Selective tumor destruction with photodynamic therapy: exploitation of photodynamic thresholds

Hugh Barr M.D.

doi:10.1117/12.48201

1 November 1991 Selective tumor destruction with photodynamic therapy: exploitation of photodynamic thresholds

Hugh Barr M.D.

Proceedings Volume 1525, Future Trends in Biomedical Applications of Lasers; (1991) https://doi.org/10.1117/12.48201
Event: MedTech '91, 1991, Berlin, Germany

Abstract

The uptake and distribution of the photosensitizer aluminum sulphonated phthalocyanine (AlSPc) has been studied. In a variety of experimentally induced gastrointestinal tumors the photosensitizer is retained between 24 - 48 hours after intravenous administration compared with the adjacent normal tissue in which the tumor arose. However, the maximum tumor-to- normal-tissue ratio was only 2:1. Quantitative fluorescence photometry using digital image processing, with a CCD camera and helium neon laser, was used to probe the microscopic localization of the photosensitizer in tissue sections of tumor and normal tissue. Selective localization of the photosensitizer was nonspecific in tumor stroma and there was never any significant difference between normal and neoplastic cells. Exploitation of the small differences in photosensitizer concentration, photodynamic threshold effects, and photosensitizer photodegration allows up to 2 mm of selective tumor damage to be produced in a tumor, when a similar light dose will produce no damage in adjacent normal tissue. However, selective eradication of a tumor without adjacent tissue damage will not be possible by using these methods. This paper reviews this previously reported data.

Citation Download Citation

Hugh Barr M.D. "Selective tumor destruction with photodynamic therapy: exploitation of photodynamic thresholds", Proc. SPIE 1525, Future Trends in Biomedical Applications of Lasers, (1 November 1991); https://doi.org/10.1117/12.48201

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