Visualising the 3D microstructure of stained and native intervertebral discs using X-ray microtomography.

Area of Science:

• Biomedical Engineering
• Radiology
• Orthopedics

Background:

• Intervertebral disc degeneration (IVDD) is a major cause of low back pain.
• Current 3D imaging methods for IVD microstructure are limited by specimen size and preparation artifacts.

Purpose of the Study:

• To develop micro computed X-ray tomography (microCT) methods for high-resolution 3D imaging of intervertebral disc (IVD) microstructure.
• To minimize sample preparation artifacts in IVD imaging.

Main Methods:

• Exploration of microCT techniques, including staining and phase contrast, on bovine tail IVDs.
• Comparison of laboratory and synchrotron X-ray sources.
• Evaluation of imaging results with and without chemical fixation and staining.

Main Results:

• Staining enhanced contrast but induced structural changes and incomplete region staining.
• Phase contrast microCT of unstained, chemically fixed samples resolved key IVD structures (nucleus pulposus, annulus fibrosus, lamellae, collagen bundles).
• Native tissue scans showed slightly lower contrast but were artifact-free.

Conclusions:

• Phase contrast microCT is a promising artifact-free method for visualizing soft tissue microstructure in IVDs.
• This technique may enable characterization of structural remodeling and in situ mechanical property studies of native tissues.