[Diffusion-weighted MR tomography: navigated multi-shot SE-EPI technique for clinical use]

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Diffusion Weighted Imaging (DWI)

Background:

• Conventional spin-echo (SE) and single-shot SE echo-planar imaging (EPI) sequences have limitations in routine clinical MR diffusion imaging.
• Susceptibility artifacts and motion artifacts can affect image quality and reproducibility.

Purpose of the Study:

• To evaluate a navigated multi-shot SE EPI sequence for routine clinical use in MR diffusion imaging.
• To compare its performance against conventional SE and single-shot SE EPI sequences.

Main Methods:

• A navigated multi-shot SE EPI sequence was compared with conventional SE and single-shot SE EPI sequences on a 1.5 Tesla MR scanner.
• Image quality and apparent diffusion coefficient (ADC) reproducibility were assessed using phantoms and healthy volunteers.
• ADC values in different brain areas were determined in 20 volunteers.

Main Results:

• The multi-shot SE EPI sequence demonstrated significantly shorter measurement times and reduced motion artifacts compared to the SE sequence.
• It exhibited fewer susceptibility artifacts than the single-shot SE EPI sequence.
• The reproducibility of diffusion coefficients was found to be better than 10%.

Conclusions:

• The navigated multi-shot SE EPI technique is more practical and clinically meaningful than conventional SE and single-shot SE EPI methods on standard 1.5T scanners.
• This technique is recommended as the preferred method for diffusion imaging in clinical settings.
• It provides reliable determination of diffusion coefficients and characteristic tissue values.