Virtual probe for a stereotactic digitizer for use in surgery

• US 6,409,686 B1
• Filed: 04/14/2000
• Issued: 06/25/2002
• Est. Priority Date: 01/24/1994
• Status: Expired due to Fees

• Current Assignee: Integra Burlington MA, Inc. (Integra LifeSciences Holdings Corporation)
• Original Assignee: Sherwood Services AG
• Inventors: Guthrie, Barton L., Daniels, Robert A.
• Primary Examiner(s): HINDENBURG, MAX F
• Application Number:
  US09/549,752
• Time in Patent Office: 802 Days
• Field of Search: 128/922, 600/459, 600/461, 600/587, 600/595, 604/117, 606/130
• US Class Current: 600/587
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2090/062 penetration depth
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 90/10 for stereotaxic surgery, e.g. frame-based stereotaxis
• CPC Class Codes: A61B 90/36 Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: A61B 90/50 Supports for surgical instruments, e.g. articulated arms

Abstract

This invention relates to a three-dimensional digitizer and a probe means associated with said digitizer that enables a virtual target point to be visualized and depth and range measurements to that target to be determined. In one embodiment, a mechanical articulated arm or other type of 3-D digitizer is used in conjunction with a graphics workstation which displays images from CT, MR, or other scanning means of the anatomy. By registration of the digitizer to the patient'"'"'s physical anatomy, a representation of the digitizer on the display means of the graphics workstation is possible. The position of the digitizer will be displayed in its quantitative relationship to the patient'"'"'s anatomy, including internal pathologies such as tumors. The end means of the 3-D digitizer could be a holder or fixation device which can accept a sliding probe. The probe, for example, could be a shaft which slides in a spring-loaded or non-spring-loaded fashion within the fixation means of the digitizer. The degree of extension of the probe from the fixation means can be read out by a scale, which might be engraved on the shaft of the sliding probe. The digitizer, when calibrated to the anatomy, would register a target point and also a direction of the probe as it would approach that point, as seen on the graphics workstation. There may be a pre-determined relationship of the virtual tip of a probe relative to the fixation means as it scans the anatomy with the probe moving in space. The physical probe might be the sliding rod, which will be retractile within the fixation means. Thus, by knowing the degree of retraction, one can gauge the distance from the tip of the sliding probe to the virtual target, as calculated in the 3-D graphic workstation.

Claims

1. Apparatus for determining probe depths within a human body by means of computer graphic assisted stereotaxy, comprising:

a probe adapter;

a slide probe adapted to be coupled to and slide with respect to said probe adapter along a line parallel to a probe direction defined by said probe adapter, said slide probe having a slide probe tip which is adapted to contact portions of said anatomy;

readout means cooperatively coupled to said slide probe to provide a distance readout corresponding to the distance of said slide probe tip with respect to said probe adapter;

a freehand three-dimensional digitizer coupled to said probe adapter, said digitizer adapted to provide position data corresponding to said probe direction and a predetermined probe tip position and corresponding to a position of said slide probe tip relative to said probe adapter, said position data further being defined with respect to the anatomy of a patient when said three-dimensional digitizer is calibrated in position relative to said anatomy;

computing means in communication with said three-dimensional digitizer, said computing means configured to

(i) display on display means said position of said slide probe tip relative to said probe adapter and said probe direction in relation to said anatomy; and

(ii) accept scanner image data of said anatomy;

whereby in use when said three-dimensional digitizer is near said anatomy, said probe direction and said probe tip can be moved to a desired position relative to said anatomy and a desired target in said anatomy as represented on said display means, and said distance readout of said readout means can be a gauge of the depth from said slide probe tip to said target when said slide probe tip contacts a part of said anatomy.

2. The apparatus of claim 1, wherein said three-dimensional digitizer is one of a mechanically encoded arm, an optically coupled device, an electromagnetically coupled device, and an ultrasonically coupled device.

3. The apparatus of claim 1, wherein said slide probe is a rod-like probe with a distance scale that is cooperatively connected to said slide probe such that when said slide probe moves with respect to said probe adapter, said distance scale provides a measure of the relative position of said slide probe relative to said probe adapter whereby said depth of said slide probe tip with respect to said target can be read off of said scale.

4. The apparatus of claim 3, wherein said distance scale provides a measure of the distance from the external anatomy to the target.

5. The apparatus of claim 3, wherein said distance scale is one of an electronic digital translation readout scale, and a slide carrier coupled to a millimeter scale.

6. An apparatus for facilitating performance of a surgical procedure, which comprises:

a probe;

a probe holder for holding the probe and defining a probe axis of direction, the probe holder adapted to permit movement of the probe relative to the probe holder along the probe axis of direction to thereby assume a predetermined relative position of the probe relative to the probe holder;

a digitizer for providing position data with respect to an anatomical portion of a patient and relating to the probe axis of direction and to the predetermined relative position of the probe; and

a computer for processing image scan data of an anatomical portion of a patient and for accepting the positional data, and having a display for displaying an image corresponding to the predetermined relative position of the probe and the probe axis of direction relative to the anatomical portion.

7. The apparatus according to claim 6 including readout indicia associated with the probe for determining the predetermined relative position of the probe to thereby provide an indicator relating to a distance between the probe and an internal target within the anatomical portion.

8. A distance determining apparatus for use with a three-dimensional digitizer having a probe adapter, the digitizer providing positional data corresponding to a direction of the probe adapter and a position of the probe adapter with respect to a patient'"'"'s anatomy, and with the positional data being inputted to a computer graphic workstation having a display that displays the predetermined tip end position and the predetermined probe adapter direction, the distance determining apparatus comprising:

(a) a depth probe mechanically coupled to the probe adapter and movable with respect to the probe adapter along a line parallel to the direction, the depth probe having a end adapted to contact portions of the patient'"'"'s anatomy; and

(b) a readout associated with the probe for indicating a relative position of the probe relative to the probe adapter whereby in use when the three-dimensional digitizer is near the anatomy, the direction and position of the probe adapter can be moved relative to the anatomy and a desired target in the anatomy as represented on the computer graphic workstation display, and the readout is a gauge of the depth from the probe end to the target when the probe contacts a part of the anatomy.

9. The apparatus of claim 8 wherein the probe is a rod-like probe with a distance scale that is cooperatively connected to the probe such that when the probe moves with respect to the probe adapter, the distance scale provides a measure of the relative position of the depth probe relative to the probe adapter whereby the depth of the probe end with respect to the target can be read off of the distance scale.

10. The apparatus of claim 8 wherein the probe is spring loaded with respect to the probe adapter so that when the probe contacts the anatomy, the probe can retract within the probe adapter freely and with a spring bias so that it will tend to continuously contact anatomy as the three-dimensional digitizer is passed over the anatomy, thereby providing a continuous indication of the distance.

11. Apparatus for facilitating performance of a surgical procedure, which comprises:

probe means including a probe adapter and a probe coupled to the probe adapter, the probe adapted to move with respect to the probe adapter along a line parallel to a probe direction defined by the probe adapter, the probe having a probe tip for contacting a portion of an anatomy of a patient;

digitizer means for providing positional data corresponding to the probe direction and a probe tip position;

computer processing means for accepting the positional data and for accepting scanner image data of the portion of the anatomy; and

computer display means for displaying the probe direction and the probe tip position with respect to the portion of the anatomy.

12. The apparatus according to claim 11 further including measuring means coupled to the probe means for measuring a relative position of the probe relative to the probe adapter.