Mechanical Characterization of Brain Tissue: Experimental Techniques, Human Testing Considerations, and Perspectives.

Area of Science:

• Neuroscience
• Biomechanical Engineering
• Medical Physics

Background:

• Characterizing brain tissue mechanical properties is essential for neuroscience and clinical applications.
• Accurate measurement is challenging due to the brain's complex structure and mechanical attributes.

Purpose of the Study:

• To provide a comprehensive review of invasive and noninvasive techniques for brain tissue mechanical characterization.
• To guide researchers and clinicians in selecting appropriate testing methods.
• To offer a curated dataset for constitutive modeling of human brain tissue.

Main Methods:

• Review of invasive methods: atomic force microscopy, indentation, axial mechanical testing, oscillatory shear testing.
• Review of noninvasive methods: magnetic resonance elastography, ultrasound elastography.
• Systematic comparison of invasive studies: sample preparation, testing conditions, parameters, and modeling.

Main Results:

• Evaluation of techniques based on principles, applicability, studies, and limitations.
• Summary of human brain tissue mechanical property measurements from existing publications.
• Discussion of key factors influencing testing outcomes (e.g., sample size, strain rate, temperature).

Conclusions:

• Invasive and noninvasive methods offer complementary approaches for brain tissue characterization.
• Understanding influencing factors is critical for reliable mechanical property measurement.
• This review aids in selecting optimal techniques and supports constitutive modeling efforts.