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Sandeep S Hedgire,1 Mari Mino-Kenudson,2 Azadeh Elmi,1 Sarah Thayer,3 Carlos Fernandez-del Castillo,3 Mukesh G Harisinghani11Department of Abdominal Imaging and Intervention, 2Department of Pathology, 3Department of Surgery, Massachusetts General Hospital, Boston, MA, USAPurpose: To evaluate the role of ferumoxytol-enhanced magnetic resonance imaging (MRI) in delineating primary pancreatic tumors in patients undergoing preoperative neoadjuvant therapy.Materials and methods: Eight patients with pancreatic adenocarcinoma were enrolled in this study, and underwent MRI scans at baseline, immediate post, and at the 48 hour time point after ferumoxytol injection with quantitative T2* sequences. The patients were categorized into two groups; group A received preoperative neoadjuvant therapy and group B did not. The T2* of the primary pancreatic tumor and adjacent parenchyma was recorded at baseline and the 48 hour time point. After surgery, the primary tumors were assessed histopathologically for fibrosis and inflammation.Results: The mean T2* of the primary tumor and adjacent parenchyma at 48 hours in group A were 22.11 ms and 16.34 ms, respectively; in group B, these values were 23.96 ms and 23.26 ms, respectively. The T2* difference between the tumor and adjacent parenchyma in group A was more pronounced compared to in group B. The tumor margins were subjectively more distinct in group A compared to group B. Histopathologic evaluation showed a rim of dense fibrosis with atrophic acini at the periphery of the lesion in group A. Conversely, intact tumor cells/glands were present at the periphery of the tumor in group B.Conclusion: Ferumoxytol-enhanced MRI scans in patients receiving preoperative neoadjuvant therapy may offer enhanced primary tumor delineation, contributing towards achieving disease-free margin at the time of surgery, and thus improving the prognosis of pancreatic carcinomas.Keywords: pancreatic cancer, tumor margin, neoadjuvant therapy, borderline resectable pancreatic cancer

Sandeep S Hedgire,1 Shaunagh McDermott,1 Gregory R Wojtkiewicz,1 Seyed Mahdi Abtahi,1 Mukesh Harisinghani,1 Jason L Gaglia21Center for Systems Biology, Massachusetts General Hospital, Richard B Simches Research Center, 2Joslin Diabetes Center, Boston, MA, USAPurpose: To evaluate the time-dependent changes in regional quantitative T2* maps of the kidney following intravenous administration of ferumoxytol.Materials and methods: Twenty-four individuals with normal kidney function underwent T2*-weighted MRI of the kidney before, immediately after, and 48 hours after intravenous administration of ferumoxytol at a dose of 4 mg/kg (group A, n=12) or 6 mg/kg (group B, n=12). T2* values were statistically analyzed using two-tailed paired t-tests.Results: In group A, the percentage changes from baseline to immediate post and baseline to 48 hours were 85.3% and 64.2% for the cortex and 90.8% and 64.6% for the medulla, respectively. In group B, the percentage changes from baseline to immediate post and baseline to 48 hours were 85.2% and 73.4% for the cortex and 94.5% and 74% for the medulla, respectively. This difference was significant for both groups (P

Bronchial artery embolization may be the only life-saving procedure available in a patient presenting with massive hemoptysis. Rarely, selective catheterization of these vessels may be rendered difficult due to a stenotic ostium. This may result in closure of the vessel or absence of forward flow after the stenotic segment is crossed with a diagnostic catheter or a microcatheter. Further, it may also lead to recurrence of hemoptysis if the distal vessel and the prearteriolar bed are inadequately embolized. We describe a technique of selective cannulation of the stenotic vessel, dilatation of the stenosis and then successful embolization.

Purpose This special report outlines a retrospective observational study of CT fractional flow reserve (CT-FFR) analysis using dual-source coronary CT angiography (CTA) scans performed without heart rate control and its impact on clinical outcomes. Materials and Methods All patients who underwent clinically indicated coronary CTA between August 2020 and August 2021 were included in this retrospective observational study. Scans were performed in the late systolic to early diastolic period without heart rate control and analyzed at the interpreting physician's discretion. Demographics, coronary CTA features, and rates of invasive coronary angiography (ICA), percutaneous coronary intervention (PCI), myocardial infarction, and all-cause death at 3 months were assessed by chart review. Results During the study period, 3098 patients underwent coronary CTA, of whom 113 with coronary bypass grafting were excluded. Of the remaining 2985 patients, 292 (9.7%) were referred for CT-FFR analysis. Two studies (0.7%) were rejected from CT-FFR analysis, and six (2.1%) analyses did not evaluate the lesion of concern. A total of 160 patients (56.3%) had CT-FFR greater than 0.80. Among patients with significant stenosis at coronary CTA, patients who underwent CT-FFR analysis presented with lower rates of ICA (74.5% vs 25.5%, P = .04) and PCI (78.9% vs 21.1%, P = .05). Conclusion CT-FFR was implemented in patients not requiring heart rate control by using dual-source coronary CTA acquisition and showed the potential to decrease rates of ICA and PCI without compromising safety in patients with significant stenosis and an average heart rate of 65 beats per minute. Keywords: Angiography, CT, CT-Angiography, Fractional Flow Reserve, Cardiac, Heart, Arteriosclerosis Supplemental material is available for this article. © RSNA, 2024.

Background: Type 2 myocardial infarction (MI) results from coronary supply and demand imbalance and has a poor prognosis. It is crucial to identify potential sex-based differences in the prevalence and nature of coronary artery disease (CAD) within this population., Objectives: The purpose of this study was to evaluate sex-based disease differences in type 2 MI among patients evaluated with coronary computed tomography angiography and fractional flow reserve., Methods: In a single-center, prospective study, patients with strictly adjudicated type 2 MI underwent coronary computed tomography angiography with fractional flow reserve., Results: Among 50 study participants enrolled, 50% were women. A similar mix of MI precipitants was present in both sexes. ST-segment depression was more common in women (64% vs 32%), while men were more likely to have T wave inversion (68% vs 36%). Women and men had comparable coronary artery calcium scores (median: 152 [Q1, Q3: 45, 762] vs 234 [Q1, Q3: 56, 422]). Prevalence of any CAD (84% vs 100%), obstructive CAD (24% vs 28%), and hemodynamically significant focal stenosis (20% vs 32%) were similar between sexes. Total plaque volume was similar between sexes, but women had significantly lower levels of low-attenuation plaque (median: 3 [Q1, Q3: 1, 7] vs 9 [Q1, Q3: 3, 14])., Conclusions: Among patients with type 2 MI, prevalence of any CAD and obstructive CAD did not differ according to sex. Total plaque volume was similar between sexes, but women had a lower volume of low-attenuation plaque (DEFINing the PrEvalence and Characteristics of Coronary Artery Disease Among Patients With TYPE 2 Myocardial Infarction Using CT-FFR [DEFINE TYPE2MI]; NCT04864119)., Competing Interests: Dr Wasfy is supported by 10.13039/100000968American Heart Association (18 CDA 34110215); is chair of the New England Comparative Effectiveness Public Affairs Council (CEPAC); has received grant support from the American Heart Association and the National Institutes of Health; and has received past consulting fees from Pfizer and Biotronik. Dr Januzzi is supported by the Hutter Family Professorship. Dr McCarthy has received consulting income from Abbott Laboratories and Roche Diagnostics. Dr Ghoshhajra is on the Executive Committee of the Society of Cardiovascular Computed Tomography (President); has received grant support from 10.13039/501100011699Siemens Healthineers and the 10.13039/100000002National Institutes of Health; and received consulting fees from Siemens Healthineers, Philips Healthcare, and 3DR Labs (all unrelated to this work). Dr Rogers is an employee and shareholder of HeartFlow, Inc. Dr Blankstein has received research support from 10.13039/100002429Amgen Inc and 10.13039/100004336Novartis Inc; and has served as a consultant/advisory board for Caristo Inc, Elucid Inc, Hearflow Inc, Beren Therapeutics, Nanox AI. Dr Januzzi is a Trustee of the American College of Cardiology; a Director at Imbria Pharmaceuticals; an Advisor at Jana Care; has received grant support from 10.13039/100001316Abbott, Applied Therapeutics, 10.13039/100020588HeartFlow Inc, Innolife, and 10.13039/100016545Roche Diagnostics; consulting income from Abbott, Janssen, Novartis, Merck, and Roche Diagnostics; and participates in clinical endpoint committees/data safety monitoring boards for Abbott, AbbVie, Bayer, CVRx, Intercept, Pfizer, and Takeda. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2024 The Authors.)

Background: Type 2 myocardial infarction (T2MI) related to a supply/demand imbalance of coronary blood flow is common and associated with poor prognosis. Coronary artery disease (CAD) may predispose some individuals to T2MI and contribute to its high rate of recurrent cardiovascular events. Little is known about the presence and extent of CAD in this population., Objectives: The goal of this study was to evaluate the presence and characteristics of CAD among patients with T2MI., Methods: In this prospective study, consecutive eligible individuals with Fourth Universal Definition of Myocardial Infarction criteria for T2MI were enrolled. Participants underwent coronary computed tomography angiography (CTA), fractional flow reserve derived with coronary CTA (FFR CT ), and plaque volume analyses., Results: Among 50 participants, 25 (50%) were female, and the mean age was 68.0 ± 11.4 years. Atherosclerotic risk factors were common. Coronary CTA revealed coronary plaque in 46 participants (92%). A moderate or greater stenosis (≥50%) was identified in 42% of participants, and obstructive disease (≥50% left main stenosis or ≥70% stenosis in any other epicardial coronary artery) was present in 26%. Prevalence of obstructive CAD did not differ according to T2MI cause (P = 0.54). A hemodynamically significant focal stenosis identified by FFR CT was present in 13 participants (26%). Among participants with a stenosis ≥50% (n = 21), FFR CT excluded lesion-specific hemodynamically significant stenosis in 8 cases (38%)., Conclusions: Among individuals with adjudicated T2MI, CAD was prevalent, but the majority of patients had nonobstructive CAD. Mediators of ischemia are likely multifactorial in this population. (Defining the Prevalence and Characteristics of Coronary Artery Disease Among Patients with Type 2 Myocardial Infarction using CT-FFR [DEFINE TYPE 2 MI]; NCT04864119)., Competing Interests: Funding Support and Author Disclosures This work was supported by a grant from HeartFlow Inc. Dr McCarthy was supported by a National Heart, Lung, and Blood Institute T32 postdoctoral training grant (5T32HL094301-12); and has received consulting income from Abbott Laboratories and Roche Diagnostics. Dr Mohebi is supported by the Barry Fellowship. Dr Wasfy is supported by the American Heart Association (18 CDA 34110215); is chair of the New England Comparative Effectiveness Public Affairs Council (CEPAC); has received grant support from the American Heart Association and the National Institutes of Health; and has received consulting fees from Pfizer and Biotronik. Dr Januzzi is supported by the Hutter Family Professorship; is a Trustee of the American College of Cardiology; is a Director at Imbria Pharmaceuticals; is an advisor at Jana Care; has received grant support from Abbott, Applied Therapeutics, HeartFlow Inc, Innolife, and Roche Diagnostics; has received consulting income from Abbott, Janssen, Novartis, Merck, and Roche Diagnostics; and participates in clinical endpoint committees/data safety monitoring boards for Abbott, AbbVie, Bayer, CVRx, Intercept, Pfizer, and Takeda. Dr Ghoshhajra is on the Executive Committee of the Society of Cardiovascular Computed Tomography (President); has received grant support from Siemens Healthineers and the National Institutes of Health; and has received consulting fees from Siemens Healthineers, Philips Healthcare, and 3DR Labs (all unrelated to this work). Dr Rogers is an employee and shareholder of HeartFlow Inc. Dr Blankstein has received research support from Amgen Inc and Novartis Inc; and has served as a consultant/advisory board member for Caristo Inc, Elucid Inc, HeartFlow Inc, Beren Therapeutics, and Nanox.AI. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2023 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Purpose: To describe the design and methodological approach of a multicenter, retrospective study to externally validate a clinical and imaging-based model for predicting the risk of late adverse events in patients with initially uncomplicated type B aortic dissection (uTBAD)., Materials and Methods: The Registry of Aortic Diseases to Model Adverse Events and Progression (ROADMAP) is a collaboration between 10 academic aortic centers in North America and Europe. Two centers have previously developed and internally validated a recently developed risk prediction model. Clinical and imaging data from eight ROADMAP centers will be used for external validation. Patients with uTBAD who survived the initial hospitalization between January 1, 2001, and December 31, 2013, with follow-up until 2020, will be retrospectively identified. Clinical and imaging data from the index hospitalization and all follow-up encounters will be collected at each center and transferred to the coordinating center for analysis. Baseline and follow-up CT scans will be evaluated by cardiovascular imaging experts using a standardized technique., Results: The primary end point is the occurrence of late adverse events, defined as aneurysm formation (≥6 cm), rapid expansion of the aorta (≥1 cm/y), fatal or nonfatal aortic rupture, new refractory pain, uncontrollable hypertension, and organ or limb malperfusion. The previously derived multivariable model will be externally validated by using Cox proportional hazards regression modeling., Conclusion: This study will show whether a recent clinical and imaging-based risk prediction model for patients with uTBAD can be generalized to a larger population, which is an important step toward individualized risk stratification and therapy. Keywords: CT Angiography, Vascular, Aorta, Dissection, Outcomes Analysis, Aortic Dissection, MRI, TEVAR© RSNA, 2022See also the commentary by Rajiah in this issue., Competing Interests: Disclosures of conflicts of interest: D.M. Research grant from the National Institute of Biomedical Imaging and Bioengineering (no. 5T32EB009035); consulting fees from Segmed; stock or stock options in Segmed; member of Radiology: Cardiothoracic Imaging trainee editorial board. M.J.W. Postdoctoral Fellowship Award (no. 18POST34030192) from the American Heart Association, payments to author’s institution; consulting fees from Segmed; payment from GLG, AlphaInsight, and Guidepoint for expert testimony; leadership or fiduciary role in the Society of Cardiovascular Computed Tomography, unpaid; stock or stock options in Segmed. V.L.T. Shareholder of Segmed stock or stock options. V.H. No relevant relationships. M.C. Postdoctoral Fellowship Award (no. 826389) from the American Heart Association; payment or honoraria from FASTeR as lecturer for research methodology course; owner of stock options in Arterys; employee of Arterys. K.H. Payment or honoraria from Sanofi Genzyme and Amicus for lectures, presentations, speakers bureaus, manuscript writing, or educational events; participation on a Data Safety Monitoring Board or Advisory Board for Sanofi Genzyme; associate editor for Radiology: Cardiothoracic Imaging. M.O. No relevant relationships. D.O.T. No relevant relationships. R.O.A. Consultant for Medtronic and EndoRon; member of the Society for Vascular Surgery (SVS) Diversity Equity and Inclusion Committee and council member of the SVS Young Surgeon Section; shareholder for EndoRon and Voythus. S.H. No relevant relationships. N.S.B. Radiological Society of North America Research Scholar Grant (no. RSCH1801); entitled to royalties related to licensure of intellectual property to Imbio; patents planned, issued, or pending for U.S. patent number 10,896,507, Techniques of Deformation Analysis for Quantification of Vascular Enlargement in Aneurysmal Disease. B.Y. Honoraria from seminar hosted by Medtronic. J.M.L. Honoraria from Cardiovascular Institute of Philadelphia. T.G.G. No relevant relationships. D.P. No relevant relationships. G.F. No relevant relationships. L.L. Participation on the Medtronic Thoracic Hostile Neck Club Advisory Board, Barcelona, December 20, 2021. R.H. No relevant relationships. H.A. No relevant relationships. A.E.S. Member of Radiology: Cardiothoracic Imaging editorial board. E.C. No relevant relationships. S.M.J.v.K. No relevant relationships. G.W.H.S. No relevant relationships. A.M.S. No relevant relationships. K.B. No relevant relationships. D.C.M. No relevant relationships. M.P.F. No relevant relationships. D.F. Deputy editor for Radiology: Cardiothoracic Imaging., (© 2022 by the Radiological Society of North America, Inc.)

Purpose: To develop and validate a deep learning-based system that predicts the largest ascending and descending aortic diameters at chest CT through automatic thoracic aortic segmentation and identifies aneurysms in each segment., Materials and Methods: In this retrospective study conducted from July 2019 to February 2021, a U-Net and a postprocessing algorithm for thoracic aortic segmentation and measurement were developed by using a dataset (dataset A) that included 315 CT studies split into training, hyperparameter-tuning, and testing sets. The U-Net and postprocessing algorithm were associated with a Digital Imaging and Communications in Medicine series filter and visualization interface and were further validated by using a dataset (dataset B) that included 1400 routine CT studies. In dataset B, system-predicted measurements were compared with annotations made by two independent readers as well as radiology reports to evaluate system performance., Results: In dataset B, the mean absolute error between the automatic and reader-measured diameters was equal to or less than 0.27 cm for both the ascending aorta and the descending aorta. The intraclass correlation coefficients (ICCs) were greater than 0.80 for the ascending aorta and equal to or greater than 0.70 for the descending aorta, and the ICCs between readers were 0.91 (95% CI: 0.90, 0.92) and 0.82 (95% CI: 0.80, 0.84), respectively. Aneurysm detection accuracy was 88% (95% CI: 86, 90) and 81% (95% CI: 79, 83) compared with reader 1 and 90% (95% CI: 88, 91) and 82% (95% CI: 80, 84) compared with reader 2 for the ascending aorta and descending aorta, respectively., Conclusion: Thoracic aortic aneurysms were accurately predicted at CT by using deep learning. Keywords: Aorta, Convolutional Neural Network, Machine Learning, CT, Thorax, Aneurysms Supplemental material is available for this article .© RSNA, 2022., Competing Interests: Disclosures of conflicts of interest: F.B.C.M. Work was sponsored by Nuance Communications (Montreal, Quebec, Canada) who had a relationship with the institution in which this work was developed, but not directly with the co-authors from the Center for Clinical Data Science or from the MGH. C.L. Institutional support from NVIDIA, GE, and Nuance Communications. J.S. Work was performed while at the Center for Clinical Data Science and was sponsored by Nuance Communications. A.T. Nuance Communications sponsored MGH & BWH Center for Clinical Data Science (CCDS) to perform the study. Author collaborated with the study but didn’t have any financial benefit or interaction with Nuance Communications. R.B. Support from Nuance Communications; stock/stock options in Nuance Communications. S.D. Payments made to CCDS/Partners Healthcare from Nuance Communications. M.Y. Work was sponsored by Nuance Communications, who had a relationship with CCDS, but not directly to this author. V.B. Nuance Communications partly sponsored this work at the MGH & BWH Center of Clinical Data Science, where author was employed. Author did not have a direct relationship with Nuance. S.H. No relevant relationships. B.G. Grants/contracts from Siemens Healthineers and National Institutes of Health (unrelated to current work); support from Siemens Healthineers for attending meetings/travel (unrelated to current work); executive committee (treasurer) of Society of Cardiovascular Computed Tomography., (2022 by the Radiological Society of North America, Inc.)

Purpose: To perform a retrospective review of Coronary Artery Disease Reporting and Data System (CAD-RADS) adoption at a high-volume cardiac CT service., Materials and Methods: In this retrospective study, the adoption of CAD-RADS in 6562 coronary CT angiography (CTA) reports from January 1, 2017, to February 13, 2020, was evaluated. Reports without CAD-RADS were classified as opt-outs or exceptions to CAD-RADS. CAD-RADS classifications were retrospectively assigned to the opt-outs and the clinical indications for coronary CTA., Results: CAD-RADS scores were reported in 95% (6264 of 6562) of cases. Among the 5% ( n = 298) of reports not reported according to CAD-RADS, 58% ( n = 172) were considered opt-outs and 42% ( n = 126) were exceptions. Cases with higher degree of stenosis, stents, and coronary artery bypass grafts (CABGs) occurred more often in opt-outs versus reports with CAD-RADS (odds ratio [OR], 8.3 [95% CI: 1.6, 42.1]; P < .001). The quarterly opt-out rate decreased over consecutive quarters in the 1st year (OR, 0.77 [95% CI: 0.61, 0.96]; P = .01), then stabilized. Quarterly opt-out rate for patients with stents decreased over time (OR, 0.82 [95% CI: 0.73, 0.92]; P = .008), as did the opt-out rates in patients with CABG (OR, 0.83 [95% CI: 0.76, 0.91]; P < .001). Exceptions ( n = 126) included coronary dissections (44%), anomalous coronary arteries (41%), coronary artery aneurysms or pseudoaneurysms (10%), vasculitis (2%), stent complications (2%), and extrinsic compression of grafts (2%)., Conclusion: CAD-RADS was adopted rapidly and widely. Readers opted out of its use most often in complex cases of CAD, and the most common exceptions were coronary dissections and anomalous coronary artery. Keywords: Coronary Arteries, CT Angiography© RSNA, 2021., Competing Interests: Disclosures of Conflicts of Interest: A.K.T. disclosed no relevant relationships. V.T. disclosed no relevant relationships. R.J.G. disclosed no relevant relationships. J.D. disclosed no relevant relationships. S. Gupta disclosed no relevant relationships. S. Garrana Activities related to the present article: disclosed no relevant relationships. Activities not related to the present article: author receives author royalties from Elsevier, unrelated to this study. Other relationships: disclosed no relevant relationships. V.K. disclosed no relevant relationships. A.T.R. disclosed no relevant relationships. M.T.L. disclosed no relevant relationships. N.M. disclosed no relevant relationships. U.H. Activities related to the present article: disclosed no relevant relationships. Activities not related to the present article: author received consultancy fees from Recor and Duke University; author’s institution has grants/grants pending from KOWA, Astra Zeneca, Medimmune, and HeartFlow. Other relationships: disclosed no relevant relationships. S.H. disclosed no relevant relationships. B.G. Activities related to the present article: author’s institution has grant support from Siemens Healthineers for cardiac CT research unrelated to this work; author is on the editorial board of Radiology: Cardiothoracic Imaging (not involved in handling of the article). Activities not related to the present article: disclosed no relevant relationships. Other relationships: disclosed no relevant relationships., (2021 by the Radiological Society of North America, Inc.)

The aortic pathologies are well recognized on imaging. However, conventionally cardiac and proximal aortic abnormalities were only seen on dedicated cardiac or aortic studies due to need for ECG gating. Advances in CT technology have allowed motionless imaging of the chest and abdomen, leading to an increased visualization of cardiac and aortic root diseases on non-ECG-gated imaging. The advances are mostly driven by high pitch due to faster gantry rotation and table speed. The high-pitch scans are being increasingly used for variety of clinical indications because the images are free of motion artifact (both breathing and pulsation) as well as decreased radiation dose. Recognition of aortic root pathologies may be challenging due to lack of familiarity of radiologists with disease spectrum and their imaging appearance. It is important to recognize some of these conditions as early diagnosis and intervention is key to improving prognosis. We present a comprehensive review of proximal aortic anatomy, pathologies commonly seen at the aortic root, and their imaging appearances to familiarize radiologists with the diseases of this location.

Purpose: To determine the impact of low tube voltage coronary CT angiography on detection of subclinical atherosclerosis., Materials and Methods: Retrospective sampling of an emergency department coronary CT angiography registry was performed. All patients in the registry underwent a noncontrast coronary artery calcium (CAC) scoring scan at 120 kV before coronary CT angiography. The study sample ( n = 264) constituted patients with subclinical atherosclerosis (Coronary Artery Disease Reporting and Data System™ [CAD-RADS] 1 or 2) randomly mixed one-to-one with patients without atherosclerosis (CAD-RADS 0). The patients with coronary CT angiography performed at 70-90 kV were considered the low tube voltage group ( n = 159) and patients with coronary CT angiography performed at 100-120 kV were considered the standard tube voltage group ( n = 105). The number of coronary plaques and overall CAD-RADS classification (per patient) were evaluated twice: initially, by reading coronary CT angiography alone, and then, by coronary CT angiography in combination with a CAC scan. Considering the combined reading (CT angiography plus CAC scan) as the reference standard, the performance of coronary CT angiography alone was assessed for plaque detection and appropriate CAD-RADS (per patient) classification. The comparisons were made between the low tube voltage and standard tube voltage groups by using a Fisher exact test and χ 2 test for proportions and a Mann-Whitney test and Kruskal-Wallis test for means., Results: In total, 455 plaques were identified in 118 patients (70 of 159 patients in the low tube voltage group; 48 of 105 in the standard tube voltage group). When reading coronary CT angiographic images alone, 97 of 455 (21%) plaques were missed that led to an incorrect CAD-RADS classification in 16 of 264 (6%) studies (interpreted as CAD-RADS 0 instead of CAD-RADS 1 or 2). Missed plaques were significantly more frequent in the low tube voltage group versus the standard tube voltage group (41% [85 of 206] vs 5% [12 of 249], respectively; P < .001). Incorrect CAD-RADS classification was also seen more commonly in the low tube voltage group (8.8% [14 of 159] vs 2% [two of 105]; P = .01), typically at low plaque burden (median CAC score, 1; range, 1-4). Calcified plaques that appeared isodense to luminal contrast material attenuation were seen more frequently in the low tube voltage group compared with the standard tube voltage group (20% [32 of 159] vs 7.6% [eight of 105], respectively; P = .005)., Conclusion: Coronary artery plaques may be missed at low tube voltage coronary CT angiographic examination performed without a concomitant CAC scan.© RSNA, 2019 Supplemental material is available for this article. See also the commentary by Truong in this issue., Competing Interests: Disclosures of Conflicts of Interest: B.V. disclosed no relevant relationships. J.E.S. disclosed no relevant relationships. H.K. disclosed no relevant relationships. S.H. disclosed no relevant relationships. B.B.G. Activities related to the present article: disclosed no relevant relationships. Activities not related to the present article: institution receives grant from Siemens Healthcare (fellow salary support); author is paid by Medtronic (unrelated heart valve imaging) for development of educational presentations; shareholder in Apple; receives minor travel accommodations from Siemens Healthcare. Other relationships: disclosed no relevant relationships., (2019 by the Radiological Society of North America, Inc.)

Ultrasound (US) and Doppler are often the first imaging to be carried out for arterial disease, and with good reason. US is noninvasive, free of radiation exposure and crucial for follow up imaging. The review that follows aims to highlight the various applications of US in imaging of the arterial system., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Non-invasive cross-sectional imaging techniques play a crucial role in the assessment of the vascular disease processes. Computed tomography angiography (CTA) is an imaging method of choice for a wide range of vascular diseases that span across different vascular territories. A diagnostic quality CTA requires a robust imaging protocol tailored according to the physiologic state and vascular area of interest. This review article is aimed to provide an overview of the technical considerations and clinical applications of CTA., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Acute aortic syndrome (AAS) and emergencies are relatively uncommon but are considered as life threatening, potentially fatal conditions. Different forms of aortic emergencies/AAS are often clinically indiscernible. Prompt and accurate diagnosis of these entities significantly influences prognosis and guides therapy. We aim to elucidate the pertinent role that radiology plays in the management of acute aortic diseases, with contrast-enhanced computed tomography angiography (CTA) being the most rapid and robust imaging technique., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Considerable progress has been made in the management of diseases of the thoracic and abdominal aorta over the past decades, ranging from advances in open repair to the advent of minimally invasive endovascular techniques. Along with this comes an equivalent rise in imaging necessity for these patients, both in preoperative planning and postoperative surveillance. With the growing complexity and diversity of vascular procedures and techniques, it is essential to have a solid understanding of the imaging features and postoperative complications of these procedures to avoid imaging pitfalls. This review is an attempt to define the normal postoperative appearance and important complications of various open and endovascular surgical techniques of the thoracic and abdominal aorta., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Aim: To investigate feasibility of a quantitative study of prostate cancer using three dimensional (3D) fiber tractography., Methods: In this institutional review board approved retrospective study, 24 men with biopsy proven prostate cancer underwent prostate magnetic resonance imaging (MRI) with an endorectal coil on a 1.5 T MRI scanner. Single shot echo-planar diffusion weighted images were acquired with b = 0.600 s/mm(2), six gradient directions. Open-source available software TrackVis and its Diffusion Toolkit were used to generate diffusion tensor imaging (DTI) map and 3D fiber tracts. Multiple 3D spherical regions of interest were drawn over the areas of tumor and healthy prostatic parenchyma to measure tract density, apparent diffusion coefficient (ADC) and fractional anisotropy (FA), which were statistically analyzed., Results: DTI tractography showed rich fiber tract anatomy with tract heterogeneity. Mean tumor region and normal parenchymal tract densities were 2.53 and 3.37 respectively (P < 0.001). In the tumor, mean ADC was 0.0011 × 10(-3) mm(2)/s vs 0.0014 × 10(-3) mm(2)/s in the normal parenchyma (P < 0.001). The FA values for tumor and normal parenchyma were 0.2047 and 0.2259 respectively (P = 0.3819)., Conclusion: DTI tractography of the prostate is feasible and depicts congregate fibers within the gland. Tract density may offer new biomarker to distinguish tumor from normal tissue.

The inability to visualize the initiation and progression of type-1 diabetes (T1D) noninvasively in humans is a major research and clinical stumbling block. We describe an advanced, exportable method for imaging the pancreatic inflammation underlying T1D, based on MRI of the clinically approved magnetic nanoparticle (MNP) ferumoxytol. The MNP-MRI approach, which reflects nanoparticle uptake by macrophages in the inflamed pancreatic lesion, has been validated extensively in mouse models of T1D and in a pilot human study. The methodological advances reported here were enabled by extensive optimization of image acquisition at 3T, as well as by the development of improved MRI registration and visualization technologies. A proof-of-principle study on patients recently diagnosed with T1D versus healthy controls yielded two major findings: First, there was a clear difference in whole-pancreas nanoparticle accumulation in patients and controls; second, the patients with T1D exhibited pronounced inter- and intrapancreatic heterogeneity in signal intensity. The ability to generate noninvasive, 3D, high-resolution maps of pancreatic inflammation in autoimmune diabetes should prove invaluable in assessing disease initiation and progression and as an indicator of response to emerging therapies.