Optical coherence elastography measures elasticity—a property correlated with pathologies such as tumors due to fibrosis, atherosclerosis due to heterogeneous plaque composition, and ocular diseases such as keratoconus and glaucoma. Wave-based elastography, including reverberant elastography, leverages the properties of shear waves traveling through tissue primarily to infer shear modulus. These methods have already seen significant development over the past decade. However, existing implementations in OCT require robust synchronization of shear wave excitation with imaging, complicating widespread clinical adoption. We present a method for complete recovery of the harmonic shear wave field in an asynchronous, conventional frame-rate, raster-scanning OCT system by modeling raster-scanning as an amplitude modulation of the displacement field. This technique recovers the entire spatially and temporally coherent complex-valued shear wave field from just two B-scans, while reducing the time scale for sensitivity to motion from minutes to tens of milliseconds. To the best of our knowledge, this work represents the first successful demonstration of reverberant elastography on a human subject
This content will become publicly available on May 21, 2025
Given its real-time capability to quantify mechanical tissue properties, ultrasound shear wave elastography holds significant promise in clinical musculoskeletal imaging. However, existing shear wave elastography methods fall short in enabling full-limb analysis of 3D anatomical structures under diverse loading conditions, and may introduce measurement bias due to sonographer-applied force on the transducer. These limitations pose numerous challenges, particularly for 3D computational biomechanical tissue modeling in areas like prosthetic socket design. In this feasibility study, a clinical linear ultrasound transducer system with integrated shear wave elastography capabilities was utilized to scan both a calibrated phantom and human limbs in a water tank imaging setup. By conducting 2D and 3D scans under varying compressive loads, this study demonstrates the feasibility of volumetric ultrasound shear wave elastography of human limbs. Our preliminary results showcase a potential method for evaluating 3D spatially varying tissue properties, offering future extensions to computational biomechanical modeling of tissue for various clinical scenarios.
more » « less- PAR ID:
- 10508600
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Ultrasonic Imaging
- Volume:
- 46
- Issue:
- 4-5
- ISSN:
- 0161-7346
- Format(s):
- Medium: X Size: p. 251-262
- Size(s):
- p. 251-262
- Sponsoring Org:
- National Science Foundation
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in vivo with a conventional frame-rate, raster-scanning OCT system, greatly expanding opportunity for widespread translation. -
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