Method and apparatus for providing related images over time of a portion of the anatomy using at least four fiducial implants

• US 4,945,914 A
• Filed: 07/18/1988
• Issued: 08/07/1990
• Est. Priority Date: 11/10/1987
• Status: Expired due to Term

• Current Assignee: Marker
• Original Assignee: George S. Allen
• Inventors: Allen, George S.
• Primary Examiner(s): Howell, Kyle L.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/223,975
• Time in Patent Office: 750 Days
• Field of Search: 128/653, 128/303 B, 364/413.18, 364/413.16, 364/413.22, 364/413.13, 378/901, 382/6
• US Class Current: 600/426
• CPC Class Codes: A61B 2090/363 Use of fiducial points
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 6/12 Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61B 90/10 for stereotaxic surgery, e.g. frame-based stereotaxis
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: Y10S 378/901 Computer tomography program or processor

Abstract

The present invention pertains to a fiducial implant for the human body that is detectable by an imaging system. The invention is comprised of a first portion and a second portion. The first portion is configured to be detected by an imaging system when placed beneath the skin. The second portion is configured for fixed attachment to a bone beneath the skin without penetrating entirely through the bone and without fracturing the bone. The first portion is of detectable size and comprised of a material for detection by an imaging system, and sufficiently small to avoid the distortion of the skin when placed at an interface between the skin and the bone. The first portion also has at least a portion which is spherical and defines a surface for cooperating with a tool for securing the second portion to the bone. Additionally, the placement of n fiducial implants, where n≧4 and is an integer, into a portion of anatomy of the human body allows for the recreation of a particular image slice of the portion of the anatomy taken by an imaging system with respect to a first time period, at subsequent imaging sessions and also with different scan modalities. This provides a doctor with the ability to accurately follow the progress of the portion of the anatomy of interest. Moreover, the existence of n fiducial implants allows a target to be identified without the portion of anatomy relative to an external coordinate system. The portion of anatomy with the target may then be operated on, for instance, robotically, or precisely irradiated.

Claims

1. A method for diagnosing the condition of certain internal portions of the human anatomy comprising:

a. implanting n fiducial implants in spatial relationship, where n≧

4 and is an integer, on a portion of the anatomy to be diagnosed;

b. taking a first series of images at parallel cross-sectional slices of fixed thickness of the portion of the anatomy to be diagnosed;

c. choosing 3 of the n implants to form a plane;

d. reformatting the images formed by said slices to be parallel to the plane formed by said fiducial implants;

e. taking a second series of images of parallel cross-sectional slices of the portion of the anatomy to be diagnosed;

f. reformatting the images formed by said second series to be parallel to the plane formed by said fiducial implants; and

g. comparing the images formed by said first series of slices with the images created by the said second series of slices to determine any differences for the purpose of diagnoses.

2. A method for providing comparable images over time of a portion of the anatomy having n fiducial implants, where n≧

4 and is an integer, comprising the steps of;

taking a first series of cross-sectional image slices of the portion of the anatomy at a first time period, said first series of image slices being taken through at least one of said fiducial implants, said n fiducial implants being spaced at given positions in the anatomy;

taking a second series of cross-sectional image slices of the portion of the anatomy at a second time interval;

reformatting at least one image slice of the anatomy formed from the second series of image slices taken at the second time period to provide a substantially identical cross-section of the anatomy as that shown in at least one image slice from the first series of image slices taken at the first time period.

3. The method for providing related images according to claim 2 including after the step of taking a first series of image slices the steps of defining an internal coordinate system with respect to the n fiducial implants, and determining the position of the internal coordinate system relative to the first series of cross-sectional engaging slices;

and

wherein the step of reformatting includes reformatting the second series of image slices taken at the second time period so that positions and directions of the second series of images slices correspond with positions and directions of the first series of image slices taken at said first time period.

4. A method for providing comparable images of a portion of anatomy having n fiducial implants, where n≧

4 is an integer, comprising the steps of;

a. taking a cross-sectional image slices of the portion of the anatomy during a first time period; and

b. reformatting an image of a specified view of the portion of the anatomy with respect to an internal coordinate system defined by 3 of the n implants.