Bandirali Michele, Di Leo Giovanni, Papini Giacomo Davide Edoardo, Messina Carmelo, Sconfienza Luca Maria, Ulivieri Fabio Massimo, Sardanelli Francesco
Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, via Festa del Perdono 7, 20122, Milano, Italy,
Eur Radiol. 2015 Oct;25(10):2951-9. doi: 10.1007/s00330-015-3699-y. Epub 2015 Apr 22.
Signal intensity of lumbar-spine at magnetic resonance imaging (MRI) correlates to bone mineral density (BMD). Our aim was to define a quantitative MRI-based score to detect osteoporosis on lumbar-spine MRI.
After Ethics Committee approval, we selected female patients who underwent both lumbar-spine MRI and dual-energy X-ray absorptiometry (DXA) and a reference group of 131 healthy females (20-29 years) who underwent lumbar-spine MRI. We measured the intra-vertebral signal-to-noise ratio in L1-L4. We introduced an MRI-based score (M-score), on the model of T-score. M-score diagnostic performance in diagnosing osteoporosis was estimated against DXA using receiver operator characteristic (ROC) analysis.
We included 226 patients (median age 65 years), 70 (31%) being osteoporotic at DXA. MRI signal-to-noise ratio correlated to BMD (r = -0.677, P < 0.001). M-score negatively correlated to T-score (r = -0.682, P < 0.001). Setting a 90%-specificity, an M-score threshold of 5.5 was found, distinguishing osteoporosis from non-osteoporosis (sensitivity 54%; ROC AUC 0.844). Thirty-one (14%) patients had a fragility fracture, with osteoporosis detected in 15 (48%) according to M-score and eight (26%) according to T-score (P = 0.016).
M-score obtained on lumbar spine MRI is a quantitative method correlating with osteoporosis. Its diagnostic value remains to be demonstrated on a large prospective cohort of patients.
• M-score is a quantitative score potentially screening osteoporosis on lumbar-spine MRI; • This method showed good intra- and inter-reader reproducibility; • M-score may be used for identifying patients who should undergo DXA.
腰椎磁共振成像（MRI）的信号强度与骨密度（BMD）相关。我们的目的是定义一种基于MRI的定量评分，以在腰椎MRI上检测骨质疏松症。
经伦理委员会批准后，我们选择了同时接受腰椎MRI和双能X线吸收法（DXA）检查的女性患者，以及一组131名接受腰椎MRI检查的健康女性（20 - 29岁）作为参照组。我们测量了L1 - L4椎体的信噪比。我们以T值模型为基础引入了一种基于MRI的评分（M评分）。使用受试者工作特征（ROC）分析，根据DXA评估M评分在诊断骨质疏松症方面的诊断性能。
我们纳入了226例患者（中位年龄65岁），其中70例（31%）经DXA诊断为骨质疏松症。MRI信噪比与BMD相关（r = -0.677，P < 0.001）。M评分与T值呈负相关（r = -0.682，P < 0.001）。设定特异性为90%时，发现M评分阈值为5.5，可区分骨质疏松症与非骨质疏松症（敏感性54%；ROC曲线下面积0.844）。31例（14%）患者发生脆性骨折，根据M评分，15例（48%）检测出骨质疏松症，根据T值，8例（26%）检测出骨质疏松症（P = 0.016）。
腰椎MRI获得的M评分是一种与骨质疏松症相关的定量方法。其诊断价值仍有待在大量前瞻性患者队列中得到证实。
• M评分是一种可能用于在腰椎MRI上筛查骨质疏松症的定量评分；• 该方法在阅片者内和阅片者间显示出良好的可重复性；• M评分可用于识别应接受DXA检查的患者。
