Contact over-torque with three-dimensional anatomical data

• US 7,751,867 B2
• Filed: 12/20/2005
• Issued: 07/06/2010
• Est. Priority Date: 12/20/2004
• Status: Active Grant

• Current Assignee: Stereotaxis, Inc.
• Original Assignee: Stereotaxis, Inc.
• Inventors: Viswanathan, Raju R.
• Primary Examiner(s): Le; Long V
• Assistant Examiner(s): HOFFA, ANGELA MARIE
• Application Number:
  US11/314,826
• Publication Number:
  US 20070137656A1
• Time in Patent Office: 1,659 Days
• Field of Search: None
• US Class Current: 600/424
• CPC Class Codes: A61B 1/00158 using magnetic field
• CPC Class Codes: A61B 34/73 Manipulators for magnetic surgery
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure

Abstract

A method is provided for establishing contact of a medical device against a three-dimensional surface geometry within a subject body, the method comprising obtaining a three-dimensional tissue surface geometry of an anatomical region within the subject body, obtaining a target location on the surface for the device to contact, determining local surface geometry information in a neighborhood of the target location, and using this information to determine a change of at least one control variable for effecting an over-torque of the medical device to enhance contact of the device with the target surface.

Claims

1. A method for establishing enhanced contact of a medical device against a three-dimensional surface geometry within a subject body, the method comprising:

obtaining a target location on a surface within a subject body for a medical device to contact by using an imaging device,

obtaining local surface geometry information in a neighborhood of the target location, wherein the local surface geometry information includes local surface normal and curvature information determined from at least two points within a local tangent plane containing the target location that are spaced a predetermined distance from the target location, which are used to measure the deviation away from the local tangent plane of a local surface patch;

using the local surface geometry information to determine a change of at least one control variable for effecting an over-torque of the medical device to enhance contact of the medical device with the target location on the surface; and

applying the change of the at least one control variable to effect an over-torque and enhance contact of the medical device against the surface.

2. The method of claim 1 wherein the deviation away from the local tangent plane is found by a stepping process that comprises incrementally moving a minimum distance from the at least two points, and determining whether an image intensity threshold, a point where intensity changes from a low value to a high value, has been crossed to determine if the surface is negatively curved or positively curved.