A light delivery apparatus to provide light treatment to a patient
includes a catheter assembly having a light source that transmit light
towards a target site within a patient. A balloon surrounds the light
source and has a plurality of tissue engaging elements movable between
first positions and second positions. In one embodiment, each element
extends radially inward in the first position and radially outward in the
second position. An insertion tool is used to deliver the light delivery
apparatus. During use, the light delivery apparatus is rotationally
locked with the insertion tool for improved steering, navigation, and
aiming of emitted light.