We are exploring infrared (IR) lasers as an alternative energy modality to radiofrequency (RF) and ultrasonic (US) devices intended to provide rapid surgical hemostasis with minimal collateral zones of thermal damage and tissue necrosis. Previously, a 1470-nm IR laser sealed and cut ex vivo porcine renal arteries of 1-8 mm in 2 s, yielding burst pressures < 1200 mmHg (compared to normal systolic blood pressure of 120 mmHg) and thermal coagulation zones < 3 mm (including the seal). This preliminary study describes in vivo testing of a laser probe in a porcine model. A prototype, fiber optic based handheld probe with vessel/tissue clasping mechanism was tested on blood vessels < 6 mm diameter using incident 1470-nm laser power of 35 W for 1-5 s. The probe was evaluated for hemostasis after sealing isolated and bundled vasculature of abdomen and hind leg, as well as liver and lung parenchyma. Sealed vessel samples were collected for histological analysis of lateral thermal damage. Hemostasis was achieved in 57 of 73 seals (78%). The probe consistently sealed vasculature in small bowel mesentery, mesometrium, and gastro splenic and epiploic regions. Seal performance was less consistent on hind leg vasculature including saphenous arteries and bundles and femoral and iliac arteries. Collagen denaturation averaged 1.6 mm in 8 samples excised for histologic examination. A handheld laser probe sealed porcine vessels in vivo. With further improvements in probe design and laser parameter optimization, IR lasers may provide an alternative to RF and US vessel sealing devices.

Date Published: 26 February 2015
PDF: 7 pages
Proc. SPIE 9303, Photonic Therapeutics and Diagnostics XI, 930319 (26 February 2015); doi: 10.1117/12.2076211

Published in SPIE Proceedings Vol. 9303:
Photonic Therapeutics and Diagnostics XI
Hyun Wook Kang; Brian J. F. Wong M.D.; Melissa C. Skala; Bernard Choi; Guillermo J. Tearney M.D.; Andreas Mandelis; Nikiforos Kollias; Kenton W. Gregory M.D.; Mark W. Dewhirst D.V.M.; Justus F. Ilgner M.D.; Alfred Nuttal; Haishan Zeng; Laura Marcu; Claus-Peter Richter, Editor(s)