Laser spot size and beam profile studies for tissue welding applications

Nathaniel M. Fried; Vincent C. Hung; Joseph T. Walsh Jr.

doi:10.1117/12.350952

22 June 1999 Laser spot size and beam profile studies for tissue welding applications

Nathaniel M. Fried, Vincent C. Hung, Joseph T. Walsh Jr.

Proceedings Volume 3590, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems IX; (1999) https://doi.org/10.1117/12.350952
Event: BiOS '99 International Biomedical Optics Symposium, 1999, San Jose, CA, United States

Abstract

We evaluated the effect of changes in laser spot size and beam profile on the thermal denaturation zone produced during laser skin welding. Our objective was to limit heating of the tissue surface, while creating enough thermal denaturation in the deeper layers of the dermis to produce full-thickness welds. Two-cm-long, full-thickness incisions were made on the backs of guinea pigs, in vivo. India ink was used as an absorber. Continuous-wave, 1.06-μm, Nd:YAG laser radiation was scanned over the incisions, producing approximately 100 ms pulses. Cooling times of 10.0 s between scans were used. Laser spot diameters of 1, 2, 4, and 6 mm were studied, with powers of 1, 4, 16, and 36 W, respectively. The irradiance remained constant at 127 W/cm². 1, 2, and 4 mm diameter spots produced thermal denaturation to a depth of 570 ± 100 μm, 970 ± 210 μm, and 1470 ± 190 μm, respectively. The 6-mm- diameter spot produced full-thickness welds (1900 μm), but also burns due to the high incident power. Monte Carlo simulations were also conducted, varying the laser spot diameter and beam profile. The simulations verified that an increase in laser spot diameter result in an increase in the penetration depth of radiation into the tissue.

Citation Download Citation

Nathaniel M. Fried, Vincent C. Hung, and Joseph T. Walsh Jr. "Laser spot size and beam profile studies for tissue welding applications", Proc. SPIE 3590, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems IX, (22 June 1999); https://doi.org/10.1117/12.350952

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available