. Online supplemental material is available for this article. ^©RSNA, 2020 See discussion on this article by Aviram and Wolak.

Incidental Non-cardiac Findings in Cardiovascular Imaging

Improvements in imaging techniques have led to an expansion in the number of cross-sectional cardiac studies being performed. This means that incidental non-cardiac findings (INCF) identified on cardiac imaging have become an important clinical concern. The majority of INCF are not clinically significant. However, some INCF will require follow-up or changes in management. Differentiating clinically significant from non-significant INCF can be challenging, particularly given the breadth of potential findings and the range of organ systems involved. Following up INCF also has economic implications. Recent changes to the lung nodule follow-up guidelines will reduce the cost of following up incidental lung nodules. In this manuscript, we discuss the common and important INCF which may be identified in cardiovascular imaging and explore potential implications of these findings.

Computed tomography coronary angiography in patients without known coronary artery disease can demonstrate possible non-cardiovascular causes of non-acute retrosternal chest pain

OBJECTIVES

To assess the computed tomography coronary angiography (CTCA) accuracy for demonstrating possible non-cardiovascular causes of non-acute retrosternal chest pain in patients without known coronary artery disease (CAD) and to correlate CTCA results with the patient management and relief from pain.

METHODS

This prospective observational study was approved by the ethical committee. Consecutive patients suffering non-acute chest pain who underwent CTCA and with not known CAD were enrolled and classified as having coronary diseases (CD) or extracardiac diseases (ECD). Association between age, sex, body mass index (BMI), cardiovascular risk factors, and type of chest pain with CD or ECD was estimated. Correlation between BMI classes and each risk factor was also calculated.

RESULTS

A total of 106 patients (60 males; age 62 ± 14 years [mean ± standard deviation]; mean BMI 27) were enrolled. Hypertension was found in 71/106 (67%); smoking was significantly more frequent among males (p = 0.003) and hypercholesterolemia among females (p = 0.017); hypertension and hypercholesterolemia significantly correlated with age, and hypertension also with BMI. Pain was atypical in 70/106 (66%) patients. The kind of pain did not correlate with disease or gender. CTCA showed possible causes of chest pain in 69/106 (65%) patients; 32/69 (47%) having only CD, 23/69 (33%) only ECD, and 14/69 (20%) both CD and ECD. Prevalence was: hiatal hernia 35/106 (33%); significant CAD 24/106 (23%); myocardial bridging 22/106 (21%). At follow-up of 94/106 (89%) patients, 71/94 (76%) were pain-free, 14/17 (82%) significant CAD had been treated, and only one patient with non-significant CAD was treated after CTCA.

CONCLUSION

CTCA suggested possible causes of non-acute pain in 65% of patients.

MAIN MESSAGES

• CTCA can either rule in or rule out possible causes of chest pain alternative to CAD. • Clinically relevant findings were detected in 65% of patients with non-acute chest pain. • Non-cardiovascular diseases potentially explained symptoms in 35% of patients.

Prognostic impact of myocardial perfusion single photon emission computed tomography in patients with major extracardiac findings by computed tomography for attenuation correction

BACKGROUND

Attenuation correction computed tomography (CT) contributes to an improvement in the diagnostic accuracy of myocardial perfusion imaging (MPI) by single photon emission tomography (SPECT). The aim of this study was to explore the prognosis of patients with major findings by CT according to the results of MPI.

METHODS AND RESULTS

1506 patients who underwent MPI by SPECT were retrospectively included. Attenuation correction CT images were systematically analyzed for major and minor abnormalities. 830 (55.1%) and 212 (14.1%) patients had minor and major extracardiac findings, respectively. Among patients with major extracardiac findings, the abnormality was previously unknown in 113 (53.3%) patients. 90 (41.9%) had abnormal MPI, 73 (34.4%) had a myocardial infarction scar, 55 (25.9%) had myocardial ischemia, and 38 (17.7%) patients had both myocardial infarction scar and myocardial ischemia. Among the 201 patients available for survival analysis, there were 67 (31.2%) deaths over a follow-up period of 3.2±1.3 years. There was no significant impact on survival arising from MPI, whatever the result. The results were the same among the 103 patients with previously unknown major extracardiac findings.

CONCLUSION

Extracardiac findings by CT during MPI are frequent. Patients with major extracardiac findings have a poor mid-term outcome, whatever the results of the myocardial perfusion imaging. Extracardiac findings should be systematically checked when attenuation correction CT is performed.

Extracardiac findings on coronary computed tomography angiography in patients without significant coronary artery disease

OBJECTIVE

To analyse extracardiac findings in patients without significant coronary artery disease (CAD) in general and in symptomatic patients in particular.

METHODS

We searched the Radiology Information System database for coronary computed tomography angiographies (CTA) performed from 2000-2014 and retrospectively enrolled 3,898 patients without significant CAD (coronary stenosis < 50%) in CTA. In 2,330 symptomatic patients, we analysed the spectrum of extracardiac findings and identified pathologies potentially explaining chest pain. Finally, we investigated variables affecting the number of extracardiac findings detected in CTA.

RESULTS

Overall extracardiac findings were found in 1,177 patients (30.2%; 95%CI, 28.8-31.7%). 94 patients (2.4%; 95%CI, 2.0-2.9%) had extracardiac findings with a recommendation for follow-up, sixteen patients (0.4%; 95%CI, 0.3-0.7%) had incidental urgent, and another three patients (0.1%; 95%CI, 0.1-0.2%) had incidental malignant extracardiac findings. 185 of 2,330 symptomatic patients (7.9%; 95%CI, 6.9-9.1%) revealed extracardiac findings potentially explaining chest pain after exclusion of significant CAD. The number of extracardiac findings increased significantly with patient age (p < 0.001) and the cumulative experience of the CT reader (p < 0.001).

CONCLUSION

30.2% of patients undergoing CTA for exclusion of CAD had ECF, and 7.9% of symptomatic patients without significant CAD on their examination had findings that could potentially explain their symptoms.

KEY POINTS

• Of patients undergoing CTA, 2.8% have relevant incidental extracardiac findings. • CTA could identify the differential diagnosis of chest pain when excluding significant CAD. • Patient age and reader's professional experience influence the number of detected ECFs.

Prevalence and outcomes of incidental imaging findings: umbrella review

OBJECTIVE

To provide an overview of the evidence on prevalence and outcomes of incidental imaging findings.

DESIGN

Umbrella review of systematic reviews.

DATA SOURCES

Searches of MEDLINE, EMBASE up to August 2017; screening of references in included papers.

ELIGIBILITY CRITERIA

Criteria included systematic reviews and meta-analyses of observational studies that gave a prevalence of incidental abnormalities ("incidentalomas"). An incidental imaging finding was defined as an imaging abnormality in a healthy, asymptomatic patient or an imaging abnormality in a symptomatic patient, where the abnormality was not apparently related to the patient's symptoms. Primary studies that measured the prevalence of incidentalomas in patients with a history of malignancy were also considered in sensitivity analyses.

RESULTS

20 systematic reviews (240 primary studies) were identified from 7098 references from the database search. Fifteen systematic reviews provided data to quantify the prevalence of incidentalomas, whereas 18 provided data to quantify the outcomes of incidentalomas (13 provided both). The prevalence of incidentalomas varied substantially between imaging tests; it was less than 5% for chest computed tomography for incidental pulmonary embolism in patients with and without cancer and whole body positron emission tomography (PET) or PET/computed tomography (for patients with and without cancer). Conversely, incidentalomas occurred in more than a third of images in cardiac magnetic resonance imaging (MRI), chest computed tomography (for incidentalomas of thorax, abdomen, spine, or heart), and computed tomography colonoscopy (for extra-colonic incidentalomas). Intermediate rates occurred with MRI of the spine (22%) and brain (22%). The rate of malignancy in incidentalomas varied substantially between organs; the prevalence of malignancy was less than 5% in incidentalomas of the brain, parotid, and adrenal gland. Extra-colonic, prostatic, and colonic incidentalomas were malignant between 10% and 20% of the time, whereas renal, thyroid, and ovarian incidentalomas were malignant around a quarter of the time. Breast incidentalomas had the highest percentage of malignancy (42%, 95% confidence interval 31% to 54%). Many assessments had high between-study heterogeneity (15 of 20 meta-analyses with I² >50%).

CONCLUSIONS

There is large variability across different imaging techniques both in the prevalence of incidentalomas and in the prevalence of malignancy for specific organs. This umbrella review will aid clinicians and patients weigh up the pros and cons of requesting imaging scans and will help with management decisions after an incidentaloma diagnosis. Our results can underpin the creation of guidelines to assist these decisions.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO: CRD42017075679.

Incidental findings in CT imaging of coronary artery bypass grafts: results from a Canadian multicenter prospective cohort

Objective

To assess the prevalence and clinical significance of incidental findings identified during computed tomography imaging of coronary artery bypass grafts.

Results

This prospective study includes 144 patients undergoing coronary graft patency assessment using computed tomography. Incidental findings were classified as significant if they were considered to need an immediate action or treatment, short-term work-up or follow-up, or minor. A total of 211 incidental findings were present in 109 (75.7%) patients. Seventy-one incidental findings (33.6%) were cardiac and 140 (66.4%) were extracardiac. Most common cardiac incidental findings were atrial dilatation [39 patients, 48 incidental findings (67.6%)] and aortic valve calcifications (7 patients, 9.9%). Among the 140 extracardiac incidental findings, the most common were lung nodules (51 patients, 54 nodules, 38.6%), and emphysema (21 patients, 15%). Thirty-six (25.7%) extracardiac incidental findings were significant and notably, 23 (63.9%) were lung nodules. Follow-up was recommended in 37 cases, among which all patients with significant lung nodules (23 patients, 62.2%). In conclusion, most common computed tomography incidental findings in patients with coronary grafts were lung nodules and emphysema.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3168-1) contains supplementary material, which is available to authorized users.

Incidental extra-cardiac findings on 13N-ammonia myocardial perfusion PET/CT

BACKGROUND

The objective of this study was to describe the prevalence of incidental extra-cardiac findings (IECFs) on myocardial perfusion PET/CTs and the prevalence of potentially clinically relevant and clinically irrelevant IECFs, as well as detection rate of previously unknown malignancies.

METHODS AND RESULTS

From September 2013 until February 2016, a total of 1397 consecutive patients referred for the evaluation of possible ischemia by 13NH3 PET/CT were prospectively included in a database. IECFs were categorized into three groups: potentially clinically relevant IECFs, IECFs that could potentially cause chest pain, and clinically irrelevant IECFs. Additionally, the prevalence of previously unknown malignancies was determined. In 717 (51%) of these patients, 775 IECFs were reported and 115 IECFs were categorized as potentially clinically relevant in 109 (8%) patients. A total of 145 IECFs that could potentially cause chest pain were detected in 139 (10%) patients and 515 clinically irrelevant IECFs were detected in 469 (34%) of the patients. An unknown primary malignancy was histologically proven in 19 patients (1.4%).

CONCLUSIONS

IECFs are detected on myocardial perfusion PET/CT in approximately half of the patients. In the present study, IECFs were potentially clinically relevant in 8% of the patients and in 1.4% an unknown malignancy was found, most of which were lung cancers.

Trends in radiology and experimental research

European Radiology Experimental, the new journal launched by the European Society of Radiology, is placed in the context of three general and seven radiology-specific trends. After describing the impact of population aging, personalized/precision medicine, and information technology development, the article considers the following trends: the tension between subspecialties and the unity of the discipline; attention to patient safety; the challenge of reproducibility for quantitative imaging; standardized and structured reporting; search for higher levels of evidence in radiology (from diagnostic performance to patient outcome); the increasing relevance of interventional radiology; and continuous technological evolution. The new journal will publish not only studies on phantoms, cells, or animal models but also those describing development steps of imaging biomarkers or those exploring secondary end-points of large clinical trials. Moreover, consideration will be given to studies regarding: computer modelling and computer aided detection and diagnosis; contrast materials, tracers, and theranostics; advanced image analysis; optical, molecular, hybrid and fusion imaging; radiomics and radiogenomics; three-dimensional printing, information technology, image reconstruction and post-processing, big data analysis, teleradiology, clinical decision support systems; radiobiology; radioprotection; and physics in radiology. The journal aims to establish a forum for basic science, computer and information technology, radiology, and other medical subspecialties.

Prognostic value of coronary CTA vs. exercise treadmill testing: results from the Partners registry

AIMS

We sought to compare the complementary prognostic value of exercise treadmill testing (ETT) and coronary computed tomographic angiography (CTA) among patients referred for both exams.

METHODS AND RESULTS

We studied 582 patients without known coronary artery disease (CAD) who were clinically referred for ETT and CTA within 6 months. Patients were followed for cardiovascular (CV) death, non-fatal myocardial infarction (MI), or late revascularization (>90 days), stratified by Duke Treadmill Score (DTS) and CAD severity (≥50% stenosis). Mean age was 54 ± 13 years (63% male). In median follow-up of 40 months, there were 3 CV deaths, 7 non-fatal MIs, and 26 late revascularizations. ETT was inconclusive in 23%, positive in 31%, and negative in 46%. CTA demonstrated no CAD in 37%, non-obstructive CAD in 28%, and obstructive CAD in 35%. Among low-risk ETT patients (n = 326), there were 3 MI, 10 late revascularizations, and the frequent presence of non-obstructive (32%, n = 105) and obstructive CAD (27%, n = 88). When present, ETT features (i.e., angina, DTS, ischaemic electrocardiogram changes, and exercise capacity) individually failed to predict CV death/MI after adjustment for Morise score. Conversely, both obstructive CAD [HR 4.9 (1.0-23.3), P = 0.048] and CAD extent by segment involvement score >4 [HR 3.9 (1.0-15.2), P = 0.049] predicted increased risk for CV death or MI.

CONCLUSION

Patients with a low-risk ETT have an excellent prognosis at 40 months, despite the frequent presence of non-obstructive (32%) and obstructive (27%) CAD. In patients with an intermediate- to high-risk ETT (DTS <5), CTA can provide incremental risk stratification for future CV events.

Incidental extracardiac findings on cardiac MR: Systematic review and meta-analysis

PURPOSE

To perform a systematic review and meta-analysis to calculate the pooled prevalence of incidental extracardiac findings (IEFs) on cardiac magnetic resonance (MR) and to determine factors influencing reported prevalences.

MATERIALS AND METHODS

We examined studies published in the literature using the MEDLINE database. Studies reporting IEFs on cardiac MR were included. Meta-analysis provided pooled prevalences of total, minor, major IEFs, and major IEFs with patient management changes using a random-effects model. Heterogeneity and inconsistency (I-squared) between studies as well as publication bias were assessed.

RESULTS

Twelve studies including 7062 patients (mean age: 52 years, range: 0.5-93 years, 4476 male/2586 female) and 7122 cardiac MR examinations were considered in the meta-analysis. Overall, the pooled prevalence of total IEFs was 35% (95% confidence interval [CI]: 23-47%). The pooled prevalence of minor and major IEFs were 17% (95% CI: 9-26%) and 12% (95% CI: 7-18%), respectively. Newly diagnosed major IEFs changed patient management in 1% (95% CI: 1-2%) of the study population. A high heterogeneity and inconsistency (I-squared >74%) between studies without publication bias were observed, notably due to IEFs recording method (P < 0.002) and formal training of cardiac MR readers (P < 0.006).

CONCLUSION

Major IEFs may be found in 12% of patients undergoing cardiac MR examination and change the management in 1% of patients. Readers' training for the evaluation of noncardiac structures increases reported prevalence.

Collateral non cardiac findings in clinical routine CT coronary angiography: results from a multi-center registry

PURPOSE

The aim of the study was to evaluate the prevalence of collateral findings detected in computed tomography coronary angiography (CTCA) in a multi-center registry.

MATERIALS AND METHODS

We performed a retrospective review of 4303 patients (2719 males, mean age 60.3 ± 10.2 years) undergoing 64-slice CTCA for suspected or known coronary artery disease (CAD) at various academic institutions between 01/2006 and 09/2010. Collateral findings were recorded and scored as: non-significant (no signs of relevant pathology, not necessary to be reported), significant (clear signs of pathology, mandatory to be reported), or major (remarkable pathology, mandatory to be reported and further investigated).

RESULTS

We detected 6886 non-cardiac findings (1.6 non cardiac finding per patient). Considering all centers, only 865/4303 (20.1 %) patients were completely without any additional finding. Overall, 2095 (30.4 %) non-significant, 4486 (65.2 %) significant, and 305 (4.4 %) major findings were detected. Among major findings, primary lung cancer was reported in 21 cases. In every center, most prevalent significant findings were mediastinal lymph nodes >1 cm. In 256 patients, collateral findings were clinically more relevant than coexisting CAD and justified the symptoms of patients.

CONCLUSIONS

The prevalence of significant and major collateral findings in CTCA is high. Radiologists should carefully evaluate the entire scan volume in each patient.

Two-year survival of patients screened for transcatheter aortic valve replacement with potentially malignant incidental findings in initial body computed tomography

Aims

Recently, transcatheter aortic valve replacement (TAVR) has evolved as the standard treatment in patients with inoperable aortic valve stenosis. According to TAVR guidelines, body computed tomography (CT) is recommended for pre-procedural planning. Due to the advanced age of these patients, multiple radiological potentially malignant incidental findings (pmIFs) appear in this cohort. It is unknown how pmIFs influence the decision by the heart team to intervene and the mortality.

Methods and results

We evaluated in a retrospective single-centre observational study 414 participants screened for TAVR with dual-source CT between October 2010 and December 2012. pmIFs are common and appeared in 18.7% of all patients screened for TAVR. The decision to intervene by TAVR or surgical aortic valve replacement (SAVR) was made by an interdisciplinary heart team and the role of pmIF in decision-making and time to treatment with TAVR or SAVR was analysed, retrospectively. The appearance of a pmIF vs. no pmIF did not significantly influence therapeutic decisions [odds ratio (OR) 1.14; P = 0.835] or time to treatment (91 ± 152 vs. 61 ± 109 days, respectively). Several findings, which are highly suspicious for malignancy, were less likely associated with invasive treatment (OR 0.207; P = 0.046). Patient survival was evaluated for at least 2 years until January 2014. Two-year survival of patients after TAVR or SAVR, treated according to the heart team decision, was ∼75% and independent from the presence of a non-severe (P = 0.923) or severe (P = 0.823) pmIF.

Conclusion

The study indicates that frequently occurring radiologic pmIF did not influence 2-year survival after a decision to intervene was made by an interdisciplinary heart team.

Imaging-based screening: understanding the controversies

OBJECTIVE

The goals of this article are to provide an overview of controversial aspects of imaging-based screening and to elucidate potential risks that may offset anticipated benefits.

CONCLUSION

Current controversial topics associated with imaging-based screening include false-positive results, incidental findings, overdiagnosis, radiation risks, and costs. Alongside the benefits of screening, radiologists should be prepared to discuss these additional diagnostic consequences with providers and patients to better guide shared decision making regarding imaging-based screening.

Coronary computed tomographic angiography in the emergency room: state of the art

Chest pain is a common complaint in the emergency department often necessitating testing to exclude underlying obstructive coronary artery disease. While the traditional evaluation of patients with suspected acute coronary syndrome often consists of serial electrocardiograms and cardiac biomarkers, followed by selective use of stress testing for further risk stratification, this approach is costly and inefficient. Recently, coronary computed tomographic angiography (CTA) has offered an alternative approach with a high sensitivity and negative predictive value to exclude obstructive coronary artery disease that can rapidly identify patients with low rates of downstream major adverse cardiac events. In this review, the authors provide an overview of available data on the use of CTA for evaluating acute chest pain, while emphasizing its advantages and disadvantages compared to existing strategies. In addition, we provide a suggested algorithm to identify how CTA can be incorporated into the evaluation of acute chest pain and discuss tips for successful implementation of CTA in the emergency department.