Abstract: Non-occluding catheters and methods for delivering energy to a vessel wall without occluding blood flow through the vessel wall are disclosed. In particular, the invention uses an energy distributor connected to an expansion mechanism and a waveguide. The expansion mechanism causes the distributor to come into close proximity with a target region in the vessel wall, while maintaining at least one fluid passageway for blood flow throughout the instrument.

Abstract: A method for treating in-stent restenosis using radiation having a wavelength sufficient to kill or promote cellular death (e.g., through programmed cell death), or otherwise remove smooth muscle cells which have proliferated, or which might otherwise proliferate, in the proximity of (i.e., within, around or adjacent to) a stent within a body lumen, causing (or potentially causing) at least partial blockage of the lumen. The treatment method includes irradiating smooth muscle cells in the region of the stenosis with non-ablative, cytotoxic radiation, such as UV radiation. A cytotoxic, photoactivatable chromophore may also be delivered to the treatment site prior to irradiation. The method can be used prophylactically or to treat in-stent restenosis after blockage has occurred without further damage to surrounding tissue.

Abstract: A light delivery system for use in irradiating vascular tissue includes a balloon catheter with a working lumen for receiving an optical fiber therein and an inflation/flushing lumen adapted to receive a liquid at a proximal end and leading to a space defined within the balloon member attached to a distal end of the catheter. The balloon member has a pattern of holes or pores in the wall thereof through which the saline may flow when the balloon is inflated, causing any blood or other absorbing substances that may interfere with good radiant energy transmission to be flushed away from the treatment site.

Abstract: A light delivery system for use in irradiating vascular tissue includes a balloon catheter with a working lumen for receiving an optical fiber therein and an inflation/flushing lumen adapted to receive a liquid at a proximal end and leading to a space defined within the balloon member attached to a distal end of the catheter. The balloon member has a pattern of holes or pores in the wall thereof through which the saline may flow when the balloon is inflated, causing any blood or other absorbing substances that may interfere with good radiant energy transmission to be flushed away from the treatment site.

Abstract: Ultraviolet radiation can be used to treat vascular diseases. In particular, for unstable lesions where angioplasty may not be warranted, cytotoxic, nonablative ultraviolet radiation, preferably at a wavelength in the range of about 240 to about 280 nanometers, can be used to disable the intima and reduce spasms associated with partially occluded blood vessels.