Background: We investigated the impact of varying contrast medium (CM) densities and x-ray tube potentials on contrast enhancement (CE), image quality and radiation dose in thoracic computed tomography (CT) using two different scanning techniques. Methods: Seven plastic tubes containing seven different CM densities ranging from of 0 to 600 HU were positioned inside a commercial chest phantom with padding, representing three different patient sizes. Helical scans of the phantom in single-source mode were obtained with varying tube potentials from 70 to 140 kVp. A constant volume CT dose index (CTDIvol) depending on phantom size and automatic dose modulation was tested. CE (HU) and image quality (contrast-to-noise ratio, CNR) were measured for all combinations of CM density and tube potential. A reference threshold of CE and kVp was defined as ≥ 200 HU and 120 kVp. Results: For the medium-sized phantom, with a specific CE of 100–600 HU, the diagnostic CE (200 HU) at 70 kVp was ~ 90% higher than at 120 kVp, for both scan techniques (p < 0.001). Changes in CM density/specific HU together with lower kVp resulted in significantly higher CE and CNR (p < 0.001). When changing only the kVp, no statistically significant differences were observed in CE or CNR (p ≥ 0.094), using both dose modulation and constant CTDIvol. Conclusions: For thoracic CT, diagnostic CE (≥ 200 HU) and maintained CNR were achieved by using lower CM density in combination with lower tube potential (< 120 kVp), independently of phantom size.

Background: Artifacts caused by metal implants are challenging when undertaking computed tomography (CT). Dedicated algorithms have shown promising results although with limitations. Tin filtration (Sn) in combination with high tube voltage also shows promise but with limitations. There is a need to examine these limitations in more detail. The purpose of this study was to investigate the impact of different metal artefact reduction (MAR) algorithms, tin filtration, and ultra-high-resolution (UHR) scanning, alone or in different combinations in both phantom and clinical settings. Methods: An ethically approved clinical and phantom study was conducted. A modified Catphan® phantom with titanium and stainless-steel inserts was scanned with six different MAR protocols with tube voltage ranging from 80 to 150 kVp. Other scan parameters were kept identical. The differences (∆) in mean HU and standard deviation (SD) in images, with and without metal, were measured and compared. In the clinical study, three independent readers performed visual image quality assessments on eight different protocols using retrospectively acquired images. Results: Iterative MAR had the lowest ∆HU and ∆SD in the phantom study. For images of the forearm, the soft tissue noise for Sn-based 150-kVp UHR protocol with was significantly higher (p = 0.037) than for single-energy MAR protocols. All Sn-based 150-kVp protocols were rated significantly higher (p < 0.046 than the single-energy MAR protocols in the visual assessment. Conclusions: All Sn-based 150-kVp UHR protocols showed similar objective MAR in the phantom study, and higher objective MAR and significantly improved visual image quality than single-energy MAR. Relevance statement: Images with less metal artifacts and higher visual image quality may be more clinically optimal in CT examination of musculoskeletal patients with metal implants. Key points: • Metal artifact reduction algorithms and Sn filter combined with high kVp reduce artifacts. • Metal artifact reduction algorithms introduce new artifacts in certain metals. • Sn-based protocols alone may be considered as low metal artifact protocols. Graphical

Introduction: Several studies have demonstrated the psychological impact of the COVID‐19 pandemic on health care providers. However, there is little known about how the COVID‐19 pandemic has impacted radiation therapists (RTs) in Norway or Canada. The aim of this investigation was to study the psychological impact of working during the COVID‐19 pandemic among RTs in Canada and Norway.Methods: Online surveys were administered to a convenience sample of RTs and RT department managers. Approximately 2000 and 300 RTs were invited to participate from Canada and Norway, respectively. The RT survey collected information on demographics, work‐related stressors, psychological impact, quality of life, and workplace support programmes. The RT manager survey collected information on departmental changes, patient volumes, staff shortages and redeployment, personal protective equipment, and infection control measures. Descriptive analysis, group comparisons and logistic regression were used to examine the impact of COVID‐19 on RTs in the two countries, while open‐ended questions were examined through thematic analysis.Results: Work‐related stress and anxiety were prevalent among Canadian (n = 155) and Norwegian RTs (n = 124), with Canadian RTs reporting higher levels. Fear of transmission, changes in PPE usage, and changes in staffing were reported as the most frequent work‐related stressors. Themes related to working during the pandemic included: generalised anxiety; physical, emotional and cognitive symptoms of stress; and loneliness, as well as negative impact on health and quality of relationships. Survey findings from RT department managers in Canada (n = 12) and Norway (n = 13) suggest that the pandemic had an organisational impact on RT departments due to implemented infection control measures and changes in staffing.Conclusion: The COVID‐19 pandemic has led to similar stressors amongst Canadian and Norwegian RTs but relatively higher levels of psychological impact among Canadian RTs. Findings demonstrate the importance of mental health support programmes in the workplace to mitigate the psychological impact of the COVID‐19 pandemic on RTs.

Various national solutions have been considered and implemented to address the factors which limit radiographer engagement in conducting research. Nevertheless, national literature continues to suggest that radiographer engagement in research remains low. The aim of this study was to extend the existing evidence base by conducting an international survey to assess diagnostic radiographers and therapeutic radiographers involvement with, barriers to and support mechanisms for research. Data collection was obtained via an online questionnaire which was distributed by the International Society of Radiographers and Radiologic Technologists (ISRRT). The study population included an international sample of qualified diagnostic radiographers and therapeutic radiographers across clinical and academic contexts in a variety of different roles such as clinical practice, management, education and research. In total, 420 diagnostic radiographers and therapeutic radiographers completed the survey. Multiple reasons were identified that were considered to inhibit respondents from conducting research. 69.3% indicated a combination of reasons for lack of engagement with research, rather than one single issue. Examples of reasons include: lack of time, insufficient research funding, limited research expertise, and lack of a suitable mentorship scheme. A minor segment of survey respondents indicated involvement in research activity. Lack of dedicated time to research, mentors, and funding were among the main barriers to conduct research. Further research is required to explore what solutions are available to overcoming the barriers.