title: T1ρ magnetic resonance imaging and discography pressure as novel biomarkers for disc degeneration and low back pain.
abstract: METHODS
  Prospective magnetic resonance imaging (MRI) study of patients low back pain (LBP) requiring discography as part of their routine clinical diagnoses and asymptomatic age-matched volunteers.
  
  
  OBJECTIVE
  To determine whether T1ρ MRI and discography opening pressure (OP) are quantitative biomarkers of disc degeneration in LBP patients and in asymptomatic volunteers.
  
  
  BACKGROUND
  Disc degenerative disease, a common cause of LBP, is related to the patient's prognosis and serves as a target for therapeutic interventions. However, there are few quantitative measures in the clinical setting. Discography OP and T1ρ MRI are potential biomarkers of disc degenerative disease related to biochemical composition of the intervertebral disc.
  
  
  METHODS
  The institutional review board approved all experiments, and informed consent was provided by each subject. Patients being treated for LBP (n = 17; 68 levels; mean age, 44 ± 6 years; and range, 30-53) and control subjects (n = 11; 44 levels; mean age, 43 ± 17 years; and range, 22-76) underwent T1ρ and T2 MRI on a Siemens 3T Tim Trio clinical scanner (Siemens Medical Solutions, Malvern, PA). The LBP patients also received multilevel provocative discography before their MRI. OP was recorded as the pressure when fluid first enters the nucleus of the intervertebral disc.
  
  
  RESULTS
  T1ρ was significantly lower in the painful discs (55.3 ± 3.0 ms, mean ± SE) from control (92.0 ± 4.9 ms, P < 0.001) and nonpainful discs (83.6 ± 3.2 ms, P < 0.001). Mean OP for the painful discs (11.8 ± 1.0 psi, mean ± SE) was significantly lower than that for nonpainful discs (19.1 ± 0.7 psi, P < 0.001). Both T1ρ and OP correlated moderately with Pfirrmann degenerative grade. Receiver-operating-characteristic area under the curve was 0.91 for T1ρ MRI and 0.84 for OP for predicting painful discs.
  
  
  CONCLUSIONS
  T1ρ and OP are quantitative measures of degeneration that are consistent across both control subjects and LBP patients. A significant and strong correlation exists between T1ρ values and in vivo OP measurements obtained by discography in LBP patients.
authors.affiliation: Center for Magnetic Resonance & Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia 19104, USA. borthaku@upenn.edu
authors.forename: Arijitt
authors.initials: A
authors.lastname: Borthakur
authors.forename: Philip M
authors.initials: PM
authors.lastname: Maurer
authors.forename: Matthew
authors.initials: M
authors.lastname: Fenty
authors.forename: Chenyang
authors.initials: C
authors.lastname: Wang
authors.forename: Rachelle
authors.initials: R
authors.lastname: Berger
authors.forename: Jonathon
authors.initials: J
authors.lastname: Yoder
authors.forename: Richard A
authors.initials: RA
authors.lastname: Balderston
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Elliott
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D055959:Intervertebral Disc Degeneration / Q000150:complications / Q000503:physiopathology*; D017116:Low Back Pain / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011312:Pressure; D011446:Prospective Studies; D011859:Radiography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult