High-resolution diffusivity imaging at 3.0 T for the detection of degenerative changes: a trypsin-based arthritis model.
OBJECTIVE
To establish whether it is possible to quantitatively characterize the degenerative changes in cartilage that typify arthritis on a sub-150-microm resolution scale using a 3.0 T whole body MR-scanner with a reasonable measurement time.


METHODS
This problem is addressed through diffusion-microimaging investigations on an arthritis model based on the enzymatic destruction of the proteoglycans in cartilage specimen. A 35-mm birdcage resonator made high spatial resolution possible, and diffusion-micro-imaging was achieved with the use of a strong gradient system.


RESULTS
Diffusion-weighted and quantitative parameter maps were acquired with 117 x 234 microm2 pixel resolution in less than 9 minutes. Diffusivity profiles and parameter images exhibit an increase in diffusivity in degenerated tissue.


CONCLUSIONS
In a trypsin-based arthritis model, the spatial localization and quantification of damaged areas have been shown to be possible on a whole body 3.0 T MR system. Measurement times achieved for these high spatial resolution studies make in vivo investigations feasible.
Berg
Andreas
A
Department of Medical Physics, University of Vienna, Woehringerstr, 13, A-1090 Vienna, Austria. berg@univie.ac.at
Singer
Thomas
T
Moser
Ewald
E
D000818:Animals; D001168:Arthritis / Q000473:pathology*; D002358:Cartilage, Articular / Q000473:pathology*; D002417:Cattle; D007089:Image Enhancement; D066298:In Vitro Techniques; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D013552:Swine; D014357:Trypsin / Q000494:pharmacology*
D014357:Trypsin