Acoustic Microscopy for Biological Tissue Characterization

Acoustic microscopy utilises high‐frequency ultrasonic waves to probe the structural and mechanical properties of biological tissues at microscopic scales. By focusing sound beams through specialised transducers and analysing the reflected or transmitted signals, this technique can map variations in acoustic impedance, attenuation and elasticity without the need for labelling or destructive preparation. The resulting images reveal subsurface features such as collagen networks, cellular boundaries and microcalcifications, offering insights into pathological changes in cancerous lesions, vascular plaques and soft tissues. Advances in transducer technology now permit frequencies above 300 MHz, pushing spatial resolution into the submicrometre regime. Concurrently, image‐processing algorithms enhance contrast and suppress noise, enabling quantitative analysis of tissue heterogeneity, stiffness and biomechanics. These capabilities render acoustic microscopy a versatile tool for both fundamental research and potential clinical assessments, bridging gaps between histology, biomechanics and non‐invasive diagnostics.

Research from Nature Portfolio

Recent studies have refined acoustic image quality and extended applications in tissue characterisation. A novel denoising framework based on four‐dimensional block‐matching filtering was shown to outperform conventional techniques, preserving structural details in volumetric acoustic scans and raising signal‐to‐noise metrics substantially. Dual‐modality investigations combining acoustic imaging with time‐resolved fluorescence spectroscopy have demonstrated the capacity to differentiate calcified and collagen‐rich regions within atherosclerotic plaques, highlighting distinct impedance signatures and fluorescence lifetimes. Complementary work validated scanning acoustic microscopy against micro‐computed tomography, electron microscopy and elemental analysis for the delineation of microcalcifications in human carotid plaques, confirming the technique’s potential for identifying vulnerable regions through precise measurement of sound speed and acoustic impedance contrasts.

Acoustic Microscopy for Biological Tissue Characterization publication trend

The graph below shows the total number of articles in acoustic microscopy for biological tissue characterization across all publications each year (not limited to Nature Index journals).

Technical terms

Acoustic impedance: The product of tissue density and sound speed, determining the reflection and transmission of ultrasonic waves at interfaces.

Scanning acoustic microscopy (SAM): A technique that raster‐scans focused ultrasound over a sample to produce high‐resolution images of subsurface structure based on reflected signals.

Attenuation coefficient: The rate at which ultrasound amplitude diminishes per unit distance in tissue, affecting image contrast and depth penetration.

Signal‐to‐noise ratio (SNR): A measure of image quality defined by the level of desired signal relative to background noise, critical for resolving fine features.

Block‐matching and 4D (BM4D) filtering: An advanced denoising algorithm that groups similar volumetric blocks and applies collaborative filtering to suppress noise while preserving structure.

References

1. Image denoising in acoustic microscopy using block-matching and 4D filter. Scientific Reports (2023).
2. Scanning Acoustic Microscopy and Time-Resolved Fluorescence Spectroscopy for Characterization of Atherosclerotic Plaques. Scientific Reports (2018).
3. Determination of Ultrastructural Properties of Human Carotid Atherosclerotic Plaques by Scanning Acoustic Microscopy, Micro-Computer Tomography, Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy. Scientific Reports (2019).
4. High-resolution imaging in acoustic microscopy using deep learning. Machine Learning: Science and Technology (2024).
5. Novel Water Probe for High-Frequency Focused Transducer Applied to Scanning Acoustic Microscopy System: Simulation and Experimental Investigation. Sensors (2024).
6. Uncertainty analysis of Altantic salmon fish scale’s acoustic impedance using 30 MHz C-Scan measurements. Ultrasonics (2024).