Feasibility of simultaneous PET/MR in diet-induced atherosclerotic minipig: a pilot study for translational imaging

TY - JOUR

T1 - Feasibility of simultaneous PET/MR in diet-induced atherosclerotic minipig

T2 - a pilot study for translational imaging

AU - Pedersen, Sune F

AU - Ludvigsen, Trine P

AU - Johannesen, Helle H

AU - Löfgren, Johan

AU - Ripa, Rasmus Sejersten

AU - Hansen, Adam E

AU - Ettrup, Anders J

AU - Christoffersen, Berit Ø

AU - Pedersen, Henrik D

AU - Olsen, Lisbeth H

AU - Højgaard, Liselotte

AU - Kjær, Andreas

PY - 2014

Y1 - 2014

N2 - Novel hybrid 18-fluoro-deoxy-D-glucose ((18)F-FDG) based positron emission tomography (PET) and magnetic resonance imaging (MRI) has shown promise for characterization of atherosclerotic plaques clinically. The purpose of this study was to evaluate the method in a pre-clinical model of diet-induced atherosclerosis, based on the Göttingen minipig. Using (18)F-FDG PET/MRI the goal was to develop and create a new imaging method in an in vivo animal model for translational studies of atherosclerosis. We used a strategy of multisequence MRI for optimal anatomical imaging of the abdominal aortas of the pigs (n=4): T1-weighted turbo spin-echo (T1-TSE), T2-weighted turbo spin-echo (T2-TSE) and proton density imaging with and without fat saturation. (18)F-FDG PET emission data were collected from a single bed position of the abdominal aorta in 3D mode for either 10 (n=4) or 10 and 20 minutes (n=2) to measure glycolysis as given by standardized uptake values (SUV). Ex vivo en face evaluation of aortas from an atherosclerotic animal illustrated plaque distribution macroscopically, compared to a lean control animal. Although T2-TSE weighted imaging was most consistent, no one MRI sequence was preferable and superior to another for visualization and identification of the abdominal aorta. We found poor correlation between SUVs obtained from 10 and 20 minutes of reconstructed PET emission data. This can most likely be ascribed to intestinal movement. In conclusion multisequence MRI is recommended for optimal imaging of the abdominal aorta using MRI. Furthermore we found that 10 minutes of PET emission data seems adequate. This is the first study to demonstrate that the method of (18)F-FDG PET/MRI is feasible in minipig models of atherosclerosis, and therefore relevant in larger prospective studies. Perspectives of the method include correlation to e.g. aortic immunohistochemistry findings and a range of genomic and proteomic analyses.

AB - Novel hybrid 18-fluoro-deoxy-D-glucose ((18)F-FDG) based positron emission tomography (PET) and magnetic resonance imaging (MRI) has shown promise for characterization of atherosclerotic plaques clinically. The purpose of this study was to evaluate the method in a pre-clinical model of diet-induced atherosclerosis, based on the Göttingen minipig. Using (18)F-FDG PET/MRI the goal was to develop and create a new imaging method in an in vivo animal model for translational studies of atherosclerosis. We used a strategy of multisequence MRI for optimal anatomical imaging of the abdominal aortas of the pigs (n=4): T1-weighted turbo spin-echo (T1-TSE), T2-weighted turbo spin-echo (T2-TSE) and proton density imaging with and without fat saturation. (18)F-FDG PET emission data were collected from a single bed position of the abdominal aorta in 3D mode for either 10 (n=4) or 10 and 20 minutes (n=2) to measure glycolysis as given by standardized uptake values (SUV). Ex vivo en face evaluation of aortas from an atherosclerotic animal illustrated plaque distribution macroscopically, compared to a lean control animal. Although T2-TSE weighted imaging was most consistent, no one MRI sequence was preferable and superior to another for visualization and identification of the abdominal aorta. We found poor correlation between SUVs obtained from 10 and 20 minutes of reconstructed PET emission data. This can most likely be ascribed to intestinal movement. In conclusion multisequence MRI is recommended for optimal imaging of the abdominal aorta using MRI. Furthermore we found that 10 minutes of PET emission data seems adequate. This is the first study to demonstrate that the method of (18)F-FDG PET/MRI is feasible in minipig models of atherosclerosis, and therefore relevant in larger prospective studies. Perspectives of the method include correlation to e.g. aortic immunohistochemistry findings and a range of genomic and proteomic analyses.

M3 - Journal article

C2 - 25143863

SN - 2160-8407

VL - 4

SP - 448

EP - 458

JO - American Journal of Nuclear Medicine and Molecular Imaging

JF - American Journal of Nuclear Medicine and Molecular Imaging

IS - 5

ER -