Are We Overradiating Patients with Irritable Bowel Syndrome?

<b><i>Introduction:</i></b> Protracted exposures to small doses of radiation, even cumulative effective doses (CED) as low as 50–100 mSv, may increase the risk for malignancy. Medical radiation exposure has not been rigorously examined for patients with irritable bowel syndrome (IBS). We examined medical radiation exposure in patients with IBS at a tertiary care center in the USA. <b><i>Methods:</i></b> Patients diagnosed with IBS at our institute from 2009 to 2018 were included in a retrospective cohort study. Medical charts were examined to calculate total and annual CED. <b><i>Results:</i></b> 221 patients were included; mean CED was 40.32 mSv (SD: 54.36). Fifty-nine participants (26.7%) received &#x3e;50 mSv of CED with 27 participants (12.2%) exceeding 100 mSv. Conventional imaging, nuclear medicine, and fluoroscopy accounted for 74.08, 12.93, and 12.98% of total CED, respectively. CT scans contributed to 66.61% of total CED. Outpatient orders accounted for 37.96% of total CED, while 31.4% of total CED was ordered in the emergency department. Population-specific high total CED was calculated as 105.65 mSv. Multivariable binomial logistic regression model found that comorbid anxiety, chronic pain medication use, and diarrhea-predominant IBS were independently positively associated with population-specific high CED exposure. No significant temporal trend in peri-diagnostic mean CED was found. <b><i>Conclusion:</i></b> Patients with IBS receive high amounts of medical radiation, with 1 in 4 patients reaching at-risk levels of 50 mSv or more. Usage of pain medication at home, comorbid anxiety, and IBS-D are independently linked to an increased risk of high CED.

What’s New for Clinical Whole-body MRI (WB-MRI) in the 21st Century

Whole-body MRI (WB-MRI) has evolved since its first introduction in the 1970s as an imaging technique to detect and survey disease across multiple sites and organ systems in the body. The development of diffusion-weighted MRI (DWI) has added a new dimension to the implementation of WB-MRI on modern scanners, offering excellent lesion-to-background contrast, while achieving acceptable spatial resolution to detect focal lesions 5 to 10 mm in size. MRI hardware and software advances have reduced acquisition times, with studies taking 40–50 min to complete. The rising awareness of medical radiation exposure coupled with the advantages of MRI has resulted in increased utilization of WB-MRI in oncology, paediatrics, rheumatological and musculoskeletal conditions and more recently in population screening. There is recognition that WB-MRI can be used to track disease evolution and monitor response heterogeneity in patients with cancer. There are also opportunities to combine WB-MRI with molecular imaging on PET-MRI systems to harness the strengths of hybrid imaging. The advent of artificial intelligence and machine learning will shorten image acquisition times and image analyses, making the technique more competitive against other imaging technologies.

Other useful facts

This chapter assembles a variety of useful facts and concepts of use in everyday oral and maxillofacial surgery. This includes the composition of products such as Carnoy’s solution, Whitehead’s varnish, and tumescent solution; the uses of botulinum toxin in oral and maxillofacial surgery; key terms used in statistics which are of use in the interpretation of published data; important facts surrounding the anatomy of the infratemporal fossa; levels of critical care commonly encountered in the UK; medical radiation exposure regulations and guidance; wound care evaluation and management; revalidation; and less commonplace aspects of oral and maxillofacial surgery, such as facial transplantation.