A catheter facilitating traversal of restrictions in body conduits includes a shaft having a distal tip with a shape that is non-conical, radially twisted, and rectangular in radial cross section. An outer surface of the tip includes at least one side section extending from a blunt point radially outwardly with progressive positions proximally along an axis of the tip. The side section includes a proximal portion in proximity to the shaft, and a distal portion twisted radially with respect to the proximal portion. The catheter can be adapted for placement over a guidewire and can be made transparent thereby facilitating visualization through an endoscope in the catheter.