Treatment planning for MR-guided SBRT of pancreatic tumors on a 1.5 T MR-Linac: A global consensus protocol

Background and purpose: Treatment planning for MR-guided stereotactic body radiotherapy (SBRT) for pancreatic tumors can be challenging, leading to a wide variation of protocols and practices. This study aimed to harmonize treatment planning by developing a consensus planning protocol for MR-guided pancreas SBRT on a 1.5 T MR-Linac. Materials and methods: A consortium was founded of thirteen centers that treat pancreatic tumors on a 1.5 T MR-Linac. A phased planning exercise was conducted in which centers iteratively created treatment plans for two cases of pancreatic cancer. Each phase was followed by a meeting where the instructions for the next phase were determined. After three phases, a consensus protocol was reached. Results: In the benchmarking phase (phase I), substantial variation between the SBRT protocols became apparent (for example, the gross tumor volume (GTV) D99% ranged between 36.8 – 53.7 Gy for case 1, 22.6 – 35.5 Gy for case 2). The next phase involved planning according to the same basic dosimetric objectives, constraints, and planning margins (phase II), which led to a large degree of harmonization (GTV D99% range: 47.9–53.6 Gy for case 1, 33.9–36.6 Gy for case 2). In phase III, the final consensus protocol was formulated in a treatment planning system template and again used for treatment planning. This not only resulted in further dosimetric harmonization (GTV D99% range: 48.2–50.9 Gy for case 1, 33.5–36.0 Gy for case 2) but also in less variation of estimated treatment delivery times. Conclusion: A global consensus protocol has been developed for treatment planning for MR-guided pancreatic SBRT on a 1.5 T MR-Linac. Aside from harmonizing the large variation in the current clinical practice, this protocol can provide a starting point for centers that are planning to treat pancreatic tumors on MR-Linac systems

Evaluation of a mobile screening service for abdominal aortic aneurysm in Broken Hill, a remote regional centre in far western NSW

Objectives: To evaluate the feasibility of a mobile screening service model for abdominal aortic aneurysm (AAA) in a remote population centre in Australia. Design: Screening test evaluation. Setting: A remote regional centre (population: 20 000) in far western NSW. Participants: Men aged 65-74 years, identified from the Australian Electoral roll. Interventions: A mobile screening service using directed ultrasonography, a basic health check and post-screening consultation. Main outcome measures: Attendance at the screening program, occurrence of AAA in the target population and effectiveness of screening processes. Results: A total of 516 men without a previous diagnosis of AAA were screened, an estimated response rate of 60%. Of these, 463 (89.7%) had a normal aortic diameter, 28 (5.4%) ectatic and 25 (4.9%) a small, moderate or significant aneurysm. Two men with AAA were recommended for surgery. Feedback from participants indicated that the use of a personalised letter of invitation helped with recruitment, that the screening process was acceptable and the service valued. Conclusions: It is feasible to organise and operate a mobile AAA screening service from moderate sized rural and remote population centres. This model could be scaled up to provide national coverage for rural and remote residents. © 2010 The Authors. Journal compilatio

A pilot randomised controlled parallel arm trial evaluating treatment satisfaction with the Omnipod DASH® Insulin Management System compared with usual care in adults with type 1 diabetes in Australia: rationale, study design and methodologies

Abstract Background Insulin pump therapy (IPT) improves glucose control in people with type 1 diabetes (T1D) compared with multiple daily injections (MDI). However, their size, the tethered insulin infusion set, intrusiveness when operating the device and the need to disconnect during showering limit their acceptance to many who may benefit. The Omnipod DASH® Insulin Management System is a small waterproof tubeless device which is wirelessly controlled by a handheld device which may be an acceptable alternative. However, there are no randomised controlled trials focusing on the impact on user perceptions of tubeless insulin pump therapy. This pilot study aims to assess study feasibility and acceptability of patch pump therapy compared with usual care in adults with T1D in Australia to inform power calculations and progression to a large-scale multi-site randomised controlled study. Methods A pilot multi-site parallel randomised controlled study will be conducted in sixty-four adults with T1D who are managed on MDI or IPT and self-monitoring with finger-stick blood glucose from four specialist diabetes centres in Victoria, Australia. Following carbohydrate counting education, participants will be randomised to use Omnipod DASH® System (Omnipod group) or continue usual care (usual care group) for 12 weeks, followed by a 12-week extension phase where all participants will use Omnipod DASH® System. The primary outcome measure is feasibility determined by study completion rates with a threshold of 0.80. Acceptability of the intervention (Omnipod DASH® System) will be assessed by the difference in Diabetes Technology Questionnaire ‘current’ (DTQ-current) score at 12 weeks post-randomisation compared to baseline. Secondary outcomes will include other measures of user acceptance, process outcomes, resource outcomes, participant-centred outcomes, healthcare professional perceptions and glycaemic outcomes. Discussion This pilot study will provide insights regarding the feasibility of the study design and the first data regarding user acceptance of insulin patch pump technology in Australian T1D adults. We anticipate that this study will provide information informing the design of a larger study evaluating the impact of patch pumps on subjective outcomes that are of significance to the person living with T1D. Trial registration Australian New Zealand Clinical Trials Registry ( https://anzctr.org.au/ ) ACTRN12621001195842 (8th September 2021). Please refer to Additional file 1: Appendix 1 for full details

Fast track to health - Intermittent energy restriction in adolescents with obesity. A randomised controlled trial study protocol

Background: Intermittent energy restriction (IER) has shown early success in adolescents with obesity, however efficacy trials are needed. This study aims to determine if IER results in lower body mass index (BMI) z-score after 52 weeks in metabolically unhealthy adolescents with obesity compared with continuous energy restriction (CER).Methods/design: This is a prospective, randomised, multi-centre trial conducted in tertiary care settings, with three phases: jumpstart (weeks 0-4); intensive intervention (weeks 5-16); continued intervention and/or maintenance (weeks 17-52). During the jumpstart phase, all participants follow a very low energy diet (similar to 800 kcal/3350 kJ/day), then transition to their allocated intervention: IER or CER. IER involves three energy-restricted days/week, consuming one-third of daily energy requirements (similar to 600-700 kcal/2500-2950 kJ/day), and four days/week of a healthy meal plan. The CER, which is current standard care, has individually tailored energy prescription based on age and sex (13-14 years, 1430-1670 kcal/6000-7000 kJ/day; 15-17 years, 1670-1900 kcal/7000-8000 kJ/day). The study will recruit 186 (93 per arm) treatment-seeking adolescents aged 13-17 years with obesity and at least one metabolic co-morbidity. The primary outcome is change in BMI z-score at 52 weeks. Secondary outcomes are changes at 4, 16 and 52 weeks in: body composition; diet quality, food choices and food patterns; cardio-metabolic risk factors; physical activity and sedentary behaviour; sleep and psycho-behavioural measures.Discussion: This study challenges existing clinical paradigms that CER is the only method for weight management in metabolically unhealthy adolescents. If successful, IER may offer an alternate medical nutrition therapy approach for those seeking treatment in tertiary settings. (C) 2019 Published by Elsevier Ltd on behalf of Asia Oceania Association for the Study of Obesity

Predicting Alzheimer disease with β-amyloid imaging : results from the Australian imaging, biomarkers, and lifestyle study of ageing

Objective Biomarkers for Alzheimer disease (AD) can detect the disease pathology in asymptomatic subjects and individuals with mild cognitive impairment (MCI), but their cognitive prognosis remains uncertain. We aimed to determine the prognostic value of β-amyloid imaging, alone and in combination with memory performance, hippocampal atrophy, and apolipoprotein E ε4 status in nondemented, older individuals. Methods A total of 183 healthy individuals (age = 72.0 ± 7.26 years) and 87 participants with MCI (age = 73.7 ± 8.27) in the Australian Imaging, Biomarkers, and Lifestyle study of ageing were studied. Clinical reclassification was performed after 3 years, blind to biomarker findings. β-Amyloid imaging was considered positive if the 11C-Pittsburgh compound B cortical to reference ratio was ≥1.5. Results Thirteen percent of healthy persons progressed (15 to MCI, 8 to dementia), and 59% of the MCI cohort progressed to probable AD. Multivariate analysis showed β-amyloid imaging as the single variable most strongly associated with progression. Of combinations, subtle memory impairment (Z score = -0.5 to -1.5) with a positive amyloid scan was most strongly associated with progression in healthy individuals (odds ratio [OR] = 16, 95% confidence interval [CI] = 3.7-68; positive predictive value [PPV] = 50%, 95% CI = 19-81; negative predictive value [NPV] = 94%, 95% CI = 88-98). Almost all amnestic MCI subjects (Z score ≤ -1.5) with a positive amyloid scan developed AD (OR = ∞; PPV = 86%, 95% CI = 72-95; NPV = 100%, 95% CI = 80-100). Hippocampal atrophy and ε4 status did not add further predictive value. Interpretation Subtle memory impairment with a positive β-amyloid scan identifies healthy individuals at high risk for MCI or AD. Clearly amnestic patients with a positive amyloid scan have prodromal AD and a poor prognosis for dementia within 3 years.9 page(s

[In Press] Estimating flying-fox mortality associated with abandonments of pups and extreme heat events during the austral summer of 2019-20

Abstract. Mass mortalities in flying-foxes occur in summers that reach extremely hot temperatures. In this study, we examine the spatiotemporal distributions of mortality from pup abandonments and extreme heat events in Australian flying-fox camps during the 2019–20 summer. We recorded data on flying-fox mortality in known affected camps and applied a standard method to estimate the number of deaths. Pup mortalities from abandonments were recorded in 10 camps in New South Wales. A minimum estimate of 2612 flying-foxes died in pup abandonments, the majority of which occurred in one camp in Bomaderry. Die-offs from extreme heat events were recorded in 40 camps associated with eight separate heat events in south-eastern Australia. A minimum estimate of 72 175 flying-foxes died during these heat events, which all occurred within the range of the threatened grey-headed flying-fox (Pteropus poliocephalus). Further, 409 and 2251 live flying-foxes were taken into care from pup abandonments and heat events respectively. The minimum mortality estimated represents the highest recorded mortality of Australian flying-foxes within a single summer. This highlights a need to restore vegetation in flying-fox foraging areas and camps, address anthropogenic climate change and gather more empirical data to inform heat stress interventions to minimise flying-fox mortalities