Suzuki Yushi, Kajita Hiroki, Oh Anna, Watanabe Shiho, Takatsume Yoshifumi, Imanishi Nobuaki, Sakuma Hisashi, Tsuji Tetsuya, Kishi Kazuo
Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, Tokyo, Japan.
Department of Anatomy, Keio University School of Medicine, Tokyo, Japan.
JPRAS Open. 2025 Mar 25;44:348-353. doi: 10.1016/j.jpra.2025.03.009. eCollection 2025 Jun.
Complex physical therapy (CPT), which combines compression and exercise therapies, is the cornerstone of lymphedema treatment. However, assessing lymphatic flow in living humans is challenging owing to the small size and transparent nature of lymphatic vessels. Herein, we introduce a novel approach utilising photoacoustic imaging (PAI) to visualise lymphatic flow dynamics under CPT conditions. Compared with existing modalities, PAI offers superior details, enabling real-time evaluation of lymphatic vessels during compression and exercise. Real-time evaluation of lymphatic flow may enable advanced research on optimal perioperative compression therapy and exercise therapy.
Herein, PAI was used to assess lymphatic flow in four healthy subjects. Detailed images of lymphatic and blood vessels were obtained using photoacoustic lymphangiography, which utilises indocyanine green as a light absorber. The participants underwent simulated compression using a transparent film dressing, with a pressure of approximately 20 mmHg. Exercise stress was applied to mimic CPT conditions. Compression facilitated the collapse of superficial veins while lymphatic vessels remained intact. Additionally, the lymphatic pumping frequency was the highest during combined compression and exercise, highlighting the synergistic effect of these therapies on lymphatic flow.
Our findings underscore the potential of PAI in elucidating the mechanisms underlying the efficacy of CPT. PAI may enable comprehensive assessments of vascular changes during CPT by allowing simultaneous delineation of veins and lymphatic vessels. While our study represents a significant step forward, its limitations, including small sample size and exercise regimen specificity, warrant further investigations.
复杂物理治疗（CPT）结合了压迫疗法和运动疗法，是淋巴水肿治疗的基石。然而，由于淋巴管尺寸小且具有透明性，在活体人类中评估淋巴流动具有挑战性。在此，我们引入一种利用光声成像（PAI）的新方法，以可视化CPT条件下的淋巴流动动力学。与现有模式相比，PAI提供了更详细的信息，能够在压迫和运动过程中对淋巴管进行实时评估。对淋巴流动的实时评估可能有助于对最佳围手术期压迫疗法和运动疗法进行深入研究。
在此，PAI被用于评估四名健康受试者的淋巴流动。使用光声淋巴管造影术获得了淋巴管和血管的详细图像，该技术利用吲哚菁绿作为光吸收剂。参与者使用透明薄膜敷料进行模拟压迫，压力约为20 mmHg。施加运动应激以模拟CPT条件。压迫促使浅静脉塌陷而淋巴管保持完整。此外，在联合压迫和运动期间淋巴泵血频率最高，突出了这些疗法对淋巴流动的协同作用。
我们的研究结果强调了PAI在阐明CPT疗效潜在机制方面的潜力。PAI通过同时描绘静脉和淋巴管，可能实现对CPT期间血管变化的全面评估。虽然我们的研究迈出了重要一步，但其局限性，包括样本量小和运动方案的特异性，仍需进一步研究。
