[Research progress of photoacoustic imaging in diagnosis of limb lymphedema].

Objective: To summarize recent advances in photoacoustic imaging (PAI) for the diagnosis of limb lymphedema. Methods: Relevant domestic and international studies on PAI were reviewed to systematically summarize its imaging principles, technological development, applications in the diagnosis of limb lymphedema, and recent advances in related technologies. Results: PAI combines the high contrast of optical imaging with the favorable tissue penetration of ultrasound. It has evolved from high-resolution microscopic imaging to large-field tomographic imaging, portable imaging, and molecularly targeted imaging, thereby establishing a technical foundation for the clinical translation of lymphatic imaging. Current studies have shown that PAI can visualize lymphatic vessels, accompanying veins, and dermal backflow, while also providing functional information to a certain extent. It therefore shows promising potential in the early diagnosis, preoperative localization, intraoperative assessment, postoperative follow-up, and staging of limb lymphedema. Furthermore, advances in related integrative and innovative technologies have further expanded the value of PAI in the diagnosis of lymphedema. Conclusion: PAI provides a promising approach for precise diagnosis and perioperative management of limb lymphedema. However, large-scale prospective studies and standardized imaging protocols are required to validate its long-term clinical value.