A method of removing vascular blockage includes providing a catheter system comprising an outer catheter with a serrated cutting element at its distal end, a bypass catheter, and a guidewire. In the catheter system, the bypass catheter is slidably disposed within the outer catheter. The method includes positioning a distal portion of the catheter system at a proximal end of an occlusion located within a vessel and moving the bypass catheter through the occlusion so that a medicated treatment solution may be delivered through the bypass catheter to an area of the brain or other tissue served by the vessel blocked by the occlusion. Both during and after the delivery of medicated treatment solution to the blocked part of the vessel with the bypass catheter, the physician may engage the occlusion with the cutting element by moving the outer catheter in a clockwise/counterclockwise or forward/backward direction within the outer catheter, cutting and then removing at least a portion of the occlusion from the vessel.
