Systems and methods for detecting tissue contact and needle penetration depth

• US 7,106,574 B2
• Filed: 08/23/2005
• Issued: 09/12/2006
• Est. Priority Date: 09/30/2002
• Status: Expired due to Fees

• Current Assignee: Advanced Cardiovascular Systems Incorporated
• Original Assignee: Advanced Cardiovascular Systems Incorporated
• Inventors: Beyerlein, Dagmar
• Primary Examiner(s): KENNEDY, SHARON E
• Application Number:
  US11/211,107
• Publication Number:
  US 20050283117A1
• Time in Patent Office: 385 Days
• Field of Search: 604/116, 604/117, 604/181, 604/21, 607/116, 607/118, 607/119, 607/122, 606/32, 361/313, 29/25, 29/41, 298/54
• US Class Current: 361/313
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61M 25/0084 being one or more injection needles
• CPC Class Codes: A61N 1/30 Apparatus for iontophoresis, i.e. transfer of media in ionic state by an electromotoric force into the body, or cataphoresis
• CPC Class Codes: Y10T 29/43 Electric condenser making
• CPC Class Codes: Y10T 29/49169 Assembling electrical component directly to terminal or elongated conductor

Abstract

A system for detecting tissue contact and penetration depth. The system comprises a needle sheath having a needle sheath inner diameter and a needle sheath outer diameter. A first conductive region is disposed on the needle sheath inner diameter. A needle having a needle insulation layer on the outer diameter upon which a second conductive region is disposed within the first conductive region. A dielectric layer is disposed between the first conductive tube and the second conductive tube. A capacitance sensor is coupled to the first conductive region and the second conductive region.

Claims

1. A method of making a capacitor for a delivery catheter comprising:

providing a needle sheath;

disposing a first conductive region within said needle sheath;

disposing a needle having a section covered with a needle insulation layer upon which a second conductive region is disposed within said needle sheath; and

coupling a capacitance sensor to said needle sheath to measure capacitance created by said first conductive region and said second conductive region.

2. The method of claim 1 further comprising:

disposing a ring within said needle sheath at a proximal end of said needle sheath wherein said needle is disposed into said needle sheath through said ring.

3. The method of claim 1 further comprising:

disposing a dielectric region between said first conductive region and said second conductive region.

6. The method of claim 1 further comprising:

disposing a dielectric region between said first conductive region and said second portion of said needle.

4. A method of making a capacitor for a delivery catheter comprising:

providing a needle sheath;

disposing a first conductive region within said needle sheath;

disposing a needle made out of a conductive material within said needle sheath, said needle having a first portion covered with an insulation layer and a second portion not covered by said insulation layer; and

coupling a capacitance sensor to said needle sheath to measure capacitance created by said first conductive region and said second portion of said needle.

5. The method of claim 4 further comprising:

disposing a ring within said needle sheath at a proximal end of said needle sheath wherein said needle is disposed into said needle sheath through said ring.