Aim: Cardiac phase-correlated (4D) imaging is employed in small animal models of cardiovascular diseases (CVD). When 4D-PET and 4D-Ct are combined together, a comprehensive view of the cardiac function and morphology is obtained, allowing a motion artifact-free quantification of PET tracer regional distribution in the myocardium along with LV regional kinetics. This work presents the results of 4D-PET/CT imaging of small animals obtained with the IRIS PET/CT scanner (Inviscan,France). Materials and methods: The PET component of the IRIS scan-ner consists of 16 modular detectors arranged in two octagonal rings. ThePET field-of-view is 95mm axial × 80mm diameter. PET images are reconstructed with 3D-OSEM. The CT section is equipped with a X-ray source with tungsten anode (35-80kV, 80W) and a flat-panel CMOS-based detector. The FOV diameter of the CT is 90mm, and the maximum FOV length is 110mm. CT images are reconstructed using a Feldkamp algorithm. The PET ring and the CT components are placed on the same rotating gantry having a total rotation range of [ +190°; -190°]. The offset between the centers of the PET and CT fields of view (FOV) is 120mm. For PET imaging ECG gating is used to extract the individual cardiac phases. The gating signal from the physiological monitoring system (SA instrument Inc. Model 1030) was fed into the PET acquisition system. For each cycle, 8 equally spaced frames are produced and then retrospectively rearranged to generate list-mode files corresponding to an equal number of phases. Respiratory gating is also applied, excluding from the list-mode file all events recorded in the end-inspiration phase. For CT, the gated scanning protocol consisted in a multi-arc rotating acquisition with1000-20000 projections over the entire rotation (360°), with a total scan times from 2 to 6 minutes. The absorbed dose was 200-400 mGy. The physiological signals are derived analyzing the projection data, and the cardiac cycle was partitioned in 8-40 frames. Each projection was assigned to one or more cardiac phases with proper weights, excluding all projections in the end-inspiration respiratory phase. Results and Conclusions: Phase-correlated cardiac images have been obtained on mice and rats with the IRIS scanner for both PET and CT modality. Multimodal 4D-PET/CT cardiac images are presented, along with example of quantification of cardiac morphofunctional parameters.
Multimodal 4D cardiac imaging with the preclinical IRIS PET/CT scanner
BELCARI, NICOLA;CAMARLINGHI, NICCOLO';SPORTELLI, GIANCARLO;DEL GUERRA, ALBERTO
2016-01-01
Abstract
Aim: Cardiac phase-correlated (4D) imaging is employed in small animal models of cardiovascular diseases (CVD). When 4D-PET and 4D-Ct are combined together, a comprehensive view of the cardiac function and morphology is obtained, allowing a motion artifact-free quantification of PET tracer regional distribution in the myocardium along with LV regional kinetics. This work presents the results of 4D-PET/CT imaging of small animals obtained with the IRIS PET/CT scanner (Inviscan,France). Materials and methods: The PET component of the IRIS scan-ner consists of 16 modular detectors arranged in two octagonal rings. ThePET field-of-view is 95mm axial × 80mm diameter. PET images are reconstructed with 3D-OSEM. The CT section is equipped with a X-ray source with tungsten anode (35-80kV, 80W) and a flat-panel CMOS-based detector. The FOV diameter of the CT is 90mm, and the maximum FOV length is 110mm. CT images are reconstructed using a Feldkamp algorithm. The PET ring and the CT components are placed on the same rotating gantry having a total rotation range of [ +190°; -190°]. The offset between the centers of the PET and CT fields of view (FOV) is 120mm. For PET imaging ECG gating is used to extract the individual cardiac phases. The gating signal from the physiological monitoring system (SA instrument Inc. Model 1030) was fed into the PET acquisition system. For each cycle, 8 equally spaced frames are produced and then retrospectively rearranged to generate list-mode files corresponding to an equal number of phases. Respiratory gating is also applied, excluding from the list-mode file all events recorded in the end-inspiration phase. For CT, the gated scanning protocol consisted in a multi-arc rotating acquisition with1000-20000 projections over the entire rotation (360°), with a total scan times from 2 to 6 minutes. The absorbed dose was 200-400 mGy. The physiological signals are derived analyzing the projection data, and the cardiac cycle was partitioned in 8-40 frames. Each projection was assigned to one or more cardiac phases with proper weights, excluding all projections in the end-inspiration respiratory phase. Results and Conclusions: Phase-correlated cardiac images have been obtained on mice and rats with the IRIS scanner for both PET and CT modality. Multimodal 4D-PET/CT cardiac images are presented, along with example of quantification of cardiac morphofunctional parameters.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
