HR-pQCT cross-calibration using standard vs. Laplace-Hamming binarization approach

Area of Science:

• * Medical Imaging
• * Bone Biology
• * Biomedical Engineering

Background:

• * High-resolution peripheral quantitative computed tomography (HR-pQCT) is vital for assessing bone microarchitecture.
• * Transitioning between HR-pQCT scanner generations (XCTI to XCTII) complicates longitudinal and multi-center studies.
• * Cross-calibration is essential for integrating data from different HR-pQCT devices.

Purpose of the Study:

• * To establish cross-calibration equations for estimating XCTII HR-pQCT measurements from XCTI data.
• * To compare standard vs. Laplace-Hamming (LH) binarization for XCTII data when cross-calibrating with XCTI.
• * To facilitate the comparison and utilization of historical HR-pQCT bone data.

Main Methods:

• * Scanned radii and tibiae of 36 volunteers on both XCTI and XCTII HR-pQCT scanners.
• * Analyzed XCTI images using the standard protocol.
• * Analyzed XCTII images using both standard and Laplace-Hamming (LH) binarization methods.
• * Employed linear regression to derive cross-calibration equations.

Main Results:

• * Strong correlations were found between XCTI and XCTII for bone density and geometry outcomes.
• * Most microstructural outcomes showed strong correlations despite absolute value differences.
• * The LH binarization approach for XCTII improved correlations and reduced bias for resolution-sensitive measures compared to the standard XCTII protocol when compared to XCTI data.

Conclusions:

• * Cross-calibration equations enable the estimation of XCTII measurements from XCTI data.
• * The Laplace-Hamming (LH) binarization method is recommended for XCTII analysis, especially for comparing with XCTI data.
• * Utilizing the LH approach enhances accuracy and comparability of bone microarchitecture data across HR-pQCT scanner generations.