Computer-aided diagnosis for World Health Organization-defined chest radiograph primary-endpoint pneumonia in children.

BACKGROUND: The chest radiograph is the most common imaging modality to assess childhood pneumonia. It has been used in epidemiological and vaccine efficacy/effectiveness studies on childhood pneumonia. OBJECTIVE: To develop computer-aided diagnosis (CAD4Kids) for chest radiography in children and to evaluate its accuracy in identifying World Health Organization (WHO)-defined chest radiograph primary-endpoint pneumonia compared to a consensus interpretation. MATERIALS AND METHODS: Chest radiographs were independently evaluated by three radiologists based on WHO criteria. Automatic lung field segmentation was followed by manual inspection and correction, training, feature extraction and classification. Radiographs were filtered with Gaussian derivatives on multiple scales, extracting texture features to classify each pixel in the lung region. To obtain an image score, the 95th percentile score of the pixels was used. Training and testing were done in 10-fold cross validation. RESULTS: The radiologist majority consensus reading of 858 interpretable chest radiographs included 333 (39%) categorised as primary-endpoint pneumonia, 208 (24%) as other infiltrate only and 317 (37%) as no primary-endpoint pneumonia or other infiltrate. Compared to the reference radiologist consensus reading, CAD4Kids had an area under the receiver operator characteristic (ROC) curve of 0.850 (95% confidence interval [CI] 0.823-0.876), with a sensitivity of 76% and specificity of 80% for identifying primary-endpoint pneumonia on chest radiograph. Furthermore, the ROC curve was 0.810 (95% CI 0.772-0.846) for CAD4Kids identifying primary-endpoint pneumonia compared to other infiltrate only. CONCLUSION: Further development of the CAD4Kids software and validation in multicentre studies are important for future research on computer-aided diagnosis and artificial intelligence in paediatric radiology.

Calcinosis circumscripta of the breasts: The deeper meaning.

Calcinosis circumscripta involving the breasts usually hints at an underlying systemic cause, most commonly connective tissue disorders such as scleroderma or dermatomyositis. Localised scleroderma, also known as morphoea, is not usually associated with the systemic anomalies affecting the lungs and gastrointestinal system, but does manifest as calcified dermal and subdermal sclerotic plaques. Histological confirmation with skin biopsy is diagnostic. Contribution: Recognition of the atypical, bizarre, linear dystrophic calcifications on mammography should direct appropriate systemic investigations.

Chest radiography evaluation in patients admitted with confirmed COVID-19 infection, in a resource limited South African isolation hospital.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the subsequent global outbreak (coronavirus disease 2019 [COVID-19]) was declared a public health emergency in January 2020. Recent radiologic literature regarding COVID-19 has primarily focused on Computed Tomography (CT) chest findings, with chest radiography lacking in comparison. OBJECTIVES: To describe the demographic profile of adult patients with COVID-19 pneumonia requiring hospital admission. To describe and quantify the imaging spectrum on chest radiography using a severity index, and to correlate the severity of disease with prognosis. METHOD: Retrospective review of chest radiographs and laboratory records in patients admitted to a South African tertiary hospital with confirmed COVID-19 infection. The chest X-rays were systematically reviewed for several radiographic features, which were then quantified using the Brixia scoring system, and correlated to the patient's outcome. RESULTS: A total of 175 patients (mean age: 53.34 years) admitted with COVID-19 were included. Ground glass opacification (98.9%), consolidation (86.3%), and pleural effusion (29.1%) was commonly found. Involvement of bilateral lung fields (96.6%) with no zonal predominance (61.7%), was most prevalent. Correlation between the Brixia score and outcome was found between severe disease and death (odds ratio [OR]: 12.86; 95% confidence interval [CI]: 1.58-104.61). Many patients had unknown TB (71.4%) and HIV (72.6%) statuses. CONCLUSION: In this study population, ground glass opacification, consolidation, and pleural effusions, with bilateral lung involvement and no zonal predominance were the most prevalent findings in proven COVID-19 infection. Quantification using the Brixia scoring system may assist with timeous assessment of disease severity in COVID-19 positive patients, as an overall predicator of clinical outcome.

Prevalence of incidental premature cardiac calcifications in an HIV-infected South African population using conventional computed tomography chest radiography.

BACKGROUND: International literature reported an increased prevalence of cardiovascular disease in persons living with HIV (PLWH), inferring an association with accelerated coronary atherosclerosis and plaque formation. Few local studies of HIV-related cardiac disease have confirmed this. Early identification of cardiac plaques would assist clinicians with risk stratification and implementation of treatment strategies to reduce morbidity and mortality. In resource-limited settings the use of conventional computed tomography (CT) may have a role in identifying at-risk individuals. OBJECTIVES: This hypothesis-generating study was aimed at determining the contribution of HIV to accelerated vascular aging by assessing cardiac calcifications, incidentally detected on conventional CT chest imaging, in a young HIV-positive population. METHOD: A retrospective quantitative analysis was performed at a tertiary hospital in KwaZulu-Natal, South Africa, over a 5-year period. Young patients (18-45 years) who underwent CT chest imaging for varied indications were included, further sub-categorised by immune status, the presence, absence and location of calcifications. Patients with unknown HIV statuses were excluded. RESULTS: An increased probability of cardiac calcification with increasing age, independent of the HIV status, was established. No statistically significant difference could be demonstrated between the cohorts. In the pre-contrasted subcategory, a lower P-value suggested an 'imminent' statistical significance. Contrast may have obscured some calcifications. The failure to record the immune status in a large number of patients resulted in their exclusion and limited the study. CONCLUSION: The increased prevalence of incidentally detected cardiac calcifications in young HIV-infected individuals warrants further evaluation and cardiovascular risk stratification.

Solid to cystic: A case report of imaging findings of atypical lung metastases.

The imaging spectrum of pulmonary metastases varies greatly, with solid and partly cavitating nodules being the most common. When imaging the oncology patient, specifically follow-up imaging post-treatment, the radiological aim is to assess for disease regression and thus treatment response, usually with resolution of these nodules. We report an interesting case series of a patient with primary endometrial carcinoma presenting with pulmonary metastases. This imaging series eloquently depicts the temporal evolution of the metastatic solid pulmonary nodules to cavitating nodules and finally to thin-walled cysts. Baseline imaging in this scenario is vital to exclude pre-existing cystic lung disease. The progression of solid pulmonary metastases to simple cysts is an uncommon therapy-related consequence, but an important entity to recognise, not only as an indicator of good treatment response, but also to evaluate for potential life-threatening complications such as spontaneous pneumothoraces.

Chest radiography evaluation in patients admitted with confirmed COVID-19 infection, in a resource limited South African isolation hospital

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the subsequent global outbreak (coronavirus disease 2019 [COVID-19]) was declared a public health emergency in January 2020. Recent radiologic literature regarding COVID-19 has primarily focused on Computed Tomography (CT) chest findings, with chest radiography lacking in comparison. Objectives: To describe the demographic profile of adult patients with COVID-19 pneumonia requiring hospital admission. To describe and quantify the imaging spectrum on chest radiography using a severity index, and to correlate the severity of disease with prognosis. Method: Retrospective review of chest radiographs and laboratory records in patients admitted to a South African tertiary hospital with confirmed COVID-19 infection. The chest X-rays were systematically reviewed for several radiographic features, which were then quantified using the Brixia scoring system, and correlated to the patient's outcome. Results: A total of 175 patients (mean age: 53.34 years) admitted with COVID-19 were included. Ground glass opacification (98.9%), consolidation (86.3%), and pleural effusion (29.1%) was commonly found. Involvement of bilateral lung fields (96.6%) with no zonal predominance (61.7%), was most prevalent. Correlation between the Brixia score and outcome was found between severe disease and death (odds ratio [OR]: 12.86; 95% confidence interval [CI]: 1.58­104.61). Many patients had unknown TB (71.4%) and HIV (72.6%) statuses. Conclusion: In this study population, ground glass opacification, consolidation, and pleural effusions, with bilateral lung involvement and no zonal predominance were the most prevalent findings in proven COVID-19 infection. Quantification using the Brixia scoring system may assist with timeous assessment of disease severity in COVID-19 positive patients, as an overall predicator of clinical outcome.