Intervertebral disc internal deformation measured by displacements under applied loading with MRI at 3T

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Biomechanics

Background:

• Noninvasive assessment of tissue mechanical properties is crucial for understanding tissue function in health and disease.
• Magnetic Resonance Imaging (MRI) offers potential for biomechanical characterization through displacement measurements under applied loading.

Purpose of the Study:

• To translate dual MRI (dualMRI) from research systems to a 3T clinical platform.
• To evaluate the precision of dualMRI for biomechanical characterization.
• To demonstrate dualMRI's capability in assessing tissue mechanics in vivo.

Main Methods:

• dualMRI technique was adapted for a 3T clinical MRI system.
• Precision was quantified using a silicone phantom with repeated measurements.
• Displacements and strains were visualized in an intervertebral disc and compared with T2 values during cyclic loading.

Main Results:

• Achieved displacement precision of 24 µm and strain precision of 0.3% under the tested imaging parameters.
• Successfully measured displacements and strains within an intervertebral disc.
• No significant correlation was observed between measured strains and T2 values.

Conclusions:

• The successful translation of dualMRI to a 3T clinical system enables potential for in vivo studies across various tissues and organs.
• dualMRI on a clinical platform is anticipated to be a valuable tool for assessing the interplay of structure, mechanics, and function in healthy and diseased tissues.