MRI-based vertebral bone quality score: relationship with age and reproducibility

Daniel Liu; Aamir Kadri; Diego Hernando; Neil Binkley; Paul A Anderson

doi:10.1007/s00198-023-06893-6

MRI-based vertebral bone quality score: relationship with age and reproducibility

Osteoporos Int. 2023 Dec;34(12):2077-2086. doi: 10.1007/s00198-023-06893-6. Epub 2023 Aug 29.

Authors

Daniel Liu¹, Aamir Kadri², Diego Hernando³, Neil Binkley⁴, Paul A Anderson⁵

Affiliations

¹ Department of Orthopedics and Rehabilitation, School of Medicine and Public Health, University of Wisconsin, 600 Highland Ave, Madison, WI, 53792-3252, USA. dliu83@wisc.edu.
² Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky College of Medicine, Lexington, KY, USA.
³ Department of Radiology and Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
⁴ Osteoporosis Clinical Research Program, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
⁵ Department of Orthopedics and Rehabilitation, School of Medicine and Public Health, University of Wisconsin, 600 Highland Ave, Madison, WI, 53792-3252, USA.

PMID: 37640844
DOI: 10.1007/s00198-023-06893-6

Abstract

Vertebral bone quality (VBQ) score is an opportunistic measure of bone mineral density using routine preoperative MRI in spine surgery. VBQ score positively correlates with age and is reproducible across serial scans. However, extrinsic factors, including MRI machine and protocol, affect the VBQ score and must be standardized.

Purpose: The purposes of this study were to determine whether VBQ score increased with age and whether VBQ remained consistent across serial MRI studies obtained within 3 months.

Methods: This retrospective study evaluated 136 patients, age 20-69, who received two T1-weighted lumbar MRI within 3 months of each other between January 2011 and December 2021. VBQ(L1-4) score was calculated as the quotient of L1-L4 signal intensity (SI) and L3 cerebral spinal fluid (CSF) SI. VBQ(L1) score was calculated as the quotient of L1 SI and L1 CSF SI. Regression analysis was performed to determine correlation of VBQ(L1-4) score with age. Coefficient of variation (CV) was used to determine reproducibility between VBQ(L1-4) scores from serial MRI scans.

Results: One hundred thirty-six patients (mean ± SD age 44.9 ± 12.5 years; 53.7% female) were included in this study. Extrinsic factors affecting the VBQ score included patient age, MRI relaxation time, and specific MRI machine. When controlling for MRI relaxation/echo time, the VBQ(L1-4) score was positively correlated with age and had excellent reproducibility in serial MRI with CV of 0.169. There was excellent agreement (ICC > 0.9) of VBQ scores derived from the two formulas, VBQ(L1) and VBQ(L1-4).

Conclusion: Extrinsic factors, including MRI technical factors and age, can impact the VBQ(L1-4) score and must be considered when using this tool to estimate bone mineral density (BMD). VBQ(L1-4) score was positively correlated with age. Reproducibility of the VBQ(L1-4) score across serial MRI is excellent especially when controlling for technical factors, supporting use of the VBQ score in estimating BMD. The VBQ(L1) score was a reliable alternative to the VBQ(L1-4) score.

Keywords: Bone health optimization; Magnetic resonance imaging; Opportunistic screening; Orthopedic surgery; Osteoporosis; Spine surgery.

MeSH terms

Adult
Bone Density*
Child, Preschool
Female
Humans
Infant
Lumbar Vertebrae* / diagnostic imaging
Magnetic Resonance Imaging / methods
Male
Middle Aged
Reproducibility of Results
Retrospective Studies