Two-wavelength approach for control of coagulation depth during laser tissue soldering

Martin Wehner; Mirko Aden; Nina Toedter; Beate Rosenkranz

doi:10.1117/12.2080995

5 March 2015 Two-wavelength approach for control of coagulation depth during laser tissue soldering

Martin Wehner, Mirko Aden, Nina Toedter, Beate Rosenkranz

Proceedings Volume 9321, Optical Interactions with Tissue and Cells XXVI; 932109 (2015) https://doi.org/10.1117/12.2080995
Event: SPIE BiOS, 2015, San Francisco, California, United States

Abstract

In laser tissue soldering (LTS) protein solutions are used for closing of incisions or fixation of wound dressings. During coagulation and thermal denaturation of the protein solutions their morphology changes significantly such that light is strongly scattered. When scattering becomes major component extinction increases and the optical penetration depth shrinks which could lead to unsufficient coagulation and bonding. For adaption of extinction during coagulation we are investigating a two-wavelength approach. A strongly absorbed laser wavelength (1540 nm) and weakly absorbed wavelength (980 nm) can be applied simultaneously. Simulation of beam propagation is performed in natural and coagulated state of the solder. The model describes a three-layer system consisting of membrane, solder and phantom. The optical properties are determined by spectrometric measurements both in natural and coagulated state. The absorption coefficient μ_a, scattering coefficient μ_s and anisotropy factor γ are determined by numerical analysis from the spectrometric data. Beam propagation is simulated for 980 nm and 1540 nm radiation with ZEMAX^® software based on the Monte Carlo method. For both wavelengths the beginning of the process with a clear solder layer, and the final state characterized by a coagulated solder layer are examined. The optical penetration depth depends mainly on the optical properties of the solder, which change in the course of coagulation process. The coagulation depth can be varied between 1.5 mm to 3.5 mm by changing the proportion of both laser sources. This leads to concepts for minimizing heat input while maintaining a constant coagulation depth.

Citation Download Citation

Martin Wehner, Mirko Aden, Nina Toedter, and Beate Rosenkranz "Two-wavelength approach for control of coagulation depth during laser tissue soldering", Proc. SPIE 9321, Optical Interactions with Tissue and Cells XXVI, 932109 (5 March 2015); https://doi.org/10.1117/12.2080995

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