Photodynamic therapy apparatus and method for vascular tissue treatment

A method for using photodynamic therapy to treat vascular tissue, comprising the steps of:

• (a) providing a vascular illumination apparatus comprising:
• (i) an elongate, flexible body having a proximal end and a distal end;
• (ii) at least one forward facing light source disposed adjacent to the distal end of the elongate, flexible body, the at least one forward facing light source, when energized, emitting light having a characteristic emission waveband;
• (iii) a diffusing distal tip;
• and
• (iv) a linear light guide disposed between the at least one forward facing light source and the diffusing distal tip;
• (b) administering a photoreactive agent to target vascular tissue in a patient, the photoreactive agent having a characteristic absorption waveband corresponding to the characteristic emission waveband of the at least one light source;
• (c) advancing the vascular illumination apparatus through the vascular system of the patient until the at least one light source is disposed adjacent to the vascular target tissue;
• (d) energizing the at least one light source to cause the at least one light source to emit light;
• (e) directing the light emitted by the at least one light source toward a distal end of the vascular illumination apparatus along a linear path;
• and
• (f) diffusing and emitting light from the distal end of the vascular illumination apparatus to administer the light to the vascular target tissue, the application of the light to the vascular target tissue resulting in at least one of a therapeutic effect and generation of diagnostic data.

A method for using photodynamic therapy to treat vascular tissue, comprising the steps of:

• (a) providing a vascular illumination apparatus comprising an elongate flexible body having a proximal end, a distal end, a guidewire that includes a light emitting portion proximate the distal end, the light emitting portion including at least one light source, and at least one expandable member overlapping the light emitting portion;
• (b) administering a photoreactive agent to target vascular tissue in a patient, the photoreactive agent having a characteristic absorption waveband corresponding to the characteristic emission waveband of the light source element
• (c) advancing the vascular illumination apparatus through the vascular system of the patient until the light emitting portion is disposed adjacent to the vascular target tissue, such that a guidewire is slidably disposed in the elongate flexible body;
• (d) actuating the at least one expandable member to fix a position of the light emitting portion relative to the vascular target tissue;
• (e) advancing a light emitting member through the elongate flexible body until the light emitting member is proximate the light emitting portion of the vascular illumination apparatus;
• and
• (f) activating the light emitting member portion of the guidewire to cause light to be emitted from the light emitting portion of the vascular illumination apparatus to administer light to the vascular target tissue, the application of light to the vascular target tissue resulting in at least one of a therapeutic effect, and generation of diagnostic data.