MAGNETIC RESONANCE IMAGING INTERFERENCE IMMUNE DEVICE

• US 20080129435A1
• Filed: 10/29/2007
• Published: 06/05/2008
• Est. Priority Date: 06/24/2003
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: GRAY, Robert W.
• Granted Patent: US 7,839,146 B2
• Time in Patent Office: Days
• US Class Current: 336/184
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/086 Magnetic resonance imaging [MRI] compatible leads
• CPC Class Codes: A61N 1/3718 Monitoring of or protection against external electromagnetic fields or currents
• CPC Class Codes: H01F 5/00 Coils superconducting coils H01F6/06; fixed inductances of the signal type H01F17/00
• CPC Class Codes: H03H 1/0007 of radio frequency interference filters

Abstract

A medical apparatus includes a medical assist device to process signals to relating biological functions. A first lead is operatively connected to the medical assist device, the first lead having a distal end and a proximal end. A second lead is operatively connected to the medical assist device, the second lead having a distal end and a proximal end. The first electrode is operatively connected to the distal end of the first lead, and a second electrode is operatively connected to the distal end of the second lead. A filter circuit is operatively connected near the distal end of the first lead and the distal end of the second lead. A compensation circuit, operatively connected to the first lead, provides a compensation voltage to enable the filter to effectively block changing magnetic fields induced current in the second lead from passing through the second electrode of the distal end of the second lead.

Claims

1. A medical lead, comprising:

a conductor having a first section of coils and a second section of coils;

said first section of coils having coils coiled along an axis of a length of the medical lead;

said second section of coils having coils coiled perpendicular to the coils of said first section.

2. The medical lead as claimed in claim 1, wherein said conductor has a third section of coils, said third section of coils having coils coiled perpendicular to the coils of said first section and perpendicular to the coils of said second section.

3. The medical lead as claimed in claim 1, wherein said first section of coils has a predetermined number of coils per unit length, said second section of coils has a predetermined number of coils per unit length, and the predetermined number of coils per unit length of said first section of coils is different than the predetermined number of coils per unit length of said second section of coils.

4. The medical lead as claimed in claim 3, wherein said third section of coils has a predetermined number of coils per unit length, the predetermined number of coils per unit length of said first section of coils is different than the predetermined number of coils per unit length of said third section of coils, and the predetermined number of coils per unit length of said third section of coils is different than the predetermined number of coils per unit length of said second section of coils.

5. A medical lead, comprising:

a conductor having a plurality of first sections of coils and a plurality of second sections of coils, each first section of coils having coils coiled along an axis of a length of the medical lead, each second section of coils having coils coiled perpendicular to the coils of said first section.

6. The medical lead as claimed in claim 5, wherein said conductor has a plurality of third sections of coils, each third section of coils having coils coiled perpendicular to the coils of said first section and perpendicular to the coils of said second section.

7. The medical lead as claimed in claim 5, wherein each first section of coils has a predetermined number of coils per unit length, each second section of coils has a predetermined number of coils per unit length, and the predetermined number of coils per unit length of said first sections of coils is different than the predetermined number of coils per unit length of said second sections of coils.

8. The medical lead as claimed in claim 6, wherein each third section of coils has a predetermined number of coils per unit length, the predetermined number of coils per unit length of said first sections of coils is different than the predetermined number of coils per unit length of said third sections of coils, and the predetermined number of coils per unit length of said third sections of coils is different than the predetermined number of coils per unit length of said second sections of coils.