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bioRxiv · 10.64898/2026.06.23.733923

In vivo real-time elastography with unmodified commercial endoscopes using noise-correlation-inspired method and laser speckle imaging

Legrand, M.·Dufour, N.·Jonca, F.·Schiffler, J.·Sosa Valencia, L.·Bahlouli, N.·Nahas, A.
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Abstract

AO_SCPLOWBSTRACTC_SCPLOWEarly tumor detection is critical for improving patient survival and recovery. Clinically, tissue palpation is routinely used to identify regions of abnormal stiffness, a hallmark of many pathological conditions. However, palpation is restricted to anatomically accessible sites and remains highly operator dependent. Here, we introduce a method for real-time quantitative stiffness mapping using an unmodified commercial endoscope, with the goal of enhancing diagnostic capabilities and restoring mechanical feedback during endoscopic procedures. Our approach combines shear wave elastography with speckle imaging and an innovative synchronization strategy that enables the measurement of shear wave propagation using an unmodified commercial endoscope. The resulting wave fields are analyzed with the noise-correlation-inspired (NCI) method[1], providing pixel-wise estimates of shear wave velocity and, consequently, quantitative maps of local tissue stiffness. The method demonstrated robust performance in both benchtop and endoscopic configurations. Validation was achieved on polymer phantoms as well as on ex vivo and in vivo biological tissues, highlighting its potential for minimally invasive biomechanical imaging and real-time tissue characterization.

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Legrand, M., Dufour, N., Jonca, F., Schiffler, J., Sosa Valencia, L., Bahlouli, N., Nahas, A.. 2026-06-29. In vivo real-time elastography with unmodified commercial endoscopes using noise-correlation-inspired method and laser speckle imaging. https://doi.org/10.64898/2026.06.23.733923

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