Whole-body positron emission tomography: Part I. Methods and performance characteristics

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Oncology

Background:

• Whole-body positron emission tomography (PET) imaging is crucial for cancer detection and staging.
• Current PET scans often use only a fraction of collected data, potentially limiting image quality.
• Extending the field of view (FOV) requires multiple bed positions for comprehensive body coverage.

Purpose of the Study:

• To develop and evaluate a whole-body PET imaging method utilizing 100% of projection data.
• To assess the image quality, contrast, and resolution achievable with this novel data acquisition approach.
• To determine optimal acquisition parameters for efficient whole-body PET scans.

Main Methods:

• Collected 100% of projection data, unlike typical rectilinear PET scans.
• Generated 2D projection images from resorted sinogram data over continuous angles (180 degrees).
• Reconstructed 3D tomographic images using filtered backprojection (FBP) without attenuation correction, extracting coronal and sagittal views.

Main Results:

• Both 2D projection and 3D tomographic image formation methods yielded high-quality images.
• Tomographic reconstruction provided superior contrast and resolution (10.8 mm) compared to 2D projections.
• Optimal imaging parameters identified: 1-2 min/bed position post-injection of 10 mCi [18F]fluoride ion or [18F]FDG, totaling 32-64 min scan time.

Conclusions:

• Utilizing 100% of projection data in whole-body PET imaging significantly enhances image quality.
• Filtered backprojection reconstruction offers high contrast and resolution for cancer imaging.
• Efficient whole-body PET scans are achievable with short acquisition times, improving clinical utility.