Supplemental Transmission Aided Attenuation Correction for Quantitative Cardiac PET

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Physics

Background:

• Quantitative positron emission tomography (PET) attenuation correction (AC) is crucial for cardiac PET/CT and PET/MR imaging.
• Accurate AC is challenging due to patient motion and complex anatomy.

Purpose of the Study:

• To propose and evaluate a novel AC approach for cardiac PET/CT and PET/MR.
• To enable accurate quantitative PET imaging without prior image data or assumptions.

Main Methods:

• Developed supplemental transmission aided maximum likelihood reconstruction of attenuation and activity (sTX-MLAA) algorithm.
• Utilized a weak, fixed external source and patient coincidences to reconstruct μ-maps based on physics principles.
• Fully corrected for scatter and randoms from both external source and patient.

Main Results:

• sTX-MLAA demonstrated ≤ 5% bias in activity concentrations compared to CT-based AC in phantom studies.
• Reduced PET background variability compared to using transmission source counts alone.
• Effective with a TX source strength ≥ 12.7 MBq.

Conclusions:

• sTX-MLAA provides accurate quantitative PET attenuation correction for cardiac imaging.
• The method is robust and does not rely on prior imaging data.
• Enables quantitative PET/CT and PET/MR in human patients.