Christian Glaser MD, Presenter: Nothing to Disclose

Lucianna Filidoro Dipl Phys, Abstract Co-Author: Nothing to Disclose

Daniel Weber, Abstract Co-Author: Nothing to Disclose

Andreas Arnoldi, Abstract Co-Author: Nothing to Disclose

Juergen Weber PhD, Abstract Co-Author: Nothing to Disclose

Maximilian F. Reiser MD, Abstract Co-Author: Nothing to Disclose

José Raya MSc, Abstract Co-Author: Nothing to Disclose

Annie Horng MD, Abstract Co-Author: Nothing to Disclose

Peter Michael Jakob PhD, Abstract Co-Author: Nothing to Disclose

Reinhold Putz MD, Abstract Co-Author: Nothing to Disclose

Elisabeth Muetzel MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

The disruption of the collagenous fibre architecture (CFA) is considered the hallmark of irreversible damage to cartilage, which might progress to consecutive open osteoarthritis (OA). The purpose of this study was to evaluate whether DTI is able to depict the CFA of cartilage and whether DTI-based zonal heights correlate to those measured by scanning electron microscopy (SEM).

DTI data (6 directions) were acquired from 20 human patellar cartilage on bone samples at 750MHz (1500 x 62.5 × 250µm³, b: 0, 500s/mm²). ADC, fractional anisotropy (FA) and 1st eigenvector (EV) were plotted against cartilage depth from surface. SEM was performed on a Jeol35CF. Critical points of specimen preparation were the drying process (CO2), the freeze fracturing (N2), and the 400A gold sputtering. Heights of tangential (TGZ), transitional (TRZ) and radial (RZ) zones were compared between SEM and EV.

All measured DTI parameters varied with increasing depth from surface, which were consistent with the different cartilage zones. FA was 0.1 for TGZ, 0.09 for TRZ and 0.18 for RZ. Heights of TGZ, TRZ and RZ measured with DTI and SEM showed a Pearson correlation coefficient of 0.11, 0.89 and 0.87 respectively. TRZ (in SEM) exceeded TRZ (in DTI) by 20%, whereas the opposite was found for RZ.

The results showed good correlation of zonal variation and zonal height of EV compared to SEM of the CFA. Shrinkage due to preparation for SEM and partial volume effects in DTI are possible factors, which may explain the observed differences in zonal height.

DTI parameters such as ADC, FA and EV are capable of reflecting the zonal collagenous fibre architecture of cartilage suggesting high potential of DTI technique for the workup of cartilage in OA.

Glaser, C, Filidoro, L, Weber, D, Arnoldi, A, Weber, J, Reiser, M, Raya, J, Horng, A, Jakob, P, Putz, R, Muetzel, E, et al, , Collagenous Fibre Architecture of Articular Cartilage:  A Comparison between High Field DTI and Scanning Electron Microscopy.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6021197.html