Single-sided NMR to estimate morphological parameters of the trabecular bone structure

Area of Science:

• Biophysics
• Medical Imaging
• Materials Science

Background:

• Trabecular bone morphology is crucial for skeletal integrity.
• Assessing bone structure often requires advanced imaging techniques like micro-CT.
• Non-invasive methods for evaluating bone microstructure are highly sought after.

Purpose of the Study:

• To develop and validate a single-sided ¹ H-NMR methodology for estimating trabecular bone morphological parameters.
• To assess intratrabecular and intertrabecular porosities without an external reference signal.
• To explore the potential for detecting pathophysiological alterations in bone structure.

Main Methods:

• Analysis of animal trabecular bone samples using a single-sided NMR device.
• Application of Carr-Purcell-Meiboom-Gill sequence to quantify ¹ H nuclei in bone fluids.
• Utilizing quasi-continuous T₂ distributions to separate fluid pools and estimate NMR parameters.
• Comparison of NMR-derived parameters with micro-CT measurements.

Main Results:

• The internal reference parameter (short T₂ signal intensity fraction) accurately predicted micro-CT parameters BV/TV and BS/TV (R > 0.80).
• Intratrabecular porosity was estimated at (33 ± 5)%.
• NMR-estimated BV/TV and BS/TV showed high linear correlation with micro-CT values (R > 0.90 and R > 0.80, respectively).

Conclusions:

• Single-sided ¹ H-NMR is a viable tool for preclinical assessment of trabecular bone morphology and porosity.
• Low-field, portable NMR devices offer a non-ionizing radiation alternative for in vitro studies.
• This technique has potential for detecting structural changes related to bone diseases.