title: A new diagnostic score to detect osteoporosis in patients undergoing lumbar spine MRI.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  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.
  
  
  CONCLUSIONS
  • 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.
authors.affiliation: Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, via Festa del Perdono 7, 20122, Milano, Italy, michele.bandirali@hotmail.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Bandirali
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Leo
authors.forename: Giacomo Davide Edoardo
authors.initials: GD
authors.lastname: Papini
authors.forename: Carmelo
authors.initials: C
authors.lastname: Messina
authors.forename: Luca Maria
authors.initials: LM
authors.lastname: Sconfienza
authors.forename: Fabio Massimo
authors.initials: FM
authors.lastname: Ulivieri
authors.forename: Francesco
authors.initials: F
authors.lastname: Sardanelli
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000368:Aged; D015519:Bone Density / Q000502:physiology; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D010024:Osteoporosis / Q000175:diagnosis* / Q000503:physiopathology; D058866:Osteoporotic Fractures / Q000175:diagnosis / Q000503:physiopathology; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D059629:Signal-To-Noise Ratio