Dependence of Magnetic Resonance Elastography-Derived Stiffness Values on Selected Imaging Parameters

Area of Science:

• Medical Imaging
• Hepatology
• Biophysics

Background:

• Liver stiffness measurement is vital for diagnosing and monitoring liver diseases.
• Magnetic Resonance Elastography (MRE) is a non-invasive technique to assess liver stiffness.
• Optimizing MRE acquisition parameters is essential for reliable results.

Purpose of the Study:

• To investigate the impact of driver power and slice thickness on MRE-derived liver stiffness.
• To evaluate these effects in both human subjects and a tissue-mimicking phantom.
• To determine the need for standardization of MRE parameters.

Main Methods:

• A prospective observational study involving 34 adult participants and a phantom.
• MRE was performed on a 1.5T scanner using a 2D gradient-recalled echo-based sequence.
• Varied driver powers (10%-100%) and slice thicknesses (2-10 mm) were tested; two ROI approaches were used.

Main Results:

• Driver power significantly influenced individual slice stiffness measurements (p < 0.001 to 0.031) and whole-liver stiffness (p = 0.037).
• Slice thickness significantly affected individual slice measurements (p = 0.007) but not whole-liver stiffness.
• Phantom studies showed significant influence of both parameters (p < 0.001 to 0.017); repeatability was good to excellent in vivo (0.79-0.96).

Conclusions:

• MRE-derived liver stiffness is sensitive to driver power and slice thickness.
• Standardization of these acquisition parameters is necessary for consistent clinical and research applications.
• Further research should focus on establishing standardized MRE protocols.