Drill device and method for forming microconduits

• US 9,022,949 B2
• Filed: 12/04/2013
• Issued: 05/05/2015
• Est. Priority Date: 03/25/2003
• Status: Active Grant

• Current Assignee: Path Scientific, LLC
• Original Assignee: Path Scientific, LLC
• Inventors: Herndon, Terry O.
• Primary Examiner(s): SZMAL, BRIAN SCOTT
• Application Number:
  US14/096,075
• Publication Number:
  US 20140094808A1
• Time in Patent Office: 517 Days
• Field of Search: 600/547, 606/80, 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: 600/573
• 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. A method of entry into the brain cavity when drilling through the bone of the skull, which comprises the steps of drilling into a target area with a drill bit, monitoring an electrical impedance of the target area, automatically stopping the drilling into the target area and automatically withdrawing the drill bit when a change in the electrical impedance is detected, thereby forming a microconduit or opening in the bone of the skull having the appropriate depth in the brain cavity.

2. The method of claim 1, wherein the drill bit comprises an endmill.

3. The method of claim 2, wherein the endmill comprises a carbide endmill.

4. The method of claim 3, wherein the endmill is 0.010 inches (0.254 mm) in diameter.