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Updated: Jan 26, 2026

Measurement of Chladni Mode Shapes with an Optical Lever Method
Published on: June 5, 2020
Ultrasound-modulated optical tomography in reflection mode with ring-shaped light illumination
Chulhong Kim1, Kwang Hyun Song, Konstantin Maslov
1Washington University in St. Louis, Department of Biomedical Engineering, Optical Imaging Laboratory, Campus Box 1097, One Brookings Drive, St. Louis, Missouri 63130-4899, USA.
Abstract:
We have succeeded in implementing ring-shaped light illumination ultrasound-modulated optical tomography (UOT) in reflection mode. The system used intense acoustic bursts and a charge-coupled device (CCD) camera-based speckle contrast detection method. In addition, the implementation allows placing the tissue sample below (not within) an acoustic coupling water tank and scanning the tissue without moving the sample. Thus, the UOT system is more clinically applicable than previous transmission-mode systems. Furthermore, we have successfully imaged an ex vivo methylene-blue-dyed sentinel lymph node (SLN) embedded at a depth of 13 mm in chicken breast tissue. This UOT system offers several advantages: noninvasiveness, nonionizing radiation, portability, cost effectiveness, and the possibility of combination with ultrasound pulse-echo imaging and photoacoustic imaging. One potential application of the UOT system is mapping SLNs in axillary staging for breast cancer patients.
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