Drill device and method for forming microconduits

• US 7,848,799 B2
• Filed: 08/17/2005
• Issued: 12/07/2010
• Est. Priority Date: 03/25/2003
• Status: Active Grant

• Current Assignee: Galderma Pharma SA (Galderma Holding SA)
• Original Assignee: Galderma Pharma SA (Galderma Holding SA), Path Scientific, LLC
• Inventors: Herndon, Terry O.
• Primary Examiner(s): Hindenburg; Max
• Assistant Examiner(s): SZMAL, BRIAN SCOTT
• Application Number:
  US11/206,232
• Publication Number:
  US 20060041241A1
• Time in Patent Office: 1,938 Days
• Field of Search: 600/547, 125/1, 294/070.5, 295/93, 29/1.R, 29/12, 29/15, 29/7, 408/146, 408/103, 408/108, 408/109, 408/136, 408/180, 175/20, 175/50, 175/55, 175/58, 175/87, 175/122, 175/170, 175/203, 175/316
• US Class Current: 600/547
• CPC Class Codes: A61B 17/1695 Trepans or craniotomes, i.e. specially adapted for drilling thin bones such as the skull
• CPC Class Codes: A61B 17/205 Vaccinating by means of needles or other puncturing devices
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00747 Dermatology
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61M 37/0076 Tattooing apparatus apparatus for marking animals A01K11/00; vaccine applicators having needles or other puncturing means A61B17/205
• 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: A61N 1/327 for enhancing the absorption properties of tissue, e.g. by electroporation

Abstract

The present invention relates to methods and devices for formation of microconduits in tissue, particularly using an impedance sensing drill to form microconduits. One embodiment of the invention is an impedance sensing drill comprising a drilling assembly, a control module, mechanically connected to the drilling assembly for controlling the depth of drilling by the drilling assembly; and a sensor, electrically connected to the drilling assembly and control module for detecting a change in an electrical impedance of a material being drilled. Another embodiment is a method of forming a microconduit in a material, which comprises the steps of drilling into the material, monitoring an electrical impedance of the material, and stopping the drilling into the material when a change in the impedance is detected, thereby forming microconduit.

Claims

1. An impedance sensing drill comprising:

a drilling assembly including a motor and a cutter which is adapted to be moved into and out of a tissue being drilled for the formation of microconduits;

a control module mechanically connected to the drilling assembly for controlling the depth of drilling by the drilling assembly; and

a sensor, electrically connected to the drilling assembly and the control module, for detecting a change in an electrical impedance of the tissue being drilled;

wherein, upon detection of a change in the electrical impedance, the sensor sends a signal to the control module of the drill to automatically reverse the forward motion of the cutter to withdraw the cutter from the tissue, and thereby control the depth of the drilling.

2. The impedance sensing drill of claim 1, wherein the electrical impedance being measured is electrical resistance.

3. A method of forming a microconduit in mammalian tissue, which comprises the steps of drilling into the tissue with an impedance sensing drill according to claim 1, monitoring an electrical impedance of the tissue, and stopping the drilling into the tissue and automatically reversing the forward motion of the cutter with the control module when a change in the electrical impedance is detected, thereby forming a microconduit in the tissue.

4. The method of claim 3, wherein the mammalian tissue is selected from the group consisting of tissue, stratum corneum, epidermis, dermis, cartilage, nails, and bone.

5. The method of claim 4, wherein the mammalian tissue is nail tissue.

6. A method of forming a microconduit in mammalian tissue, which comprises the steps of drilling into the tissue with a drilling assembly including a motor and a cutter, monitoring electrical impedance of the tissue with a sensor, and stopping the drilling into the tissue and automatically reversing the forward motion of the cutter with a control module when a change in the electrical impedance is detected by the sensor, thereby forming a microconduit in the tissue.

7. The method of claim 6, wherein the mammalian tissue is selected from the group consisting of tissue, stratum corneum, epidermis, dermis, cartilage, nails, and bone.

8. The method of claim 7, wherein the mammalian tissue is nail tissue.

9. The method of claim 6, wherein the electrical impedance being measured is electrical resistance.

10. An impedance sensing drill comprising:

a drilling assembly including a cutter;

a control module mechanically connected to the drilling assembly for controlling the depth of drilling by the cutter;

a sensor, electrically connected to the drilling assembly and control module for detecting a change in an electrical impedance of mammalian tissue being drilled; and

a mount allowing the cutter to move into or out of mammalian tissue being drilled;

wherein upon detection of a change in the electrical impedance in the mammalian tissue, the sensor sends a signal to the control module which automatically withdraws the cutter from the tissue.

11. The impedance sensing drill of claim 10, wherein the impedance sensing drill is computer controlled.

12. The impedance sensing drill of claim 10, wherein the mammalian tissue is selected from the group consisting of tissue, stratum corneum, epidermis, dermis, cartilage, nails, and bone.

13. The method of claim 12, wherein the mammalian tissue is nail tissue.

14. The impedance sensing drill of claim 10, wherein the electrical impedance characteristic being measured is electrical resistance.

15. An impedance sensing drill comprising a drilling assembly including a housing adapted to be placed in contact with a tissue being drilled;

a motor and a cutter rotated by the motor which is mobile in translation in the housing and which is adapted to be moved into and out of the tissue being drilled for the formation of microconduits;

a control module mechanically connected to the drilling assembly for controlling the translation of the cutter in the housing and into and out of the tissue being drilled; and

a sensor, electrically connected to the drilling assembly and to the control module for detecting a change in an electrical impedance between the cutter and the surface of the tissue being drilled when the cutter is translated in the tissue being drilled;

wherein the sensor, upon detection of a change in the electrical impedance corresponding to a transition between portions of the material being drilled, sends a signal to the control module to automatically reverse the direction of the cutter, thereby withdrawing the cutter from the tissue being drilled, and thereby controlling the depth of the drilling.