# Photoacoustic Microscopy for Multiscale Biological System Visualization and Clinical Translation

## TL;DR

Photoacoustic microscopy (PAM) is a non-invasive imaging technique with high resolution, reviewed for its recent advancements and potential clinical applications in precision medicine.

## Contribution

This review synthesizes recent technological innovations and clinical translation pathways for PAM, emphasizing its role in precision medicine.

## Key findings

- PAM achieves high-resolution deep-tissue imaging by using ultrasonic signals instead of purely optical methods.
- Recent advancements include high-speed scanners, AI-enhanced algorithms, and molecular agents improving PAM performance.
- PAM shows promise in applications like tumor detection, renal monitoring, and intraoperative guidance.

## Abstract

Photoacoustic microscopy (PAM) has emerged as a versatile modality in biomedical research, notable for its noninvasively, high spatial resolution, and superior optical contrast. Compared with pure optical imaging techniques, PAM leverages weakly scattered ultrasonic signals for image formation, thereby achieving high‐resolution visualization of deep tissues. This review provides a comprehensive synthesis of recent advancements in PAM, encompassing technological innovations, organ‐specific applications, and emerging pathways toward clinical translation. This discussion starts by exploring the fundamental physical principles of PAM and elaborates on the enhanced performance achieved through significant advancements in high‐speed scanners, array transducers, artificial intelligence‐enhanced algorithms, and molecular agents. Pioneering applications in single‑cell analysis, hepatic microcirculation characterization, renal clearance monitoring, tumor metastasis detection, and neuroscientific discovery are surveyed to demonstrate PAM's ability. Prospective clinical uses, including intraoperative guidance and point‑of‑care diagnostics, are considered alongside persistent limitations, notably limited penetration depth and multispectral imaging speed. Future advancements are expected to hinge on multimodal integration, deeper integration of artificial intelligence, and the development of standardized protocols to accelerate clinical implementation. Ultimately, this review offers a forward‐looking perspective aimed at accelerating the translation of PAM from a laboratory tool to a clinical mainstay in the era of precision medicine.

Photoacoustic microscopy (PAM) is a powerful biomedical imaging tool renowned for its non‐invasiveness and high resolution. This review synthesizes recent technological advances and highlights their broad applications from cellular and organ‐level to whole‐animal imaging. It further discusses the pathways and challenges for translating PAM into a clinical mainstay for precision medicine.