Evaluation of frame-based and event-by-event motion-correction methods for awake monkey brain PET imaging

Area of Science:

• Neuroimaging
• Medical Physics
• Primate Research

Background:

• Positron Emission Tomography (PET) imaging in awake nonhuman primates (NHPs) is challenged by head motion.
• NHPs exhibit faster and more frequent head movements than humans, necessitating motion correction for accurate brain imaging.

Purpose of the Study:

• To design and validate two motion-correction algorithms for awake NHP brain PET imaging.
• To compare the efficacy of multiacquisition frame (MAF) and event-by-event (EBE) motion correction methods.

Main Methods:

• Implemented MAF and EBE motion-correction algorithms using externally tracked motion data.
• Evaluated algorithm accuracy with moving phantom scans.
• Applied methods to awake NHP brain PET studies using (11)C-flumazenil and compared with anesthetized studies.

Main Results:

• EBE motion correction recovered image contrast within 3% in phantom studies, while MAF showed a 25% reduction.
• EBE correction demonstrated superior recovery of fine structures in awake NHP PET images compared to MAF.
• NHP studies showed EBE correction significantly reduced blurring caused by intraframe motion.

Conclusions:

• EBE motion correction, utilizing accurate external motion data, effectively mitigates image blurring in awake NHP brain PET.
• The findings suggest EBE is a more suitable method for correcting significant head motion in NHP PET imaging than MAF.