Internal marker device for identification of biological substances

• US 6,628,982 B1
• Filed: 03/30/2000
• Issued: 09/30/2003
• Est. Priority Date: 03/30/2000
• Status: Expired due to Fees

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Thomas, Cherry T., Fisher, Susan J., Wahl, Richard L.
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): QADERI, RUNA S
• Application Number:
  US09/539,002
• Time in Patent Office: 1,279 Days
• Field of Search: 600/420, 600/431-436, 600/458, 200/302-303
• US Class Current: 600/431
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 6/037 Emission tomography
• CPC Class Codes: A61B 6/583 using calibration phantoms
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers

Abstract

The present invention is directed to a device for visualizing structure located on the interior of a biological substance. The device of the present invention includes a marker member which may be a solid cylinder or lumen having an interior volume. The marker member has a proximal end, and a distal end. The distal end of the device is removably insertable in the biological substance relative to the interior structure to be visualized and is composed of a biologically stable substrate material. An image-enhancing material is contained relative to the marker member in a manner such that the imaging material does not directly contact the biological substance; such imaging material will remain self-contained without causing significant tissue absorption, toxicity or undesired image distortion. The imaging material of choice is one which is capable of producing an emission or signal detectable external to the biological substance by suitable imaging instrumentation. Also disclosed is a method for visualizing critical structures or radiation therapy targets employing the device of the present invention, particularly in imaging processes such as positron emission tomography and/or single photon emission computerized tomography, MRI or ultrasound either used alone or in combination with anatomical imaging processes such as computerized tomography or mammography.

Claims

1. A method for visualizing at least one critical structure located in the interior of a biological system in conjunction with visualization of at least one region of interest, the region of interest visualizable in a process which results in at least one decay product generated by a positron emission event, the decay detectable external to the biological system, the visualization method comprising the steps of:

inserting a visualizing device into position in the interior of a physical cavity integral in the biological substance, the visualizing device having;

(a) a marker member composed of a biologically stable substrate material and having an interior, a proximal end, and a distal end, the distal end of the marker member adapted to be removably insertable in a cavity existing in the biological system and located relative to the interior structure to be visualized; and

(b) an imaging material contained in the marker member, the imaging material capable of producing emission detectable external to the biological substance in at lead one of position emission tomography and single photon emission computed tomography, the imaging material contained relative to the maker member in a manner such that the imaging material does not directly contact the biological substance;

recording and locating emissions from the imaging material contained in the marker member;

recording and localizing emissions from the region of interest emitting detectable signal;

integrating the emissions form the imaging material contained in the marker member and the emissions from the region of interest into translatable data; and

after recording and localizing the emissions from the imaging material and the region of interest, removing the visualizing device and essentially all imaging material contained therein from the interior of the biological substance.

2. The method of claim 1 further comprising the step of:

using the obtained data to reconstruct images for images fusion wherein the emissions and/or signal from the imaging material in the marker member are represented as a landmark, verification site or internal fiducial marker to drive registration of multiple data sets.

3. The method of claim 1 wherein the imaging material contained relative to the marker member includes at least one radiopharmaceutical material which produces at least one decay product generated by a positron emission event, the decay product detectable external to the biological system, and wherein the step of integrating emissions from the imaging material further comprises fusing data obtained from the positron emission event with data obtained from analysis of the region of interest to obtain to an image fusion of the region of interest relative to the marker member.

4. The method of claim 3 wherein the imaging material contained in the marker member further comprises a material selected from the group consisting of:

a. MRI contrast agents_selected from the group which includes paramagnetic and supermagnetic compounds;

b. CT contrast agents selected from the group which includes diatrizoate sodium and mixtures thereof; and

c. Ultrasound imaging materials.