Fig. 1. Absorption of different components in biological tissue on different wavelengths of infrared light^[15]

Fig. 2. Basic structure of mode-locked laser and output^[19]. (a) Basic structure of mode-locked laser; (b) spectrum in frequency domain; (c) pulse sequence in time domain

Fig. 3. Mechanism of laser thrombolysis

Fig. 4. Distribution of various thermal effect regions^[28]

Fig. 5. Optical principle diagram of nitrogen assisted soft tissue laser ablation^[40]

Fig. 6. Experimental apparatus for vein laser ablation^[43]

Fig. 7. Effect of laser on thrombus^[53] (arrows indicate the minimal coagulation artifacts caused by laser-transmitted cauterization in a mixed thrombus consisting of fibrin, aggregated platelets, entrapped erythrocytes, and tubule-like aggregates of erythrocytes without signs of organization or hemosiderin depositions)

Fig. 8. Catheter and imaging^[57]. (a) Catheter distal tip, comprising mechanical blade and optical fibers; (b) intervascular ultrasound (IVUS) imaging of cadaveric superficial femoral artery (SFA) using Atlantis SR Pro2™ catheter (Boston 　Scientific), calcified lesion is shown by peripheral bright areas