Effectiveness of Data-Driven Gating FDG PET/CT for Abdominal Region

Area of Science:

• Nuclear Medicine
• Medical Imaging
• Radiology

Background:

• Respiratory motion artifacts are a significant challenge in Positron Emission Tomography/Computed Tomography (PET/CT) imaging, potentially affecting diagnostic accuracy.
• MotionFree (MF) is a technique designed to mitigate respiratory motion during PET/CT scans.
• Evaluating the efficacy of MF across different PET/CT scanner platforms and abdominal regions is crucial for optimizing its clinical application.

Purpose of the Study:

• To validate the effectiveness of MotionFree (MF) in reducing respiratory motion artifacts in the abdominal region using two distinct PET/CT scanners.
• To determine optimal strategies for the efficient use of MF, considering factors like scanner type, lesion location, and lesion size.
• To assess the impact of MF on Standardized Uptake Value (SUV) measurements in abdominal lesions.

Main Methods:

• 198 patients underwent respiratory-gated ¹⁸F-FDG PET/CT with and without MF.
• Imaging was performed on Discovery MI (DMI) and Discovery IQ (DIQ) PET/CT scanners.
• Data were analyzed based on abdominal region (upper vs. lower), lesion size (<20 mm vs. ≥20 mm), and scanner type; physician assessment of motion artifact reduction and calculation of SUV change rate (ΔSUV) were conducted.

Main Results:

• MF reduced motion artifacts in 31.3% of upper abdomen scans and 0.5% of lower abdomen scans.
• Artifact reduction was more pronounced with the DMI scanner (52.0%) compared to the DIQ scanner (12.0%).
• Significant increases in ΔSUV were observed for lesions in the upper abdomen, smaller lesions (<20 mm), and with the DMI scanner, indicating improved lesion detectability and quantification.

Conclusions:

• MotionFree (MF) effectively reduces respiratory motion artifacts, especially in higher-spatial-resolution PET/CT images and for lesions in the upper abdomen.
• MF significantly increases SUV measurements for smaller lesions (<20 mm) and those in the upper abdomen across both tested PET/CT scanners.
• Applying MF to the upper abdomen is recommended to enhance SUV measurements and potentially reduce acquisition time, optimizing its clinical utility.