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Suture ligation with subsequent cutting of blood vessels to maintain hemostasis during surgery is time consuming
and skill intensive. Energy-based, electrosurgical and ultrasonic devices are often used to replace sutures and
mechanical clips to provide rapid hemostasis, and decrease surgical time. Some of these devices may create
undesirably large collateral zones of thermal damage and tissue necrosis, or require separate mechanical blades for
cutting. Infrared lasers are currently being explored as alternative energy sources for vessel sealing applications. In
a previous study, a 1470-nm laser was used to seal vessels of 1-6 mm in diameter in 5 s, yielding burst pressures of
~ 500 mmHg. The purpose of this study was to provide faster sealing, incorporate transection of the sealed vessels,
and increase the burst pressure. A 110-Watt, 1470-nm laser beam was transmitted through a fiber and beam shaping
optics, producing a linear beam 3.0 mm by 9.5 mm for sealing, and 1.1 mm by 9.6 mm for cutting (FWHM). A twostep
process sealed then transected ex vivo porcine renal vessels (1-8.5 mm diameter) in a bench top setup. Seal and
cut times were 1.0 s each. A standard burst pressure system measured resulting seal strength, and gross and
histologic thermal damage measurements were also recorded. All blood vessels tested (n = 30) were sealed and cut,
with total irradiation times of 2.0 s, mean burst pressures > 1000 mmHg (compared to normal systolic blood
pressure of 120 mmHg), and combined seal/collateral thermal coagulation zones of 2-3 mm. The results of this
study demonstrated that an optical-based system is capable of precisely sealing and cutting a wide range of porcine
renal vessel sizes, and with further development, may provide an alternative to radiofrequency and ultrasound-based
vessel sealing devices.
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