Mechanism of aneurysm formation after 830-nm diode-laser-assisted microarterial anastomosis.

Objective: The process of aneurysm formation after laser welding is described.
Summary Background Data: The mechanism of aneurysm formation after laser-assisted microarterial anastomosis is presently unclear.
Methods: A series of 830-nm diode-laser-assisted longitudinal aortorrhophy with a condition of 400 to 500 J/mm2 for 1 cm length of anastomosis versus conventional manual anastomoses were performed in 90 Wistar rats. To compare this technique with normal media process, a histologic examination of aneurysm formation was conducted.
Results and Conclusions: The results show that there are two important factors that cause aneurysm formation after laser-assisted anastomosis: 1) the vessel wall is damaged by laser heating; 2) proliferation of collagen fiber at the adventitia is absent during media reconstruction.