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Infrared (IR) lasers are being tested as an alternative to conventional radiofrequency and ultrasonic surgical devices for rapid hemostatic sealing of vascular tissues. During previous studies, a reciprocating, side-firing optical fiber delivered a linear laser beam across compressed vessels, simulating pressure from laparoscopic device jaws. However, technical challenges include limited field-of-view of vessel position within the jaws, and matching the fiber scan length to variable vessel diameters (2-7 mm). Use of transparent laparoscopic jaws may improve the surgeon’s visibility and enable customized treatment. Transparent quartz square tubing (with dimensions of 2.7 x 2.7 x 25 mm, compatible with a standard 5-mm-outer-diameter laparoscopic port) was sealed on its distal end with a black resin plug for absorbing residual forward directed light. Optical transmission studies were conducted using an infrared (IR) diode laser (1470 nm / 30 W). Razor blade scans and an IR beam profiler were used to acquire side-firing fiber (550-um-core / 0.22 NA) spatial beam profiles. Thermocouples (TC) and a thermal camera recorded peak temperatures and cooling times on the inside and outside surfaces of the quartz jaw, respectively. Side-firing fibers polished at a 50° angle delivered 94% of the light radially (90°) and 2.3% in the forward (0°) direction at powers ≤ 34 W. Total reflection losses for the two quartz-air interfaces measured 6% with 94% of side-firing light transmitted through the quartz tubing wall. Peak TC temperatures on the external surface of the jaw measured 85 ± 14 °C with 23 ± 8 s to cool to body temperature (37 °C). Optical and thermal measurements were conducted on a transparent laparoscopic device jaw for IR laser sealing of vascular tissues. Further development and improved visibility may enable customization of fiber scan length to match variable compressed vessel widths during placement within device jaws.
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