Photodynamic therapy (PDT) of tumors in the urinary bladder requires a homogeneous light distribution on the whole organ wall. The light applicator recently developed consists of a catheter-supported isotropic emitter and a concentric outer balloon, which guarantees a centric position. For dosimetry a detector fiber with conical end is axially placed half way between center and bladder outlet. It detects the light backscattered from the bladder wall. It has been tested by means of a bladder phantom model with variable backscattering properties. To study the limits of this irradiation and dosimetry concept in case of nonspherical bladder shapes the light distributions in hollow ellipsoids with backscattering surface have been investigated by computer simulation. It shows that the ratio of the largest to the smallest fluence rate and the ratio of the largest to the smallest diameter of the bladder are nearly equal.

Date Published: 1 March 1994
PDF: 5 pages
Proc. SPIE 2078, Photodynamic Therapy of Cancer, (1 March 1994); doi: 10.1117/12.168714

Published in SPIE Proceedings Vol. 2078:
Photodynamic Therapy of Cancer
Giulio Jori; Johan Moan; Willem M. Star, Editor(s)