A device for crossing a lesion in a tissue lumen includes a crossing wire configured to pass through a lumen of a catheter, the crossing wire including a loop at a distal end of the crossing wire. The loop can have a configuration that prevents a width of the loop from exceeding a width of the tissue lumen, and the loop having a pair of lateral opposing portions configured for alignment with a wall of the tissue lumen and a leading portion interconnecting the pair of lateral opposing portions, the leading portion being configured to interrogate the lesion. The loop has a length in an axial direction of the crossing wire extending from the leading portion to proximal ends of the pair of lateral opposing portions, the length being perpendicular to the width, and the length of the loop is at least twice the width of the loop.
