Bringing MRI to low- and middle-income countries: Directions, challenges and potential solutions.

The global disparity of magnetic resonance imaging (MRI) is a major challenge, with many low- and middle-income countries (LMICs) experiencing limited access to MRI. The reasons for limited access are technological, economic and social. With the advancement of MRI technology, we explore why these challenges still prevail, highlighting the importance of MRI as the epidemiology of disease changes in LMICs. In this paper, we establish a framework to develop MRI with these challenges in mind and discuss the different aspects of MRI development, including maximising image quality using cost-effective components, integrating local technology and infrastructure and implementing sustainable practices. We also highlight the current solutions-including teleradiology, artificial intelligence and doctor and patient education strategies-and how these might be further improved to achieve greater access to MRI.

MRI fat fraction imaging of nodal and bone metastases in prostate cancer.

KEY POINTS: • Characterisation and quantification of tissue fat on MRI can be used to provide information on disease processes. • Fat in bone and lymph nodes up until recently have not been exploited for diagnostic purposes or response monitoring in prostate cancer. • Fat imaging on MRI using Dixon/PDFF sequences has the potential to add clinical value in the future but prospective data is needed.

Troponin and short-term mortality in hospitalised patients with COVID-19 infection: a retrospective study in an inner-city London hospital.

OBJECTIVE: To investigate the association between troponin positivity in patients hospitalised with COVID-19 and increased mortality in the short term. SETTING: Homerton University Hospital, an inner-city district general hospital in East London. DESIGN: A single-centre retrospective observational study. PARTICIPANTS: All adults admitted with swab-proven RT-PCR COVID-19 to Homerton University Hospital from 4 February 2020 to 30 April 2020 (n=402). OUTCOME MEASURES: We analysed demographic and biochemical data collected from the patient record according to the primary outcome of death at 28 days during hospital admission. METHODS: Troponin positivity was defined above the upper limit of normal according to our local laboratory assay (>15.5 ng/L for females, >34 ng/L for males). Univariate and multivariate logistical regression analyses were performed to evaluate the link between troponin positivity and death. RESULTS: Mean age was 65.3 years for men compared with 63.8 years for women. A χ2 test showed survival of patients with COVID-19 was significantly higher in those with a negative troponin (p=3.23×10-10) compared with those with a positive troponin. In the multivariate logistical regression, lung disease, age, troponin positivity and continuous positive airway pressure were all significantly associated with death, with an area under the curve of 0.889, sensitivity of 0.886 and specificity of 0.629 for the model. Within this model, troponin positivity was independently associated with short-term mortality (OR 2.97, 95% CI 1.34 to 6.61, p=0.008). CONCLUSIONS: We demonstrated an independent association between troponin positivity and increased short-term mortality in COVID-19 in a London district general hospital.

Sustainable low-field cardiovascular magnetic resonance in changing healthcare systems.

Cardiovascular disease continues to be a major burden facing healthcare systems worldwide. In the developed world, cardiovascular magnetic resonance (CMR) is a well-established non-invasive imaging modality in the diagnosis of cardiovascular disease. However, there is significant global inequality in availability and access to CMR due to its high cost, technical demands as well as existing disparities in healthcare and technical infrastructures across high-income and low-income countries. Recent renewed interest in low-field CMR has been spurred by the clinical need to provide sustainable imaging technology capable of yielding diagnosticquality images whilst also being tailored to the local populations and healthcare ecosystems. This review aims to evaluate the technical, practical and cost considerations of low field CMR whilst also exploring the key barriers to implementing sustainable MRI in both the developing and developed world.