Thermal strain imaging in vivo using interpolated IQ-images
Chuhao Yin1, Guanzhu Wang1, Kexin Yang1
1Key Laboratory of Modern Acoustics (MOE), School of Physics, Collaborative Innovation Centre of Advanced Microstructure, Nanjing University, Nanjing 210093, China.
Ultrasonics
|November 5, 2020
Summary
Interpolated ultrasound images can enable accurate thermal strain imaging (TSI) for thermal therapies. This method improves performance on common ultrasound machines by overcoming limitations in sampling rate and line density.
Area of Science:
- Medical Imaging
- Biomedical Engineering
- Ultrasonic Thermometry
Background:
- Thermal strain imaging (TSI) is crucial for ultrasonic thermometry in thermal therapies.
- TSI accuracy relies on B-Scan image sampling rate and line density.
- Standard IQ-demodulated ultrasound data from lower-end machines is often insufficient for TSI.
Purpose of the Study:
- To investigate the feasibility of using interpolated IQ images for TSI.
- To assess if interpolation can enhance TSI performance using low-sampling-rate data.
- To determine if common ultrasound machines can be utilized for accurate TSI.
Main Methods:
- In vivo experiments on perirenal fat in pigs.
- Application of the "infinitesimal echo strain filter" model.
- Utilizing axial and lateral interpolation techniques on IQ images, including zero-padding.
Main Results:
- Axial interpolation recovers TSI capabilities from low-sampling-rate IQ images.
- Interpolated IQ images achieve performance comparable to high-sampling-rate RF/IQ images.
- Lateral interpolation increases line density, reduces TSI errors, and enhances temperature map details.
- Thermometry coefficient (k-value) variation remained below 3%.
Conclusions:
- Interpolated IQ images make TSI feasible with common ultrasound machines.
- This approach reduces the need for high sampling rates and line densities in ultrasound imaging for TSI.
- The findings broaden the applicability of TSI in thermal therapies.
