programma & abstracts - Nederlandse Vereniging voor Radiologie

MSK/Thorax/Diversen 10
O10.2
CT-ARTHROGRAPHY TO MEASURE
CARTILAGE QUALITY: INFLUENCE OF
SULPHATED GLYCOSAMINOGLYCAN
CONTENT AND STRUCTURAL
COMPOSITION OF EXTRACELLULAR
MATRIX ON CONTRAST AGENT DIFFUSION
INTO CARTILAGE
J. van Tiel, M. Siebelt, J.H. Waarsing, M. van Straten,
G.P. Krestin, H. Weinans, E.H.G. Oei
Erasmus Medisch Centrum, Rotterdam
Purpose: To assess the potential of CT-arthrography to
evaluate cartilage quality in terms of sulphated glycosaminoglycan
content (sGAG) and structural composition of the
extra-cellular matrix (ECM).
Methods: Eleven human cadaveric knee joints were
scanned on a second generation dual source spiral CT scanner
before and after intra-articular injection of a negatively
charged contrast agent. Mean X-ray attenuation values of
both scans were calculated in seven regions of interest
(ROIs) of the cartilage (weight-bearing condyles and plateaus,
non weight-bearing condyles and patella). Next, all
ROIs were rescanned with contrast-enhanced
micro-CT (μCT), which served as reference standard because
it accurately measures sGAG content and hence quality
of cartilage. Correlation between mean X-ray attenuation
values of CT-arthrography and μCT was analyzed with linear
regression. Additionally, residual values from the linear fit
between unenhanced CT and μCT were used as a covariate
measure to identify the influence of structural composition
of cartilage ECM, i.e. without influence of sGAG, on contrast
diffusion into cartilage.
Results: Mean X-ray attenuation of cartilage was
significantly higher for CT-arthrography compared to
unenhanced CT in all ROIs. Furthermore, CT-arthrography
attenuation values correlated excellently with reference
μCT values representing sGAG content of cartilage
(R=0.86;R2=0.73;p