Interstitial lung abnormalities and pulmonary fibrosis in COVID-19 patients: a short-term follow-up case series

Fibrotic lung changes are well-known complications of SARS, MERS, and ARDS from other causes and are anticipated in recovered COVID patients. However, there is limited data so far showing a temporal relationship between lung changes on imaging in the acute phase and follow-up imaging after recovery from the infection. We present 12 patients who demonstrate the development of interstitial lung changes and pulmonary fibrosis in the same distribution and pattern as the acute phase findings, up to 6 months after the acute infection, demonstrating a direct relationship between these changes and COVID-19 pneumonia.     

SARS-CoV-2 reinfection: “New baseline” imaging concept in the era of COVID-19

Recent reports have suggested COVID-19 relapse or reinfection may lead to readmission, which may cause a diagnostic challenge between recently infected patients and reinfections. Compounding this problem is the post-viral lung sequela that may be expected after COVID-19 pneumonia, similar to both SARS and MERS. Although chest imaging may play a role in the diagnosis of primary SARS-CoV-2 infection, reinfection or relapse of COVID-19 will have similar imaging findings. A “new-baseline” imaging can be obtained from COVID-19 patients at the time of hospital discharge or clinical recovery. This new reference can not only determine if readmissions are from relapse or reinfection of COVID-19, resolving COVID-19 or potentially a different viral infection (influenza), but also for long term sequela of COVID-19 lung infection. Strategic use of imaging before discharge may be helpful in the subset of the population at the highest risk of a secondary viral infection such as influenza. Determining the residual abnormalities in post-discharge imaging can guide us in the long-term management of patients for many years to come.     

Follow-up computed tomography scan in post-COVID-19 pneumonia

The coronavirus disease 2019 (COVID-19) global pandemic can be a severe illness that leads to morbidity and mortality. With the increasing number of COVID-19 pneumonia survivors, several long-term changes may persist, including abnormal imaging of lung parenchyma. In addition to the clinical course, it is vital to follow up on pulmonary imaging during the post-infectious period, which is not routinely required in other common pulmonary diagnoses. Computed tomography (CT) scan of the chest is an effective and diagnostic tool for pneumonia which gives an insight into structural abnormalities within the lungs, complications, and possible progression of the disease. Several studies have monitored COVID-19 pneumonia and its complications using serial CT chest imaging from the initial phase of infection, hospitalization, and post-discharge. Nonetheless, long-term follow-up imaging data in post-COVID-19 is still limited. We have summarized the findings utilizing a systematic review of the literature regarding COVID-19 pneumonia imaging, including long-term follow-up.     

Imaging of Coronavirus Disease 2019 Infection From Head to Toe: A Primer for the Radiologist

Coronavirus Disease 2019 (COVID-19) disease has rapidly spread around the world after initial identification in Wuhan, China, in December 2019. Most common presentation is mild or asymptomatic disease, followed by pneumonia, and rarely- multiorgan failure and Acute Respiratory Distress Syndrome (ARDS). Knowledge about the pathophysiology, imaging and treatment of this novel virus is rapidly evolving due to ongoing worldwide research. Most common imaging modalities utilized during this pandemic are chest radiography and HRCT with findings of bilateral peripheral, mid and lower zone GGO and/or consolidation, vascular enlargement and crazy paving. HRCT is also useful for prognostication and follow-up of severely ill COVID-19 patients. Portable radiography allows follow-up of ICU patients & obviates the need of shifting critically ill patients and disinfection of CT room. As the pandemic has progressed, numerous neurologic manifestations have been described in COVID-19 including stroke, white matter hyperintensities and demyelination on MRI. Varying abdominal presentations have been described, which on imaging either show evidence of COVID-19 pneumonia in lung bases or show abdominal findings including bowel thickening and vascular thrombosis. Numerous thrombo-embolic and cardiovascular complications have also been described in COVID-19 including arterial and venous thrombosis, pulmonary embolism and myocarditis. It is imperative for radiologists to be aware of all the varied faces of this disease on imaging, as they may well be the first physician to suspect the disease. This article aims to review the multimodality imaging manifestations of COVID-19 disease in various organ systems from head to toe.     

QIBA guidance: Computed tomography imaging for COVID-19 quantitative imaging applications

As the COVID-19 pandemic impacts global populations, computed tomography (CT) lung imaging is being used in many countries to help manage patient care as well as to rapidly identify potentially useful quantitative COVID-19 CT imaging biomarkers. Quantitative COVID-19 CT imaging applications, typically based on computer vision modeling and artificial intelligence algorithms, include the potential for better methods to assess COVID-19 extent and severity, assist with differential diagnosis of COVID-19 versus other respiratory conditions, and predict disease trajectory. To help accelerate the development of robust quantitative imaging algorithms and tools, it is critical that CT imaging is obtained following best practices of the quantitative lung CT imaging community. Toward this end, the Radiological Society of North America's (RSNA) Quantitative Imaging Biomarkers Alliance (QIBA) CT Lung Density Profile Committee and CT Small Lung Nodule Profile Committee developed a set of best practices to guide clinical sites using quantitative imaging solutions and to accelerate the international development of quantitative CT algorithms for COVID-19. This guidance document provides quantitative CT lung imaging recommendations for COVID-19 CT imaging, including recommended CT image acquisition settings for contemporary CT scanners. Additional best practice guidance is provided on scientific publication reporting of quantitative CT imaging methods and the importance of contributing COVID-19 CT imaging datasets to open science research databases.     

The potential application of dual-energy subtraction radiography for COVID-19 pneumonia imaging

X-ray imaging plays a crucial role in the confirmation of COVID-19 pneumonia. Chest X-ray radiography and CT are two major imaging techniques that are currently adopted in the diagnosis of COVID-19 pneumonia. However, dual-energy subtraction radiography is hardly discussed as potential COVID-19 imaging application. More advanced X-ray radiography equipment often supports dual-energy subtraction X-ray radiography. Dual-energy subtraction radiography enables the calculation of pseudo-radiographs, in which bones are removed and only soft-tissues are highlighted. In this commentary, the author would like to draw the attention to the potential use of dual-energy subtraction X-ray radiography (i.e. soft-tissue pseudo-radiography) for the assessment and the longitudinal follow-up of COVID-19 pneumonia.     

Chest radiological finding of COVID-19 in patients with and without diabetes mellitus: Differences in imaging finding

The pandemic of novel coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Diabetes mellitus is a risk factor for developing severe illness and a leading cause of death in patients with COVID-19. Diabetes can precipitate hyperglycaemic emergencies and cause prolonged hospital admissions. Insulin resistance is thought to cause endothelial dysfunction, alveolar capillary micro-angiopathy and interstitial lung fibrosis through pro-inflammatory pathways. Autopsy studies have also demonstrated the presence of microvascular thrombi in affected sections of lung, which may be associated with diabetes. Chest imaging using x-ray (CXR) and computed tomography (CT) of chest is used to diagnose, assess disease progression and severity in COVID-19. This article reviews current literature regarding chest imaging findings in patients with diabetes affected by COVID-19. A literature search was performed on PubMed. Patients with diabetes infected with SARS-CoV-2 are likely to have more severe infective changes on CXR and CT chest imaging. Severity of airspace consolidation on CXR is associated with higher mortality, particularly in the presence of co-morbidities such as ischaemic heart disease. Poorly controlled diabetes is associated with more severe acute lung injury on CT. However, no association has been identified between poorly-controlled diabetes and the incidence of pulmonary thromboembolism in patients with COVID-19.     

Abdominal imaging in COVID-19

Initially thought of as a respiratory infection, coronavirus disease-2019 (COVID-19) is now recognized as a complex disease with a wide clinical spectrum, including digestive involvement. While several studies have evaluated chest imaging findings in COVID-19, few papers have looked at the abdominal imaging features of these patients. Liver, biliary, pancreas and bowel involvement have been reported in COVID-19 infected patients. In this review, we aim to summarize currently available data related to abdominal imaging techniques in COVID-19, in accordance with relevant clinical and laboratory workup of these patients. Underlying mechanisms, indications and imaging findings related to COVID-19 are discussed based on published data. Also, practice points for clinicians are highlighted in order to adequately recognize digestive-related injuries of severe acute respiratory syndrome coronavirus 2 infection. While there’s been a steady accumulation of data with respect to abdominal imaging findings in COVID-19, currently available recommendations are based on limited research. There is a wide spectrum of abdominal imaging findings in COVID-19, which includes hepato-biliary, pancreatic and luminal pathology.     

Incidental radiological findings suggestive of COVID-19 in asymptomatic patients

Despite routine screening of patients for coronavirus disease 2019 (COVID-19) symptoms and signs at hospital entrances, patients may slip between the cracks and be incidentally discovered to have lung findings that could indicate COVID-19 infection on imaging obtained for other reasons. Multiple case reports and case series have been published to identify the pattern of this highly infectious disease. This article addresses the radiographic findings in different imaging modalities that may be incidentally seen in asymptomatic patients who carry COVID-19. In general, findings of COVID-19 infection may appear in computed tomography (CT), magnetic resonance imaging, positron emission tomography-CT, ultrasound, or plain X-rays that show lung or only apical or basal cuts. The identification of these characteristics by radiologists and clinicians is crucial because this would help in the early recognition of cases so that a rapid treatment protocol can be established, the immediate isolation to reduce community transmission, and the organization of close monitoring. Thus, it is important to both the patient and the physician that these findings are highlighted and reported.     

Renal ultrasound findings secondary to COVID-19 related collapsing focal segmental glomerulosclerosis – A case report

SARS-CoV-2 (COVID-19) is well known to have extrapulmonary manifestations, including acute renal failure. While radiologic findings of COVID-19 pulmonary-involvement have been described, renal findings associated with COVID-19 have not. We present a case of a 38-year-old Afro-Caribbean female diagnosed with COVID-19 whose renal ultrasound showed increased parenchymal echogenicity, decreased global color Doppler signal with elevated resistive indices, but no large vessel thrombi. Non-targeted renal biopsy demonstrated collapsing focal segmental glomerulosclerosis (FSGS), likely secondary to COVID-19 infection, which may be a specific manifestation of this disease that has been predominantly reported in Black patients. We report several findings on renal ultrasound with duplex Doppler not previously associated with COVID, specifically with FSGS, which in conjunction can be useful to both the radiologist and the clinician, potentially pointing them in the direction of this diagnosis and early treatment.     

18F-FDG PET/CT在新型冠状病毒肺炎诊断中的应用

新型冠状病毒肺炎（COVID-19）被发现以来,迅速蔓延,其早期诊断有利于患者的及时救治和疾病进一步传播的有效控制。目前,诊断的依据是流行病史、临床表现、影像学特征和逆转录聚合酶链式反应（RT-PCR）检测结果,其中RT-PCR检测到新型冠状病毒核酸阳性是COVID-19确诊的主要依据,影像学特征尤其是肺部高分辨率CT表现则是诊断该病的重要临床依据。作为一种被广泛应用的影像学方法,18F-FDG PET/CT在COVID-19中的价值仍未可知。笔者分析了18F-FDG PET/CT在COVID-19中的诊断和鉴别诊断的价值,以及评估COVID-19患者纵隔淋巴结受累情况方面的潜在应用,讨论了COVID-19患者肺外器官和组织受累可能出现的18F-FDG PET/CT影像学表现。     

COVID-19 and pulmonary tuberculosis – A diagnostic dilemma

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Meanwhile, pulmonary tuberculosis(TB) is one of the most common infective lung diseases in developing nations. The concurrence of pulmonary TB and COVID-19 can lead to poor prognosis, owing to the pre-existing lung damage caused by TB. Case presentation: We describe the imaging findings in 3 cases of COVID-19 pneumonia with co-existing pulmonary TB on HRCT thorax. The concurrence of COVID-19 and pulmonary TB can be a diagnostic dilemma. Correct diagnosis and prompt management is imperative to reduce mortality and morbidity. Hence it is pertinent for imaging departments to identify and report these distinct entities when presenting in conjunction.     

Lung ultrasound education: simulation and hands-on

COVID-19 can cause damage to the lung, which can result in progressive respiratory failure and potential death. Chest radiography and CT are the imaging tools used to diagnose and monitor patients with COVID-19. Lung ultrasound (LUS) during COVID-19 is being used in some areas to aid decision-making and improve patient care. However, its increased use could help improve existing practice for patients with suspected COVID-19, or other lung disease. A limitation of LUS is that it requires practitioners with sufficient competence to ensure timely, safe, and diagnostic clinical/imaging assessments. This commentary discusses the role and governance of LUS during and beyond the COVID-19 pandemic, and how increased education and training in this discipline can be undertaken given the restrictions in imaging highly infectious patients. The use of simulation, although numerical methods or dedicated scan trainers, and machine learning algorithms could further improve the accuracy of LUS, whilst helping to reduce its learning curve for greater uptake in clinical practice.     

A practical approach to imaging characteristics and standardized reporting of COVID-19:A radiologic review

Novel coronavirus (2019-nCoV),also known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),is a pathogen that has caused a rapidly spreading pandemic all over the world.The primary mean of transmission is inhalation with a predilection for respiratory system involvement,especially in the distal airways.The disease that arises from this novel coronavirus is named coronavirus disease 2019 (COVID-19).COVID-19 may have a rapid and devastating course in some cases leading to severe complications and death.Radiological imaging methods have an invaluable role in diagnosis,follow-up,and treatment.In this review,radiological imaging findings of COVID-19 have been systematically reviewed based on the published literature so far.Radiologic reporting templates are also emphasized from a different point of view,considering specific distinctive patterns of involvement.     

Role of cardiac magnetic resonance imaging in the diagnosis and management of COVID-19 related myocarditis: Clinical and imaging considerations

There is a growing evidence of cardiovascular complications in coronavirus disease 2019 (COVID-19) patients. As evidence accumulated of COVID-19 mediated inflammatory effects on the myocardium, substantial attention has been directed towards cardiovascular imaging modalities that facilitate this diagnosis. Cardiac magnetic resonance imaging (CMRI) is the gold standard for the detection of structural and functional myocardial alterations and its role in identifying patients with COVID-19 mediated cardiac injury is growing. Despite its utility in the diagnosis of myocardial injury in this population, CMRI’s impact on patient management is still evolving. This review provides a framework for the use of CMRI in diagnosis and management of COVID-19 patients from the perspective of a cardiologist. We review the role of CMRI in the management of both the acutely and remotely COVID-19 infected patient. We discuss patient selection for this imaging modality; T1, T2, and late gadolinium enhancement imaging techniques; and previously described CMRI findings in other cardiomyopathies with potential implications in COVID-19 recovered patients.     

Axillary adenopathy following COVID-19 vaccination: A single institution case series

Axillary adenopathy is a potential side effect following COVID-19 vaccination. We report four cases of axillary adenopathy in the setting of recent COVID-19 vaccination (Moderna and Pfizer-BioNTech) at our institution. Our cases show unilateral axillary adenopathy, as well as adenopathy persisting for two to three weeks following vaccination. The Society of Breast Imaging (SBI) and Harvard University have each released guidelines for management of axillary adenopathy following COVID-19 vaccination. While SBI recommends short term imaging 4–12 weeks following the second dose, a group of physicians from Harvard suggest clinical follow-up with sonographic imaging if clinical concern persists beyond six weeks. As a larger percentage of the general population becomes vaccinated, it is important for radiologists to be aware of potential vaccine-induced ipsilateral axillary adenopathy on screening and diagnostic breast imaging to reduce the number of unnecessary biopsies performed in this patient population.     

Can autofluorescence and fluorescence imaging be useful in fight with COVID-19 pandemia?

The entire medical world gathers information related to the COVID-19 pandemic, including its spread analysis, disease characteristics, morbidity and mortality statistics, as well as factors limiting and promoting infection and severe course, and above all potential treatment options. Scientific research is being carried out on a large scale on methods of early detection of COVID-19 infection, including imaging methods such as computed tomography or ultrasound imaging. The importance of imaging methods is increasingly emphasized in the literature as sensitive and specific, often with greater clinical utility than mass-applied serological tests. Especially in large urban agglomerations such as Silesia, the wide availability of these imaging methods as screening methods in the clinical assessment of potentially infectious patients seems to be important. The literature on the COVID-19 epidemic emphasizes the significant role of integrated diagnostic methods including basic science as well as radiological and endoscopic imaging methods in the diagnosis of COVID-19 infection and its possible complications. The study presents potential possibilities of using the phenomena of autofuorescence and fluorescence in supporting the diagnosis of patients with suspected COVID-19 infection. The study presents preliminary results of case studies of patients suspected of being infected with COVID-19, and shows the multidimensional application of fluorescent phenomena in supporting diagnostics. One of the main tools used in the study is autofluorescent bronchoscopy as a method that, in synchronization with high resolution tomography analysis, significantly facilitates obtaining representative material for RT-PCR. The study also showed the potential for assessing fluorescent material under fluorescence microscopy, which can significantly facilitate diagnostics in the future and speed up existing screening tests to complement genetic diagnostics.     

Current status quo on COVID-19 including chest imaging

With each day the number coronavirus disease 2019 (COVID-19) cases continue to rise rapidly and our imaging knowledge of this disease is expeditiously evolving. The role of chest computed tomography (CT) in the screening or diagnosis of COVID-19 remains the subject of much debate. Despite several months having passed since identifying the disease, and numerous studies related to it, controversy and concern still exists regarding the widespread use of chest CT in the evaluation and management of COVID-19 suspect patients. Several institutes and organizations around the world have released guidelines, recommendations and statements against the use of CT for diagnosing or screening COVID-19 infection and advocating its use only for those cases with a strong clinical suspicion of complication or an alternate diagnosis. However, these guidelines and recommendations are in disagreement with majority of the widely available literature, which strongly favour CT as a pivotal tool in the early diagnosis, management and even follow-up of COVID-19 infection. This article besides comprehensively reviewing the current status quo on COVID-19 disease in general, also writes upon the current consensus statements/recommendations on the use of diagnostic imaging in COVID-19 as well as highlighting the precautions and various disinfection procedures being employed world-wide at the workplace to prevent the spread of infection.