Variables in photodynamic therapy for Barrett's esophagus

Linda R. Jones; Norris W. Preyer; Jane Buchanan; Daryl M. Reynolds; Herbert C. Wolfsen; Michael B. Wallace; Kanwar R. S. Gill

doi:10.1117/12.822934

13 July 2009 Variables in photodynamic therapy for Barrett's esophagus

Linda R. Jones, Norris W. Preyer, Jane Buchanan, Daryl M. Reynolds, Herbert C. Wolfsen, Michael B. Wallace, Kanwar R. S. Gill

Author Affiliations +

Proceedings Volume 7380, Photodynamic Therapy: Back to the Future; 73800N (2009) https://doi.org/10.1117/12.822934
Event: 12th World Congress of the International Photodynamic Association, 2009, Seattle, Washington, United States

Abstract

Photodynamic therapy with porfimer sodium (PS) is a treatment option for high grade dysplasia associated with Barrett's esophagus. This study sought to investigate the optical properties of Barrett's dysplasia that may be useful in light dosimetry planning and to determine the effect of PS on tissue absorption and scattering. Fiber optic reflectance spectra were collected before and 48 hours after administration of 2 mg/kg PS. Mucosal biopsies were collected at the same locations. According to Monte Carlo analysis, the fiber optic probe sampled only the mucosal layer. A mathematical fit of the reflectance spectra was performed as a function of blood volume fraction, oxygen saturation and scattering. The average calculated blood volume was 100% higher in Barrett's tissue than normal esophageal tissue. The average scattering slope from 620 to 750 nm was 26% higher for Barrett's dysplasia than normal esophageal tissue, indicating an increase in the size of scattering particles. The difference in the scattering amplitude was not statistically significant, suggesting no significant increase in the number of scattering particles. PS tissue content was determined with extraction methods. Changes in the scattering slope due to PS sensitization were observed; however they were not proportional to the extracted PS concentration.

Citation Download Citation

Linda R. Jones, Norris W. Preyer, Jane Buchanan, Daryl M. Reynolds, Herbert C. Wolfsen, Michael B. Wallace, and Kanwar R. S. Gill "Variables in photodynamic therapy for Barrett's esophagus", Proc. SPIE 7380, Photodynamic Therapy: Back to the Future, 73800N (13 July 2009); https://doi.org/10.1117/12.822934

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