Diffusion and near-equilibrium distribution of MRI and CT contrast agents in articular cartilage

  • Silvast T
  • Kokkonen H
  • Jurvelin J
 et al. 
  • 56

    Readers

    Mendeley users who have this article in their library.
  • 43

    Citations

    Citations of this article.

Abstract

Charged contrast agents have been used both in vitro and in vivo for estimation of the fixed charge density (FCD) in articular cartilage. In the present study, the effects of molecular size and charge on the diffusion and equilibrium distribution of several magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents were investigated. Full thickness cartilage disks (Ø = 4.0 mm, n = 64) were prepared from fresh bovine patellae. Contrast agent (gadopentetate: Magnevist((R)), gadodiamide: Omniscan, ioxaglate: Hexabrix or sodium iodide: NaI) diffusion was allowed either through the articular surface or through the deep cartilage. CT imaging of the samples was conducted before contrast agent administration and after 1, 5, 9, 16, 25 and 29 h (and with three samples after 2, 3, 4 and 5 days) diffusion using a clinical peripheral quantitative computed tomography (pQCT) instrument. With all contrast agents, the diffusion through the deep cartilage was slower when compared to the diffusion through the articular surface. With ioxaglate, gadopentetate and gadodiamide it took over 29 h for diffusion to reach the near-equilibrium state. The slow diffusion of the contrast agents raise concerns regarding the validity of techniques for FCD estimation, as these contrast agents may not reach the equilibrium state that is assumed. However, since cartilage composition, i.e. deep versus superficial, had a significant effect on diffusion, imaging of the nonequilibrium diffusion process might enable more accurate assessment of cartilage integrity.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text

Authors

  • Tuomo S. Silvast

  • Harri T. Kokkonen

  • Jukka S. Jurvelin

  • Thomas M. Quinn

  • Miika T. Nieminen

  • Juha Töyräs

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free