Abstract 17980: Evaluation of Attenuation Correction in Cardiac PET using PET/MR
Background: Simultaneous acquisition Positron Emission Tomography / Magnetic Resonance (PET/MR) is a new technology that has potential as a tool both in research and clinical diagnosis. However, cardiac PET acquisitions have not yet been fully validated using MR imaging for attenuation correction (AC). The goal of this study is to evaluate the feasibility of PET imaging using a standard 2-point Dixon VIBE (Volume Interpolated Breathhold Examination) MR sequence for attenuation correction.
Materials and Methods: AC evaluation was performed in both phantoms and patients. A chest phantom containing heart and lung inserts was scanned by both PET/MR and PET/CT to assess the effect of the attenuation from the phased array coil, PET reconstruction accuracy, and the effect of the fixed attenuation u-value of the lungs. In addition, 30 patients underwent whole-body 18F-Fluorodeoxyglucose PET/CT (~60 min post-injection) followed by simultaneous cardiac PET/MR (~120 min post-injection).
Results: Phantom study showed excellent agreement between the two scanners. The relative change of activity in the myocardium due to the attenuation from the MR coil was of the order of 3% while a change of lung density from 0.0175cm-1 to 0.0289cm-1 (nominal value 0.0224 cm-1) resulted in a change of 1%. There was excellent per patient correlation between the values acquired by PET/CT and PET/MR (R2 =0.97) with a slope of 1.24 that can be attributed to continued FDG uptake between the two scans.
Conclusion: Myocardial SUV on PET imaging using MR for AC shows excellent correlation with myocardial SUV obtained by standard PET/CT imaging. The 2-point Dixon VIBE MR technique can be used for AC in simultaneous PET/MR data acquisition.
Author Disclosures: M. Lau: None. R. Laforest: None. H. Sotoudeh: None. X. Nie: None. S. Sharma: None. J. McConathy: None. A. Priatna: Employment; Modest; Employed by Siemens Medical Solutions. R. Gropler: None. P. Woodard: None.
- © 2014 by American Heart Association, Inc.