Diagnostic utility of additional whole-chest CT as part of an acute abdominal pain CT imaging pathway during the COVID-19 pandemic.

AIM: To evaluate the diagnostic utility of additional whole-chest computed tomography (CT) in identifying otherwise unheralded COVID-19 lung disease as part of an acute abdominal pain CT imaging pathway in response to the COVID-19 pandemic. MATERIALS AND METHODS: Consecutive patients (n=172) who underwent additional whole-chest CT via a COVID-19 acute abdominal pain CT imaging pathway between 27 March and 3 May 2020 were evaluated in this retrospective single-centre study. Chest CT examinations were graded as non-COVID-19, indeterminate for, or classic/probable for COVID-19. CT examinations in the latter two categories were further divided into one of three anatomical distributions (lung base, limited chest [below carina], whole chest [above carina]) based on location of findings. Reverse transcriptase-polymerase chain reaction (RT-PCR) results and clinical features of COVID-19 were assessed to determine if COVID-19 was clinically suspected at the time of CT referral. RESULTS: Twenty-seven of the 172 (15.7%) patients had CT features potentially indicative of COVID-19 pneumonia, 6/27 (3.5%) demonstrating a classic/probable pattern and 21/27 (12.2%) demonstrating an indeterminate pattern. After correlation with clinical features and RT-PCR 8/172 (4.7%) were defined as COVID-19 positive, of which only 1/172 (0.6%) was clinically unsuspected of COVID-19 at the time of CT referral. All COVID-19 positive cases could be identified on review of the lung base alone. CONCLUSION: Whole-chest CT as part of an acute abdominal pain CT imaging pathway has a very low diagnostic yield for our cohort of patients. All COVID-19-positive patients in our cohort were identified on review of the lung bases on the abdominal CT and this offers an alternative imaging approach in this patient group.

The safe practice of CT coronary angiography in adult patients in UK imaging departments.

Computed tomography coronary angiography is increasingly used in imaging departments in the investigation of patients with chest pain and suspected coronary artery disease. Due to the routine use of heart rate controlling medication and the potential for very high radiation doses during these scans, there is a need for guidance on best practice for departments performing this examination, so the patient can be assured of a good quality scan and outcome in a safe environment. This article is a summary of the document on 'Standards of practice of computed tomography coronary angiography (CTCA) in adult patients' published by the Royal College of Radiologists (RCR) in December 2014.

Cardiac MR assessment of microvascular obstruction.

Microvascular obstruction (MVO) is usually seen in a proportion of patients with acute myocardial infarction following reperfusion therapy of an occluded coronary artery. It is characterized by damage and dysfunction of the myocardial microvasculature with a no-reflow phenomenon within the infarct zone. While MVO may be demonstrated via a number of different imaging modalities, cardiac MR (CMR) enables accurate identification of MVO and also permits assessment of infarct extent and overall left ventricular function during the same imaging examination. We present a pictorial review of the characteristic appearances of MVO on CMR and highlight the importance of this imaging diagnosis for patient outcome following acute myocardial infarction.

Cardiac MR assessment of cardiac myxomas.

Cardiac myxomas are the most common benign primary cardiac tumour to present in adulthood. While most patients present with symptoms of cardiac obstruction, embolic phenomena or constitutional impairment, up to a fifth of patients remain asymptomatic and are incidentally diagnosed on imaging. Although echocardiography is usually the initial imaging modality used to evaluate these patients, cardiac MRI (CMR) has emerged over the past decade as the primary imaging modality in the assessment of patients with cardiac tumours. The superior tissue characterization capability of CMR means that it is able to determine the nature of some tumours pre-operatively and performs well in differentiating myxomas from thrombus. We present a pictorial review highlighting the key CMR features of myxomas and show how these lesions can be differentiated from thrombus and other cardiac masses.

The role of multidetector-row CT in the diagnosis, classification and management of acute aortic syndrome.

The term "acute aortic syndrome" (AAS) encompasses several non-traumatic life-threatening pathologies of the thoracic aorta presenting in patients with a similar clinical profile. These include aortic dissection, intramural haematoma and penetrating atherosclerotic ulcers. These different pathological entities can be indistinguishable on clinical grounds alone and may be confused with other causes of chest pain, including myocardial infarction. Multidetector-row CT (MDCT) is the current modality of choice for imaging AAS with a sensitivity and specificity approaching 100%. Early diagnosis and accurate radiological classification is associated with improved clinical outcomes in AAS. We review the characteristic radiological features of the different pathologies that encompass AAS and highlight the vital role of MDCT in determining the management of these life-threatening conditions.

Towards transparency in cardiac radiology: should CT coronary angiography radiation doses be published?

This is a commentary on the use of radiation dose as a quality marker in CT coronary angiography.

Left ventricular true and false aneurysms identified by cardiovascular magnetic resonance.

Left ventricular aneurysms are uncommon complications of myocardial infarction. However, it is important to identify them because they are associated with increased morbidity and mortality. True aneurysms tend to be managed conservatively whereas false aneurysms, because of the risk of rupture, are usually treated with urgent surgery. Distinguishing these two subtypes is therefore critical and cardiovascular magnetic resonance (MR) is being used more frequently to characterise the type of aneurysm as well as to provide clear three-dimensional images of aneurysm morphology. We present a very rare case of a true and a false aneurysm of the left ventricle in the same patient. MR enabled accurate delineation of both aneurysms and the late gadolinium-enhancement images provided evidence confirming both true and false aneurysms to be present.

Pericardial disease--anatomy and function.

Imaging of patients with suspected or known pericardial disease remains challenging. Echocardiography is the first-line investigation for pericardial disease but it has specific limitations in terms of its abilities to visualise the pericardium fully and to identify extracardiac pathology. Cardiac cross-sectional imaging by both MRI and CT has developed significantly and now has an important role in the investigation of pericardial disease. This article examines the appearances of both healthy and diseased pericardium using CT and MRI. The typical imaging findings across a wide range of conditions are illustrated and the roles of CT and MRI are reviewed. The relative merits and weaknesses of each modality are explored and the specific functional techniques that are available are introduced.

Cardiac drugs used in cross-sectional cardiac imaging: what the radiologist needs to know.

The demand for cross-sectional imaging of the heart is increasing dramatically and in many centres these imaging techniques are being performed by radiologists. Although radiologists are familiar with the computed tomography (CT) and magnetic resonance imaging (MRI) techniques to generate high-quality images and with using contrast agents, many are less familiar with administering the drugs necessary to perform CT coronary angiography and cardiac MR reliably. The aim of this article is to give an overview of the indications for and the contraindications to administering cardiac drugs in cross-sectional imaging departments. We also outline the complications that may be encountered and provide advice on how to treat these complications when they occur.

Cross-sectional imaging appearances of cardiac aneurysms.

Cardiac aneurysms are an uncommon presentation of cardiac disease, but are important to identify and accurately characterise. Traditionally, these aneurysms have been investigated with plain radiography, angiography and echocardiography. With the significant recent technical improvements in cross-sectional cardiac imaging, computed tomography (CT) and magnetic resonance imaging (MRI) are now becoming established as the definitive investigations. This article reviews the spectrum of locations of cardiac aneurysms and their appearance with particular reference to CT and MRI. We describe the relative merits of each technique and discuss how they may be used to direct clinical practice.

Cranial CT of the unconscious adult patient.

Unconscious patients are frequently referred to radiology departments for computed tomography (CT) of the brain. The objectives of these examinations are to define the underlying cause of impaired consciousness and in some cases to determine the severity of associated brain injury. There is often little history available to guide the clinician or radiologist, particularly in patients referred from the casualty department. In this review, we present the typical CT appearances of adult patients presenting with loss of consciousness for CT examination. We focus on the most common abnormalities that are identified in everyday radiological practice, emphasize important diagnostic signs that may enable a confident diagnosis to be made and discuss when further imaging may be warranted.

Painful sclerosis of the medial end of the clavicle.

Pain and swelling of the medial end of the clavicle may be associated with radiographic sclerosis. The commonest causes are osteoarthritis, infection and condensing osteitis of the clavicle. Distinguishing between these clinically and radiologically can be difficult but computed tomography (CT) and magnetic resonance imaging (MRI) are often useful for their differentiation. In this review, the typical imaging features of these conditions are presented with an emphasis on the CT and MRI appearances. These are correlated with clinical features, which together should enable a confident diagnosis to be made.