U.S. patent number 5,240,011 [Application Number 07/799,418] was granted by the patent office on 1993-08-31 for motorized biopsy needle positioner.
This patent grant is currently assigned to Fischer Imaging Corporation. Invention is credited to Michael Assa.
United States Patent |
5,240,011 |
Assa |
August 31, 1993 |
Motorized biopsy needle positioner
Abstract
A motorized biopsy needle positioner employed in a mammographic
needle biopsy system receives coordinate information representative
of a previously identified point of interest within a patient's
captive breast under examination and automatically positions a
biopsy needle in accordance with that coordinate information to
permit insertion of the biopsy needle to the previously identified
point of interest. An offset mode of operation of the motorized
biopsy needle positioner automatically positions the biopsy needle
in accordance with coordinate information representative of an
offset point within the patient's breast that is offset from the
previously identified point of interest to permit insertion of the
biopsy needle to that offset point. A manual mode of operation of
the motorized biopsy needle positioner permits the user to actuate
directional keys of a user control unit to position the biopsy
needle in one or more directions, as specified by the actuated
directional keys.
Inventors: |
Assa; Michael (Englewood,
CO) |
Assignee: |
Fischer Imaging Corporation
(Denver, CO)
|
Family
ID: |
25175865 |
Appl.
No.: |
07/799,418 |
Filed: |
November 27, 1991 |
Current U.S.
Class: |
600/564; 606/130;
606/167; 348/E13.026; 348/E13.018; 348/E13.014 |
Current CPC
Class: |
H04N
13/239 (20180501); A61B 90/17 (20160201); A61B
17/3403 (20130101); H04N 13/30 (20180501); H04N
13/254 (20180501); A61B 10/0233 (20130101) |
Current International
Class: |
A61B
17/34 (20060101); H04N 13/00 (20060101); A61B
19/00 (20060101); A61B 10/00 (20060101); A61B
006/00 () |
Field of
Search: |
;128/751-755
;606/167-170 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
"Stereotaxic Instrument for Needle Biopsy of the Mamma," Bolingren,
Tan et al, American Journal Roentgenology, vol. 129 pp. 121-125,
1977..
|
Primary Examiner: Cohen; Lee S.
Assistant Examiner: Nasser, Jr.; Robert L.
Attorney, Agent or Firm: Sheridan, Ross & McIntosh
Claims
I claim:
1. An apparatus for use in inserting a biopsy needle to a point of
interest within a patient's captive breast, comprising:
(a) biopsy needle positioning means for controllably retaining a
biopsy needle for movement within a spatial coordinate system that
encompasses a patient's captive breast, the biopsy needle
positioning means including motorized means for positioning said
biopsy needle in accordance with at least one specified coordinate
of the spatial coordinate system;
(b) controller means, coupled to said biopsy needle positioning
means, for receiving coordinate information that specifies at least
one coordinate of a point of interest within said patient's captive
breast;
(c) first user control means, coupled to said biopsy needle
positioning means, for enabling a user to initiate automatic
movement of said biopsy needle in accordance with coordinate
information received by said controller means and
(d) offset control means for controlling said biopsy needle
positioning means to move said biopsy needle in accordance with
offset coordinate information regarding an offset point that is
spatially offset from said point of interest so as to permit
insertion of said biopsy needle to the offset point within the
patient's captive breast.
2. The apparatus of claim 1, wherein said first user control means
includes display means for visually displaying coordinate
information that specifies coordinates of said point of interest in
the patient's captive breast.
3. The apparatus of claim 1, wherein said first user control means
includes display means for visually displaying offset coordinate
information that specifies coordinates of said offset point within
the patient's captive breast.
4. The apparatus of claim 1, further comprising:
safety interlock means, actuable by the user, for preventing
inadvertent movement of said biopsy needle.
5. The apparatus of claim 1, wherein said controller means is
operative for receiving coordinate information in the form of
horizontal angle, vertical angle, and insertion depth distance to
specify coordinates of said point of interest within the patient's
captive breast.
6. The apparatus of claim 1, wherein the controller means is
operative for receiving coordinate information in the form of x, y,
and z rectangular axes distances to specify coordinates of said
point of interest within the patient's captive breast.
7. The apparatus of claim 1, further comprising:
second user control means, coupled to said biopsy needle
positioning means, for enabling a user to initiate manual movement
of said biopsy needle responsive to input from the user.
8. The apparatus of claim 1, further comprising:
directional control means for designating movement of said biopsy
needle in one or more selected directions.
9. The apparatus of claim 8, wherein the directional control means
comprises up, down, left, and right arrow keys.
10. The apparatus of claim 8, further comprising:
display means for visually displaying coordinate information
corresponding to the position of said biopsy needle as it moves in
the one or more selected directions in response to actuation of
directional control means.
11. The apparatus of claim 1, further comprising:
driven retaining means for retaining and driving said biopsy needle
within the patient's breast to obtain a tissue sample from said
point of interest.
12. The apparatus of claim 1, further comprising:
immobilizing means for immobilizing the patient's breast relative
to said spatial coordinate system.
Description
REFERENCE TO RELATED PATENT
This application is related to allowed U.S. patent application Ser.
No. 07/440,775 entitled Precision Mammographic Needle Biopsy System
now U.S. Pat. No. 5,078,142, the subject matter of which is
incorporated herein by reference.
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates generally to medical mammography systems
that are designed to detect and biopsy non-palpable lesions of the
female breast. More particularly, this invention is directed to a
motorized biopsy needle positioner that automatically positions a
biopsy needle to allow insertion to a previously identified point
of interest in a patient's breast that is under examination.
Known mammographic needle biopsy systems, such as the Mammotest
system manufactured and marketed by Fischer Imaging Corporation,
Denver, Colorado, 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 of a puncture instrument 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 of these prior art mammographic biopsy systems
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 precisely to the
idenified point of interest.
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 a previously identified point
of interest within a patient's breast.
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
automatically position a biopsy needle to allow insertion of the
needle to a point within a patient's breast that is spatially
offset from a previously identified point of interest.
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.
DETAILED DESCRIPTION OF THE INVENTION
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 operates
conventionally in accordance with the teachings of the reference
cited above, for example, 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. While the three-dimensional or spatial
coordinates of the point of interest are expressed as polar
coordinates in the embodiment described herein, they may also be
expressed as coordinates in an X, Y, and Z rectangular 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 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 instrument
for insertion to the identified point of interest within the
patient's breast.
The biopsy needle positioning mechanism, illustrated in the
detailed diagram of FIG. 2, and typically employed as a component
of an overall mammographic needle biopsy system, comprises a
conventional puncture instrument 10 for retaining a biopsy needle
or other biopsy or therapeutic delivery device (not illustrated).
Three conventional DC motors 12, 14, and 16 are provided for moving
the biopsy needle retained by the puncture instrument 10 in the
rotation and angulation axes and for setting a stop position along
the depth axis, respectively. Positional feedback is provided to
the biopsy needle positioning motor controller by the three DC
motors 12, 14, and 16.
The operator hand controller allows the clinician user to control
the motorized biopsy needle positioning system. Controls are
provided to permit the user to initiate movement of the biopsy
needle into a position for insertion to the identified point of
interest within the patient's breast, in accordance with the
computed spatial coordinates of that point of interest. The
position of the biopsy needle may be monitored by the user with
reference to a 32-character display on the operator hand
controller. An enable switch is provided to prevent inadvertent
motion of the biopsy needle.
The remote view and display box receives the spatial coordinates of
rotation, angulation, and depth from the biopsy needle positioning
motor controller and displays them for the benefit of the clinician
user or others on a 40-character alphanumeric display. The remote
view and display box may be conveniently mounted on a table that
includes means for mounting and lighting x-ray reference films to
be viewed during a breast biopsy procedure.
Operation of the biopsy needle positioning motor controller may be
understood with reference to the detailed block diagram of FIG. 3.
The biopsy needle positioning motor controller receives the spatial
coordinates of the identified point of interest within the
patient's breast from the film digitizer and coordinates calculator
and computes the variables required to drive the three DC motors
12, 14, and 16 that form part of the biopsy needle positioning
mechanism. Information regarding the position of the biopsy needle
is continuously provided by the biopsy needle positioning motor
controller to the LED displays in the operator hand controller.
During manual operation, the biopsy needle positioning motor
controller receives commands from the operator hand controller and
drives the biopsy needle positioning mechanism in the direction
specified for as long as the user simultaneously depresses one of
the direction arrow keys and the enable switch located on the
operator hand controller illustrated in FIG. 4.
A central processing unit (8032 CPU) within the biopsy needle
positioning motor controller has a direct serial communications
link with the remote view and display box through an RS422 serial
transmitter U29. The 8032 CPU also has two bi-directional
communications links through a dual asynchronous universal
transmitter/receiver DUART, which provides serial communications
between the biopsy needle positioning motor controller and both the
film digitizer and coordinates calculator (serial channel B) and
the operator hand controller (serial channel A).
Under normal operating conditions, the 8032 CPU loads the three DC
motor controller sections (rotation, angulation, and depth) with
high level initial conditions data. This initial conditions data
includes velocity constants, acceleration constants, PID filter
information, and sample period. When the spatial coordinates of the
identified point of interest within the patient's breast, as
computed by the film digitizer and coordinates calculator, are
placed on the data bus AD0-AD7 by DUART U11, the 8032 CPU reads
these spatial coordinates and calculates the corresponding motor
control values. The 8032 CPU then sends this data to the three
motor control sections. The motor control sections calculate the
actual motor drive voltages and provide the drive voltages to
motors 12, 14, and 16 through separate H-bridge circuits. The motor
control sections monitor the encoder feedback from the biopsy
needle positioning mechanism to determine the position of the
biopsy needle and to adjust the motor drive voltages as the biopsy
needle reaches the identified point of interest. A typical motor
voltage and velocity profile is trapezoidal in nature, ramping up
to a start voltage, then holding constant, and finally ramping down
to a stop voltage when the biopsy needle has reached the position
required for insertion to the identified point of interest.
The 8032 CPU support circuits include operating and debug program
data in erasable programmable read-only memories EPROMs U1 and U6.
Fourteen status bits plus a six-bit DIP switch are monitored
through an input port and a random access memory RAM U15. The
status bits include .+-. limit switches and a home switch
associated with each coordinate axis. Two additional status bits
serve to monitor the +5-volt (+5ENC) and +24-volt (+24VOK) power
supplies. A reset circuit U23 provides a reset signal to reset the
8032 CPU when power is initially applied. The reset circuit also
monitors program execution by counting a pulse associated with each
cycle of the program and by executing a CPU reset command if the
pulses stop, as may occur during a software lockup.
Referring now to FIGS. 4 and 5, it will be understood how the
operator hand controller of FIG. 4 transmits data to and receives
data and instructions from the biopsy needle positioning motor
controller via an RS422 serial transmitter/receiver bus (serial
channel A). While the operator hand controller is described herein
as being a hand-held unit, it may also comprise a console or
table-mounted unit. The principal functions of the operator hand
controller are to 1) transmit switch closure data resulting from
actuation of the direction arrow keys and the MANUAL, OFFSET, and
TARGET keys to the biopsy needle positioning motor controller; 2)
illuminate button LEDs in accordance with information received from
the biopsy needle positioning motor controller; and 3) display the
spatial coordinates of the identified point of interest within the
patient's breast, as provided by the biopsy needle positioning
motor controller. Additionally, the operator hand controller
provides a safety interlock through the ENABLE switch SW9, which
must be simultaneously depressed by the user with a selected one of
the function keys in order to initiate any of the functions of the
operator hand controller. The ENABLE switch is mounted on the side
of the operator hand controller and, when depressed, energizes a
relay in the biopsy needle positioning motor controller that
enables movement of the biopsy needle positioning mechanism. When
this switch opens, the relay removes power from the three DC motors
12, 14, and 16 of the biopsy needle positioning mechanism.
The clinician user initiates control of the biopsy needle
positioning mechanism in either an automatic or manual mode by
depressing control switches on the operator hand controller.
Depressing one of the arrow keys or one of the MANUAL, OFFSET or
TARGET keys has the effect of grounding a corresponding input of
serial encoder U13. This causes serial encoder U13 to apply an
INTERRUPT 0 (INT00) to the CPU U9 and place the serial data in
I.sup.2 C protocol on the serial lines SDA and SCL to the CPU U9.
The CPU U9 converts the switch information to RS422 protocol and
sends it to the biopsy needle positioning motor controller via
serial transmitter U15. Each of the keys on the operator hand
controller contains a light emitting diode LED that is illuminated
under the control of the biopsy needle positioning motor
controller. The biopsy needle positioning motor controller selects
a particular LED to be illuminated, sets the brightness of that
LED, and determines how long that LED is to remain illuminated.
This information is sent to the -CPU U9 via serial receiver U15.
The CPU U9 then places the information in I.sup.2 C protocol on the
serial lines SDA and SCL to be transmitted to serial decoder/driver
U14. Serial decoder/driver U14 pulls a corresponding output to its
low state, thereby illuminating the selected LED. The CPU U9
controls the brightness of the LEDs on the operator hand controller
by setting the duty cycle of BRIGHTNESS (BL) pulses applied to the
LEDs. A 50% duty cycle illuminates the LEDs at half brightness and
a 100% duty cycle illuminates the LEDs at full brightness.
The position readout displays U1-U8 in the operator hand controller
provide two rows of displayed information comprising 16 ASCII
characters in each row. Each row comprises four display devices,
and each display device contains four 5.times.7 dot matrix
character displays. Referring to FIG. 4, the top line of the
position readout display indicates target number 2 (2:), a rotation
axis angle of 10.32 degrees right (10.32R), and an angulation axis
angle of 9.72 degrees up (9.72U). The bottom line of the postion
readout display indicates a depth stop setting of 135.6 millimeters
(135.6mm depth). As previously described in connection with the
LEDs that illuminate each of the keys of the operator hand
controller, the biopsy needle positioning motor controller
similarly controls the position readout displays through serial
communications with the operator hand controller CPU U9. The CPU U9
provides segment selection control and character display using two
data buses DD0-DD7 and DA0-DA4. To display a selected ASCII
character, the CPU U9 puts data describing the character on the
DD0-DD7 (P3.0-P3.6 outputs of the CPU U9) bus. The CPU U9 transmits
a low signal ENABLE (DWR) to segment decoder U10, which decodes
bits DA2-DA4 and applies a low enable signal to the appropriate
ones of display device U1-U8. The enabled display device then
decodes the character select bit DA0 and DA1 to select the
character position which displays the ASCII character defined by
data bus DD0-DD6. As with the LEDs, the biopsy needle positioning
motor controller defines the brightness of the position readout
display. The biopsy needle positioning motor controller
communicates the brightness level to the CPU U9, which then
switches the BRIGHTNESS (BL) signal on and off, producing the
designated duty cycle.
Referring now to FIG. 6, there is shown a flow chart of the
principal software program performed by the biopsy needle
positioning motor controller. All of the software represented by
the flow chart of FIG. 6 is stored in EPROMs U1 and U6 of the
biopsy needle positioning motor controller and is conventionally
written in 8051 assembly language. In accordance with block 1 of
the flow chart, the software performs several tasks on
initialization of the motorized biopsy needle positioner. When
power is first applied to the system, the reset circuit U23 within
the biopsy needle positioning motor controller applies a CPU reset
pulse to the 8032 CPU (U18). This reset pulse drives the 8032 CPU
to its intialization routine.
In accordance with block 2 of the flow chart of FIG. 6, following
the power on reset, the 8032 CPU initiates power on reset
diagnostics (PRD) which are a series of low level tests of the
system hardware to determine whether or not the hardware is working
well enough to permit operation to continue. If the power on
diagnostics are executed successfully, the 8032 CPU begins
performing a number of hardware and software initialization tasks.
These include 1) initializing the input/output (I/O) ports on the
operator hand controller and biopsy needle positioning motor
controller; 2) setting the output ports on the operator hand
controller and biopsy needle positioning motor controller to
default conditions; 3) clearing the input ports and memory
locations of RAM 15 in the biopsy needle positioning motor
controller; 4) resetting smart controllers U16 and U17 within the
biopsy needle positioning motor controller and loading control
parameters; 5) reading the operating program stored in EEPROMs U1
and U6 into the RAM portion of memory U15; 6) setting up the 8032
CPU internal timer 1 for 10-msec periodic interrupt; 7) setting up
the 8032 CPU internal timer 0 for 9600 baud rate; 8) setting up the
8032 internal universal asynchronous receiver/transmitter (UART)
for debug terminal/remote display; 9) initialization of dual UART
(DUART U20) in the biopsy needle positioning motor controller for
serial data transfers; and 10) performing miscellaneous variable
initialization as required.
In accordance with block 3 of the flow chart of FIG. 6, following
initialization, the 8032 CPU checks the condition of the key state
byte sent by the operator hand controller via serial communication
channel A and stored in RAM U15. If the operator hand controller
has sent an INTO byte indicating that a key has been depressed, the
software branches to interrogation block 4. If no keys have been
depressed, the software increments to interrogation block 10.
In accordance with block 4 of the flow chart of FIG. 6, the 8032
CPU checks the key state byte stored in RAM U15 to determine if the
key depressed is the TARGET key. If so, the software branches to
routine block 5. If the TARGET key has not been depressed, the
software increments to interrogation block 8.
In accordance with block 5 of the flow chart of FIG. 6, the 8032
CPU sends a request for the spatial coordinates of the identified
point of interest within the patient's breast to the film digitizer
and coordinates calculator via serial comunications channel B and
through DUART U20. The software then increments to routine block
6.
In accordance with block 6 of the flow chart of FIG. 6, the film
digitizer and coordinates calculator responds to a request for
spatial coordinates by sending a formatted data package containing
those spatial coordinates. This data package is automaticaly stored
in the XDATA buffer section of RAM U15. The software then
increments to routine block 7.
In accordance with block 7 of the flow chart of FIG. 6, the 8032
CPU initiates position display on the operator hand controller by
storing the data package containing the spatial coordinates of the
identified point of interest in the XDATA buffer of RAM U15. The
main program initiates transfer of the first character of the
display, via serial data communications channel A, and then turns
the data transfer task over to an interrupt handler subroutine
which completes transfer of the remaining 31 characters of
displayed information. When the transfer is complete, the software
increments to interrogation block 10.
In accordance with block 8 of the flow chart of FIG. 6, the 8032
CPU checks the key state byte from the operator hand controller to
determine if one of the direction arrow keys or the OFFSET key has
been depressed, thereby requiring movement of the biopsy needle
positioning mechanism. If so, the software branches to routine
block 9. If not, the software increments to interrogation block
10.
In accordance with block 9 of the flow chart of FIG. 6, the 8032
CPU loads "go to" data in the motor control circuits for each of
the rotation, angulation, and depth axes of the biopsy needle
positioning mechanism that represents the current identified point
of interest with the patient's breast. In addition to the position
data, the 8032 CPU issues start and enable commands to the smart
motor controllers U16 and U17. The program then increments to
interrogation block 10.
In accordance with block 10 of the flow chart of FIG. 6, the
software monitors the feedback position data from the smart motor
controllers U16 and U17 to determine if the biopsy needle
positioning mechanism is moving. If no movement is detected, the
software branches back to the beginning of the main program loop at
interrogation block 3, and the 8032 CPU issues a program loop pulse
to the reset circuit. If movement of the biopsy needle positioning
mechanism is detected, the program branches to routine block
11.
In accordance with block 11 of the flow chart of FIG. 6, the
program monitors the motor position data from the smart motor
controllers U16 and U17 on each axis. The new position data is
loaded into the XDATA buffer in RAM U15 and the first character is
transferred to the operator hand controller via serial
communications channel A by the main program. The remaining
characters are then transferred by the interrupt handler
subroutine. The program then increments to routine block 12.
In accordance with block 12 of the flow chart of FIG. 6, the
program checks all status and error information to determine 1)
whether any axis has reached a soft limit; 2) whether any axis has
reach a hard limit; or 3) whether any current limit been reached.
In addition, the smart controller status is checked to determine 1)
whether an excessive position error exists; 2) whether a wraparound
error has occurred; or 3) whether an index (center 0) has been
detected. The program then increments to interrogation block
13.
In accordance with block 13 of the flow chart of FIG. 6, the 8032
CPU compares current position data to the coordinates of the
indentified point of interest to determine if the biopsy needle
positioning mechanism is properly positioned for insertion of the
biopsy needle to the identified point of interest. If it is not at
the correct position, the program loops back to interrogation block
3 and the 8032 CPU issues a program loop pulse to the reset
circuits. If the biopsy needle positioning mechanism has reached
the target position, the program branches to routine block 14.
In accordance with block 14 of the flow chart of FIG. 6, the 8032
CPU issues a status byte to the smart motor controllers U16 and U17
for each axis, causing the motors to stop. The program then loops
back to interrogation block 3, and the 8032 CPU issues a program
loop pulse to the reset circuits.
As described in detail above, the software flowcharted in FIG. 6
controls the high level modes of operation of the motorized biopsy
needle positioner of the present invention. These modes of
operation include the JOG mode that enable manual control of the
motion of the biopsy needle, the HOME mode that places the biopsy
needle in the HOME position, the TARGET mode that drives the biopsy
needle into position for insertion to the identified point of
interest within the patient's breast, the OFFSET mode that drives
the biopsy needle into position for insertion to a point within the
patient's breast that is spatially offset from the identified point
of interest, and the ERROR mode in which certain error messages are
visually displayed to the user. In controlling the modes of
operation described above, the software of FIG. 6 processes key
commands received from the operator hand controller, generates
messages to be display on the operator hand controller, issues
requests to the film digitizer and coordinates calculator for data
relating to the spatial coordinates of the identified point of
interest, processes data received from the film digitizer and
coordinates calculator, issues commands for controlling movement of
the biopsy needle positioning mechanism, and performs state machine
type processing.
In addition, the software flowcharted in FIG. 6 performs motion
control by receiving commands from the mode control logic, by
generating commands to the smart motor controllers U16 and U17
within the biopsy needle positioning motor controller, and by
monitoring status during movement of the biopsy needle positioning
mechanism. The current motor positions and status information is
updated as required for the mode control logic to track the
movement of the biopsy needle positioning mechanism. Finally, the
software periodically sends messages for display on the remote view
and display box. These messages are collected by the interrupt
service routine and stored in RAM U15.
In operation, the clinician user initiates a breast biopsy
procedure by employing the film digitizer and coordinates
calculator to digitize an identified point of interest within the
patient's breast and to then compute the spatial coordinates of
that identified point of interest. The computed spatial coordinates
appear in the displays of the film digitizer and coordinates
calculator, the remote view and display box, and the operator hand
controller. The user then employs the operator hand controller to
automatically set the biopsy needle positioning mechanism such that
the biopsy needle retained therein is precisely positioned for
insertion to the identified point of interest by simultaneously
depressing the ENABLE and TARGET keys on the operator hand
controller. Once the identified point of interest has been sampled,
the user may wish to take a biopsy of the surrounding tissue. This
is accomplished by entering offsets in as many of the three
coordinate axes (rotation, angulation, and depth) as desired.
Offsets of 1 to 20 millimeters, in 1-millimeter increments, may be
entered by the user. To enter an offset, the user employs the film
digitizer and coordinates calculator to place the mouse on one of
the stereotactic images of the patient's breast and moves the
crosshairs of the mouse above, below, to the right, or to the left
of the identified point of interest. The user then clicks the mouse
button once for each millimeter of offset desired in that
direction. The three displays track the offset entered by the user
and display the number of millimeters of offset. The user must
simultaneously depress the ENABLE and OFFSET keys on the operator
hand controller to move the biopsy needle positioning mechanism to
the offset location. After that biopsy is completed, the user may
enter a new offset and repeat the above procedure to obtain a
biopsy at another point that is also spatially offset from the
original identified point of interest. Alternatively, the biopsy
needle positioning mechanism may be returned to the position
required for insertion of the biopsy needle to the original
identified point of interest by simultaneously depressing the
ENABLE and TARGET keys of the operator hand controller.
The user may disregard the identified point of interest and instead
select a manual mode of operation to move the biopsy needle
positioning mechanism as desired by first simultaneously depressing
the ENABLE and MANUAL keys of the operator hand controller. This
enables the four directional arrow keys of the operator hand
controller, which may then be actuated to provide manual control of
the rotation and angulation axes of the biopsy needle positioning
mechanism. The user simultaneously depresses the ENABLE key and one
of the directional arrow keys to drive the biopsy needle
positioning mechanism in the desired direction. The three displays
track this movement to provide a visual display of the movement of
the biopsy needle positioning mechanism as it occurs. To return the
biopsy needle positioning mechanism to the position required for
insertion of the biopsy needle to the original identified point of
interest within the patient's breast under examination, it is only
necessary for the user to simultaneoustly depress the ENABLE and
TARGET keys.
* * * * *