Patent ID: 6238426
Filing Date: 2001-05-29
Classification: A61B,A61N,A61P

Abstract:
A method for administering light therapy to diseased tissue at an internal treatment site within a patient's body that enables the light therapy to be modified in response to a condition of the internal treatment site, comprising the steps of:(a) providing a light source that emits light within a predetermined waveband;(b) administering a photoreactive agent to the patient, said photoreactive agent having a characteristic light absorption waveband corresponding to the predetermined waveband in which light is emitted by the light source;(c) administering light to the diseased tissue with the light source over an extended perod of time;(d) ultrasonically scanning the internal treatment site at a plurality of times to produce a corresponding plurality of images, each image indicating a condition of the internal treatment site, said plurality of times including:(i) before the onset of administering the light, to produce a baseline image of the diseased tissue at the internal treatment site, prior to the internal treatment site experiencing any effect from the light subsequently administered thereto; and(ii) at least one time after an onset of administering the light; and(e) detecting changes in the condition of the internal treatment site by comparing the baseline image with a subsequent image made a substantial time after the onset of administering the light to the diseased tissue at the internal treatment site.