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Purpose: To determine the feasibility of replacing the mid treatment cone beam computed tomography (MT CBCT) image with Intrafraction Imaging (IFI) acquired concurrently during dose delivery in lung Stereotactic Ablative Body Radiation therapy (SABR) patients, and thus improve treatment efficiency. Methods and Materials: A review of departmental imaging data was performed on ten lung SABR patients treated with dual arc volumetric modulated arc therapy (VMAT) on an Elekta Versa HD linear accelerator with XVI imaging software.IFI data was extracted and a database of the translational (TX, TY, TZ) and the rotational (RX, RY, RZ) position errors was created for retrospective comparison, with the values of the MT CBCT for the same patients, treated between March 2021 and March 2022 at our center. The data was evaluated for correlation between the values in all 6° of freedom. Results: The inter-class correlation (ICC) coefficient for Tx was 0.89 (95% CI, 0.80-0.94), Ty was 0.69 (95% CI, 0.49-0.82), Tz was 0.89 (95% CI, 0.82-0.95) in the translational planes, and Rx was 0.79 (95% CI, 0.65-0.88), Ry was 0.79 (95% CI, 0.65-0.88), and Rz was 0.91 (95% CI, 0.84-0.95) in rotational planes.The Bland-Altman (BA) statistics for Tx had a bias of –1.22 × 10−3, with an upper limit of agreement (UOA) of 0.07, and a lower limit of agreement (LOA) of –0.07, for Ty the bias was 0.01 (UOA: 0.18; LOA: –0.16), Tz bias was 2.6 × 10−3(UOA: 0.10; LOA: –0.09), Rx bias was 0.09 (UOA: 0.82; LOA: –0.64), Ry bias was –0.04 (UOA: 1.08; LOA: –1.16) and Rz was –0.03 (UOA: 0.44; LOA: –0.51). Conclusions: The ICC was excellent for Tx, Tz, Rx, y, z, and good for Ty. The data demonstrated promising correlation between IFI and MT CBCT values, and therefore supports the use of IFI for clinical decision making and improving treatment efficiency.

There is a clear and urgent call to transform our food systems as a critical nexus to tackle ongoing global climate, biodiversity, equity, and nutrition crises. Many food and agricultural innovations are being developed and scaled but these innovations often target sector-specific problems and remain disconnected from the more complex demand for transformative change at scale. To bridge this demand for systemic change within the innovation ecosystem, initiatives are applying various approaches such as visioning, holistic assessments, innovation portfolio management and multistakeholder co-creation. Here we report on insights from applying a food systems tailored backcasting approach in a diversity of settings since 2021, including a national food system dialogue, a youth business innovation challenge, a landscape multi-stakeholder platform, a public-private sector co-learning session, an agroecological transitions program, and a hybrid food systems university course for graduate students and global professionals. We thereby build on existing literature and case studies of how change happens (or does not happen) and aim to use those insights to support food systems change makers. Across these settings, the backcasting approach asks participants to connect innovations with broader systems-change visions, to anticipate tradeoffs for multiple food system outcomes and population groups, and to cross sectoral boundaries. The use cases demonstrate that the backcasting process contributes to changes in views, practices and structures that participants work with. Specifically, it supports moving beyond “silver bullet” innovation approaches, the bundling of social and technical innovations, and building action-oriented cross-sectoral bridges. Food systems change is complex and innovations alone are insufficient to address its complexity. But innovations can play a positive role if connected to more holistic systems-change processes and goals. Considering strengths and limitations of the backcasting approach, the diversity of practical applications supports its potential to connect innovations to holistic food systems visions, to strengthen cross-sectoral collaboration and to bundle social and technical innovations for desirable food systems change.