Fractionated PDT light delivery system based on fiber optic switching technology

Dwayne J. Dickey; Zengyen Xiao; Kevin J Partridge; Ronald B Moore; John Tulip

doi:10.1117/12.499868

16 October 2003 Fractionated PDT light delivery system based on fiber optic switching technology

Dwayne J. Dickey, Zengyen Xiao, Kevin J Partridge, Ronald B Moore, John Tulip

Proceedings Volume 5142, Therapeutic Laser Applications and Laser-Tissue Interactions; (2003) https://doi.org/10.1117/12.499868
Event: European Conferences on Biomedical Optics 2003, 2003, Munich, Germany

Abstract

Photodynamic Therapy, PDT, promises to be an effective and minimally invasive modality for the treatment of this early stage disease. Typically PDT of solid tumours is performed using an array of interstitial fibreoptic light sources implanted in the tumour, illuminated continuously with light from a single laser until the required lethal dose of light is delivered. The literature teaches that PDT is dose rate independent so that the illumination intensity of the sources will not influence the therapeutic outcome. Recent work, however, suggests that this teaching should be qualified. PDT will saturate when the cellular oxygen is depleted, consumed by the photo-oxidation of the photosensitizer. This implies that time fractionated light delivery should increase the lethality of treatment. In this paper we describe a computer controlled time fractionated fibre optic light delivery/detection system that may be used to synchronize treatment and tissue perfusion. Two laser diodes are each coupled to a computer controlled fibreoptic switch. The switch couples the laser sequentially to an array of interstitial fibre optic light sources. The dose delivered to each source is time moderated so that a non-uniform dose distribution may be delivered across the tumour. We describe preliminary results of this light delivery system and the photo-toxin QLT0074 for the treatment of rats with AT an -H flank tumours. We also compare tissue response to both time-fractionated and continuous light delivery.

Citation Download Citation

Dwayne J. Dickey, Zengyen Xiao, Kevin J Partridge, Ronald B Moore, and John Tulip "Fractionated PDT light delivery system based on fiber optic switching technology", Proc. SPIE 5142, Therapeutic Laser Applications and Laser-Tissue Interactions, (16 October 2003); https://doi.org/10.1117/12.499868

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