Miniaturized Fiber-End Probe for Laser Speckle Rheology of Atherosclerotic Plaque

Atherosclerosis is a primary cause of cardiovascular disease, with plaque viscoelasticity reflecting mechanical properties related to stability and acute event risk. However, existing viscoelastic measurement devices struggle to meet intravascular miniaturization needs. To address this limitation, we designed a fiber-end rheology (FER) probe structure based on total internal reflection and fabricated it using femtosecond laser two-photon polymerization. Combined with laser speckle rheology (LSR), it measured viscoelastic moduli of liquids and biological tissues, showing high consistency with rheometer results in the midfrequency range (r > 0.95). A deep learning model corrected light scattering interference, achieving MAE < 0.25% and MSE < 0.01% in modulus prediction. Rat carotid artery experiments, combined with histopathological analysis, validated LSR's potential for early atherosclerosis diagnosis.