Method and apparatus for performing sonomammography and enhanced X-ray imaging

• US 5,664,573 A
• Filed: 11/16/1995
• Issued: 09/09/1997
• Est. Priority Date: 10/29/1993
• Status: Expired due to Term

• Current Assignee: United States Surgical Corporation (Medtronic Plc)
• Original Assignee: Neovision LLC (Medtronic Plc)
• Inventors: Shmulewitz, Ascher
• Primary Examiner(s): JAWORSKI, FRANCIS J
• Application Number:
  US08/559,077
• Time in Patent Office: 663 Days
• Field of Search: 128/653.1, 128/660.09, 128/915, 378/37
• US Class Current: 600/445
• CPC Class Codes: A61B 10/0233 Pointed or sharp biopsy instruments
• CPC Class Codes: A61B 17/3403 Needle locating or guiding means guides for suture needles A61B17/0482; guiding or tracking by nuclear magnetic resonance G01R33/285
• CPC Class Codes: A61B 2017/00902 transparent or translucent
• CPC Class Codes: A61B 2017/00924 for ultrasonic waves
• CPC Class Codes: A61B 2562/168 Fluid filled sensor housings
• CPC Class Codes: A61B 6/4291 the detector being combined with a grid or grating
• CPC Class Codes: A61B 6/4417 related to combined acquisition of different diagnostic modalities
• CPC Class Codes: A61B 6/502 for diagnosis of breast, i.e. mammography
• CPC Class Codes: A61B 6/5247 combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound
• CPC Class Codes: A61B 8/0825 for diagnosis of the breast, e.g. mammography
• CPC Class Codes: A61B 8/4209 by using holders, e.g. positioning frames
• CPC Class Codes: A61B 8/4272 involving the acoustic interface between the transducer and the tissue
• CPC Class Codes: A61B 8/4483 characterised by features of the ultrasound transducer
• CPC Class Codes: A61B 90/17 for soft tissue, e.g. breast-holding devices
• CPC Class Codes: Y10S 128/915 Ultrasound mammography

Abstract

Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging. Methods are also provided for viewing and analyzing the ultrasound images. Apparatus and methods are also provided for enhancing X-ray images obtained from conventional mammographic systems, and with reduced overall X-ray dosage to the patient.

Claims

1. In apparatus for obtaining radiological images of biological tissue by passing X-ray radiation through a biological tissue to form an image in a receptor, the apparatus comprising an X-ray source for emitting X-ray radiation, an upper compression surface and a lower compression surface adapted for immobilizing the biological tissue therebetween, and a receptor disposed beneath the lower compression surface, the X-ray source disposed above the upper compression surface so that X-ray radiation emitted from the source passes through the biological tissue and is received by the receptor, the improvement comprising:

a compression plate that is radiolucent and sonolucent, the compression plate having an upper surface and a lower surface, the lower surface forming the upper compression surface;

an ultrasonic transducer disposed above the compression plate;

a gel pad for acoustically coupling a portion of the biological tissue to the ultrasonic transducer;

drive means for moving the ultrasonic transducer across the upper surface of the compression plate while the biological tissue remains immobilized between the upper and lower compression surfaces, so that the ultrasonic transducer generates a plurality of ultrasound images of the biological tissue that are in registration with the image formed in the receptor.

2. The apparatus as defined in claim 1 wherein the material has a periphery and the material is coupled around the periphery to a rigid frame.

3. The apparatus as defined in claim 1 wherein the biological tissue has an X-ray attenuation characteristic, the gel pad is disposed between the upper compression surface and the lower compression surface and in contact with the biological tissue, and the gel pad comprises a material that conforms to the shape of the biological tissue and has an X-ray attenuation characteristic near the X-ray attenuation characteristic of the biological tissue.

4. The apparatus as defined in claim 3 wherein the gel pad reduces scattering of the X-ray radiation relative to scattering of the X-ray radiation in air.

5. The apparatus as defined in claim 1 wherein the biological tissue comprises a portion of a patient and has a non-uniform shape and a surface area, the compression plate imposes a force on the biological tissue to compress the biological tissue to a uniform thickness, and the gel pad conforms to the non-uniform shape to distribute the force over the surface area and reduce discomfort in the patient.

6. The apparatus as defined in claim 5 wherein the gel pad comprises an adherent surface that assists in positioning the biological tissue between the upper compression surface and the lower compression surface.

7. The apparatus as defined in claim 1 further comprising lubricating means for providing a film of fluid between the ultrasonic transducer and the compression plate to lubricate and acoustically couple the ultrasonic transducer to the compression plate.

8. The apparatus as defined in claim 1 wherein the drive means further comprises:

a gantry support;

a gantry movably engaged with the gantry support for movement in the distal and proximal directions;

a carriage movably engaged with the gantry for lateral movement.

9. The apparatus as defined in claim 8 wherein the drive means further comprises:

a first motorized cable arrangement for driving the gantry along the gantry support;

a second motorized cable arrangement for driving the carriage along the gantry; and

circuitry for controlling operation of the first and second motorized cable arrangements.

10. The apparatus as defined in claim 1 further comprising:

a biopsy instrument support;

means for aligning the biopsy instrument support with the ultrasonic transducer so that a medical practitioner may perform a biopsy guided by the plurality of ultrasonic images.

11. A method of obtaining an X-ray image and a corresponding registered ultrasound image of biological tissue, comprising a series of steps of:

immobilizing a biological tissue with respect to a reference point;

exposing the biological tissue to X-ray radiation to generate an X-ray image of the biological tissue in a receptor;

generating a plurality of ultrasound images of the biological tissue by acoustically coupling an ultrasonic transducer to the biological tissue, without intervening movement of the biological tissue with respect to the reference point;

displaying any one of the plurality of ultrasound images corresponding to a predetermined location on the X-ray image;

storing the plurality of ultrasound images in a storage medium; and

retrieving any one of the plurality of ultrasound images from the storage medium corresponding to a predetermined location on the X-ray image.

12. The method as defined in claim 11 wherein the step of exposing the biological tissue to X-ray radiation is performed after the step of generating a plurality of ultrasound images.

13. The method as defined in claim 11 further comprising the steps of:

repeatedly generating and displaying a plurality of ultrasound images on a timewise basis;

inserting a biopsy instrument into the biological tissue so that a portion of the biopsy instrument is visible in the plurality of ultrasound images; and

maneuvering the biopsy instrument to a desired location within the biological tissue based on the X-ray image and the plurality of ultrasound images.

14. The method as defined in claim 11 further comprising the step of processing the plurality of ultrasound images to enhance the diagnostic capabilities of those images.

15. The method as defined in claim 11 further comprising the steps of:

repeatedly generating and displaying a plurality of ultrasound images on a timewise basis at a location within the biological tissue;

processing the plurality of ultrasound images at the location to provide an indicator corresponding to blood flow at that location.

16. Apparatus for performing an image-guided biopsy of biological tissue, the apparatus comprising:

a compression plate that is sonolucent, the compression plate having first and second surfaces, the first surface forming a compression surface against which the biological tissue is immobilized;

an ultrasonic transducer disposed adjacent the second surface, the ultrasonic transducer generating a plurality of ultrasound images of the biological tissue;

means for moving the ultrasonic transducer across the second surface while the biological tissue remains immobilized against the compression surface;

means for displaying selected ones of the plurality of ultrasound images;

a biopsy instrument support; and

means for aligning the biopsy instrument support with the ultrasonic transducer so that a biopsy may be performed that is guided by the plurality of ultrasonic images.

17. The apparatus as defined in claim 16 further comprising a gel pad for acoustically coupling a portion of the biological tissue to the ultrasonic transducer.

18. The apparatus as defined in claim 17 wherein the biological tissue comprises a portion of a patient and has a non-uniform shape and a surface area, the compression surface imposes a force on the biological tissue, and the gel pad conforms to the non-uniform shape to distribute the force over the surface area and reduce discomfort in the patient.

19. The apparatus as defined in claim 18 wherein the gel pad comprises an adherent surface that assists in positioning the biological tissue relative to the the compression surface.

20. A method of obtaining an ultrasound image of interior features of a biological tissue, comprising a series of steps of:

immobilizing the biological tissue with respect to a reference point;

generating a plurality of ultrasound images of the biological tissue with respect to the reference point by acoustically coupling an ultrasonic transducer to the biological tissue;

displaying selected ones of the plurality of ultrasound images;

repeatedly generating and displaying a plurality of ultrasound images on a timewise basis;

inserting a biopsy instrument into the biological tissue so that a portion of the biopsy instrument is visible in the selected ones of the plurality of ultrasound images; and

maneuvering the biopsy instrument to a desired location within the biological tissue based on the display of the selected ones of the plurality of ultrasound images.

21. The method as defined in claim 20 wherein the step of acoustically coupling the ultrasonic transducer to the biological tissue further comprises steps of:

providing a gel pad for acoustically coupling a portion of the biological tissue to the ultrasonic transducer; and

positioning the gel pad between the ultrasonic transducer and the biological tissue.

22. The method as defined in claim 21 wherein the biological tissue comprises a portion of a patient and has a non-uniform shape and a surface area and the step of immobilizing the biological tissue with respect to a reference point compresses the biological tissue, the method further comprising a step of conforming the gel pad to the non-uniform shape to distribute the force over the surface area and reduce discomfort in the patient.