Research on a Resonance Spectrum-Based Method for Measuring the Elastic Modulus of Small Size Soft Tissue Samples

The elastic properties of biological tissues are highly correlated with pathological states. Accurate measurement of tissue elasticity can offer crucial insights for early disease diagnosis and precise treatment. This study introduces a method for measuring the elastic modulus of small size soft tissue samples. We utilize a surface microbead driven by external magnetic field as the excitation source, combined with resonance spectrum measurement based on optical coherence tomography (OCT), to obtain the tissue resonance frequency under microbead excitation. This study reveals significant linear correlation (R²=0.9994) between the resonance frequency of various component phantom materials (0.5%, 0.75%, 1.0%, 1.25%, 1.5%)—respectively 118.5±3.7 Hz, 200.8±2.9 Hz, 280.0±5.2 Hz, 360.9±6.8 Hz, 431.1±6.5 Hz—and the square root of the Young's modulus. Moreover, the measured resonance frequency is unaffected by the amplitude of the magnetic excitation or the measurement location on the sample. This study provides an effective and robust way to obtain the elastic modulus of soft tissue materials.