Improved pulmonary function and exercise tolerance despite persistent pulmonary fibrosis over 1 year after severe COVID-19 infection.

We conducted a prospective single-centre cohort study of 104 multi-ethnic severe COVID-19 survivors from the first wave of the pandemic 15 months after hospitalisation. Of those who were assessed at 4 and 15 months, improvement of ground glass opacities correlated with worsened fibrotic reticulations. Despite a high prevalence of fibrotic patterns (64%), pulmonary function, grip strength, 6 min walk distance and frailty normalised. Overall, dyspnoea, cough and exhaustion did not improve and were not correlated with pulmonary function or radiographic fibrosis at 15 months, suggesting non-respiratory aetiologies. Monitoring persistent, and often subclinical, fibrotic interstitial abnormalities will be needed to determine their potential for future progression.

Radiology of fibrosis part III: genitourinary system.

Fibrosis is a pathological process involving the abnormal deposition of connective tissue, resulting from improper tissue repair in response to sustained injury caused by hypoxia, infection, or physical damage. It can impact any organ, leading to their dysfunction and eventual failure. Additionally, tissue fibrosis plays an important role in carcinogenesis and the progression of cancer.Early and accurate diagnosis of organ fibrosis, coupled with regular surveillance, is essential for timely disease-modifying interventions, ultimately reducing mortality and enhancing quality of life. While extensive research has already been carried out on the topics of aberrant wound healing and fibrogenesis, we lack a thorough understanding of how their relationship reveals itself through modern imaging techniques.This paper focuses on fibrosis of the genito-urinary system, detailing relevant imaging technologies used for its detection and exploring future directions.

Radiology of fibrosis. Part I: Thoracic organs.

Sustained injury from factors such as hypoxia, infection, or physical damage may provoke improper tissue repair and the anomalous deposition of connective tissue that causes fibrosis. This phenomenon may take place in any organ, ultimately leading to their dysfunction and eventual failure. Tissue fibrosis has also been found to be central in both the process of carcinogenesis and cancer progression. Thus, its prompt diagnosis and regular monitoring is necessary for implementing effective disease-modifying interventions aiming to reduce mortality and improve overall quality of life. While significant research has been conducted on these subjects, a comprehensive understanding of how their relationship manifests through modern imaging techniques remains to be established. This work intends to provide a comprehensive overview of imaging technologies relevant to the detection of fibrosis affecting thoracic organs as well as to explore potential future advancements in this field.

Radiology of fibrosis part II: abdominal organs.

Fibrosis is the aberrant process of connective tissue deposition from abnormal tissue repair in response to sustained tissue injury caused by hypoxia, infection, or physical damage. It can affect almost all organs in the body causing dysfunction and ultimate organ failure. Tissue fibrosis also plays a vital role in carcinogenesis and cancer progression. The early and accurate diagnosis of organ fibrosis along with adequate surveillance are helpful to implement early disease-modifying interventions, important to reduce mortality and improve quality of life. While extensive research has already been carried out on the topic, a thorough understanding of how this relationship reveals itself using modern imaging techniques has yet to be established. This work outlines the ways in which fibrosis shows up in abdominal organs and has listed the most relevant imaging technologies employed for its detection. New imaging technologies and developments are discussed along with their promising applications in the early detection of organ fibrosis.

Incidence of Interstitial Lung Abnormalities: The MESA Lung Study.

The incidence of newly developed interstitial lung abnormalities (ILA) and fibrotic ILA have not been previously reported.Trained thoracic radiologists evaluated 13 944 cardiac CT scans for the presence of ILA in 6197 Multi-Ethnic Study of Atherosclerosis longitudinal cohort study participants >45 years of age from 2000 to 2012. 5% of the scans were re-read by the same or a different observer in a blinded fashion. After exclusion of participants with ILA at baseline, incidence rates and incidence rate ratios for ILA and fibrotic ILA were calculated.The intra-reader agreement of ILA was 92.0% (Gwet AC1=0.912, ICC=0.982) and the inter-reader agreement of ILA was 83.5% (Gwet AC1=0.814; ICC=0.969). Incidence of ILA and fibrotic ILA was estimated to be 13.1 cases/1000 person-years and 3.5/1000 person-years, respectively. In multivariable analyses, age (HR 1.06 (1.05, 1.08), p <0.001; HR 1.08 (1.06, 1.11), p <0.001), high attenuation area (HAA) at baseline (HR 1.05 (1.03, 1.07), p <0.001; HR 1.06 (1.02, 1.10), p=0.002), and the MUC5B promoter SNP (HR 1.73 (1.17, 2.56) p=0.01; HR 4.96 (2.68, 9.15), p <0.001) were associated with incident ILA and fibrotic ILA, respectively. Ever smoking (HR 2.31 (1.34, 3.96), p= 0.002) and an IPF polygenic risk score (HR 2.09 (1.61-2.71), p<0.001) were associated only with incident fibrotic ILA.Incident ILA and fibrotic ILA were estimated by review of cardiac imaging studies. These findings may lead to wider application of a screening tool for atherosclerosis to identify preclinical lung disease.

Pulmonary fibrosis 4 months after COVID-19 is associated with severity of illness and blood leucocyte telomere length.

The risk factors for development of fibrotic-like radiographic abnormalities after severe COVID-19 are incompletely described and the extent to which CT findings correlate with symptoms and physical function after hospitalisation remains unclear. At 4 months after hospitalisation, fibrotic-like patterns were more common in those who underwent mechanical ventilation (72%) than in those who did not (20%). We demonstrate that severity of initial illness, duration of mechanical ventilation, lactate dehydrogenase on admission and leucocyte telomere length are independent risk factors for fibrotic-like radiographic abnormalities. These fibrotic-like changes correlate with lung function, cough and measures of frailty, but not with dyspnoea.

The role of initial chest X-ray in triaging patients with suspected COVID-19 during the pandemic.

PURPOSE: The purpose of our research is to evaluate the usefulness of chest X-ray for triaging patients with suspected COVID-19 infection. METHODS: IRB approval was obtained to allow a retrospective review of adult patients who presented to the Emergency Department with a complaint of fever, cough, dyspnea or hypoxia and had a chest X-ray between 12 March 2020 and 26 March 2020. The initial chest X-ray was graded on a scale of 0-3 with grade 0 representing no alveolar opacities, grade 1: < 1/3 alveolar opacities of the lung, Grade 2: 1/3 to 2/3 lung with alveolar opacities and grade 3: > 2/3 alveolar opacities of the lung. Past medical history of diabetes and hypertension, initial oxygen saturation, COVID-19 testing results, intubation, and outcome were also collected. RESULTS: Four hundred ten patient chest X-rays were reviewed. Oxygen saturation and X-ray grade were both significantly associated with the length of stay in hospital, the hazard ratio (HR) of discharge was 1.05 (95% CI [1.01, 1.09], p = 0.017) and 0.61 (95% CI [0.51, 0.73], p < 0.001), respectively. In addition, oxygen saturation and X-ray grade were significant predictors of intubation (odds ratio (OR) of intubation is 0.88 (95% CI [0.81, 0.96], p = 0.004) and 3.69 (95% CI [2.25, 6.07], p < 0.001). CONCLUSIONS: Initial chest X-ray is a useful tool for triaging those subjects who might have poor outcomes with suspected COVID-19 infection and benefit most from hospitalization.

Radiographic features of pneumonitis in patients treated with immunotherapy compared to traditional chemotherapy for non-small cell lung cancer.

BACKGROUND: Pneumonitis has been described as a side effect of immunotherapy as well as traditional chemotherapy. Although immune-related adverse event (IRAE) pneumonitis has been extensively characterized, the relationship between IRAE pneumonitis and pneumonitis secondary to chemotherapy is less clear. Here, we present the first analysis of radiographic features of pneumonitis secondary to immunotherapy compared to chemotherapy. METHODS: Using our radiology records system, we searched chest computed tomography (CT) reports for the term "pneumonitis". We evaluated medical records to establish chronicity of pneumonitis occurring after medication administration and excluded cases where radiation therapy appeared to be the cause of pneumonitis. We also obtained information regarding demographic, clinical, and treatment characteristics for comparison. RESULTS: Patients treated with immunotherapy demonstrated more specific features of pneumonitis including consolidation, ground glass opacities, septal thickening, traction bronchiectasis, and pulmonary nodules compared to those treated with chemotherapy. Immunotherapy treatment correlated with the development of pulmonary nodules (p = 0.048), and administration of more than one immunotherapy agent correlated with a greater incidence of development of nodules (p = 0.050). Radiographic features in patients treated with immunotherapy all decreased over time. Conversely, in patients treated with chemotherapy the incidence of ground glass opacities, traction bronchiectasis, pulmonary nodules, and mediastinal/hilar adenopathy increased over time. CONCLUSIONS: IRAE-pneumonitis has distinct features and a distinct clinical course compared to pneumonitis secondary to chemotherapy. Importantly, IRAE-pneumonitis features decreased over time, suggesting that careful consideration of the benefit-risk ratio may allow for continuation of immunotherapy in some patients who develop pneumonitis.

The Macklin effect closely correlates with pneumomediastinum in acutely ill intubated patients with COVID-19 infection.

PURPOSE: Patients with COVID-19 infection are frequently found to have pulmonary barotrauma. Recent work has identified the Macklin effect as a radiographic sign that often occurs in patients with COVID-19 and may correlate with barotrauma. METHODS: We evaluated chest CT scans in COVID-19 positive mechanically ventilated patients for the Macklin effect and any type of pulmonary barotrauma. Patient charts were reviewed to identify demographic and clinical characteristics. RESULTS: The Macklin effect on chest CT scan was identified in a total of 10/75 (13.3%) COVID-19 positive mechanically ventilated patients; 9 developed barotrauma. Patients with the Macklin effect on chest CT scan had a 90% rate of pneumomediastinum (p < 0.001) and a trend toward a higher rate of pneumothorax (60%, p = 0.09). Pneumothorax was most frequently omolateral to the site of the Macklin effect (83.3%). CONCLUSION: The Macklin effect may be a strong radiographic biomarker for pulmonary barotrauma, most strongly correlating with pneumomediastinum. Studies in ARDS patients without COVID-19 are needed to validate this sign in a broader population. If validated in a broad population, future critical care treatment algorithms may include the Macklin sign for clinical decision making and prognostication.

Imaging the Side Effects of CAR T Cell Therapy: A Primer for the Practicing Radiologist.

Chimeric antigen receptor (CAR) T cell therapy is a revolutionary form of immunotherapy that has proven to be efficacious in the treatment of many hematologic cancers. CARs are modified T lymphocytes that express an artificial receptor specific to a tumor-associated antigen. These engineered cells are then reintroduced to upregulate the host immune responses and eradicate malignant cells. While the use of CAR T cell therapy is rapidly expanding, little is known about how common side effects such as cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity (ICANS) present radiographically. Here we provide a comprehensive review of how side effects present in different organ systems and how they can be optimally imaged. Early and accurate recognition of the radiographic presentation of these side effects is critical to the practicing radiologist and their patients so that these side effects can be promptly identified and treated.

Impact of the COVID-19 Pandemic on Trends in Cardiothoracic Imaging.

Introduction: Here, we evaluate the effect of the COVID-19 pandemic on utilization of cardiothoracic imaging studies. Methods: We queried our radiology record system to retrospectively identify numbers of specific key cardiothoracic imaging studies for five years prior and during the COVID-19 pandemic. Statistical analysis was performed to evaluate changes in the number of exams in 2020 and 2021 compared to 2019. Results: Five-year retrospective analysis demonstrated progressive increases in nearly all cross-sectional studies. In 2020, daily chest radiograph utilization decreased with an overall number of daily radiographs of 406 (SD = 73.1) compared to 480 per day in 2019 (SD = 82.6) (p < 0.0001). Portable radiograph utilization was increased in 2020 averaging 320 (SD = 68.2) films daily in 2020 compared to 266 (SD = 29.1) in 2019 (p < 0.0001). Utilization of thoracic CT was decreased during the pandemic, with 21.8 (SD = 12.9) studies daily compared to 52.0 (SD = 21.4) (p < 0.0001) studies daily in 2019. Cardiac imaging utilization was also substantially decreased in 2020 compared to 2019, averaging a total of 3.8 (SD = 3.2) versus 10.8 (SD = 6.6) studies daily and 0.88 (SD = 1.7) versus 2.5 (SD = 2.3) studies daily for CT and MRI, respectively. Evaluation of cardiothoracic imaging for the subsequent 18 months after New York's entry to phase I recovery in June 2020 demonstrated that by one year after the emergence of COVID-19 imaging utilization had recovered to prepandemic levels. Cardiac imaging continued to increase throughout the chronic phase of the COVID-19 pandemic, reaching almost twice the prepandemic levels by the end of 2021. Conclusion: COVID-19 has had far-reaching effects on medicine and public health. Here, we demonstrate decreases in all cross-sectional cardiothoracic imaging studies, closely mirroring findings in other fields during the height of the pandemic, which have since rebounded.

Checkpoint Inhibitor Immune-Related Adverse Events: A Multimodality Pictorial Review.

Cancer immunotherapies are drugs that modulate the body's own immune system as an anticancer strategy. Checkpoint inhibitor immunotherapies interfere with cell surface binding proteins that function to promote self-recognition and tolerance, ultimately leading to upregulation of the immune response. Given the striking success of these agents in early trials in melanoma and lung cancer, they have now been studied in many types of cancer and have become a pillar of anticancer therapy for many tumor types. However, abundant upregulation results in a new class of side effects, known as immune-related adverse events (IRAEs). It is critical for the practicing radiologist to be able to recognize these events to best contribute to care for patients on checkpoint inhibitor immunotherapy. Here, we provide a comprehensive system-based review of immune-related adverse events and associated imaging findings. Further, we detail the best imaging modalities for each as well as describe problem solving modalities. Given that IRAEs can be subclinical before becoming clinically apparent, radiologists may be the first provider to recognize them, providing an opportunity for early treatment. Awareness of IRAEs and how to best image them will prepare radiologists to make a meaningful contribution to patient care as part of the clinical team.

Acute pulmonary function decline and radiographic abnormalities: chronic cause?

Nitrofurantoin is a cause of drug-induced pneumonitis and can result in clinically significant respiratory symptoms manifesting as interstitial lung disease on chest CT, even if the patient has been taking the drug chronically without side-effects https://bit.ly/3v2m29h.

Acute myocardial infarction secondary to COVID-19 infection: A case report and review of the literature.

BACKGROUND: Thrombotic complications of COVID-19 infection have become increasingly apparent as the disease has infected a growing number of individuals. Although less common than upper respiratory symptoms, thrombotic complications are not infrequent and may result in severe and long-term sequelae. Common thrombotic complications include pulmonary embolism, cerebral infarction, or venous thromboembolism; less commonly seen are acute myocardial injury, renal artery thrombosis, and mesenteric ischemia. Several case reports and case series have described acute myocardial injury in patients with COVID-19 characterized by elevations in serum biomarkers. CASE REPORT: Here, we report the first case to our knowledge of a patient with acute coronary syndrome confirmed on catheter angiography and cardiac MRI. This patient was found to additionally have a left ventricular thrombus and ultimately suffered an acute cerebral infarction. Recognition of thrombotic complications in the setting of COVID-19 infection is essential for initiating appropriate therapy. CONCLUSIONS: In acute myocardial injury, given the different treatment strategies for myocarditis versus acute myocardial infarction secondary to coronary artery thrombus, imaging can play a key role in clinical decision making for patients.

Deep Learning of Computed Tomography Virtual Wedge Resection for Prediction of Histologic Usual Interstitial Pneumonitis.

Rationale: The computed tomography (CT) pattern of definite or probable usual interstitial pneumonia (UIP) can be diagnostic of idiopathic pulmonary fibrosis and may obviate the need for invasive surgical biopsy. Few machine-learning studies have investigated the classification of interstitial lung disease (ILD) on CT imaging, but none have used histopathology as a reference standard.Objectives: To predict histopathologic UIP using deep learning of high-resolution computed tomography (HRCT).Methods: Institutional databases were retrospectively searched for consecutive patients with ILD, HRCT, and diagnostic histopathology from 2011 to 2014 (training cohort) and from 2016 to 2017 (testing cohort). A blinded expert radiologist and pulmonologist reviewed all training HRCT scans in consensus and classified HRCT scans based on the 2018 American Thoracic Society/European Respriatory Society/Japanese Respiratory Society/Latin American Thoracic Association diagnostic criteria for idiopathic pulmonary fibrosis. A convolutional neural network (CNN) was built accepting 4 × 4 × 2 cm virtual wedges of peripheral lung on HRCT as input and outputting the UIP histopathologic pattern. The CNN was trained and evaluated on the training cohort using fivefold cross validation and was then tested on the hold-out testing cohort. CNN and human performance were compared in the training cohort. Logistic regression and survival analyses were performed.Results: The CNN was trained on 221 patients (median age 60 yr; interquartile range [IQR], 53-66), including 71 patients (32%) with UIP or probable UIP histopathologic patterns. The CNN was tested on a separate hold-out cohort of 80 patients (median age 66 yr; IQR, 58-69), including 22 patients (27%) with UIP or probable UIP histopathologic patterns. An average of 516 wedges were generated per patient. The percentage of wedges with CNN-predicted UIP yielded a cross validation area under the curve of 74% for histopathological UIP pattern per patient. The optimal cutoff point for classifying patients on the training cohort was 16.5% of virtual lung wedges with CNN-predicted UIP and resulted in sensitivity and specificity of 74% and 58%, respectively, in the testing cohort. CNN-predicted UIP was associated with an increased risk of death or lung transplantation during cross validation (hazard ratio, 1.5; 95% confidence interval, 1.1-2.2; P = 0.03).Conclusions: Virtual lung wedge resection in patients with ILD can be used as an input to a CNN for predicting the histopathologic UIP pattern and transplant-free survival.

Optimizing Cardiac CT Protocols for Comprehensive Acquisition Prior to Percutaneous MV and TV Repair/Replacement.

Clinical trials of transcatheter mitral valve and tricuspid valve repair and replacement devices have begun in earnest, with the ultimate goal of providing definitive, nonsurgical treatment for the millions of patients with severe, symptomatic regurgitation, many of whom are too high risk or inoperable for a surgical approach. Computed tomography (CT) angiography offers the potential for detailed anatomic assessment in this patient population, but its optimal implementation for patients with mitral and tricuspid disease requires patient-centered protocol specification reflecting the goal of the scan, an understanding of complex anatomy and pathophysiology, and particulars of CT scanner capabilities. In this paper, the need for new interventional approaches to mitral and tricuspid valve disease is discussed, followed by a detailed review of how to perform a high-quality CT angiography examination, taking into consideration scanner- and patient-specific variables when preparing a pre-mitral or tricuspid protocol. The many possible clinical challenges affecting the performance of cardiac and vascular CT angiography for pre-procedure mitral and tricuspid repair/replacement are reviewed and specific tips, trouble-shooting approaches, and recommendations are provided for how to conduct the best-quality study, be it at an experienced imaging center with the most advanced scanner or at a novice center using an earlier generation CT platform.

Practical considerations for optimizing cardiac computed tomography protocols for comprehensive acquisition prior to transcatheter aortic valve replacement.

Transcatheter aortic valve replacement (TAVR) is performed frequently in patients with severe, symptomatic aortic stenosis who are at high risk or inoperable for open surgical aortic valve replacement. Computed tomography angiography (CTA) has become the gold standard imaging modality for pre-TAVR cardiac anatomic and vascular access assessment. Traditionally, cardiac CTA has been most frequently used for assessment of coronary artery stenosis, and scanning protocols have generally been tailored for this purpose. Pre-TAVR CTA has different goals than coronary CTA and the high prevalence of chronic kidney disease in the TAVR patient population creates a particular need to optimize protocols for a reduction in iodinated contrast volume. This document reviews details which allow the physician to tailor CTA examinations to maximize image quality and minimize harm, while factoring in multiple patient and scanner variables which must be considered in customizing a pre-TAVR protocol.

Very low intravenous contrast volume protocol for computed tomography angiography providing comprehensive cardiac and vascular assessment prior to transcatheter aortic valve replacement in patients with chronic kidney disease.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a lifesaving procedure for many patients high risk for surgical aortic valve replacement. The prevalence of chronic kidney disease (CKD) is high in this population, and thus a very low contrast volume (VLCV) computed tomography angiography (CTA) protocol providing comprehensive cardiac and vascular imaging would be valuable. METHODS: 52 patients with severe, symptomatic aortic valve disease, undergoing pre-TAVR CTA assessment from 2013-4 at Columbia University Medical Center were studied, including all 26 patients with CKD (eGFR<30 mL/min) who underwent a novel VLCV protocol (20 mL of iohexol at 2.5 mL/s), and 26 standard-contrast-volume (SCV) protocol patients. Using a 320-slice volumetric scanner, the protocol included ECG-gated volume scanning of the aortic root followed by medium-pitch helical vascular scanning through the femoral arteries. Two experienced cardiologists performed aortic annulus and root measurements. Vascular image quality was assessed by two radiologists using a 4-point scale. RESULTS: VLCV patients had mean (±SD) age 86 ± 6.5, BMI 23.9 ± 3.4 kg/m(2) with 54% men; SCV patients age 83 ± 8.8, BMI 28.7 ± 5.3 kg/m(2), 65% men. There was excellent intra- and inter-observer agreement for annular and root measurements, and excellent agreement with 3D-transesophageal echocardiographic measurements. Both radiologists found diagnostic-quality vascular imaging in 96% of VLCV and 100% of SCV cases, with excellent inter-observer agreement. CONCLUSIONS: This study is the first of its kind to report the feasibility and reproducibility of measurements for a VLCV protocol for comprehensive pre-TAVR CTA. There was excellent agreement of cardiac measurements and almost all studies were diagnostic quality for vascular access assessment.