Beschreibung:
<jats:sec><jats:title>Purpose</jats:title><jats:p>To assess glycosaminoglycan (GAG) content of lumbar intervertebral discs (IVD) in patients with spondyloarthritis (SpA) using glycosaminoglycan chemical exchange saturation transfer (gagCEST).</jats:p></jats:sec><jats:sec><jats:title>Materials and Methods</jats:title><jats:p>Ninety lumbar intervertebral discs of nine patients with SpA and nine age‐matched healthy controls (eight patients with ankylosing spondylitis; one patient with spondylitis related to inflammatory bowel disease; mean age: 44.1 ± 14.0 years; range: 27–72 years) were examined with a 3T magnetic resonance imaging (MRI) scanner in this prospective study. The MRI protocol included standard morphological, sagittal <jats:italic>T</jats:italic><jats:sub>2</jats:sub>‐weighted (<jats:italic>T</jats:italic><jats:sub>2</jats:sub>w) images to assess Pfirrmann score of the five lumbar IVDs (L1 to S1) and biochemical imaging with gagCEST to calculate a region of interest analysis of nucleus pulposus (NP) and annulus fibrosus (AF). Prior to statistical testing of gagCEST effects (MTR<jats:sub>asym</jats:sub> values in percent) in patients and controls, IVDs were classified according to the Pfirrmann score.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Significantly lower gagCEST values of NP and AF were found in SpA patients compared with healthy volunteers (NP: 1.41% ± 0.41%, <jats:italic>P</jats:italic> = 0.001; 95% confidence interval, CI [0.600%–2.226%]; AF: 1.19% ± 0.32%, <jats:italic>P</jats:italic> < 0.001; CI [0.560%–1.822%]) by comparing the differences of the means. Pooled nondegenerative IVDs (Pfirrmann 1 and 2) had significantly lower gagCEST effects in patients suffering from SpA compared with healthy controls in NP (<jats:italic>P</jats:italic> < 0.001; CI [1.176%–2.337%]) and AF (<jats:italic>P</jats:italic> < 0.001; CI [0.858%–1.779%]). No significant difference of MTR<jats:sub>asym</jats:sub> values was found in degenerative IVDs between patients and controls in NP (<jats:italic>P</jats:italic> = 0.204; CI [–0.504%–2.170%]).</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>GagCEST analysis of morphologically nondegenerative IVDs (Pfirrmann score 1 and 2) in <jats:italic>T</jats:italic><jats:sub>2</jats:sub>w images demonstrated significantly lower GAG values in patients with spondyloarthritis in NP and AF, possibly representing a depletion of GAG in spondyloarthritis in the absence of morphologic degeneration.J. Magn. Reson. Imaging 2015. J. Magn. Reson. Imaging 2015;42:1057–1063.</jats:p></jats:sec>