Towards 24/7 MRI: the effect of routine weekend inpatient MRI scanning on patient waiting times.

BACKGROUND: Demand for inpatient MRI outstrips capacity which results in long waiting lists. The hospital commenced a routine weekend MRI service in January 2023. AIM: The aim of this study was to investigate the effect of a limited routine weekend MRI service on MRI turnaround times. METHODS: Waiting times for inpatient MRI scans performed before and after the introduction of weekend MRI from January 1 to August 31, 2022, and January 1 to August 31, 2023, were obtained. The turnaround time (TAT) and request category for each study were calculated. Category 1 requests were required immediately, category 2 requests were urgent and category 3 requests were routine. RESULTS: There was a 6% (n = 128) increase in MRI inpatient scanning activity in 2023 (n = 2449) compared to 2022 (n = 2322). There was a significant improvement in overall mean TAT for inpatient MRIs (p < .001) in 2023 (mean 65.2 h, range 0-555 h) compared to 2022 (mean 98.3 h, range 0-816 h). There was no significant difference in the mean waiting time for category 1 MRIs between 2022 and 2023. There was a significant improvement (p < .001) in mean waiting time in 2023 (mean 37.2 h, range 0-555) compared to 2022 (mean 55.4 h, range 0-816) for category 2 MRI. The mean waiting time for category 3 studies also significantly improved (p < .001) in 2023 (mean 93.4 h, range 1-2663) when compared to 2022 (mean 154.8, range 1-1706). CONCLUSION: Routine weekend inpatient MRI significantly shortens inpatient waiting times.

The Rolling Stones: A case report of two surgical abdomens linked by migrating gallstones.

INTRODUCTION: Acute abdominal pain accounts for 5% of all presentations to the emergency department (Stoker et al., 2009). Two of the most common causes are acute appendicitis and acute cholecystitis (Ferris et al., 2017). PRESENTATION: A 70-year-old man presented with acute calculous cholecystitis. He subsequently deteriorated clinically and re-imaging revealed interval migration of stones from the biliary system to the appendix with resultant acute appendicitis. DISCUSSION: Although both acute appendicitis and acute cholecystitis are common, dual pathology is rare. There are a small number of case reports of gallstones causing appendicitis (Vicari, 1964; Siegal et al., 1990; Meade, 1960). CONCLUSION: Our case report nicely illustrates. a) The importance of considering dual pathology, especially when there is an unexpected change in the patient's clinical status. b) The CT features of two common acute surgical pathologies. c) The value of cholecystostomy- performed in the Interventional Radiology suite- as a temporizing measure to allow the patient to recover from a critical illness.

A twisted tale-radiological imaging features of COVID-19 on 18F-FDG PET/CT.

The COVID-19 pandemic has had a major impact on health care systems across the globe in a short period of time. There is a growing body of evidence surrounding the findings on hybrid imaging with FDG-PET/CT, and this case highlights the importance of molecular imaging in better understanding of the biomarkers of the disease which ultimately determine the success in building a model to predict the disease severity and monitoring the response to treatment.

Characterizing caspase-1 involvement during esophageal disease progression.

Barrett's esophagus (BE) is an inflammatory condition and a neoplastic precursor to esophageal adenocarcinoma (EAC). Inflammasome signaling, which contributes to acute and chronic inflammation, results in caspase-1 activation leading to the secretion of IL-1ß and IL-18, and inflammatory cell death (pyroptosis). This study aimed to characterize caspase-1 expression, and its functional importance, during disease progression to BE and EAC. Three models of disease progression (Normal-BE-EAC) were employed to profile caspase-1 expression: (1) a human esophageal cell line model; (2) a murine model of BE; and (3) resected tissue from BE-associated EAC patients. BE patient biopsies and murine BE organoids were cultured ex vivo in the presence of a caspase-1 inhibitor, to determine the importance of caspase-1 for inflammatory cytokine and chemokine secretion.Epithelial caspase-1 expression levels were significantly enhanced in BE (p < 0.01). In contrast, stromal caspase-1 levels correlated with histological inflammation scores during disease progression (p < 0.05). Elevated secretion of IL-1ß from BE explanted tissue, compared to adjacent normal tissue (p < 0.01), confirmed enhanced activity of caspase-1 in BE tissue. Caspase-1 inhibition in LPS-stimulated murine BE organoids caused a significant reduction in IL-1ß (p < 0.01) and CXCL1 (p < 0.05) secretion, confirming the importance of caspase-1 in the production of cytokines and chemokines associated with disease progression from BE to EAC. Targeting caspase-1 activity in BE patients should therefore be tested as a novel strategy to prevent inflammatory complications associated with disease progression.

Targeting hallmarks of cancer to enhance radiosensitivity in gastrointestinal cancers.

Radiotherapy is used in the treatment of approximately 50% of all malignancies including gastrointestinal cancers. Radiation can be given prior to surgery (neoadjuvant radiotherapy) to shrink the tumour or after surgery to kill any remaining cancer cells. Radiotherapy aims to maximize damage to cancer cells, while minimizing damage to healthy cells. However, only 10-30% of patients with rectal cancer or oesophageal cancer have a pathological complete response to neoadjuvant chemoradiation therapy, with the rest suffering the negative consequences of toxicities and delays to surgery with no clinical benefit. Furthermore, in pancreatic cancer, neoadjuvant chemoradiation therapy results in a pathological complete response in only 4% of patients and a partial pathological response in only 31%. Resistance to radiation therapy is polymodal and associated with a number of biological alterations both within the tumour itself and in the surrounding microenvironment including the following: altered cell cycle; repopulation by cancer stem cells; hypoxia; altered management of oxidative stress; evasion of apoptosis; altered DNA damage response and enhanced DNA repair; inflammation; and altered mitochondrial function and cellular energetics. Radiosensitizers are needed to improve treatment response to radiation, which will directly influence patient outcomes in gastrointestinal cancers. This article reviews the literature to identify strategies - including DNA-targeting agents, antimetabolic agents, antiangiogenics and novel immunotherapies - being used to enhance radiosensitivity in gastrointestinal cancers according to the hallmarks of cancer. Evidence from radiosensitizers from in vitro and in vivo models is documented and the action of radiosensitizers through clinical trial data is assessed.

Can the Efficacy of [18F]FDG-PET/CT in Clinical Oncology Be Enhanced by Screening Biomolecular Profiles?

Positron Emission Tomography (PET) is a functional imaging modality widely used in clinical oncology. Over the years the sensitivity and specificity of PET has improved with the advent of specific radiotracers, increased technical accuracy of PET scanners and incremental experience of Radiologists. However, significant limitations exist-most notably false positives and false negatives. Additionally, the accuracy of PET varies between cancer types and in some cancers, is no longer considered a standard imaging modality. This review considers the relative influence of macroscopic tumour features such as size and morphology on 2-Deoxy-2-[18F]fluoroglucose ([18F]FDG) uptake by tumours which, though well described in the literature, lacks a comprehensive assessment of biomolecular features which may influence [18F]FDG uptake. The review aims to discuss the potential influence of individual molecular markers of glucose transport, glycolysis, hypoxia and angiogenesis in addition to the relationships between these key cellular processes and their influence on [18F]FDG uptake. Finally, the potential role for biomolecular profiling of individual tumours to predict positivity on PET imaging is discussed to enhance accuracy and clinical utility.