Image-based finite element model stiffness and vBMD by single and dual energy CT reconstruction kernel

Area of Science:

• Medical Imaging
• Biomechanical Engineering
• Radiology

Background:

• Single-energy quantitative computed tomography (SEQCT) and dual-energy CT (DECT) are used for bone mineral density (vBMD) assessment.
• Reconstruction kernels and energy settings can influence vBMD accuracy.
• vBMD is critical for bone analysis and input into finite element models (FEMs).

Purpose of the Study:

• To compare vBMD and FEM stiffness derived from SEQCT and DECT images reconstructed with standard (STD) and boneplus (BONE) kernels.
• To evaluate the impact of CT imaging parameters on bone mechanical properties.

Main Methods:

• SEQCT and DECT scans of cadaveric shoulders (n=10) were acquired.
• Images were reconstructed using STD and BONE kernels.
• vBMD was calculated using specimen-specific calibrations.
• FEMs were generated from proximal humerus sections for stiffness analysis.

Main Results:

• The BONE kernel consistently yielded higher vBMD than the STD kernel across both SEQCT and DECT.
• Significant differences in vBMD were observed in DECT images (p=0.001).
• FEM stiffness was higher with the BONE kernel; differences between STD and BONE were similar for SEQCT and DECT.

Conclusions:

• CT imaging parameters, specifically reconstruction kernels, significantly alter vBMD and FEM stiffness.
• Consistent imaging protocols are essential for accurate vBMD and FEM analysis.
• Inconsistent parameters can lead to systematic measurement errors in bone biomechanics research.