Qualitative and quantitative analysis of reduced bed position acquisition time on FDG PET image quality

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Radiology

Background:

• Optimizing Positron Emission Tomography-Computed Tomography (PET-CT) acquisition protocols is crucial for improving patient throughput and resource utilization.
• Evaluating the impact of reduced scan times on image quality is essential for maintaining diagnostic accuracy.

Purpose of the Study:

• To assess if reducing bed position acquisition time in PET-CT scans affects image quality.
• To compare the effects of Time of Flight (TOF) and Q.Clear reconstruction algorithms on image quality with reduced acquisition times.
• To investigate the influence of patient Body Mass Index (BMI) on image quality.

Main Methods:

• Retrospective analysis of 30 PET-CT scans performed on a new institutional scanner.
• Four reconstruction types were evaluated: 1 min 45 sec TOF, 2 min TOF, 1 min 45 sec Q.Clear, and 2 min Q.Clear.
• Qualitative assessment using a 5-point visual score on Maximum Intensity Projection (MIP) images and quantitative analysis of liver Signal-to-Noise Ratio (SNR).

Main Results:

• A statistically significant reduction in visual image quality scores was observed when decreasing bed position time from 2 min to 1 min 45 sec for both TOF (P=0.0002) and Q.Clear (P=0.02) reconstructions.
• Liver SNR also showed a statistically significant difference with reduced acquisition time.
• Image quality deterioration was minimized with reduced acquisition time when utilizing Q.Clear reconstruction.

Conclusions:

• Reducing PET-CT bed position acquisition time can be achieved with minimal clinical detriment to image quality, particularly when employing Q.Clear reconstruction.
• This protocol optimization holds potential for increasing scanning capacity without compromising diagnostic performance.
• Further investigation into the role of patient BMI in relation to these findings may be warranted.