MRI-based Score for Assessment of Bone Mineral Density in Operative Spine Patients

Abstract

Study Design. Retrospective comparison. Objective. The aim was to determine whether a previously developed magnetic resonance imaging (MRI)-derived bone mineral density (BMD) scoring system can differentiate between healthy and osteoporotic vertebrae and to validate this scoring system against quantitative computed tomography measurements. Summary of Background Data. BMD is an important preoperative consideration in spine surgery. Techniques to measure BMD are subject to falsely elevated values in the setting of spondylosis (dual-energy X-ray absorptiometry) or require significant exposure to radiation [quantitative computed tomography (QCT)]. Previous studies have shown that MRI may be utilized to measure bone quality using changes in the bone marrow signal observed on T1-weighted MRIs. Materials and Methods. Retrospective study of patients who underwent operative lumbar procedures at a single tertiary institution between 2016 and 2021 (n=61). Vertebral bone quality (VBQ) scores were measured by dividing the median signal intensities of L1–L4 by the signal intensity of cerebrospinal fluid on noncontrast T1W MRI. Demographic data, comorbidities, VBQ scores, and QCT-derived T scores and BMD of the lumbar spine were compared between healthy (T score ≥−1; n=21), osteopenic (−2.5 <T score < −1; n=21), and osteoporotic (T score ≤−2.5; n=19) cohorts using analysis of variance with post hoc Tukey test. Linear regression and receiver operating characteristic curve analyses were performed to assess the predictive value of VBQ scores. Pearson correlation test was used to evaluate the association between VBQ scores and QCT-derived measurements. Results. VBQ differentiated between healthy and osteoporotic groups (P=0.009). Receiver operating characteristic curve analysis revealed that a greater VBQ score was associated with presence of osteoporosis (area under the curve=0.754, P=0.006). Cutoff VBQ for osteoporosis was 2.6 (Youden index 0.484; sensitivity: 58%; specificity: 90%). VBQ scores weakly correlated with QCT-derived BMD (P=0.03, r=−0.27) and T scores (P=0.04, r=−0.26). Conclusion. This study attempted to further validate a previously developed MRI-based BMD scoring system against QCT-derived measurements. VBQ score was found to be a significant predictor of osteoporosis and could differentiate between healthy and osteoporotic vertebrae.

A meta-analysis of the value of MRI-based VBQ scores for evaluating osteoporosis

“…21 studies were excluded because they either did not report results of interest or from which 2×2 columnar data could not be extracted. Finally, 8 studies ( Kadri et al, 2022 ; Salzmann et al, 2022 ; Hao et al, 2023 ; Chang et al, 2021 ; Kim et al, 2023 ; Haffer et al, 2022 ; Huang et al, 2022 ; 王平川, 王俊武, 石鹏志, 等, 2022 ) that involved 999 patients were included in this study.

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Association Between Vertebral Bone Quality Score and Dual-Energy X-ray Absorptiometry for the Assessment of Bone Mineral Density in Adolescent Patients

“…We did not find any other variable, such as age or BMI, that was independently associated with the VBQ score other than DEXA-derived BMD and Z-scores. There are several other studies that show the association between VBQ scores and DEXA scores and the ability of VBQ scores to differentiate between healthy and osteoporotic or osteopenic bones [ 11 , 14 , 15 , 17 , 18 ]. However, this association is unknown in a pediatric population [ 16 ].…”

In Response: MRI-based Score for Assessment of Bone Mineral Density in Operative Spine Patients

“…esponse to the letter: We appreciate our colleagues for the insightful comments on our study "MRIbased Score for Assessment of Bone Mineral Density in Operative Spine Patients" 1 and the opportunity to respond to their concerns. The commentators discuss that a dual-energy x-ray absorptiometry (DXA) T-score of −2.5 is not suitable for quantitative computed tomography (QCT), as it would likely overestimate the number of patients with osteoporosis.…”

“…Response to the letter: We appreciate our colleagues for the insightful comments on our study “MRI-based Score for Assessment of Bone Mineral Density in Operative Spine Patients” 1 and the opportunity to respond to their concerns.…”