US 11,903,666 B2
Magnetic wire for retrieval and elimination of calculus from the urinary tract
Tianjia Jessie Ge, Sunnyvale, CA (US); Simon Conti, Stanford, CA (US); Joseph C. Liao, Redwood City, CA (US); Kunj Raju Sheth, San Francisco, CA (US); and Shan X. Wang, Portola Valley, CA (US)
Assigned to The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US); and U.S. Government as represented by the Department of Veterans Affairs, Washington, DC (US)
Filed by The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US); and U.S. Government as represented by the Department of Veterans Affairs, Washington, DC (US)
Filed on Nov. 11, 2021, as Appl. No. 17/524,603.
Claims priority of provisional application 63/116,324, filed on Nov. 20, 2020.
Prior Publication US 2022/0160450 A1, May 26, 2022
Int. Cl. A61B 17/221 (2006.01); A61B 17/00 (2006.01); A61B 34/00 (2016.01); A61K 9/00 (2006.01); A61K 9/14 (2006.01); A61B 17/22 (2006.01)
CPC A61B 34/73 (2016.02) [A61B 17/221 (2013.01); A61K 9/0034 (2013.01); A61K 9/14 (2013.01); A61B 2017/0034 (2013.01); A61B 2017/00876 (2013.01); A61B 2017/22082 (2013.01); A61B 2034/731 (2016.02)] 10 Claims
OG exemplary drawing
 
1. A medical device for retrieval of kidney stone fragments from a urinary tract, comprising:
a plurality of magnets arranged within a flexible sheath forming a flexible wire,
wherein the magnets are magnetically attached end-to-end and arranged with their magnetic polarities alternating in direction;
wherein the magnetization direction of each of the magnets is orthogonal to the length axis of the flexible wire;
wherein there is a removable inner stylet within the flexible sheath allowing for modifiable flexibility of the wire;
wherein the medical device is dimensioned to be introduced into the urinary tract and standard endoscopic devices;
wherein the medical device is dimensioned to allow for the wire with magnetically attached stone fragments to be retrieved from the urinary tract;
wherein the magnetic field along the length axis is sufficient to attract to the surface of the flexible wire superparamagnetic nanoparticles which have bound themselves to kidney stone fragments; and
wherein the kidney stone fragments comprise calcium, uric acid, struvite, cystine or a combination thereof.