A method for synchronizing an external respiratory signal with a list-mode PET acquisition

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Biophysics

Background:

• Accurate synchronization of positron emission tomography (PET) list-mode data with physiological signals, particularly respiration, is crucial for motion correction.
• Traditional synchronization methods often rely on a master clock, which may not always be available or practical.
• External respiratory signals are commonly recorded but require precise alignment with PET data.

Purpose of the Study:

• To develop and validate a novel method for synchronizing PET list-mode data with an external respiratory signal.
• To achieve synchronization in the absence of a master clock, enhancing flexibility in data acquisition.
• To confirm the efficacy and reliability of the proposed synchronization technique across multiple clinical studies.

Main Methods:

• A trigger mark is stored in the PET list-mode file when the respiratory signal crosses a user-defined threshold.
• Synchronization is achieved post-acquisition by superimposing the stored trigger marks onto the respiratory curve.
• The method was tested on ten clinical studies using both Philips Gemini and GE DLS PET-CT systems.

Main Results:

• The proposed method successfully achieved synchronization in all ten clinical studies.
• Synchronization was found to be unequivocal, indicating high reliability.
• The method demonstrated effectiveness across different PET-CT system vendors.

Conclusions:

• The developed method provides a robust and reliable approach for synchronizing PET list-mode data with respiratory signals without a master clock.
• This technique enhances the quality of PET imaging by enabling accurate respiratory gating, leading to improved motion artifact correction.
• The findings support the widespread adoption of this method in clinical PET research and practice.