Inter-scanner Aβ-PET harmonization using barrel phantom spatial resolution matching

Area of Science:

• Nuclear Medicine
• Medical Imaging
• Radiochemistry

Background:

• Standardized uptake value ratio (SUVR) measures amyloid beta-positron emission tomography (Aβ-PET) uptake in the brain.
• Variability in PET scanner technology and reconstruction techniques causes inconsistencies in Aβ-PET images.
• Harmonization is essential for consistent Aβ-PET measurements across multiple centers and scanners.

Purpose of the Study:

• To propose and validate an Aβ-PET harmonization method based on matching spatial resolution.
• To assess the consistency of Aβ-PET measurements across different PET scanners using phantom-derived spatial resolution.
• To improve the reliability of Aβ-PET quantitation in multi-center clinical trials.

Main Methods:

• Evaluated three PET scanners: Siemens Biograph Vision 600, Siemens Biograph mCT, and Philips Gemini TF64.
• Calculated the full-width at half-maximum (FWHM) using [18F]-filled barrel phantom scans for each scanner's reconstruction configuration.
• Assessed statistical similarity between regional SUVRs using paired t-tests on data from subjects scanned on multiple scanners.

Main Results:

• Specific FWHM values were identified for each scanner pair that maximized statistical similarity in regional SUVRs (e.g., Vision 4.10 mm vs. mCT 4.30 mm).
• Matched barrel phantom spatial resolutions (FWHM) between scanner pairs led to maximal harmonization of Aβ-PET quantitation.
• The method demonstrated effectiveness in harmonizing SUVRs across different scanner types and reconstruction settings.

Conclusions:

• Matching spatial resolution derived from barrel phantom scans effectively harmonizes Aβ-PET quantitation between PET scanner pairs.
• This harmonization technique enhances the consistency and validity of Aβ-PET measurements in multi-center studies.
• The proposed method offers a practical approach for ensuring reliable Aβ-PET data across different imaging sites and over time.