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Hybrid PET/MRI Imaging of Alzheimer's Disease Based on 18F-AV-1451
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Image-Based 2D Re-Projection for Attenuation Substitution in PET Neuroimaging
Charles M Laymon1,2, Davneet S Minhas3, Carl R Becker3
1Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA. CML14@pitt.edu.
Molecular Imaging and Biology
|March 1, 2018
Summary
A new re-projection method enables applying alternate attenuation correction (AC) to positron emission tomography (PET)/magnetic resonance imaging (MRI) scans offline. This image-based reprocessing significantly reduced errors compared to standard methods, improving neuroimaging accuracy.
Area of Science:
- Medical Imaging
- Nuclear Medicine
- Radiophysics
Background:
- Dual modality PET/MRI combines anatomical and functional imaging.
- Accurate attenuation correction (AC) is crucial for quantitative PET imaging.
- Existing MR data can generate AC, but typically requires new reconstruction.
Purpose of the Study:
- To evaluate an approximate 2D projection method for offline, image-based reprocessing of PET/MRI AC.
- To assess the viability of applying alternate AC methods without full re-acquisition.
Main Methods:
- Acquired [18F]FDG PET/MRI brain scans on Siemens HR+ and mMR scanners.
- Generated MR-based AC (MRAC) from Dixon sequences and compared it to scanner-based AC (SAC).
- Implemented a re-projection method to substitute MRAC with SAC in reconstructed PET data (SUBAC PET).
Main Results:
- SUBAC PET demonstrated a substantially lower root mean square error (1.5%) compared to MRAC PET (8.1%).
- Regional activity concentrations were extracted from SAC PET, MRAC PET, and SUBAC PET for comparison.
Conclusions:
- The re-projection method is a viable approach for applying alternate AC in neuroimaging.
- This image-based reprocessing allows for offline AC updates, enhancing flexibility and accuracy in PET/MRI studies.
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