INTRODUCTION: Chest radiographs (CXRs) are widely used for the screening and management of COVID-19. This article describes the radiographic features of COVID-19 based on an initial national cohort of patients. METHODS: This is a retrospective review of swab-positive patients with COVID-19 who were admitted to four different hospitals in Singapore between 22 January and 9 March 2020. Initial and follow-up CXRs were reviewed by three experienced radiologists to identify the predominant pattern and distribution of lung parenchymal abnormalities. RESULTS: In total, 347 CXRs of 96 patients were reviewed. Initial CXRs were abnormal in 41 (42.7%) out of 96 patients. The mean time from onset of symptoms to CXR abnormality was 5.3 ± 4.7 days. The predominant pattern of lung abnormality was ground-glass opacity on initial CXRs (51.2%) and consolidation on follow-up CXRs (51.0%). Multifocal bilateral abnormalities in mixed central and peripheral distribution were observed in 63.4% and 59.2% of abnormal initial and follow-up CXRs, respectively. The lower zones were involved in 90.2% of initial CXRs and 93.9% of follow-up CXRs. CONCLUSION In a cohort of swab-positive patients, including those identified from contact tracing, we found a lower incidence of CXR abnormalities than was previously reported. The most common pattern was ground-glass opacity or consolidation, but mixed central and peripheral involvement was more common than peripheral involvement alone.
COVID-19 ; Humans ; Lung/diagnostic imaging* ; Radiography, Thoracic ; Retrospective Studies ; SARS-CoV-2 ; Singapore

Betacoronavirus ; Coronavirus Infections ; diagnosis ; Diagnosis, Differential ; Diagnostic Imaging ; methods ; Humans ; Male ; Middle Aged ; Pandemics ; Pneumonia, Viral ; diagnosis ; virology ; Radiography, Thoracic ; methods ; Tomography, X-Ray Computed ; methods

Lung cancer is the leading cause of cancer-related death around the world, being the top cause of cancer-related deaths among men and the second most common cause of cancer-related deaths among women in Singapore. Currently, no screening programme for lung cancer exists in Singapore. Since there is mounting evidence indicating a different epidemiology of lung cancer in Asian countries, including Singapore, compared to the rest of the world, a unique and adaptive approach must be taken for a screening programme to be successful at reducing mortality while maintaining cost-effectiveness and a favourable risk-benefit ratio. This review article promotes the use of low-dose computed tomography of the chest and explores the radiological challenges and future directions.

Artificial intelligence (AI) has been positioned as being the most important recent advancement in radiology, if not the most potentially disruptive. Singapore radiologists have been quick to embrace this technology as part of the natural progression of the discipline toward a vision of how clinical medicine, empowered by technology, can achieve our national healthcare objectives of delivering value-based and patient-centric care. In this article, we consider 3 core questions relating to AI in radiology, and review the barriers to the widespread adoption of AI in radiology. We propose solutions and describe a "Centaur" model as a promising avenue for enabling the interfacing between AI and radiologists. Finally, we introduce The Radiological AI, Data Science and Imaging Informatics (RADII) subsection of the Singapore Radiological Society. RADII is an enabling body, which together with key technological and institutional stakeholders, will champion research, development and evaluation of AI for radiology applications.
Artificial Intelligence ; Humans ; Image Processing, Computer-Assisted ; Machine Learning ; Neural Networks (Computer) ; Radiology ; Singapore ; Societies, Medical

INTRODUCTIONThis study aimed to assess the accuracy and outcomes of coronary computed tomography angiography (CCTA) performed in a regional hospital in Singapore.

METHODSThe Changi General Hospital CCTA database was retrospectively analysed over a 24-month period. Electronic hospital records, catheter coronary angiography (CCA) and CCTA electronic databases were used to gather data on major adverse cardiovascular events (MACE) and CCA results. CCTA findings were deemed positive if coronary artery stenosis ≥ 50% was reported or if the stenosis was classified as moderate or severe. CCA findings were considered positive if coronary artery stenosis ≥ 50% was reported.

RESULTSThe database query returned 679 patients who had undergone CCTA for the evaluation of suspected coronary artery disease. Of the 101 patients in the per-patient accuracy analysis group, there were six true negatives, one false negative, 81 true positives and 13 false positives, resulting in a negative predictive value of 85.7% and positive predictive value of 86.2%. The mean age of the study sample was 53 ± 13 years and 255 (37.6%) patients were female. Mean duration of patient follow-up was 360 days. Of the 513 negative CCTA patients, none developed MACE during the follow-up period, and of the 164 positive CCTA patients, 19 (11.6%) developed MACE (p < 0.001).

CONCLUSIONAnalysis of CCTA studies suggested accuracy and outcomes that were consistent with published clinical data. There was a one-year MACE-free warranty period following negative CCTA findings.

A 77-year-old man presented with acute-onset severe chest pain radiating to the back and elevated blood pressure. Multiphasic computed tomography of the aorta revealed an intimal tear in the descending thoracic aorta which extended both retrograde to the aortic root and antegrade to the infra-renal abdominal aorta. The initial impression, that the images showed a Stanford type B aortic dissection, was because the portion of the false lumen that extended beyond the aortic arch remained unopacified even on delayed phases, making it challenging to assess the extent of the dissection flap. Bedside transthoracic echocardiography revealed a pericardial effusion. Cardiac tamponade ensued and the patient passed away shortly after presentation. This case highlights the need for early and accurate imaging assessment of acute aortic dissection, including accurate identification of the site of intimal tear and the extent of the dissection flap.

Colorectal carcinoma is a common lethal disease with signs and symptoms that may be nonspecific. Computed tomography (CT) of the abdomen and pelvis with or without contrast is frequently performed for various general abdominal complaints, but unlike CT colonography, the large bowel may not be optimally prepared for evaluation. As such, careful and diligent assessment of the non-prepared colon in all CT images of the abdomen and pelvis is important, as it ensures that incidental colorectal malignancy is not missed, especially in older patients. This article gives an overview of multidetector CT imaging signs and subtle clues to aid in the diagnosis of colorectal carcinoma, as well as their pitfalls.
Colonic Polyps ; pathology ; Colonography, Computed Tomographic ; Colorectal Neoplasms ; diagnosis ; diagnostic imaging ; Diagnosis, Differential ; Humans ; Incidental Findings ; Pelvis ; diagnostic imaging ; Radiography, Abdominal ; Tomography, X-Ray Computed

INTRODUCTIONThe 'DOT & Shop' scheme is sponsored by SATA CommHealth, a local non-governmental organisation. It was launched in July 2009, in collaboration with Singapore's Tuberculosis Control Unit (TBCU). Under this scheme, grocery vouchers are disbursed to low-income patients with tuberculosis (TB) at each clinic visit if they have been adherent to directly observed therapy (DOT). This study aimed to determine the effect of this incentive scheme on treatment completion rates and to report the characteristics of patients who were non-adherent to the scheme.

METHODSThis descriptive study used data from the TBCU medical social worker database and the National TB Registry.

RESULTSFrom July 2009 to December 2012, a total of 883 TB patients were enrolled in the scheme. The overall treatment completion rates of the patients before (July 2006-June 2009) and after (July 2009-December 2012) the implementation of the scheme improved from 85.3% to 87.2% (p = 0.02). Patients under this scheme had a higher treatment completion rate (90.0%) than those not under this scheme (86.4%) (p < 0.01). It was found that the non-adherent patients were more likely to be of Malay ethnicity, younger and unemployed.

CONCLUSIONWe demonstrate the salutary effect of a non-governmental organisation-funded grocery voucher incentive scheme for low-income TB patients on DOT in Singapore.

Adult ; Age Factors ; Aged ; Antitubercular Agents ; therapeutic use ; Databases, Factual ; Directly Observed Therapy ; methods ; Female ; Food Assistance ; Humans ; Male ; Middle Aged ; Motivation ; Patient Compliance ; Poverty ; Program Evaluation ; Singapore ; Tuberculosis ; drug therapy ; Unemployment

INTRODUCTIONIn end-stage heart failure (HF) that is not eligible for mechanical assist device or heart transplant, palliative care serves to maximise symptom control and quality of life. We sought to evaluate the impact of home-based advance care programme (ACP) on healthcare utilisation in end-stage HF patients.

MATERIALS AND METHODSProspectively collected registry data on all end-stage HF recruited into ACP between July 2008 and July 2010 were analysed. Chart reviews were conducted on HF database and hospital electronic records. Phone interview and home visit details by ACP team were extracted to complete data entry. HF and all-cause hospitalisations 1 year before, and any time after ACP inception were defined as events. For the latter analysis, follow-up duration adjustment to event episodes was performed to account for death less than a year.

RESULTSForty-four patients (mean age 79 years, 39% men) were followed up for 15±8 months. Fifty-seven percent had diabetes, 80% ischaemic heart disease, and 60% chronic kidney disease. All reported functional class III/IV at enrolment. Mean serum sodium was 136±6 mmol/L, and creatinine 186±126 mmol/L. Thirty (68%) died within the programme. Mean time to death was 5.5 months. Mean all-cause and HF hospitalisations were 3.6 and 2.0 per patient before enrolment, but improved to 1.0 and 0.6 respectively after ACP. Thirty-six (71%) patients had fewer HF hospitalisations. When only those who survived more than a year were considered (n = 14), 10 (71%) and 9 (64%) experienced reduced HF (mean: 1.4 episodes per patient) and all-cause hospitalisations (mean: 2.2 episodes per patient) respectively.

CONCLUSIONHome-based advance care programme is potentially effective in reducing healthcare utilisation of end-stage HF patients, primarily by reducing HF rehospitalisations, and in probably saving costs as well.

Aged ; Aged, 80 and over ; Diabetes Mellitus ; Female ; Health Care Costs ; Health Services ; economics ; utilization ; Heart Failure ; complications ; economics ; therapy ; Home Care Services, Hospital-Based ; economics ; Hospitalization ; economics ; statistics & numerical data ; Humans ; Male ; Myocardial Ischemia ; complications ; Palliative Care ; economics ; methods ; Prospective Studies ; Registries ; Renal Insufficiency, Chronic ; complications ; Tertiary Care Centers