On the Implementation of a Post-Pandemic Deep Learning Algorithm Based on a Hybrid CT-Scan/X-ray Images Classification Applied to Pneumonia Categories.

The identification and characterization of lung diseases is one of the most interesting research topics in recent years. They require accurate and rapid diagnosis. Although lung imaging techniques have many advantages for disease diagnosis, the interpretation of medial lung images has always been a major problem for physicians and radiologists due to diagnostic errors. This has encouraged the use of modern artificial intelligence techniques such as deep learning. In this paper, a deep learning architecture based on EfficientNetB7, known as the most advanced architecture among convolutional networks, has been constructed for classification of medical X-ray and CT images of lungs into three classes namely: common pneumonia, coronavirus pneumonia and normal cases. In terms of accuracy, the proposed model is compared with recent pneumonia detection techniques. The results provided robust and consistent features to this system for pneumonia detection with predictive accuracy according to the three classes mentioned above for both imaging modalities: radiography at 99.81% and CT at 99.88%. This work implements an accurate computer-aided system for the analysis of radiographic and CT medical images. The results of the classification are promising and will certainly improve the diagnosis and decision making of lung diseases that keep appearing over time.

High Resolution Computed Tomography Manifestations in Covid-19 Suspected and Diagnosed Patients

Aim: To study the High Resolution Computed Tomography manifestations in the evaluation of COVID-19 suspected and diagnosed patients and study its correlation in respect to CT severity scoring with symptomology, comorbidities, lab parameters and oxygen requirement in the study group. Method(s): This was a descriptive study conducted between August 2020 to October 2022 at Dr D.Y. Patil Medical College, Hospital and Research Centre, Pune after taking necessary approval by the institutional scientific and ethics committee. 500 patients meeting the inclusion criteria for the study were included in the study after taking a written informed consent from all the patients. Result(s): A total of 500 study participants were included;of them 27% (n=133) were categorized as mild on the basis of CT severity score, 51% (n=257) were categorized as moderate and 78 participants (15.6%) were categorized as severe. Thirty two (6.4%) patients who were suspected for having COVID-19 infection and being diagnosed as COVID-19 positive on RTPCR tests showed normal HRCT scans. Our study group included 311 male and 189 female patients. Ground glass opacities were the. Most common typical CT chest manifestation in our study group seen in all of severe patients followed by 97.3% in moderate groups, 94.7% in mild group. Consolidation was seen in 55.1% of severe patients followed by 31.9% in moderate disease groups, 15.8% in mild group. Bilateral involvement of lung parenchyma on HRCT was more common and was seen to affect 84.8% (n=429) of total population there was a lower lobe preponderance in early and mild disease with the right lower lobe being the most common lobe being affected followed by the left lower lobe. In our study group, atypical findings of COVID 19 disease on HRCT were seen in 24 % (n=120) of total population. In our study groups, among the atypical findings pleural effusion is the most common atypical finding which was seen in 10.2% (n=51) of total study population followed by mediastinal lymphadenopathy which was seen in 9.2% (n=46) of total study population. The mean number of days since symptoms was highest for patients in severe disease category (7.3 days) followed by moderate group (5.3 days) and mild group (3.0 days). In our study oxygenation support was required for 64.1% of patients in severe group followed by 39.3% in moderate group and 6.8% in mild group. Conclusion(s): COVID 19 disease has had a significant negative impact on the healthcare system all across the world and CT imaging plays an important role in assessing disease severity and progression. Our study supports the use of HRCT in patients with COVID-19 infection, which could be used as a rapid and an effective gatekeeper to rule-out patients with a low likelihood of disease. Copyright © 2023 Ubiquity Press. All rights reserved.

Pulmonary Infections in People Living with HIV.

Despite the development of combination antiretroviral therapy (cART) infections continue to cause significant morbidity and mortality among people living with HIV (PLWH). Pulmonary infections with Streptococcus pneumoniae, Haemophilus influenza, and Staphylococcus aureus remain common. One-third of PLWH worldwide are infected with tuberculosis and the infection manifests at any stage of HIV infection. Fungal infection is usually confined to PLWH unaware of their HIV infection until immunosuppression is advanced or those choosing to discontinue cART. The importance of viral infections has diminished since wide availability of cART; however, mortality from COVID-19 in PLWH may remain greater than in the non-HIV population.

Pneumomediastinum: Radiological profile and associations of uncommon complication of COVID-19.

Introduction: Spontaneous pneumomediastinum is an uncommon complication of Corona Virus Disease (COVID)-19 presenting mostly in moderate to severe cases. Materials and Methods: This is a retrospective observational imaging and hospital data-based study done on 15 confirmed patients of COVID-19 who underwent high resolution computed tomography (HRCT) thorax at the Department of Radio-Diagnosis of a tertiary medical center in the Himalayan foothills. The clinico-radiological profile of the study group was assessed and it was aimed at finding the association of pneumomediastinum with the severity of lung changes. Results: A strong association of pneumomediastinum was observed with severe lung changes on HRCT thorax (n = 13, 87%, P < 0.00001). Dyspnea was the most common presenting factor. The mortality rate is high in mechanically intubated patients of pneumomediastinum with COVID-19 (75%). Conclusion: Pneumomediastinum is a complication of a severe COVID-19 disease spectrum. Along with severe lung parenchymal disease, systemic inflammation, systemic steroid therapy, comorbid state, and mechanical intubation, it is a part of the pool of poor prognostic factors. HRCT is essential for making a quick and comprehensive diagnosis, thereby, guiding the clinician for further management.

Automatic Deep-Learning Segmentation of Epicardial Adipose Tissue from Low-Dose Chest CT and Prognosis Impact on COVID-19.

BACKGROUND: To develop a deep-learning (DL) pipeline that allowed an automated segmentation of epicardial adipose tissue (EAT) from low-dose computed tomography (LDCT) and investigate the link between EAT and COVID-19 clinical outcomes. METHODS: This monocentric retrospective study included 353 patients: 95 for training, 20 for testing, and 238 for prognosis evaluation. EAT segmentation was obtained after thresholding on a manually segmented pericardial volume. The model was evaluated with Dice coefficient (DSC), inter-and intraobserver reproducibility, and clinical measures. Uni-and multi-variate analyzes were conducted to assess the prognosis value of the EAT volume, EAT extent, and lung lesion extent on clinical outcomes, including hospitalization, oxygen therapy, intensive care unit admission and death. RESULTS: The mean DSC for EAT volumes was 0.85 ± 0.05. For EAT volume, the mean absolute error was 11.7 ± 8.1 cm3 with a non-significant bias of -4.0 ± 13.9 cm3 and a correlation of 0.963 with the manual measures (p < 0.01). The multivariate model providing the higher AUC to predict adverse outcome include both EAT extent and lung lesion extent (AUC = 0.805). CONCLUSIONS: A DL algorithm was developed and evaluated to obtain reproducible and precise EAT segmentation on LDCT. EAT extent in association with lung lesion extent was associated with adverse clinical outcomes with an AUC = 0.805.

Chest X-rays findings in COVID 19 patients at a University Teaching Hospital - A descriptive study.

OBJECTIVE: To analyze Chest X-ray findings in COVID 19 positive patients, presented at corona filtration center, Benazir Bhutto Hospital Rawalpindi, based on CXR classification of British Society of Thoracic Imaging (BSTI). METHODS: In this study, all RT-PCR COVID-19 positive patients screened at corona filtration center, Benazir Bhutto hospital Rawalpindi from 20th March 2020 to 10th April 2020 were included. Mean age of the cohort with age range was calculated. Presenting complaints & Co-morbid were analyzed and tabulated in frequencies and percentages. Portable CXR findings were classified according to BSTI classification and documented in frequencies and percentages. RESULTS: Mean age of the patients was 44 years. Presenting complaints were cough 20 (67%), fever 18 (60%), shortness of breath 11 (37%), sore throat six (20%), loss of sense of taste and smell four(13%). Main co-morbid was hypertension six (20%). Two (7%) patients had normal and seven (23%) had classical COVID CXRs. 21 (70%) patients were in indeterminate group with only one (3%) having unilateral lung disease. Three (10%) patients had diffuse lung involvement and 18(60%) had peripheral lung involvement. Majority of patients 19 (63%), had bilateral middle and lower zonal involvement. CONCLUSIONS: In this study, COVID-19 CXRs generally manifested a spectrum of pure ground glass, mixed ground glass opacities to consolidation in bilateral peripheral middle and lower lung zones. BSTI CXR reporting classification of COVID-19 is valid in our patients with addition of middle zonal involvement in classical COVID-19 criteria as opposed to just lower zone involvement.

Clinical implications of microvascular CT scan signs in COVID-19 patients requiring invasive mechanical ventilation.

PURPOSE: COVID-19-related acute respiratory distress syndrome (ARDS) is characterized by the presence of signs of microvascular involvement at the CT scan, such as the vascular tree in bud (TIB) and the vascular enlargement pattern (VEP). Recent evidence suggests that TIB could be associated with an increased duration of invasive mechanical ventilation (IMV) and intensive care unit (ICU) stay. The primary objective of this study was to evaluate whether microvascular involvement signs could have a prognostic significance concerning liberation from IMV. MATERIAL AND METHODS: All the COVID-19 patients requiring IMV admitted to 16 Italian ICUs and having a lung CT scan recorded within 3 days from intubation were enrolled in this secondary analysis. Radiologic, clinical and biochemical data were collected. RESULTS: A total of 139 patients affected by COVID-19 related ARDS were enrolled. After grouping based on TIB or VEP detection, we found no differences in terms of duration of IMV and mortality. Extension of VEP and TIB was significantly correlated with ground-glass opacities (GGOs) and crazy paving pattern extension. A parenchymal extent over 50% of GGO and crazy paving pattern was more frequently observed among non-survivors, while a VEP and TIB extent involving 3 or more lobes was significantly more frequent in non-responders to prone positioning. CONCLUSIONS: The presence of early CT scan signs of microvascular involvement in COVID-19 patients does not appear to be associated with differences in duration of IMV and mortality. However, patients with a high extension of VEP and TIB may have a reduced oxygenation response to prone positioning. TRIAL REGISTRATION: NCT04411459.

Retrospective analysis of the application of CT scan in the emergency department to screen clinically asymptomatic COVID-19 before hospital admission.

BACKGROUND: The necessity to identify and isolate COVID-19 patients to avoid intrahospital cross infections is particularly felt as a challenge. Clinically occult SARS-CoV-2 infection among patients admitted to the hospital is always considered a risk during the pandemic. The aim of our study is to describe the application of CT scan to reveal unexpected COVID-19 in patients needing hospital admission. METHOD: In our emergency department, we prospectively enrolled adult patients needing hospital admission, without symptoms suspected of COVID-19, and showing negative reverse transcriptase-polymerase chain reaction (RT-PCR) swab test. CT scan was performed to diagnose clinically occult COVID-19 pneumonia. All the exams were read and discussed retrospectively by two expert radiologists and assigned to one of 4 exclusive diagnoses: typical (typCT), indeterminate (indCT), atypical (atyCT), negative (negCT). The clinical characteristics and final diagnoses were described and compared with the results of CT scans. RESULTS: From May 25 to August 18, 2020, we prospectively enrolled 197 patients. They showed 122 negCT, 52 atyCT, 22 indCT, and 1 typCT. Based on the CT imaging, the prevalence of suspected clinically occult COVID-19 pneumonia was 11.6% (23 patients). None had confirmation of SARS-CoV-2 infection after the hospital stay. Nineteen patients had negative serial RT-PCR while in 4 cases, the infection was excluded by clinical follow-up or appearance of positivity of RT-PCR after months. CONCLUSION: Our descriptive analysis confirms that CT scan cannot be considered a valid tool to screen clinically occult COVID-19, when the asymptomatic patients need hospitalization for other conditions. Application of personnel protections and distancing among patients remains the best strategies to limit the possibility of intrahospital cross-infections.

An overview of the National COVID-19 Chest Imaging Database: data quality and cohort analysis.

BACKGROUND: The National COVID-19 Chest Imaging Database (NCCID) is a centralized database containing mainly chest X-rays and computed tomography scans from patients across the UK. The objective of the initiative is to support a better understanding of the coronavirus SARS-CoV-2 disease (COVID-19) and the development of machine learning technologies that will improve care for patients hospitalized with a severe COVID-19 infection. This article introduces the training dataset, including a snapshot analysis covering the completeness of clinical data, and availability of image data for the various use-cases (diagnosis, prognosis, longitudinal risk). An additional cohort analysis measures how well the NCCID represents the wider COVID-19-affected UK population in terms of geographic, demographic, and temporal coverage. FINDINGS: The NCCID offers high-quality DICOM images acquired across a variety of imaging machinery; multiple time points including historical images are available for a subset of patients. This volume and variety make the database well suited to development of diagnostic/prognostic models for COVID-associated respiratory conditions. Historical images and clinical data may aid long-term risk stratification, particularly as availability of comorbidity data increases through linkage to other resources. The cohort analysis revealed good alignment to general UK COVID-19 statistics for some categories, e.g., sex, whilst identifying areas for improvements to data collection methods, particularly geographic coverage. CONCLUSION: The NCCID is a growing resource that provides researchers with a large, high-quality database that can be leveraged both to support the response to the COVID-19 pandemic and as a test bed for building clinically viable medical imaging models.

Thoracic imaging outcomes in COVID-19 survivors.

The coronavirus disease 2019 (COVID-19) pandemic presents a significant global public health challenge. One in five individuals with COVID-19 presents with symptoms that last for weeks after hospital discharge, a condition termed "long COVID". Thus, efficient follow-up of patients is needed to assess the resolution of lung pathologies and systemic involvement. Thoracic imaging is multimodal and involves using different forms of waves to produce images of the organs within the thorax. In general, it includes chest X-ray, computed tomography, lung ultrasound and magnetic resonance imaging techniques. Such modalities have been useful in the diagnosis and prognosis of COVID-19. These tools have also allowed for the follow-up and assessment of long COVID. This review provides insights on the effectiveness of thoracic imaging techniques in the follow-up of COVID-19 survivors who had long COVID.

Chest radiograph in hospitalized children with COVID-19. A review of findings and indications.

PURPOSE: Many articles have been published regarding chest-imaging in COVID-19, but fewer studies have been published in pediatric populations. COVID-19 symptoms in children are generally milder and radiological tests have fewer positive findings. Indications for chest imaging in pediatric COVID-19 patients remain unclear. This study aims to describe the chest radiographs performed in COVID-19 patients in a pediatric hospital, to review the current chest X-ray indications and to develop an specific age-adjusted protocol for chest-imaging in children with COVID-19. METHODS: Retrospective study in hospitalized pediatric COVID-19 patients in Navarre, Spain. Between March and December 2020, 44 children were included (mean age 3.8-year-old, 50 % males). Demographic information, cause of admission, symptoms, and clinical evolution were described. Chest imaging technique performed, indications and findings were analyzed. A literature review was performed searching for current COVID-19 pediatric chest-imaging indications. RESULTS: Chest X-rays were performed in 35 patients (80 % of admissions) and most common indications were fever and respiratory symptoms. 53 % of the chest X-rays were considered "normal" and the classical bilateral diffuse interstitial pattern, described in adults, was only present in 22 %. All patients with pathological chest X-rays were symptomatic and reported fever (100 %) and fever tended to be longer (fever duration: 4.25 vs. 2.46 days p:0.048) in patients with pathological radiographs. We present a specific protocol for chest-imaging in pediatric COVID-19 cases. CONCLUSIONS: COVID-19 clinical manifestations and radiological findings are milder and less specific in children. Imaging should not be used as a screening tool or a routine complementary test in pediatric COVID-19 patients, not even in hospitalized cases.

Imaging algorithm for COVID-19: A practical approach.

The global pandemic of COVID-19 pneumonia caused by the novel coronavirus (SARS-CoV-2) has strained healthcare resources across the world with emerging challenges of mass testing, resource allocation and management. While reverse transcriptase-polymerase chain reaction (RT-PCR) test is the most commonly utilized test and considered the current gold standard for diagnosis, the role of chest imaging has been highlighted by several studies demonstrating high sensitivity of computed tomography (CT). Many have suggested using CT chest as a first-line screening tool for the diagnosis of COVID-19. However, with advancement of laboratory testing and challenges in obtaining a CT scan without significant risk to healthcare providers, the role of imaging in diagnosis has been questioned. Several imaging societies have released consensus statements and guidelines on utilizing imaging resources and optimal reporting. In this review, we highlight the current evidence on various modalities in thoracic imaging for the diagnosis of COVID-19 and describe an algorithm on how to use these resources in an optimal fashion in accordance with the guidelines and statements released by major imaging societies.

Where COVID-19 testing is challenging: a case series highlighting the role of thoracic imaging in resolving management dilemma posed by unusual presentation.

The COVID-19 pandemic remains an evolving disease posing a challenge of incomplete understanding escalated by random atypical clinical presentations. Numerous challenges still exist with accessibility and availability of standard COVID-19 viral testing using real-time Polymerase Chain Reaction (RT-PCR), in low- and middle-income countries, especially in several hospital settings. The clinical information of three select patients at a major health facility in Southwestern Nigeria with unusual COVID-19 clinical presentation and clinical management dilemma related to challenges with COVID-19 viral laboratory testing, were retrospectively reviewed. The medical history in all three cases closely mimicked that of other medical conditions because of assumptions created by red herrings like an acute exacerbation of an underlying non-communicable disease (diaphragmatic eventration) in case 1, re-activation of a previously treated lung condition (tuberculosis) in case 2 and a sequalae of a previously diagnosed but poorly-managed chronic non-communicable disease (decompensated hypertensive heart disease). Also, viral testing was challenging in all cases due to reasons ranging from late turn-around time to inconsistent results. However, thoracic imaging was employed in all cases to heighten suspicion of COVID-19 infection, resolve management dilemma and limit intra-hospital spread. Thoracic imaging can play a major role within hospital settings in low-and middle-income countries in resolving diagnostic challenges of atypical COVID-19 clinical presentations, raising suspicion for early institution of intra-hospital disease containment measures, limiting exposure among hospital staff and guiding clinical case management of COVID-19; especially where challenges with confirmatory viral testing remain persistent.

CT Findings in Negative Pressure Pulmonary Edema.

Negative pressure pulmonary edema (NPPE) is a rare, potentially life-threatening, and yet diagnostically challenging perioperative complication. Most cases of NPPE occur in the context of anesthetic procedures, mainly caused by upper airway obstruction, and are diagnosed during the recovery period. We present a case of fulminant NPPE in a patient during general anesthesia which illustrates the eye-catching CT findings that can occur in NPPE and eventually support diagnosis. With regard to the current pandemic, we include a discussion of the typical imaging patterns of COVID-19 as a radiological differential diagnosis of NPPE. A 42-year old male patient presented with sudden respiratory insufficiency during arthroscopic knee lavage and subsequently required highly invasive ventilation therapy and catecholamine administration. Postoperative CT imaging of the thorax exhibited extensive, centrally accentuated consolidations with surrounding ground-glass opacity in all lung lobes, suggestive of pulmonary edema. In view of the clinical course and the imaging findings, a negative pressure pulmonary edema (NPPE) was diagnosed.

Pediatric chest x-ray in covid-19 infection.

BACKGROUND: The outbreak of COVID-19 has become pandemic. Pediatric population has been less studied than adult population and prompt diagnosis is challenging due to asymptomatic or mild episodes. Radiology is an important complement to clinical and epidemiological features. OBJECTIVE: To establish the most common CXR patterns in children with COVID-19, evaluate interobserver correlation and to discuss the role of imaging techniques in the management of children. MATERIALS AND METHODS: Forty-four patients between 0 and 16 years of age with confirmed SARS-Cov-2 infection and CXR were selected. Two paediatric radiologists independently evaluated the images and assessed the type of abnormality, distribution and evolution when available. RESULTS: Median age was 79.8 months (ranging from 2 weeks to 16 years of age). Fever was the most common symptom (43.5 %). 90 % of CXR showed abnormalities. Peribronchial cuffing was the most common finding (86.3 %) followed by GGOs (50 %). In both cases central distribution was more common than peripheral. Consolidations accounted for 18.1 %. Normal CXR, pleural effusion, and altered cardiomediastinal contour were the least common. CONCLUSION: The vast majority of CXR showed abnormalities in children with COVID-19. However, findings are nonspecific. Interobserver correlation was good in describing consolidations, normal x-rays and GGOs. Imaging techniques have a role in the management of children with known or suspected COVID-19, especially in those with moderate or severe symptoms or with underlying risk factors.

Pulmonary Angiopathy in Severe COVID-19: Physiologic, Imaging, and Hematologic Observations.

Rationale: Clinical and epidemiologic data in coronavirus disease (COVID-19) have accrued rapidly since the outbreak, but few address the underlying pathophysiology.Objectives: To ascertain the physiologic, hematologic, and imaging basis of lung injury in severe COVID-19 pneumonia.Methods: Clinical, physiologic, and laboratory data were collated. Radiologic (computed tomography (CT) pulmonary angiography [n = 39] and dual-energy CT [DECT, n = 20]) studies were evaluated: observers quantified CT patterns (including the extent of abnormal lung and the presence and extent of dilated peripheral vessels) and perfusion defects on DECT. Coagulation status was assessed using thromboelastography.Measurements and Results: In 39 consecutive patients (male:female, 32:7; mean age, 53 ± 10 yr [range, 29-79 yr]; Black and minority ethnic, n = 25 [64%]), there was a significant vascular perfusion abnormality and increased physiologic dead space (dynamic compliance, 33.7 ± 14.7 ml/cm H2O; Murray lung injury score, 3.14 ± 0.53; mean ventilatory ratios, 2.6 ± 0.8) with evidence of hypercoagulability and fibrinolytic "shutdown". The mean CT extent (±SD) of normally aerated lung, ground-glass opacification, and dense parenchymal opacification were 23.5 ± 16.7%, 36.3 ± 24.7%, and 42.7 ± 27.1%, respectively. Dilated peripheral vessels were present in 21/33 (63.6%) patients with at least two assessable lobes (including 10/21 [47.6%] with no evidence of acute pulmonary emboli). Perfusion defects on DECT (assessable in 18/20 [90%]) were present in all patients (wedge-shaped, n = 3; mottled, n = 9; mixed pattern, n = 6).Conclusions: Physiologic, hematologic, and imaging data show not only the presence of a hypercoagulable phenotype in severe COVID-19 pneumonia but also markedly impaired pulmonary perfusion likely caused by pulmonary angiopathy and thrombosis.