Quality assurance of paediatric lateral chest radiographs.

INTRODUCTION: Lateral chest radiographs aid in paediatric clinical practice in countries where the diagnosis of primary pulmonary tuberculosis (PTB) still relies heavily on the chest radiograph. This study aimed to create a validated quality assurance (QA) tool investigating the diagnostic performance of this projection by applying this to a database of lateral chest radiographs in children with suspected PTB. METHOD: The QA tool was built to include a compilation of criteria from the different sources, accompanied by graphic representations and objective measurements where appropriate. Each defined criterion (radiographic error) was evaluated by implementing the QA tool on 300 radiographs, scored by three readers. The sample was subjected to two separate sets of data analysis, based on averages, and on majority decision methodology. RESULTS: The QA tool was based on existing published criteria, as well as under-collimation and under-inspiration, two de novo criteria. For the total 900 reads, errors were categorized as patient-related in 681 (75.7%) and radiographer-related in 421 (46.8%) and 122 (13.6%) had no errors. The average number of errors per radiograph ranged from 0.9 to 4.7 errors out of the 11 quality factors reviewed. When considering the majority decision, the median errors per radiograph was 1 (IQR 1-2) (range 0-5). Inter-rater agreement varied for different criteria. CONCLUSION: A novel QA tool for evaluating lateral chest radiographs was developed which requires further efforts of refinement regarding criteria such as exposure, field of view: under-collimation, and motion artifact, which remain subjective. The designed QA tool will allow comparison of radiograph quality before and after interventions. Furthermore, the tool can be used in tackling childhood PTB in low- and middle-income countries (LMICs) since the hallmark of the disease is lymphadenopathy, which is often depicted best on lateral chest radiographs.

Optic neuritis: A South African hospital-based prospective study protocol.

BACKGROUND: Optic neuritis is a relatively common disease with an estimated lifetime risk of 0.6 per 1000; the estimated prevalence is 1-5 per 100 000/year. It occurs because of inflammation of the optic nerve from a variety of causes. The diagnosis of the disorder is established clinically and current literature is predominantly based on white patients from high-income countries. Optic neuritis presents differently in black patients compared to white patients. This study aims to assess the presentation and outcome of optic neuritis patients in a South African setting. METHODS: This is a prospective, hospital-based cohort study that will enrol patients with optic neuritis presenting to either the neurology department at Chris Hani Baragwanath Academic Hospital or the ophthalmology department at St John Eye Hospital, both in Johannesburg, South Africa. The specific aetiologies, clinical presentation and radiological findings will be studied, and the patient's course over one year will be documented in three-monthly follow-up visits. A specific group of patients with Neuromyelitis Optica Spectrum Disorders (NMOSD) and Myelin Oligodendrocyte Glycoprotein Associated Disorders (MOGAD) optic neuritis will be followed up for 5 years at yearly intervals. DISCUSSION: This study represents one of the few cohort studies in Sub-Saharan Africa that seeks to investigate optic neuritis. Our hope is that it will lead to better insights regarding the presentation, course and outcome of this condition. We will also analyse the data with a view of developing a predictive model for good visual outcome.

CT pulmonary angiography findings in HIV-infected patients referred for suspected pulmonary thrombo-embolic disease.

BACKGROUND: South Africa bares a significant burden of HIV and imaging is commonly performed as part of the workup for respiratory distress. OBJECTIVES: The aim of this study was to document the prevalence of pulmonary thrombo-embolic disease (PTED) and other findings in HIV-infected patients referred for CT pulmonary angiography (CTPA) for suspected PTED. METHOD: Forty CTPA studies of documented HIV-infected individuals investigated for suspected PTED during a 1-year period were retrieved, anonymised and interpreted by three consultant radiologists. Inter-reader reliability was calculated using Free Marginal multi-rater Kappa. RESULTS: Fourteen of the forty cases (35%) were positive for PTED. In the pulmonary embolism (PE)-positive group, 57.14% had peripheral disease and 42.86% had both peripheral and central disease. Associated findings in the PE-positive cases were pulmonary infarcts (17.5%), mosaic attenuation (17.5%) and linear atelectasis (7.5%). The most common incidental findings were solid pulmonary nodules (52.5%), non-wedge-shaped consolidation (45%), cardiomegaly (52.5%) and enlarged intra-thoracic lymph nodes (52.5%). Thirty per cent of the study population had findings related directly to the presence of PTED, whilst most cases in the study (77.5%) had pulmonary findings unrelated to PTED. In the PE-negative cases, 55% reported emergent findings that warranted immediate or urgent medical attention. CONCLUSION: Computed tomography pulmonary angiography imaging is critical for diagnosing PE. However, further investigation into the judicious application of CTPA in HIV-infected patients with suspected PTED is required, as CTPA findings in most of the cases in this study were unrelated to PE.