Motorized mammographic biopsy apparatus

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BACKGROUND OF THE INVENTION

This invention relates generally to mammography biopsy systems that are designed to detect and obtain cell or tissue samples from non-palpable lesions of the female breast. More particularly, this invention is directed to an advanced mammographic needle biopsy system incorporating a motorized biopsy needle positioner that automatically positions a biopsy needle to allow insertion to an identified point of interest in a patient's breast that is under examination.

Mammographic needle biopsy systems, such as a Mammotest system manufactured and marketed by Fischer Imaging Corporation, Denver, Colo., employ a computer-digitizer system to digitize the location of a point of interest within the patient's breast as that point of interest appears on a pair of stereo x-rays of the breast and to thereafter compute the three-dimensional or spatial coordinates of that point of interest and display them to the user. The user then manually sets these three-dimensional coordinates into respective position controls for a puncture instrument assembly and inserts a biopsy or other needle to the identified point of interest. These manual systems are susceptible to human error in setting the computed coordinates of the point of interest into the puncture instrument. In addition, manual setting of the coordinates of the point of interest is a time consuming operation that is frustrating to the patient, who is required to continue holding a position in which one of her breasts is under compression. Also, the clinician user is not permitted the flexibility of inserting the biopsy needle to a point within the patient's breast that is slightly offset from the previously identified point of interest because the coordinates provided by the computer-digitizer correspond only to the identified point of interest. It will be appreciated that such offset insertion in the present invention facilitates multiple pass sampling of a breast lesion using a driven biopsy instrument or other biopsy instrument as may be desired.

SUMMARY OF THE INVENTION

It is therefore a principal object of the present invention to provide a motorized biopsy needle positioner for mammographic needle biopsy systems that automatically positions a biopsy needle to permit insertion of the needle to an identified point of interest within a patient's breast, and preferably to points offset therefrom for multiple pass sampling.

It is a further object of the present invention to provide a motorized biopsy needle positioner for mammographic needle biopsy systems that includes a control unit for enabling the user to manually position a biopsy needle to allow insertion of the needle to a point within a patient's breast that is spatially offset from an identified point of interest.

It is an additional object of the present invention to provide an improved mammographic needle biopsy system in which a digitizer is employed to digitize the location of a point of interest within the patient's breast that appears on a pair of stereo X-rays that do not have coordinate scales depicted thereon and in which the vertical angle, horizontal angle, and insertion depth parameters defining that point of interest are automatically calculated and can be utilized by a motorized biopsy needle positioner to automatically position a biopsy needle with respect to at least some of these parameters.

It is another object of the present invention to provide an improved mammographic needle biopsy system in which a motorized biopsy needle positioner is used in conjunction with an examination table having an opening through which the patient's breast is permitted to pendulantly protrude so as to achieve highly accurate biopsy needle positioning.

It is a further object of the present invention to provide an improved mammographic needle biopsy system combinatively employing automatic positioning and offset features with a driven biopsy needle assembly which may comprise a spring loaded biopsy gun for rapid biopsy needle insertion into a patient's breast to obtain a tissue sample.

It is yet another object of the present invention to provide an improved mammographic needle biopsy system for combinatively immobilizing and imaging a pendulant breast disposed in a predetermined relationship to a predetermined frame of reference, automating the identification and spatial coordinate computation of a point of interest within the pendulant breast relative to the predetermined frame of reference, supportably disposing a driven biopsy needle assembly, or puncture instrument, in predetermined relation to the predetermined frame of reference, and automating the positioning of the driven biopsy needle assembly to permit insertion of a biopsy needle within the breast to the point of interest.

According to one embodiment of the present invention, an apparatus is provided for use in inserting a biopsy needle to a point of interest within a patient's captive breast. The apparatus comprises: a biopsy needle positioner for controllably retaining a biopsy needle for movement within a spatial coordinate system that encompasses the patient's captive breast, the biopsy needle positioner being motorized for positioning a biopsy needle in accordance with specified coordinates of a spatial coordinate system; a controller, coupled to the biopsy needle positioner, for receiving coordinate information that specifies the coordinates of a point of interest within the patient's captive breast; a user control mechanism, coupled to the biopsy needle positioner, for enabling a user to initiate automatic movement of a biopsy needle in accordance with coordinate information received by the controller; and, preferably, an offset control mechanism for controlling the biopsy needle positioner to move a biopsy needle in accordance with offset coordinate information pertaining to an offset point that is spatially offset from the point of interest so as to permit insertion of a biopsy needle to the offset point. The apparatus can further include a second user control mechanism for enabling the user to initiate manual movement of the biopsy needle and a mechanism for designating movement of the biopsy needle in one or more selected directions. Moreover, the apparatus can include a safety interlock, actuable by the user, for preventing inadvertent movement of the biopsy needle.

In accordance with another embodiment of the present invention, an apparatus for performing medical procedures on a pendulant breast of a patient in a prone position comprises: a table for supporting a patient in a prone position, the table having a breast apperture therein through which one of the patient's breasts is permitted to pendulantly protrude in a position within a predetermined frame of reference; a mechanism for compressing the pendulant breast of the prone patient into a mammographic position relative to the predetermined frame of reference; a transmitter and receiver, positionable relative to the predetermined frame of reference, for imaging the pendulant breast; an identifier for identifying a location of interest within the pendulant breast so as to permit determination of three dimensional coordinates of the identified location of interest; and a motorized mechanism for positioning a medical instrument, e.g. biopsy needle, relative to the predetermined frame of reference so as to permit the instrument to be inserted within the pendulant breast to the location of interest.

In accordance with a still further embodiment of the present invention, an apparatus for use in performing medical procedures on a patient's breast comprises: a mechanism for immobilizing a patient's breast in a mammographic position relative to a predetermined frame of reference; a transmitter and receiver, located in predetermined relation to and positionable relative to the predetermined frame of reference, for imaging the patient's breast; an identifier for identifying a location of interest within the patient's breast so as to permit determination of three dimensional coordinates of the identified location of interest; a driven retainer for retaining and driving a hollow tip biopsy needle within the patient's breast to obtain a tissue sample from the location of interest; and a motorized positioner for positioning the driven retainer relative to the predetermined frame of reference, wherein upon activating the driven retainer, the hollow tip biopsy needle is positionable within the patient's breast at the location of interest to obtain a tissue sample.

The present invention can advantageously be utilized to obtain a tissue sample suitable for histological diagnosis from a breast lesion. As is well known, such tissue samples yield a far greater degree of diagnostic information than can be obtained from cell samples asperated according to conventional techniques. The combination of features employed in the present invention provides increased accuracy and reliability to faciliate this contemplated histological purpose.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall block diagram of the motorized biopsy needle positioner of the present invention.

FIG. 2 is a pictorial diagram illustrating the biopsy needle positioning mechanism employed in the motorized biopsy needle positioner of FIG. 1.

FIG. 3 is a detailed block diagram of the biopsy needle positioning motor controller of FIG. 1.

FIG. 4 is a pictorial diagram of the operator hand controller of FIG. 1.

FIG. 5 is a detailed block diagram of circuitry employed in the operator hand controller of FIGS. 1 and 4.

FIG. 6 is a flow chart of the software program executed by the biopsy needle positioning motor controller of FIGS. 1 and 3.

FIG. 7 is a pictorial diagram illustrating a portion of a mammographic needle biopsy system constructed in accordance with the present invention.

FIG. 8 is a pictorial diagram illustrating the patient table of the mammographic needle biopsy system of FIG. 7 as being hinged to facilitate mounting and dismounting by the patient.

FIG. 9A Is a pictorial diagram illustrating the concave surface of the patient table of FIGS. 7 and 8, as well as a breast aperture in the patient table and an associated diaphragm cover therefor.

FIG. 9B is a cross sectional view of a portion of the patient table of FIG. 9A illustrating the positioning of the diaphragm cover between the table base and a padded cover therefor.

FIG. 9C is a plan view of the portion of the patient table of FIG. 9A that includes the breast aperture and diaphragm cover.

FIG. 10 is a pictorial diagram of a computer-digitizer console and cursor that are employed with the portion of the mammographic needle biopsy system illustrated in FIG. 7.

FIG. 11 is an electrical block diagram of the computer-digitizer console and cursor of FIG. 10.

FIG. 12A is a pictorial diagram illustrating the support and locking mechanism for a film holder arm and an X-ray arm that are part of the portion of the mammographic needle biopsy system illustrated in FIG. 7.

FIG. 12B is a cross sectional diagram illustrating the details of a tapered bearing support system for the X-ray arm of FIG. 12A.

FIG. 13 is a detailed mechanical diagram of the locking mechanism for the film holder and X-ray arms illustrated in FIGS. 7 and 12A.

FIGS. 14A-D are a detailed schematic diagram of circuity employed in the computer-digitizer console and cursor illustrated in the block diagram of FIG. 11.

FIG. 15 is a diagram illustrating the layout of the platen area of the computer-digitizer console of FIG. 10.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to mammographic systems which incorporate motorized positioners for positioning a medical instrument at a point of interest within a patient's breast. It will be appreciated that such a motorized positioner can be incorporated into a variety of mammographic systems. Such a motorized positioner is described below in connection with FIGS. 1-6. Thereafter, a particular embodiment of a mammographic system incorporating a motorized positioner is described in connection with FIGS. 7-15.

Referring now to the block diagram of FIG. 1, there is shown a motorized biopsy needle positioner that includes a film digitizer and coordinates calculator FDCC, a biopsy needle positioning motor controller BNPMC, a biopsy needle positioning mechanism BNPM, an operator hand controller OHC, and a remote view and display box RVDB. The film digitizer and coordinates calculator, an embodiment of which is described in more detail below in connection with FIGS. 7-15, operates to digitize a point of interest in a patient's breast under examination and to thereafter compute and display the three-dimensional or spatial coordinates of the digitized point of interest. Although the invention will be described with respect to a polar coordinate system, the three-dimensional or spatial coordinates of the point of interest can be expressed in polar coordinates, an X, Y, and Z rectangular coordinate system or other spatial coordinate system.

The biopsy needle positioning motor controller receives the computed spatial coordinates of an identified point of interest from the film digitizer and coordinates calculator and drives three conventional DC motors that serve to control a puncture instrument in its rotation (horizontal) and angulation (vertical) axes, and to set a stop position along its depth axis to position a biopsy needle or other device retained by the puncture instrum