Radiology advocacy: Promoting collaboration between trainees and professional societies.

From mammographic screening guidelines to resident work hour regulations, public policy affects every aspect of the practice of radiology and ultimately determines how radiological care is delivered to patients. Shaping public policy through advocacy is therefore critical to ensure patient access to equitable, high-quality radiological care. In advocacy, individual practicing radiologists and radiology trainees can increase the scope of their influence by collaborating with professional radiology societies. When radiology trainees participate in organized radiology advocacy, they learn about regulatory and legislative issues that will affect their careers, and they learn how to effect policy change. Radiology societies in turn benefit from trainee involvement, as engaging trainees early in their careers leads to more robust future participation and leadership. To encourage trainee involvement, radiology societies can engage individual residency programs and medical student radiology interest groups, invest in trainee-focused events, and maximize the number of positions of responsibility open to trainees. To circumvent the barriers to participation that many trainees face, radiology societies can make meeting proceedings free and available through virtual mediums. Through active collaboration, trainees and professional societies can help assure a bright future for radiologists and patients in need of radiological care.

Inter- and intrafraction motion assessment and accumulated dose quantification of upper gastrointestinal organs during magnetic resonance-guided ablative radiation therapy of pancreas patients.

BACKGROUND AND PURPOSE: Stereotactic body radiation therapy (SBRT) of locally advanced pancreatic cancer (LAPC) is challenging due to significant motion of gastrointestinal (GI) organs. The goal of our study was to quantify inter and intrafraction deformations and dose accumulation of upper GI organs in LAPC patients. MATERIALS AND METHODS: Five LAPC patients undergoing five-fraction magnetic resonance-guided radiation therapy (MRgRT) using abdominal compression and daily online plan adaptation to 50 Gy were analyzed. A pre-treatment, verification, and post-treatment MR imaging (MRI) for each of the five fractions (75 total) were used to calculate intra and interfraction motion. The MRIs were registered using Large Deformation Diffeomorphic Metric Mapping (LDDMM) deformable image registration (DIR) method and total dose delivered to stomach_duodenum, small bowel (SB) and large bowel (LB) were accumulated. Deformations were quantified using gradient magnitude and Jacobian integral of the Deformation Vector Fields (DVF). Registration DVFs were geometrically assessed using Dice and 95th percentile Hausdorff distance (HD95) between the deformed and physician's contours. Accumulated doses were then calculated from the DVFs. RESULTS: Median Dice and HD95 were: Stomach_duodenum (0.9, 1.0 mm), SB (0.9, 3.6 mm), and LB (0.9, 2.0 mm). Median (max) interfraction deformation for stomach_duodenum, SB and LB was 6.4 (25.8) mm, 7.9 (40.5) mm and 7.6 (35.9) mm. Median intrafraction deformation was 5.5 (22.6) mm, 8.2 (37.8) mm and 7.2 (26.5) mm. Accumulated doses for two patients exceeded institutional constraints for stomach_duodenum, one of whom experienced Grade1 acute and late abdominal toxicity. CONCLUSION: LDDMM method indicates feasibility to measure large GI motion and accumulate dose. Further validation on larger cohort will allow quantitative dose accumulation to more reliably optimize online MRgRT.