The Contemporary Role of Cardiac Computed Tomography and Cardiac Magnetic Resonance Imaging in the Diagnosis and Management of Pericardial Diseases.

Pericardial syndromes encompass different clinical conditions from acute pericarditis to idiopathic chronic pericardial effusion. Transthoracic echocardiography is the first and most important initial diagnostic imaging modality in most patients affected by pericardial disease. However, cardiac computed tomography (CCT) and cardiac magnetic resonance imaging (CMR) have recently gained a pivotal role in cardiology, and recent reports have supported the role of both of these advanced techniques in the evaluation and guiding therapy of pericardial disease. Most promising is the capability of CMR to identify the presence of pericardial inflammation, carrying both diagnostic and prognostic value in the setting of recurrent and chronic pericarditis. In addition, CCT permits accurate evaluation of the presence and extension of pericardial calcification, providing important information in confirming the diagnosis of constrictive pericarditis and during the preprocedural planning for patients undergoing pericardiectomy. Both CCT and CMR require specific expertise, especially for the evaluation of pericardial disease. The aim of the present review is to provide physicians an updated overview of CCT and CMR in pericardial disease, focusing on technical issues, recent research findings, and potential clinical applications.

Lung ultrasound in the follow-up of severe COVID-19 pneumonia: six months evaluation and comparison with CT.

While lung ultrasonography (LUS) proved to be a useful diagnostic and prognostic tool in acute phase of COVID 19 pneumonia, its role in detecting long-term pulmonary sequelae has yet to be explored. In our prospective observational study we assessed the potential of LUS in detecting the presence of computed tomography (CT) fibrotic-like changes after 6 months from COVID-19 pneumonia. Patients who were discharged with a diagnosis of severe COVID-19 pneumonia were enrolled. After 6 months from hospital discharge they underwent LUS, chest CT scan and pulmonary function tests. A logistic regression analysis was performed to assess the association between presence of symptoms, LUS score and diffusing capacity for carbon monoxide (DLCO) at 6-month after hospital discharge and CT scan fibrotic-like changes. A second logistic model was performed to assess the value of some predefined baseline factors (age, sex, worst PaO2/FiO2, ventilator support, worst CRP value, worst D-dimer value and worst LUS score during hospitalization) to predict fibrotic-like changes on 6-month CT scan. Seventy-four patients were enrolled in the study. Twenty-four (32%) showed lung abnormalities suitable for fibrotic-like changes. At multivariate logistic regression analysis LUS score after 6 months from acute disease was significantly associated with fibrotic-like pattern on CT scan. The second logistic model showed that D-dimer value was the only baseline predictive variable of fibrotic-like changes at multivariate analysis. LUS performed after 6 months from severe COVID-19 pneumonia may be a promising tool for detection and follow-up of pulmonary fibrotic sequelae.

Clinical-radiological correlations in COVID-19-related venous thromboembolism: Preliminary results from a multidisciplinary study.

INTRODUCTION: Among the multiple complex pathophysiological mechanisms underlying COVID-19 pneumonia, immunothrombosis has been shown to play a key role. One of the most dangerous consequences of the prothrombotic imbalance is the increased incidence of micro- and macrothrombotic phenomena, especially deep vein thrombosis (DVT) and pulmonary embolism (PE). METHODS: We investigated the correlation between radiological and clinical-biochemical characteristics in a cohort of hospitalised COVID-19 patients. RESULTS: PE was confirmed in 14/61 (23%) patients, five (35.7%) had DVT. The radiographic findings, quantified by Qanadli score calculated on CT angiography, correlated with the clinical score and biochemical markers. The ratio between the right and left ventricle diameter measured at CT angiography correlated with the length of hospital stay. CONCLUSION: In our cohort radiological parameters showed a significant correlation with clinical prognostic indices and scores, thus suggesting that a multidisciplinary approach is advisable in the evaluation of PE in COVID-19 patients.

Trends over Time of Lung Function and Radiological Abnormalities in COVID-19 Pneumonia: A Prospective, Observational, Cohort Study.

Radiological and functional sequelae of Coronavirus Disease 2019 (COVID-19) pneumonia are still poorly understood. This was a prospective, observational, physiological, cohort study on consecutive adult patients with COVID-19 pneumonia admitted in April-May 2020 in the high dependency respiratory unit of L. Sacco University Hospital in Milan (Italy). During hospitalization, patients underwent chest computed tomography (CT), blood gas analysis, spirometry, and lung diffusion capacity for carbon monoxide (DLco), which were repeated 6 weeks post-discharge. Chest CTs were individually read by two expert radiologists, that calculated the total severity score (TSS). Twenty patients completed the study (mean age 58.2 years, 70% males). During the acute phase, mean DLco, alveolar volume (VA), and vital capacity (VC) were 56.0 (16.3), 64.8 (14.0), and 71.7 (16.9) % predicted, respectively, and were inversely associated with PaO2/FiO2 ratio. Fifty percent of patients had a restrictive ventilatory pattern; mean TSS was 7.9 (4.0). At follow up, gas exchange parameters were normalized; consolidations persisted in 10% of cases, while DLco was <80% predicted in 65% of patients and was independently predicted by Log10D-dimer at admission (ß -18.675; 95%CI, -28.373--9.076; p = 0.001). In conclusion, functional abnormalities in COVID-19 pneumonia survivors can persist during follow up and are associated with the severity of the disease.

Image-Based Computational Hemodynamics Analysis of Systolic Obstruction in Hypertrophic Cardiomyopathy.

Hypertrophic Cardiomyopathy (HCM) is a pathological condition characterized by an abnormal thickening of the myocardium. When affecting the medio-basal portion of the septum, it is named Hypertrophic Obstructive Cardiomyopathy (HOCM) because it induces a flow obstruction in the left ventricular outflow tract. In any type of HCM, the myocardial function can become compromised, possibly resulting in cardiac death. In this study, we investigated with computational analysis the hemodynamics of patients with different types of HCM. The aim was quantifying the effects of this pathology on the intraventricular blood flow and pressure gradients, and providing information potentially useful to guide the indication and the modality of the surgical treatment (septal myectomy). We employed an image-based computational approach, integrating fluid dynamics simulations with geometric and functional data, reconstructed from standard cardiac cine-MRI acquisitions. We showed that with our approach we can better understand the patho-physiological behavior of intraventricular blood flow dynamics due to the abnormal morphological and functional aspect of the left ventricle. The main results of our investigation are: (a) a detailed patient-specific analysis of the blood velocity, pressure and stress distribution associated to HCM; (b) a computation-based classification of patients affected by HCM that can complement the current clinical guidelines for the diagnosis and treatment of HOCM.

Chest X-ray findings in a large cohort of 1117 patients with SARS-CoV-2 infection: a multicenter study during COVID-19 outbreak in Italy.

To describe radiographic key patterns on Chest X-ray (CXR) in patients with SARS-CoV-2 infection, assessing the prevalence of radiographic signs of interstitial pneumonia. To evaluate pattern variation between a baseline and a follow-up CXR. 1117 patients tested positive for SARS-CoV-2 infection were retrospectively enrolled from four centers in Lombardy region. All patients underwent a CXR at presentation. Follow-up CXR was performed when clinically indicated. Two radiologists in each center reviewed images and classified them as suggestive or not for interstitial pneumonia, recording the presence of ground-glass opacity (GGO), reticular pattern or consolidation and their distribution. Pearson's χ2 test for categorical variables and McNemar test (χ2 for paired data) were performed. Patients mean age 63.3 years, 767 were males (65.5%). The main result is the large proportion of positive CXR in COVID-19 patients. Baseline CXR was positive in 940 patients (80.3%), with significant differences in age and sex distribution between patients with positive and negative CXR. 382 patients underwent a follow-up CXR. The most frequent pattern on baseline CXR was the GGO (66.1%), on follow-up was consolidation (53.4%). The most common distributions were peripheral and middle-lower lung zone. We described key-patterns and their distribution on CXR in a large cohort of COVID-19 patients: GGO was the most frequent finding on baseline CXR, while we found an increase in the proportion of lung consolidation on follow-up CXR. CXR proved to be a reliable tool in our cohort obtaining positive results in 80.3% of the baseline cases.

Peripartum cardiomyopathy in a COVID-19-infected woman: differential diagnosis with acute myocarditis-A case report from a Hub Institution during the COVID-19 outbreak.

We report the case of a healthy 35-year-old woman who had experienced a flu-like syndrome during the week before childbirth and heart failure symptoms 10 days before the current hospitalization and presented to our emergency department with clinical signs of congestive heart failure, echocardiographic evidence of a severely dilated and hypokinetic heart, laboratory evidence of SARS-CoV-2 disease, and radiologic findings consistent with both virus-related pneumonia and heart failure. Early cardiac magnetic resonance was crucial for the diagnosis of postpartum cardiomyopathy and for the exclusion of virus-related myocarditis, allowing us to decide on a prudent and supportive clinical approach.

An image-based computational hemodynamics study of the Systolic Anterior Motion of the mitral valve.

Systolic Anterior Motion (SAM) of the mitral valve - often associated with Hypertrophic Obstructive Cardiomyopathy (HOCM) - is a cardiac pathology in which a functional subaortic stenosis is induced during systole by the mitral leaflets partially obstructing the outflow tract of the left ventricle. Its assessment by diagnostic tests is often difficult, possibly underestimating its severity and thus increasing the risk of heart failure. In this paper, we propose a new computational pipeline, based on cardiac cine Magnetic Resonance Imaging (cine-MRI) data, for the assessment of SAM. The pipeline encompasses image processing of the left ventricle and the mitral valve, and numerical investigation of cardiac hemodynamics by means of Computational Fluid Dynamics (CFD) in a moving domain with image-based prescribed displacement. Patient-specific geometry and motion of the left ventricle are considered in view of an Arbitrary Lagrangian-Eulerian approach for CFD, while the reconstructed mitral valve is immersed in the computational domain by means of a resistive method. We assess clinically relevant flow and pressure indicators in a parametric study for different degrees of SAM severity, in order to provide a better quantitative evaluation of the pathological condition. Moreover, we provide specific indications for its possible surgical treatment, i.e. septal myectomy.

Myocardial edema in paroxysmal permeability disorders: The paradigm of Clarkson's disease.

PURPOSE: Paroxysmal Permeability Disorders (PPDs) comprise a variety of diseases characterized by recurrent and transitory increase of endothelial permeability. Idiopathic Systemic Capillary Leak Syndrome (ISCLS) is a rare PPD that leads to an abrupt massive shift of fluids and proteins from the intravascular to the interstitial compartment. In some cases, tissue edema may involve the myocardium, but its role in the development of shock has not been elucidated so far. MATERIALS AND METHODS: Assessment of cardiac involvement during ten life-threatening ISCLS episodes admitted to ICU. RESULTS: Transthoracic echocardiographic examination was performed in eight episodes, whereas a poor acoustic window prevented cardiac ultrasound assessment in two episodes. Myocardial edema was detected by echocardiography in eight episodes and marked pericardial effusion in one-episode. Cardiac magnetic resonance showed diffuse myocardial edema in another episode. In one case, myocardial edema caused fulminant left ventricular dysfunction, which required extracorporeal life support. The mean septum thickness was higher during the shock phase compared to the recovery phase [15.5 mm (13.1-21 mm) vs. 9.9 mm (9-11.3 mm), p = .0003]. Myocardial edema resolved within 72 h. CONCLUSIONS: During early phases of ISCLS, myocardial edema commonly occurs and can induce transient myocardial dysfunction, potentially contributing to the pathogenesis of shock.

Imaging the operated colon using water-enema multidetector CT, with emphasis on surgical anastomoses.

Water-enema multidetector CT (WE-MDCT) provides a detailed multiplanar visualisation of mural, intra- and extraluminal abnormalities of the large bowel, relying on preliminary bowel cleansing, retrograde luminal distension, pharmacological hypotonisation and intravenous contrast enhancement. In patients with a history of colorectal surgery for either carcinoma or Crohn's disease (CD), WE-MDCT may also be performed via a colostomy, which allows depicting the anatomy and position of the residual large bowel and evaluates the calibre, length, mural and extraluminal features of luminal strictures. Therefore, WE-MDCT may prove useful as a complementary technique after incomplete or inconclusive colonoscopy to assess features and suspected abnormalities of the surgical anastomosis, particularly when endoscopic or surgical interventions are being planned. This pictorial essay presents the WE-MDCT technique and pitfalls, the expected appearances after different colic surgeries and the imaging features of benign anastomotic disorders (fibrotic stricture, kinking, inflammatory ulcer) and of locally recurrent tumours and CD. TEACHING POINTS: • Water-enema multidetector CT (WE-MDCT) effectively visualises the operated colon • Complementary to endoscopy, WE-MDCT may helpfully depict abnormalities of surgical anastomoses • WE-MDCT allows assessment of strictures' features and abnormalities of the upstream bowel • Technical pitfalls, normal postsurgical findings and benign anastomotic disorders are presented • WE-MDCT allows detecting relapsing Crohn's disease, recurrent and metachronous tumours.

A computational fluid-structure interaction analysis of coronary Y-grafts.

Coronary artery disease is one of the leading causes of death worldwide. The stenotic coronary vessels are generally treated with coronary artery bypass grafts (CABGs), which can be either arterial (internal mammary artery, radial artery) or venous (saphenous vein). However, the different mechanical properties of the graft can influence the outcome of the procedure in terms of risk of restenosis and subsequent graft failure. In this paper, we perform a computational fluid-structure interaction (FSI) analysis of patient-specific multiple CABGs (Y-grafts) with the aim of better understanding the influence of the choice of bypass (arterial vs venous) on the risk of graft failure. Our results show that the use of a venous bypass results in a more disturbed flow field at the anastomosis and in higher stresses in the vessel wall with respect to the arterial one. This could explain the better long-term patency of the arterial bypasses experienced in the clinical practice.

Preoperative Computed Tomography Scan Analysis of Interleaflets Triangles to Guide Aortic Root Repair Procedures.

BACKGROUND: Stabilization of the ventriculo-aortic junction (VAJ) is gaining increasing interest in the context of aortic valve repair, since its dilation is a well-recognized risk factor for long-term repair failure. Interleaflets triangles are key elements of the VAJ, but cannot be completely visualized using echocardiography. A three-dimensional (3D) reconstruction of electrocardiogram-triggered computed tomography (CT) scan images allows an analysis of the real dimensions and anatomic characteristics of the subcommissural triangles. METHODS: A method was developed to visualize the interleaflets triangle at the CT-scan based on multiplanar post-processing reconstructions. Attention was focused on the triangles' apical angle evaluation. The data obtained with CT-scan reconstructions were compared with those collected in a previous post-mortem study to validate this measurement method. RESULTS: In the CT-scan group the angles between the left and right coronary sinuses, and the right non-coronary and left non-coronary sinuses were 46.23 ± 7.79°, 47.38 ± 6.97°, 45° [range: 42.75- 50.75°], respectively, and in the post-mortem group were 45.44 ± 12.39°, 48.31 ± 1218°, 50.25 ± 7.29°. No statistically significant differences between the two groups were identified (p = 0.84, 0.81, and 0.23). CONCLUSIONS: Based on experience acquired in the operating room, the acute-angle subcommissural triangles were considered normal, the equilateral triangles mildly dilated, and the obtuse triangles severely dilated. According to this classification, different reparative approaches were selected. A CTscan 3D reconstruction method, as validated by the present data, allows a preoperative evaluation of the triangles and VAJ in order to best plan a surgical reparative approach tailored to a single patient.

Numerical modeling of hemodynamics scenarios of patient-specific coronary artery bypass grafts.

A fast computational framework is devised to the study of several configurations of patient-specific coronary artery bypass grafts. This is especially useful to perform a sensitivity analysis of the hemodynamics for different flow conditions occurring in native coronary arteries and bypass grafts, the investigation of the progression of the coronary artery disease and the choice of the most appropriate surgical procedure. A complete pipeline, from the acquisition of patient-specific medical images to fast parameterized computational simulations, is proposed. Complex surgical configurations employed in the clinical practice, such as Y-grafts and sequential grafts, are studied. A virtual surgery platform based on model reduction of unsteady Navier-Stokes equations for blood dynamics is proposed to carry out sensitivity analyses in a very rapid and reliable way. A specialized geometrical parameterization is employed to compare the effect of stenosis and anastomosis variation on the outcome of the surgery in several relevant cases.

Computational study of the risk of restenosis in coronary bypasses.

Coronary artery disease, caused by the buildup of atherosclerotic plaques in the coronary vessel wall, is one of the leading causes of death in the world. For high-risk patients, coronary artery bypass graft is the preferred treatment. Despite overall excellent patency rates, bypasses may fail due to restenosis. In this context, the purpose of this work was to perform a parametric computational study of the fluid dynamics in patient-specific geometries with the aim of investigating a possible relationship between coronary stenosis degree and risk of graft failure. Firstly, we propose a strategy to prescribe realistic boundary conditions in the absence of measured data, based on an extension of Murray's law to provide the flow division at bifurcations in case of stenotic vessels and non-Newtonian blood rheology. Then, we carry out numerical simulations in three patients affected by severe coronary stenosis and treated with a graft, in which the stenosis degree is virtually varied in order to compare the resulting fluid dynamics in terms of hemodynamic indices potentially involved in restenosis development. Our findings suggest that low degrees of coronary stenosis produce a more disturbed fluid dynamics in the graft, resulting in hemodynamic conditions that may promote a higher risk of graft failure.

Cross-sectional imaging of complicated urinary infections affecting the lower tract and male genital organs.

Complicated urinary tract infections (C-UTIs) are those associated with structural or functional genitourinary abnormalities or with conditions that impair the host defence mechanisms, leading to an increased risk of acquiring infection or failing therapy. C-UTIs occur in patients with risk factors such as neurogenic dysfunction, bladder outlet obstruction, obstructive uropathy, bladder catheterisation, urologic instrumentation or indwelling stent, urinary tract post-surgical modifications, chemotherapy- or radiation-induced damage, renal impairment, diabetes and immunodeficiency.Multidetector CT and MRI allow comprehensive investigation of C-UTIs and systemic infection from an unknown source. Based upon personal experience at a tertiary care hospital focused on the treatment of infectious illnesses, this pictorial essay reviews with examples the clinical features and cross-sectional imaging findings of C-UTIs affecting the lower urinary tract and male genital organs. The disorders presented include acute infectious cystitis, bladder mural abscesses, infections of the prostate and seminal vesicles, acute urethritis and related perineal abscesses, funiculitis, epididymo-orchitis and scrotal abscesses. Emphasis is placed on the possible differential diagnoses of lower C-UTIs.The aim is to provide radiologists greater familiarity with these potentially severe disorders which frequently require intensive in-hospital antibiotic therapy, percutaneous drainage or surgery. Teaching Points • Complicated urinary tract infections occur in patients with structural or functional risk factors.• CT and MRI comprehensively investigate complicated urinary infections and sepsis from unknown sources.• Infections of the urinary bladder, prostate, seminal vesicles, urethra and scrotum are presented.• Emphasis is placed on differential diagnoses of complicated lower urogenital infections.• Unsuspected urinary infections may be detected on CT performed for other clinical reasons.

Multidetector CT of expected findings and early postoperative complications after current techniques for ventral hernia repair.

UNLABELLED: Current techniques for ventral hernia repair (VHR) rely on prosthetic mesh implantation and are increasingly performed laparoscopically. Potentially serious iatrogenic complications may occur following VHR, though these are rare compared to the vast number of procedures performed each year. This paper provides an overview of contemporary open and laparoscopic surgical techniques and biomaterials, then reviews and illustrates the expected postoperative imaging appearances, and common and unusual early complications after VHR. Emphasis is placed on multidetector computed tomography (CT), which comprehensively visualizes the operated anterior abdominal wall and deeper intra-abdominal structures. CT consistently allows diagnosis of postoperative seromas, abdominal wall abscesses and fistulas, haemorrhages with or without active bleeding, bowel obstruction, peritonitis and recurrent hernias, and thus providing a reliable basis for an appropriate choice between conservative, interventional, or surgical treatment. Familiarity with early post-surgical CT is warranted to avoid misinterpretation of the expected imaging appearance and correctly elucidate postoperative complications after VHR. TEACHING POINTS: • Open and laparoscopic repair of ventral hernias rely on prosthetic mesh implantation. • Potentially serious iatrogenic complications occasionally occur after ventral hernioplasty. • Multidetector CT consistently evaluates the operated abdominal wall and deeper structures. • Familiarity with the expected early postoperative imaging appearance is required. • Complications include seroma, infections, haemorrhage, bowel obstruction, peritonitis, and recurrence.

Pictorial review of normal postoperative cross-sectional imaging findings and infectious complications following laparoscopic appendectomy.

Laparoscopic appendectomy is increasingly accepted as the preferred surgical treatment for acute appendicitis and represents one of the most common emergency operations performed in both adult and paediatric populations. However, in patients with perforated appendicitis laparoscopy is associated with an increased incidence of postoperative intraabdominal infections compared to open appendectomy. Nowadays urgent imaging is commonly requested by surgeons when postoperative complications are suspected. Due to the widespread use of laparoscopy, in hospitals with active surgical practices clinicians and radiologists are increasingly faced with suspected postappendectomy complications. This pictorial essay illustrates the normal cross-sectional imaging findings observed shortly after laparoscopic appendectomy and the spectrum of appearances of iatrogenic intraabdominal infections observed in adults and adolescents, aiming to provide radiologists with an increased familiarity with early postoperative imaging. Emphasis is placed on the role of multidetector CT, which according to the most recent World Society of Emergency Surgery (WSES) guidelines is the preferred and most accurate modality to promptly investigate suspected intraabdominal infections and highly helpful for correct therapeutic choice, particularly to identify those occurrences that require in-hospital treatment, drainage or surgical reintervention. In teenagers and young adults MRI represents an attractive alternative modality to detect or exclude iatrogenic abscesses without ionising radiation. Teaching points • Laparoscopic appendectomy is the preferred surgical treatment for uncomplicated acute appendicitis • In perforated appendicitis laparoscopy results in increased incidence of intraabdominal infections • Multidetector CT promptly assesses suspected iatrogenic intraabdominal infections • Interpretation of early postoperative CT requires knowledge of normal postsurgical imaging findings • Postsurgical infections include right-sided peritonitis, intraabdominal, pelvic or liver abscesses.

Cross-sectional imaging of iatrogenic complications after extracorporeal and endourological treatment of urolithiasis.

Extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS) currently represent the mainstay treatment options for the vast majority of patients with urolithiasis, with limited contraindications and high success rates. However, minimally invasive extracorporeal and endourological treatments are associated with a non-negligible morbidity including occasional life-threatening occurrences. These complications represent a source of concern for urologists since they may result in prolonged hospitalisation, need for surgical, endoscopic or interventional treatment, long-term renal impairment, and sometimes even medical malpractice claims. Due to the increasing prevalence of urolithiasis and the large number of therapeutic procedures performed, in hospitals with active urologic practices radiologists are increasingly requested to investigate suspected post-procedural complications following ESWL, PCNL or ureteroscopic stone removal. Based upon our experience, this pictorial essay provides an overview of current extracorporeal and endourological treatment modalities for urolithiasis, including indications and possible complications according to the most recent guidelines from the European Association of Urology (EAU). Afterwards, we review the clinical features and cross-sectional imaging appearances of common and unusual complications with case examples, including steinstrasse, subcapsular, perirenal and suburothelial haemorrhages, severe urinary tract infections (such as pyeloureteritis, pyelonephritis, renal abscesses and pyonephrosis), ureteral injuries and delayed strictures. Teaching points • Extracorporeal lithotripsy, percutaneous nephrolitotomy and ureteroscopy allow treating urolithiasis. • Minimally invasive extracorporeal and endourological treatment have non-negligible morbidity. • Multidetector CT allows confident assessment of stone-free status and postprocedural complications. • Main complications include steinstrasse, bleeding, severe infections, ureteral injuries and strictures. • Imaging triage allows the choice among conservative, surgical, endoscopic or interventive treatment.