Case Western Reserve University

James D Sweeney

J Thomas Mortimer

Timothy J Crish

Gregory G Naples

A nerve trunk (A) has an annular electrode cuff (B) positioned therearound for imposing electrical signals on to the nerve trunk for the purpose of generating unidirectionally propagated action potentials. The electrode cuff includes an annular cathode (30) having a circular passage therethrough of a first diameter. An annular anode (40) has a larger circular passage therethrough of a second diameter, which second diameter is about 1.2 to 3.0 times the first diameter. A non-conductive sheath (50) extends around the anode, cathode, and nerve trunk. The anode and cathode are placed asymmetrically to one side of the non-conductive sheath. Specifically, a first length (L1) along the electrode sheath between a first end (56) and the cathode is at least twice a second length (L2) between the anode and cathode. A third length (L3) between the anode and a second end (58) of the conductive sheath is smaller than the first or second lengths. With this geometry, the majority of the current applied to the anode electrode flows to the cathode along path segments (62b and 62d) with lesser amounts of current flowing in the path segments (64a), (64b), (66a), and (66b).

Asymmetric shielded two electrode cuff

An electrode cuff (B) including a dielectric sleeve (10) and an annular cathode electrode (20) is disposed around a nerve trunk (A). An anode electrode (22) is disposed in body fluids in electrical communication with the nerve trunk. The cathode electrode is disposed off center within the dielectric sleeve. The flow of electric current from the anode to the cathode has a much greater amplitude along the nerve in the direction extending along the nerve trunk toward the cathode from the end of the dielectric sleeve toward which the cathode electrode is closest. A signal generator (C) applies a pulse train across the anode and cathode electrodes. The pulse train includes a plurality of alternating first amplitude pulse portions (40) and opposite polarity pulse portions (42). Each first polarity pulse includes a sharp leading edge (50) which rises abruptly to a preset amplitude (52). A trailing edge (56) of each first pulse portion decays smoothly into a leading edge (60) of each opposite polarity pulse portion without a discontinuity therebetween. The opposite polarity pulse portion has an amplitude (62) which is smaller than the triggering amplitude and a duration which is longer than the first polarity pulse portion duration. The amplitude and duration of the first and opposite polarity pulse portions are selected such that the net charge transfer in each direction is substantially the same.

Antidromic pulse generating wave form for collision blocking

A self-curling sheet (A) of non-conductive material is biased to curl into a tight spiral. A cut out (22) is removed from one corner of the sheet such that, when the sheet spirals, a passage (28) defined axially therethrough has one portion with a smaller diameter and another portion with a larger diameter. A pair of conductive strips (40, 50) are disposed on the self-curling sheet such that one extends peripherally around each of the larger and smaller diameter regions of the passage therethrough. The conductive segments may be electrically conductive for applying electrical impulses or fluid conductive for infusing medications. In use, a first edge (14) of the self-curling sheet is disposed adjacent a nerve trunk which is to receive the cuff therearound. The self-curling sheet is controllably permitted to curl around the nerve forming an annular cuff therearound.

Growing community of inventors

Cleveland Heights, OH, United States of America

James D Sweeney