Liu Daniel, Kadri Aamir, Hernando Diego, Binkley Neil, Anderson Paul A
Department of Orthopedics and Rehabilitation, School of Medicine and Public Health, University of Wisconsin, 600 Highland Ave, Madison, WI, 53792-3252, USA.
Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky College of Medicine, Lexington, KY, USA.
Osteoporos Int. 2023 Dec;34(12):2077-2086. doi: 10.1007/s00198-023-06893-6. Epub 2023 Aug 29.
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.
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.
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.
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).
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.
椎体骨质量（VBQ）评分是脊柱手术中利用术前常规MRI对骨密度进行的一种机会性测量。VBQ评分与年龄呈正相关，并且在连续扫描中具有可重复性。然而，包括MRI机器和检查方案在内的外部因素会影响VBQ评分，必须进行标准化。
本研究的目的是确定VBQ评分是否随年龄增长而增加，以及在3个月内进行的连续MRI研究中VBQ是否保持一致。
这项回顾性研究评估了136例年龄在20 - 69岁之间的患者，这些患者在2011年1月至2021年12月期间彼此间隔3个月内接受了两次T1加权腰椎MRI检查。VBQ（L1 - 4）评分计算为L1 - L4信号强度（SI）与L3脑脊液（CSF）SI的商。VBQ（L1）评分计算为L1 SI与L1 CSF SI的商。进行回归分析以确定VBQ（L1 - 4）评分与年龄的相关性。变异系数（CV）用于确定连续MRI扫描中VBQ（L1 - 4）评分之间的可重复性。
本研究纳入了136例患者（平均年龄±标准差44.9±12.5岁；53.7%为女性）。影响VBQ评分的外部因素包括患者年龄、MRI弛豫时间和特定的MRI机器。在控制MRI弛豫/回波时间时，VBQ（L1 - 4）评分与年龄呈正相关，并且在连续MRI中具有出色的可重复性，CV为0.169。由VBQ（L1）和VBQ（L1 - 4）这两个公式得出的VBQ评分具有出色的一致性（组内相关系数>0.9）。
包括MRI技术因素和年龄在内的外部因素会影响VBQ（L1 - 4）评分，在使用该工具估计骨密度（BMD）时必须予以考虑。VBQ（L1 - 4）评分与年龄呈正相关。VBQ（L1 - 4）评分在连续MRI中的可重复性非常好，尤其是在控制技术因素时，支持将VBQ评分用于估计BMD。VBQ（L1）评分是VBQ（L1 - 4）评分的可靠替代方法。
