A method and apparatus for fluid delivery enables navigation through tortuous, spatially restricted body anatomy to access narrow diameter body lumens for the continuous delivery of fluids, including therapeutic fluids, to the lumen in an atraumatic manner that avoids damage to the body lumen. The fluid delivery device can have a flexible conduit having a proximal end, a distal end, and a lumen extending along an interior of the flexible conduit providing a fluid flow path between the proximal and distal ends, where the lumen transitions into a micro-lumen exiting through a port through which a high concentration of fluid injected into the lumen exits laterally out along an image viewable zone at the distal end of the flexible conduit. The flexible conduit has a maximum outer diameter sized sufficient to navigate narrow diameter body lumens.