Ex vivo efficacy demonstration of a laser fenestration system for endovascular abdominal aortic aneurysm repair (EVAR)

Laser-generated fenestration is an alternative option for the intraoperative and selective modification of a endovascular endograft, especially in cases where patients are unsuitable for a standard endovascular aneurysms repair. Recently, diode laser approach has been proposed as a substitution of mechanical fenestration. In fact, using a near infrared wavelength (810 nm), the stent graft fabric can be successfully perforated. In this work we report an ex-vivo study providing the harmlessness of laser irradiation effects on biological tissue surrounding the endograft wall. 225 samples of human aortic tissue were irradiated varying energy and pulse duration of an 810 nm diode laser. Irradiated tissues were analyzed under histological examination. Thermal damage was evidenced in the 7.5% of the irradiated samples, typically in the contact area between the laser fiber tip and the aortic wall. These experiments suggest that the diode laser can be safely used for the proposed surgical application.