Patent ID: 7534249

Claim:
An lumen opening device for treating a lumen in a blood vessel portion of a living being's vascular system, said device comprising an outer catheter, an instrument having an inner catheter, a working head, and pump means, said instrument arranged to be extended through said outer catheter to form a passageway therebetween, wherein said pump means comprises at least one helical pump with said working head of said instrument being arranged to operate on occlusive material in a blood vessel's interior portion to open a lumen therein for the freer flow of blood therethrough, whereupon some debris may be produced by the operation of said working head, said catheter comprising a distal end portion and being arranged such that the tolerances between said catheter and said helical pump allow said catheter to be flexible, said pump means introducing an infusate liquid at a first flow rate at said working head and withdrawing said liquid at a second and higher flow rate to create a differential flow in said lumen, whereupon at least a portion of any debris produced by the operation of said working head is withdrawn by said at least one helical pump through said passageway for collection remote from the occluded vessel portion and is prevented front flowing into any upstream blood vessel or downstream blood vessel.