title: The clinical influence of fluid sign in treated vertebral bodies after percutaneous vertebroplasty.
abstract: OBJECTIVE
  To determine the association between fluid sign and clinical prognosis following percutaneous vertebroplasty (PV).
  
  
  METHODS
  Institutional review board approval and informed consent were obtained for this prospective study. Fifty-two patients (41 women, 11 men; mean age, 75.9 years; range, 56-95 years) were enrolled from August 2006 to August 2007. All patients underwent preoperative magnetic resonance (MR) imaging and assessment of mobility and pain scores. PV was performed and patients underwent 1-, 3-, and 6-month follow-up examinations. MR findings of fluid sign (a focal, linear, or triangular area of strong hyperintensity, which is isointense relative to cerebrospinal fluid on T2-weighted sagittal images) and vacuum cleft were analyzed with respect to clinical outcome. Data were analyzed by using a combination of independent Student t test, chi(2) test, analysis of variance, and Fisher exact test.
  
  
  RESULTS
  Thirty-four (65%) patients showed vacuum cleft; 14 (27%) showed fluid sign at the bone-cement interface. Patients without fluid sign in the treated vertebral bodies had better mobility and pain improvement compared with patients with fluid sign at 1- and 3-month follow-up (P < .05). The adjacent fracture percentage (seven of 14, 50%) was higher in patients with fluid sign in the treated vertebral bodies than in those without (three of 38, 8%) (P = .002). Pain was similar in groups with and without fluid sign at 6-month follow-up.
  
  
  CONCLUSIONS
  The fluid sign in the treated vertebral bodies had a high negative predictive value of 92% and a positive predictive value of 50% to develop a new adjacent compression fracture.
authors.affiliation: Department of Radiology, China Medical University Hospital No. 2, Yuh-Der Road, Taichung 40447, Taiwan. lin.chaochu@msa.hinet.net
authors.forename: Chao-Chun
authors.initials: CC
authors.lastname: Lin
authors.forename: Shu-Hui
authors.initials: SH
authors.lastname: Wen
authors.forename: Cheng-Hui
authors.initials: CH
authors.lastname: Chiu
authors.forename: Ing-Ho
authors.initials: IH
authors.lastname: Chen
authors.forename: Tzai-Chiu
authors.initials: TC
authors.lastname: Yu