Diffusion Tensor Imaging and Fiber Tractography of Skeletal Muscle: Optimization of b Value for Imaging at 1.5 T

Abstract

The optimal b value for in vivo DT MRI and tractographic assessment of human skeletal muscle in the calf at 1.5 T MRI was found to be 625 s/mm(2).

Diffusion Tensor Imaging of Skeletal Muscle - Correlation of Fractional Anisotropy to Muscle Power

“…value of 600 s/mm 2 to be the optimal b-value for muscle DTI at 1.5 T. [19]. To increase the SNR (signal-tonoise ratio) the DTI sequence was repeated a total of 6 times and averaged over the further course of the analyses.…”

Gender Differences in MR Muscle Tractography

“…Several reports have discussed ways to optimize the DTI parameters of skeletal muscles to acquire better tractography or quantitative analysis data, [8][9][10] but we are aware of no report discussing how other factors might aŠect the visualization of skeletal muscle tractography. Accordingly, we started to investigate candidate muscles for tractography that could be used to clarify the underlying reasons for variation of the extent of visualized tracts among the muscles.…”

“…The 4-channel sensitivity encoding (SENSE) body coil (sized 45×30 cm for parallel imaging) was convolved around the anterior and posterior aspects of the calves bilaterally. DTI parameters were based on published literature describing DTI scans of muscle, 4,6,8,9 particularly the studies of Hatakenaka 4 and Galb áan and colleagues. 6 DiŠusion-weighted images were acquired using a single-shot, spin-echo, echo-planar imaging sequence with the parameters: b-values, 0 and 500 s/mm 2 ;ˆeld of view (FOV), 400 cm, rectangular FOV 75z; matrix size, 128×128; slice thickness, 6 mm without gap; internal number of slices, 12 (7.2 cm of the length of scan range); repetition time (TR), 2500 ms; echo time (TE), 59 ms; SENSE factor, 2; number of motion-probing gradient Before the DTI, we scanned T 1 -fastˆeld echo (FFE) images as anatomical mapping using: matrix size 256×192; slice thickness, 6 mm; internal number of slices, 12; TR, 13 ms; TE, 2.3 ms; SENSE factor 1.4; and total scan time, 3 min, 4 s.…”

“…3,5,8 DTI has great potential for diagnostic imaging and could prove useful in a variety ofˆelds, including sports medicine, orthopedics, and clinical anatomy, and aid in the diagnosis or monitoring of myogenic disorders.…”

Assessment of Postoperative Tendon Quality in Patients With Achilles Tendon Rupture Using Diffusion Tensor Imaging and Tendon Fiber Tracking

“…Ultrasonography and MRI have also been used to monitor the healing process after ATR (11), quantifying the thickness and structure of the tendon but not the quality of the repair process (10,12). Diffusion tensor imaging (DTI), which is a specialized form of MRI scanning, has been evaluated as a noninvasive technique for describing the microstructural characteristics and organization of anisotropic tissues (eg, skeletal and cardiac muscles fibers, brain, spinal cord, and kidney) by way of directionality (13)(14)(15)(16). As such, DTI and fiber tractography offer an innovative and powerful tool that might be capable of detecting microstructural abnormalities not perceivable using conventional MRI techniques (13,17).…”