An apparatus is described for treating arterial occlusions combining an intraluminally operable catheter, having an occlusion-crossing working element, with a micro-invasive extraluminally operable locator for imaging the progress of the working element through the occlusion. Conical, abrasive, blunt-dissecting, and sharp-pointed, and steering and non-steering working elements including guide wires are described. Acoustic transducers and a flexible imaging tube are described for the locator. A suction cup is described for removably anchoring the imaging tube to a surface. A signal-emitting working element and cooperating signal-receiving locator are described. A method for treating arterial occlusions is described.