title: Magnetization transfer ratio mapping of intervertebral disc degeneration.
abstract: The magnetization transfer ratio of the lumbar discs was spatially quantified from age-matched subjects and the nucleus pulposus magnetization transfer ratio was correlated with T2-weighted Pfirrmann grades. A moderate and significant linear correlation between magnetization transfer ratio and Pfirrmann grades was observed, suggesting that nucleus pulposus collagen relative density increases with degeneration. High-resolution axial magnetization transfer ratio maps revealed elevated magnetization transfer ratio in the nucleus pulposa of injured and heavily degenerated discs. In the injured disc, significant elevation in nucleus pulposa magnetization transfer ratio was not accompanied by significant decrease in disc height. This observation may suggest a possible increase in absolute collagen content, in addition to increased collagen relative density. In summary, magnetization transfer MRI of the disc may serve as a noninvasive diagnostic tool for disc degeneration, in addition to other MRI techniques specific to proteoglycan content.
authors.affiliation: Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6100, USA. wangch@seas.upenn.edu
authors.forename: Chenyang
authors.initials: C
authors.lastname: Wang
authors.forename: Walter
authors.initials: W
authors.lastname: Witschey
authors.forename: Ari
authors.initials: A
authors.lastname: Goldberg
authors.forename: Mark
authors.initials: M
authors.lastname: Elliott
authors.forename: Arijitt
authors.initials: A
authors.lastname: Borthakur
authors.forename: Ravinder
authors.initials: R
authors.lastname: Reddy
mesh_terms: D000465:Algorithms; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D055959:Intervertebral Disc Degeneration / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity