title: Contrast-enhanced MRI for detecting intravertebral cleft formation: relation to the time since onset of vertebral fracture.
abstract: OBJECTIVE
  The purpose of this study was to investigate the advantages of contrast-enhanced MRI (CE-MRI) for detecting intravertebral clefts over unenhanced MRI in relation to the time since onset of vertebral fracture.
  
  
  METHODS
  In this retrospective study, a total of 115 patients (88 women, 27 men; mean age, 77.1 years) who underwent percutaneous vertebroplasty for a single-level compression fracture within 7 days of preprocedural MRI were enrolled. Two radiologists evaluated preprocedural unenhanced MRI (T1-weighted and STIR) and CE-MRI examinations for intravertebral clefts on separate days by consensus. The time from the onset of fracture to MRI was classified into three groups: early phase fractures (< 1 month), late phase fractures (1-3 months), and chronic phase fractures (≥ 3 months). The cement distribution during percutaneous vertebroplasty was used as a reference standard, and detectability of clefts was compared between unenhanced MRI and CE-MRI in relation to the time frame. An analog of the McNemar test was used for analyses.
  
  
  RESULTS
  There were 104 patients (90.4%) with and 11 patients (9.6%) without a cleft. The sensitivities of unenhanced MRI and CE-MRI, respectively, for detecting clefts were 60.9% and 91.3% for early phase fractures (p = 0.02); 78.6% and 100% for late phase fractures (p = 0.014); and 92.5% and 94.3% for chronic phase fractures (p = 0.3). The specificities were the same for both groups (100% for each time frame).
  
  
  CONCLUSIONS
  CE-MRI is more sensitive than unenhanced MRI for detecting intravertebral clefts in patents with benign compression fractures less than 3 months old.
authors.affiliation: Department of Radiology, St. Luke's International Hospital, Akashi-cho 9-1, Chuo-ku, Tokyo 104-8560 Japan. mitishi@luke.or.jp
authors.forename: Mitsutomi
authors.initials: M
authors.lastname: Ishiyama
authors.forename: Yuji
authors.initials: Y
authors.lastname: Numaguchi
authors.forename: Akari
authors.initials: A
authors.lastname: Makidono
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Sokun
authors.initials: S
authors.lastname: Fuwa
authors.forename: Sachiko
authors.initials: S
authors.lastname: Ohde
authors.forename: Yukihisa
authors.initials: Y
authors.lastname: Saida
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D005260:Female; D050815:Fractures, Compression / Q000175:diagnosis* / Q000601:surgery*; D005682:Gadolinium; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016103:Spinal Fractures / Q000175:diagnosis* / Q000601:surgery*; D013997:Time Factors; D054854:Vertebroplasty
chemical_list: D003287:Contrast Media; D005682:Gadolinium