Preliminary study of laser welding for aortic dissection in a porcine model using a diode laser with indocyanine green

Background and Objectives The objective of this study was to determine whether a dissected aorta could be welded by a diode laser with a solder using an in vitro porcine aortic dissection model. Study Design/Materials and Methods Porcine aortic strips were dissected into two flaps and the dissected faces were immersed in a solution of indocyanine green. The two flaps were pressed at 0.2 kg/cm 2 with contact between the two immersed faces. The pressed flaps were irradiated with a diode laser (810 nm) at intensities of 170–425 W/cm 2 for 8 seconds. The welded flaps were studied by light microscopy and the adhesive strengths were measured. Results The irradiated flaps were successfully welded. The breaking stress, the maximum stress recorded in a stress‐strain curve, increased with increase in irradiation intensity up to 396 W/cm 2 (2.7 × 10 2 mmHg) and decreased when the intensity reached 425 W/cm 2 . In the specimen irradiated at 396 W/cm 2 , the welded faces showed continuous fusion of elastin layers, while some voids were seen between the welded faces in the specimen irradiated at 425 W/cm 2 . Conclusions The dissected porcine aortas were successfully welded using a laser with solder. The results suggest that the welded aorta can bear physiological blood pressure. Lasers Surg. Med. 32:341–345, 2003. © 2003 Wiley‐Liss, Inc.