Simultaneous sealing and bisection of porcine renal blood vessels, ex vivo, using a continuous-wave, infrared diode laser at 1470 nm

Abstract

Electrosurgical and ultrasonic devices are used in surgical procedures for hemostatic sealing and bisection of vascular tissues. Previous benchtop studies alternatively demonstrated successful infrared laser sealing and cutting of blood vessels, in a sequential, two-step approach. This study describes a smaller, laparoscopic device compatible design, and simultaneous approach to sealing and bisection of vessels, with potential optical feedback. A 1470-nm infrared diode laser sealed and bisected 40 porcine renal arteries, ex vivo. A reciprocating, side-firing, optical fiber, housed in a transparent square quartz optical chamber (2.7 × 2.7 × 25 mm outer dimensions), delivered laser energy over an 11 mm scan length, with a range of incident powers (41–59 W) and treatment times (5–21 s). Vessel diameters ranged from 2.5 to 4.8 mm. Vessel burst pressure measurements were performed on each cut end (n = 80) with success indicated by pressures exceeding 360 mmHg. All vessel ends were successfully sealed and bisected (80/80). The highest incident power, 59 W, yielded short treatment times of 5–6 s. Peak temperatures on the external chamber surface reached 103 oC. Time to cool down to body temperature measured 37 s. Infrared lasers simultaneously seal and bisect blood vessels, with treatment times comparable to, and temperatures and cooling times lower than reported for conventional devices. Future work will focus on integrating the fiber and chamber into a standard 5-mm-outer-diameter laparoscopic device. Customization of fiber scan length to match vessel size may also reduce laser energy deposition, enabling lower peak temperatures, treatment times, and cooling times.