Sutureless microvascular anastomoses by a biodegradable laser-activated solid protein solder

A new sutureless technique to successfully anastomose the abdominal aorta o f rats (1.3 mm in diameter) by using a fully biodegradable, laser-activated protein solder is pre presented. A total of 90 rats were divided into two groups randomly. In group one, the anastomoses were performed by using conv entional microsuturing technique, whereas in group two, the anastomoses wer e performed by using a new laser welding technique. In addition, each of th e two groups were divided into five subgroups and evaluated at different fo llow-up periods (10 minutes, I hour, 1 dq, I week, and 6 weeks). At these i ntervals, the anastomoses were evaluated for patency and tensile strength. Three anastomoses in each subgroup were processed for light and electron mi croscopy. All anastomoses were found to be patent. The mean clamp time of t he anastomoses performed with conventional suturing was 20.6 minutes compar ed with 7.2 minutes for the laser-activated welded anastomoses (p < 0.001). The strain measurements showed a stronger mechanical bond of the sutured a nastomoses in the initial phase. However, at 6 weeks the tensile strength o f the laser-welded anastomoses was higher compared dth the conventional sut ure technique. Histologic evaluations revealed a near complete resorption o f the solder after 6 weeks. The junction site of the vessel ends cannot be determined on the luminal side of the artery. In conclusion, a resorbable p rotein used as a solder, activated by a diode laser, can provide a reliable , safe, and rapid arterial anastomosis, which could be performed by any mic rosurgeon faster than conventional suturing after a short learning curve.