dGEMRIC (Delayed Gadolinium-Enhanced MRI of Cartilage) Indicates Adaptive Capacity of Human Knee Cartilage

Magn Reson Med. 2004 Feb;51(2):286-90. doi: 10.1002/mrm.10714.

Abstract

Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is a new imaging technique to estimate joint cartilage glycosaminoglycan content by T1-relaxation time measurements after penetration of the hydrophilic contrast agent Gd-DTPA(2-). This study compares dGEMRIC in age-matched healthy volunteers with different levels of physical activity: Group 1 (n = 12): nonexercising individuals; Group 2 (n = 16): individuals with physical exercise averaging twice weekly; Group 3 (n = 9): male elite runners. dGEMRIC was performed 2 hr after an intravenous injection of Gd-DTPA(2-) at 0.3 mmol/kg body weight. T1 differed significantly between the three different levels of physical exercise. T1 values (mean of medial and lateral femoral cartilage) for Groups 1, 2, and 3 were: 382 +/- 33, 424 +/- 22 and 476 +/- 36, respectively (ms, mean +/- SD) (P = 0.0004, 1 vs. 2 and 0.0002, 2 vs. 3). Irrespective of the exercise level, T1 was longer in lateral compared to medial femoral cartilage (P = 0.00005; n = 37). In conclusion, this cross-sectional study indicates that human knee cartilage adapts to exercise by increasing the glycosaminoglycan content. Furthermore, results suggest a compartmental difference within the knee with a higher glycosaminoglycan content in lateral compared to medial femoral cartilage. A higher proportion of extracellular water, i.e., larger distribution volume, may to some extent explain the high T1 in the elite runners.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomechanical Phenomena
  • Cartilage, Articular / metabolism
  • Cartilage, Articular / physiology*
  • Contrast Media
  • Exercise / physiology*
  • Female
  • Gadolinium DTPA
  • Glycosaminoglycans / metabolism
  • Humans
  • Knee Joint / physiology*
  • Magnetic Resonance Imaging / methods*
  • Male

Substances

  • Contrast Media
  • Glycosaminoglycans
  • Gadolinium DTPA