Association of R2* with Fat Fraction and Bone Mineral Density in Osteoporosis Assessment

Overview

This study investigated the correlations between R2*, fat fraction (FF), and bone mineral density (BMD) in lumbar vertebrae of patients with chronic low back pain. Findings showed significant relationships among these parameters, suggesting that R2* combined with FF may enhance quantitative assessment of osteoporosis (OP).

Background

Osteoporosis is a prevalent age-related disease primarily diagnosed via BMD measurements. Bone marrow adipose tissue (BMAT) influences OP progression and may affect BMD accuracy, necessitating BMAT quantification. MRI techniques like IDEAL-IQ enable simultaneous acquisition of FF and R2* images, providing insights into bone marrow composition. While FF has been linked to BMD, the role of R2* in OP assessment remains controversial and underexplored.

Data Highlights

Key Findings

• FF and R2* values were reliably measured with good inter-reader agreement (ICC > 0.88).
• FF negatively correlates with BMD, consistent with previous studies indicating increased marrow fat with bone loss.
• R2* shows a significant correlation with both FF and BMD, suggesting it reflects changes in bone marrow composition and trabecular structure.
• Patients were stratified into normal BMD, osteopenia, and osteoporosis groups based on QCT measurements, enabling comparative analysis.
• ROC curve analysis demonstrated that combining FF and R2* improves diagnostic accuracy for osteoporosis compared to either parameter alone.

Clinical Implications

Incorporating R2* measurements alongside fat fraction via IDEAL-IQ MRI sequences may enhance the precision of osteoporosis diagnosis beyond traditional BMD assessment. This combined imaging approach could better characterize bone marrow changes and improve early detection and monitoring of OP in clinical practice.

Conclusion

The study supports the utility of R2* as a complementary biomarker to FF and BMD in quantitative osteoporosis assessment. Further validation may establish R2* as a valuable parameter in routine clinical evaluation of bone health.

References

1. Ergen et al. 2018 -- Correlation between Fat Fraction and BMD
2. Ji et al. 2019 -- BMAT Quantification and Disc Degeneration
3. Wang et al. 2023 -- IDEAL-IQ MRI in Bone Marrow Analysis