Devices and methods for recanalization of occluded body vessels using novel guidewires. A novel double-sided guidewire comprises a cross-section tapering from a more rigid middle section towards more flexible head sections. A first head of the guidewire is inserted into the occluded body vessel in a retrograde direction to traverse an occlusion. The guidewire is further advanced in the retrograde direction such that the first head and a portion of the middle section are retrieved from the body, thereby positioning the remainder of the guidewire traversing the occlusion in an antegrade direction and allowing for over the wire re-canalization techniques in the antegrade direction.