Data-driven respiratory gating based on localized diaphragm sensing in TOF PET.
Kyungsang Kim1,2, Mengdie Wang1,2, Ning Guo1
1Gordon Center for Medical Imaging Department of Radiology Massachusetts General Hospital Harvard Medical School Boston MA 02114 United States of America.
Physics in Medicine and Biology
|May 27, 2020
Summary
Accurate respiratory gating in positron emission tomography (PET) is crucial for tumor imaging. This study introduces a new method using time-of-flight (TOF) PET and a diaphragm mask for improved breathing cycle detection, enhancing image quality.
Area of Science:
- Medical Imaging
- Nuclear Medicine
- Biophysics
Background:
- Accurate measurement of the respiratory cycle in Positron Emission Tomography (PET) is essential for improving tumor contrast and localization accuracy in organs like the lung and liver.
- Existing data-driven respiratory gating methods struggle with low signal-to-noise ratio (SNR) data, especially in low-dose PET/CT scans.
- Time-of-flight (TOF) PET offers higher SNR and better region-of-interest localization, making it suitable for respiratory gating.
Purpose of the Study:
- To propose an accurate data-driven respiratory gating method utilizing TOF PET information.
- To improve the accuracy of respiratory gating by retrospectively deriving the respiratory signal using a localized sensing method based on a diaphragm mask.
- To enhance the image quality and accuracy of tumor localization in PET scans.
Main Methods:
- Development of a novel data-driven respiratory gating method using TOF PET data.
- Implementation of a localized sensing method based on a diaphragm mask to derive the respiratory signal.
- Validation of the method using three patient datasets, comparing the derived respiratory signal against a pressure-belt signal as ground truth.
Main Results:
- The proposed method demonstrated a strong match with the pressure-belt respiratory signal, showing less than 5% peak time errors.
- Over 80% trace correlations were achieved between the proposed method's respiratory signal and the ground truth.
- Respiratory-gated images produced by the proposed method exhibited clearer organ edges compared to conventional non-TOF methods.
Conclusions:
- The proposed data-driven respiratory gating method significantly improves the accuracy of gating signals in TOF PET.
- The method enhances overall image quality, leading to better tumor localization and contrast.
- This technique offers a valuable advancement for low-dose PET/CT imaging, particularly in organs with significant respiratory motion.
