Quantitative Analysis of Tissue Structure and Function by Scanning Acoustic Microscopy and Its Multifaceted Applications in Pathological Diagnosis

Scanning acoustic microscopy (SAM) is emerging as a powerful modality for analyzing tissue structure and function, offering unique advantages over traditional optical microscopy. Unlike optical imaging, which requires time-consuming, costly staining procedures and is limited to morphological evaluation, SAM provides high-resolution, quantitative images without staining and enables assessment of functional properties such as stiffness and viscosity. Using high-frequency ultrasound, SAM generates detailed acoustic histological images based on the speed of sound and sound attenuation, enabling rapid, repeatable measurements within the same tissue section. This review outlines the principles of SAM, including sample preparation, measurement of acoustic properties, and image acquisition. Practical advantages, such as the ability to observe chronological changes in tissue, evaluate responses to chemical or physical modifications, and track disease progression, are highlighted. Biomedical applications are discussed with an emphasis on pathological diagnosis, including cancer and degenerative diseases, as well as studies on tissue aging, drug effects, and enzymatic modifications. SAM has demonstrated its capability to distinguish tissue types, follow pathological alterations, and provide quantitative data for statistical analysis. The technology enables real-time monitoring of changes in the cellular and extracellular matrix, glycation, proteolysis, and DNA degradation. Furthermore, the use of specific antibodies allows selective preservation of target antigens during enzymatic digestion, expanding diagnostic and research possibilities. While SAM requires flat, well-prepared sections and specialized equipment, its ability to deliver both morphological and functional insights makes it a valuable complement to optical microscopy. Integrating SAM into research and clinical practice holds promise for advancing pathological diagnosis, evaluating therapeutic efficacy, and enhancing our understanding of dynamic tissue responses. In summary, SAM provides a versatile, non-staining, and quantitative approach to tissue analysis, bridging the gap between structure and function in biomedical science.