Fig. 1. Schematic of photoacoustic microscopy for injection navigation of microplastic surgery

Fig. 2. Photoacoustic microscopy navigation system.

Fig. 3. Algorithm flow chart of image fusion to count number of pixels in intersection area

Fig. 4. Photoacoustic microscopy navigation results of needle and leaf veins. (a) Three-dimensional (3D) photoacoustic images of needle and leaf veins; (b) 3D image fusion and actual situation of needle puncturing vein trunk; (c) 3D image fusion and actual situation of needle avoiding vein trunk

Fig. 5. Photoacoustic microscopy navigation results of needle and rat ear blood vessels in vivo. (a) 3D photoacoustic image of needle; (b) 3D photoacoustic image of blood vessels; (c) image fusion of needle puncturing blood vessels without transparent processing; (d) image fusion of needle puncturing blood vessels after transparent processing (inset is enlarged view of intersection area between needle and blood vessels); (e) maximum projection of blood vessels; (f) pixel number statistical map of intersection area of needle and blood vessels