Publications by authors named "Demetrios A Raptis"

The Coronavirus Disease of 2019 (COVID-19) pandemic has caused significant delays in the delivery of cancer treatments in Canada. As cancer treatment and imaging volumes return to normal, radiologists will encounter more cases of chemotherapy-induced toxicities. These toxicities have varied appearances on imaging, and can affect multiple organ systems.

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Background: Computed tomography (CT) is routinely used to determine the suitability of potential living donor liver transplants, providing important information about liver size, vascular anatomy, and the presence of other diseases that would preclude it from safe donation. CT is not routinely used, however, when evaluating eligible deceased organ donors after brain death, a group which comprises most orthotopic liver transplants. After the installation of a CT scanner at a local procurement facility, CTs have been performed on potential deceased organ donors and used, in conjunction with other evaluative protocols, to help direct donation decisions and assist in procurement procedures.

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Unenhanced abdominopelvic CT is frequently performed in patients who are critically ill or have contraindications to intravenous contrast. These cases can be challenging to interpret for the radiologist. Attention to CT physics and care in optimizing image viewing through techniques such as windowing can maximize diagnostic yield.

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A pulmonary arteriovenous malformation (PAVM) is a fistulous connection between a pulmonary artery and a pulmonary vein that bypasses the normal pulmonary capillary bed resulting in a right-to-left shunt. Because of the potential for paradoxical emboli, PAVMs are treated when their feeding arteries exceed 3 mm or patients are symptomatic. PAVMs are often encountered in patients with suspected hereditary hemorrhagic telangiectasia (HHT).

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While many of the classic open surgical repairs are still used to repair the ascending aorta, management of the aortic arch has become more complex via implementation of newer open surgical and endovascular techniques. Furthermore, techniques are often combined in novel repairs or to allow extended anatomic coverage. As such, a framework that rests on understanding the expected postoperative appearance is necessary for the diagnostic radiologist to best interpret CT studies in these patients.

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We report two cases of myocarditis, in two young and previously healthy individuals, temporally related to the second dose of the mRNA-COVID-19 vaccine. Both patients developed acute chest pain, changes on electrocardiogram (ECG), and elevated serum troponin within two days of receiving their second dose. Cardiac magnetic resonance (CMR) findings were consistent with acute myocarditis.

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A 71-year-old man with coronary artery disease, sarcoid uveitis, and recurrent ventricular tachycardia treated with implantable cardioverter-defibrillator presented with increasing dyspnea for several months. Echocardiography showed a large echogenic mass causing severe narrowing of the proximal main pulmonary artery and a resultant gradient of 65 mm Hg. Ventilation-perfusion scintigraphy showed diffusely decreased perfusion of the left lung and an additional mismatched segmental perfusion defect in the left upper lobe.

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A pulmonary cyst usually refers to an air-filled space with a smooth, thin wall. Fluid-filled cystic lesions of the lungs include a range of etiologies such as true cysts, congenital malformations, infections, and benign and malignant neoplasms. With relatively little solid component, these lesions often have similar imaging appearances to one another.

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Central venous catheters (CVCs) are commonly used in patients in a variety of clinical settings, including the intensive care unit, general ward, and outpatient settings. After placement, the radiologist is frequently requested to evaluate the location of CVCs and deem them suitable for use. An understanding of the ideal location of catheter tips as well as the approach to identifying malpositioned catheter tips is essential to prevent improper use, recognize and/or prevent further injury, and direct potential lifesaving care.

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Aortic stenosis is the most prevalent valvular cardiovascular disease affecting the population over the age of 65 years. Transcatheter aortic valve replacement (TAVR) was developed as a minimally invasive surgical intervention to treat aortic stenosis in patients at high risk for surgical complications. Although the most commonly used approach for placement of a transcatheter aortic valve is in retrograde fashion via a transfemoral approach, narrowed luminal diameters, extensive atherosclerotic disease, or significant tortuosity may limit use of this route.

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Cardiac injury can occur in the setting of blunt and penetrating trauma resulting in significantly adverse clinical outcomes. Although the clinical presentation is variable and computed tomographic imaging is rarely performed to specifically evaluate for cardiac injury, the ability to recognize the findings of cardiac injury on computed tomographic examinations performed for thoracic trauma is essential to avoid misdiagnosis and direct potentially lifesaving interventions. This article reviews the direct and indirect computed tomographic findings of cardiac injury.

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Objective: The objective of this study was to identify CT findings and determine interobserver reliability of surgically proven gastric volvulus.

Materials And Methods: This single-center retrospective study included 30 patients (21 women, nine men; mean age, 73 years old) with surgically proven gastric volvulus who underwent preoperative CT and 31 age- and sex-matched control subjects (21 women, nine men; mean age, 74 years old) with large hiatal hernias who were imaged for reasons other than abdominal pain. Two blinded radiologists reviewed the CT images and recorded findings of organoaxial and mesenteroaxial gastric volvulus and ischemia.

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Simultaneous acquisition positron emission tomography-magnetic resonance imaging (PET-MRI) has the ability to combine anatomic information derived from cardiac MRI with quantitative capabilities of cardiac PET and MRI and the promise of molecular imaging by specific PET tracers. This combination of cardiac PET and MRI delivers a robust and comprehensive clinical examination. It has the potential to assess various cardiovascular conditions, including assessment of myocardial ischemia, infarction, and function, as well as specific characterization of inflammatory and infiltrative heart diseases such as cardiac sarcoid and amyloid.

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Patients with tetralogy of Fallot, pulmonary atresia, and multiple aortopulmonary collateral arteries (Tet PA MAPCAs) have a wide spectrum of anatomy and disease severity. Management of these patients can be challenging and often require multiple high-risk surgical and interventional catheterization procedures. These interventions are made challenging by complex anatomy that require the proceduralist to mentally reconstruct three-dimensional anatomic relationships from two-dimensional images.

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Coronary arterial abnormalities are uncommon findings in children that have profound clinical implications. Although anomalies of the coronary origins are well described, there are many other disease processes that affect the coronary arteries. Immune system-mediated diseases (eg, Kawasaki disease, polyarteritis nodosa, and other vasculiditides) can result in coronary arterial aneurysms, strictures, and abnormal tapering of the vessels.

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Injuries to the diaphragm muscle occur in penetrating and severe blunt trauma and can lead to delayed hernia formation. Computed tomography is the mainstay in the diagnosis of these injuries, which may be subtle at presentation. Imaging findings differ between blunt and penetrating trauma.

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Background: Blunt cardiac injury (BCI) may manifest as cardiac contusion or, more rarely, as pericardial or myocardial rupture. Computed tomography (CT) is performed in the vast majority of blunt trauma patients, but the imaging features of cardiac contusion are not well described.

Purpose: To evaluate CT findings and associated injuries in patients with clinically diagnosed BCI.

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The pregnant trauma patient presents an important and challenging encounter for the clinical team and radiologist. In this article, we present several key aspects of the imaging workup of pregnant trauma patients, beginning with a review of the modalities that are used in this setting. Ultrasonography plays an important role in initial evaluation of the fetus but a limited role in evaluation of maternal injuries.

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Left ventricular assist devices have become an increasingly common life-extending therapy for patients with end-stage heart failure. These devices may be used as a bridge to transplant, destination therapy, or to recovery, providing either pulsatile or nonpulsatile support. Because of the increasing frequency of left ventricular assist device utilization and the improved short-term and long-term survival after placement, there has been a parallel increase in the radiologic imaging of patients with these devices, mandating radiologists' awareness of the manifestations of common complications, including infection, thrombosis and embolism, cannula obstruction, hemorrhage, and complications of adjacent vessels and viscera, all of which will be discussed in this pictorial essay.

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