PURPOSE: To monitor the evolution of radiation-induced @entity299 in a @entity235 model using hybrid positron emission tomography (PET/magnetic resonance imaging (MRI). METHODS: Research ethics approval was obtained for a longitudinal imaging study of 5 @entity235 after cardiac irradiation. Animals were imaged at baseline, 3 months, 6 months, and 12 months post cardiac irradiation using a hybrid PET-MRI system (Biograph @entity28651 , Siemens Healthcare). The imaging protocol was designed to assess changes in @entity299 using @entity419 ( @entity419 ) PET tracer. In order to image @entity299 , the normal myocardial uptake of @entity413 was suppressed prior to the injection of @entity419 . The suppression of glycolysis was achieved through; fasting (16-21 hours prior to the start of imaging) and an intravenous injection of heparin immediately followed by a 20% lipid infusion 20 min prior to the injection of @entity419 . The standard uptake value (SUV) obtained from 17 myocardial regions were used to compare FDG scans. All animals received a simulation CT scan (GE Medical Systems) for radiation treatment planning. Radiation treatment plans were created using the Pinncale3 treatment planning system (Philips Radiation Oncology Systems) and designed to resemble the typical cardiac exposure during left-sided @entity0 radiotherapy. Cardiac irradiations were performed in a single fraction using a TrueBeam linear accelerator (Varian Medical Systems). RESULTS: The delivered dose (mean    standard error) to heart, left ventricle, and left anterior descending artery were 1.7  0.1 Gy, 2.7  0.1 Gy, and 5.5  0.3 Gy respectively. At these doses, a significant increase in @entity419 uptake within the entire heart relative to baseline (1.1  0.02 g/ml) uptake was observed. @entity419 uptake at 3 months, 6 months, and 12 months post irradiation were 1.8  0.03 g/ml, 2.4  0.06 g/ml, and 2.6  0.11 g/ml respectively. CONCLUSION: Low doses of limited cardiac irradiation show evidence of a persistent global inflammatory response that can be detected using @entity419 PET imaging. This work was supported through the Translational @entity0 Studentship award, funded in part by the @entity0 Society of Canada. Additional financial support is provided by the London Regional Cancer Program Catalyst Grant and the Thames Valley Veterinary Services.

WE-FG-202-06: The Use of Hybrid PET MRI for Identifying the Presence of XXXX Following External Beam Irradiation.

@entity28651 :: ('50771(Tax:10090)', 'Gene') :: ['mMR'] @entity419 :: ('MESH:D019788', 'Chemical') :: ['(18) F-fluorodeoxyglucose', '(18) F-FDG'] @entity0 :: ('MESH:D001943', 'Disease') :: ['Breast Cancer', 'breast cancer'] @entity235 :: ('9615', 'Species') :: ['canine', 'canines'] @entity299 :: ('MESH:D006331', 'Disease') :: ['cardiac inflammation'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose']
@entity299 :: (MESH:D006331,Disease) :: ['Cardiac Inflammation']
