In vivo MR tractography of thigh muscles using diffusion imaging: initial results

Abstract

The aims of this preliminary study were (1) to demonstrate the feasibility of providing in vivo 3D architecture of human thigh muscles using tractography on a 1.5T magnet, and (2) to assess the value of tractography images to obtain averaged microstructural parameters, i.e., the fractional anisotropy (FA) and the mean apparent diffusion coefficient (ADC), over the whole thigh. Five healthy volunteers were included in this study. Their right thighs were imaged using diffusion tensor imaging and gradient-echo T2* sequences. Muscular tractography was performed on each muscle. MR tractography provided a good approach of the muscle shape and of the orientation of the muscle fibers. There was no aberration in the color-encoding scheme nor in the luminosity assigned to each fiber. In contrast, tendons were not drawn in any of the muscles studied. FA values ranged from 0.27 to 0.38. Mean ADC values ranged from 0.76 to 0.96 x 10(-3) mm2/s. Our study demonstrated the feasibility of providing in vivo 3D architecture of human thigh muscles using tractography on a 1.5T magnet, and of determining muscular microstructural parameters (FA and ADC). Musculoskeletal radiologists should be aware of these new developments that may provide complementary information on muscles to the usual sequences.

Diffusion tensor imaging and fiber tractography of the median nerve at 1.5T: optimization of b value

“…There is a growing interest among researchers and radiologists in the use of MR imaging techniques such as DTI and fiber tractography for imaging the musculoskeletal system [1][2][3][4][5][6][21][22][23][24][25][26]. In our study, we acquired a series of identical single-shot spin-echo-based echo-planar imaging MR sequences in a cohort of 15 healthy volunteers in order to assess the optimal imaging parameters, i.e., the optimal b value, for DTI and fiber tractography of peripheral nerves at 1.5 T.…”

In vivo 3 T MR diffusion tensor imaging for detection of the fibre architecture of the human uterus: a feasibility and quantitative study

“…However, these limitations were overcome as the in vivo 3 T MR-DTI fibre tracking was comparable with the main fibre directions depicted in ex vivo histological analysis. There are only a select few quantitative DTI analyses carried out on in vivo human tissue such as the muscles in the thigh and the median nerve [9,16]. These studies have shown that it is possible to obtain the 3D architecture and microstructural parameters such as FA and ADC using 3 T MR-DTI.…”

“…There have been several MR-DTI feasibility studies in animals showing the anatomical fibre distribution in skeletal muscle, tongue and heart [5][6][7]. There have also been some studies on in vivo human skeletal muscle [8,9], tongue [10] and ventricular myocardium [11]. There is only one study on the uterus using MR-DTI, which was performed ex vivo on patients subjected to a hysterectomy for medical reasons [12].…”

Diffusion tensor imaging of the human calf muscle: distinct changes in fractional anisotropy and mean diffusion due to passive muscle shortening and stretching

“…Nevertheless, a multi-slice technique might be a further step towards a better understanding of muscle anatomy, physiology and pathology as several research groups have already suggested (19,33,34). It should be mentioned that perfusion could potentially influence the diffusion measurements, especially for low b-values.…”