Aging effects on human calf muscle properties assessed by MRI at 3 Tesla

Nina F. Schwenzer, Petros Martirosian, Jürgen Machann, Christina Schraml, Günter Steidle, Claus D. Claussen and Fritz Schick
Journal of Magnetic Resonance Imaging 2008, 29, 1346-1354

The purposes of this study was to determine age-related changes in MR properties as T2 and T2* relaxation times, fat content, and magnetization transfer in the human calf, and comparison of these effects in different muscle groups.
Studies were performed on 12 younger (mean, 31.2 ± 6.1 years) and 11 older healthy adult individuals (mean, 66.1 ± 7.8 years). The tibialis anterior muscle, the soleus muscle and the gastrocnemius muscle were examined at rest in a 3 Tesla whole-body MR unit. T2 and T2*, muscular fat content and magnetization transfer ratios (MTR) were determined. Results of the two age groups were compared, and differences between the muscle groups were investigated.
Increase of T2 and muscular fat was detected with age with significant difference between the age groups. The extent of fatty infiltration was much more variable for the older group. For both age groups, the tibialis anterior muscle showed the lowest fat content with 1.2 ± 0.4% in the young group and 2.3 ± 0.7% in the older group. A strong correlation between fat content and T2 was found, while the groups did not significantly differ regarding T2*. Decrease in the MTR could only be shown for the tibialis anterior muscle with age.
Age-related changes in healthy human calf musculature were found. Further studies might show possible correlations of age-dependent changes with physical efficiency and susceptibility to diseases like type 2 diabetes.