Photoacoustic microscopy: a novel approach for studying perforator skin flap in a mouse model.

Background A comprehensive understanding of cutaneous microvessels is key to the design and use of the perforator skin flap. Compared with the various imaging technologies that have been applied in the clinical practice of the perforator skin flap, photoacoustic microscopy (PAM) is a very promising noninvasive imaging modality with high resolution and deep penetration in biological tissues. Methods PAM was employed to explore its multiple applications in a perforator skin flap. The following experiments were then conducted in 3 parts. In part 1, 7 mice were used to obtain the preoperative perforator mapping on the mouse back. In parts 2 and 3, 7 mice were used to design and harvest the multiterritory perforator flap. The status of the flap and the morphological changes of choke vessels were subsequently observed by PAM at several time points. Results The results showed that PAM could visualize and assess the vascular physiological and pathological conditions of the skin tissue in real time in vivo with high spatial and temporal resolution. It could also provide preoperative perforator mapping, including the total number of perforators, localization, vascular territories, and diameter. Furthermore, it could offer a quantitative, objective method to monitor the status of the perforator skin flap, and was capable of noninvasive characterization of the changes of choke vessels that play an important role in multiterritory perforator skin flap expansion and survival. Conclusions PAM has great potential to be an effective and precise quantitative imaging tool for perforator skin flap research, such in as flap design, monitoring, and choke vessel observation.