Comparison of 2D fiber network orientation measurement methods

Area of Science:

• Biomaterials Science
• Materials Engineering
• Image Analysis

Background:

• Mechanical properties of tissues and biomaterials depend on microstructure.
• Characterizing fiber architecture is crucial for mechanical modeling but remains challenging.
• Existing image-based methods (MIL, LFD, FTM) lack comparative performance data for fiber networks.

Purpose of the Study:

• To compare the accuracy and efficiency of image-based methods for characterizing fiber architecture.
• To evaluate Mean Intercept Length (MIL), Line Fraction Deviation (LFD), and Fourier Transform Methods (FTM) on simulated fiber networks.

Main Methods:

• Constructed 40 2D simulated fiber networks with varying parameters (fiber number, orientation, anisotropy).
• Assessed accuracy of MIL, LFD, and FTM in measuring principal direction (theta) and anisotropy index (alpha).
• Compared execution time and reliability of each method.

Main Results:

• Fourier Transform Methods (FTM) demonstrated superior accuracy (Deltatheta = 2.95° ± 6.72°, Deltaalpha = 0.03 ± 0.02) and speed.
• Mean Intercept Length (MIL) showed comparable accuracy (Deltatheta = 6.23° ± 10.68°, Deltaalpha = 0.08 ± 0.06) but was significantly slower.
• Line Fraction Deviation (LFD) consistently underperformed (Deltatheta = 9.97° ± 11.82°, Deltaalpha = 0.24 ± 0.13).

Conclusions:

• FTM is the most reliable and efficient method for quantifying fiber architecture in microstructural images.
• FTM's qualitative agreement with SEM micrographs of fibrin gels suggests its applicability to real biological samples.
• FTM provides a robust tool for image-based statistical measurements of complex microstructures.