Wavelength-dependent scattering of light during Nd:YAG laser heating of porcine septal cartilage

Reshmi Basu; Brian Jet-Fei Wong M.D.; Steen J. Madsen

doi:10.1117/12.434728

9 July 2001 Wavelength-dependent scattering of light during Nd:YAG laser heating of porcine septal cartilage

Reshmi Basu, Brian Jet-Fei Wong M.D., Steen J. Madsen

Proceedings Volume 4257, Laser-Tissue Interaction XII: Photochemical, Photothermal, and Photomechanical; (2001) https://doi.org/10.1117/12.434728
Event: BiOS 2001 The International Symposium on Biomedical Optics, 2001, San Jose, CA, United States

Abstract

Heat alters the bulk physical properties of cartilage tissue, including the optical scattering and absorption coefficients. The purpose of this investigation was to measure wavelength dependent scattering of light using three different probe lasers (λ= 488 nm, 670 nm, 808 nm) during Nd:YAG laser (λ= 1.32 micrometers , 50 Hz pulse repetition rate) heating of porcine septal cartilage. An integrating sphere was used to collect diffusely backscattered light from these probe lasers and three lock- in amplifiers were used to discriminate between the different signals. Peak signal intensity of the backscattered light was observed at different temperature depending on the probe laser wavelength and specimen thickness. The observed changes are unlikely due to axial thermal gradients created during Nd:YAG laser heating and do not correlate with the fluence distribution of the three probe laser wavelengths evaluated. The observed wavelength dependent differences suggest that tissue matrix alterations during heating are due to macromolecular conformation changes that occur on the scale of the wavelength of the probe laser light. As changes in the bulk properties of cartilage can be inferred by using simple non-contact techniques such as light scattering, the characterization of the wavelength dependence of these phenomena will become increasingly important.

Citation Download Citation

Reshmi Basu, Brian Jet-Fei Wong M.D., and Steen J. Madsen "Wavelength-dependent scattering of light during Nd:YAG laser heating of porcine septal cartilage", Proc. SPIE 4257, Laser-Tissue Interaction XII: Photochemical, Photothermal, and Photomechanical, (9 July 2001); https://doi.org/10.1117/12.434728

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