MXPA00006601A - Method and apparatus for removing tissue from a region of interest using stereotacticradiographic guidance - Google Patents

Abstract

A method and apparatus for removing tissue from a volume surrounding a region of interest with a body part of a patient is disclosed. The tissue removal volume and location is determined by stereotactic radiography. The size of the tissue removal volume surrounding the region of interest is derived by placing boundaries around the region of interest in each stereotactic radiographic image. A tissue removal tool is moved within the derived tissue removal volume. The tissue in the region of interest which has been previously diagnosed as cancerous can be marked with a radioactive isotope, for example, and the removal of such tissue from the removal volume which surrounds the region of interest can be monitored to determine whether the tissue in the region of interest has been completely removed.

Description

METHOD AND APPARATUS TO REMOVE TISSUE FROM A REGION OF INTEREST USING A RADIOGRAPHIC GUIDE STEREOTACTICS Field of the Invention The present invention relates generally to a method and apparatus for removing tissue from a region of interest in a part of a patient's body. More particularly, the present invention relates to a method and apparatus for removing tissue from a region of interest in a part of a patient's body, such as the breast, wherein the removal of tissue is guided by stereotactic radiography.

Antecedents of the Invention Stereotactic mammography devices have been used to determine the three-dimensional coordinates of a region of interest in a breast, relative to the reference point of stereotactic apparatuses. The three-dimensional coordinates are generally used for diagnostic and surgical procedures, and more particularly, for inserting in the region of interest in the chest, the end of a cable, the tip of a biopsy needle or the tip of a surgical tool. rotating cut. The cables are usually used to guide a surgeon to the region of interest to eliminate part or all of what is found in that region. The biopsy needle is usually used to take samples of cells or tissue from the region of interest. The rotary cutting tool is generally used to remove tissue from the region of interest. In US Patent No. 5,289,520, which is incorporated in its entirety to the present description as a reference, an example of an apparatus for stereotactic mammography is described. The commercial modality of the apparatus described and illustrated in said patent has been used to guide a biopsy needle in a region of interest to obtain cell and tissue samples. Likewise, said device has been used to guide the surgical instruments of rotary cutting, to remove tissue from a region of interest. As described in the publication of C.W. Putnam, "Techniques of Ultrasonic Dissection in Resection of the Liver", Surgery. Gynecology & Obstetrics. Vol. 157, pages 474 to 478, November 1983, the ultrasonic aspiration dissectors, such as the Cavitron Ultrasonic Surgery Aspirator, comprise a manual piece, which is connected to a control console. The handpiece contains a magnetostrictive water-cooled transducer, which activates a hollow titanium tip along its longitudinal axis at a frequency of approximately 23,000 cycles per second. The tip of the handpiece is irrigated and a suction line is connected to the hollow tip to suck irrigating blood and tissue fragments. The instruments work generating ultrasonic vibrations, which selectively fracture the tissue in proportion to its water content. The fractured tissue is removed, through the suction line. Normally, said ultrasonic aspirators for surgery are manually controlled in an open surgery procedure, which is not invasive in the least. However, as suggested by the above reference article, said apparatuses are used because they provide a great differentiation between the different types of tissue structure found during a surgical procedure, comprising for example, a liver. Until now, it is not believed that an ultrasonic surgical aspirator is generally used as a slightly invasive tool to remove tissue from a region of interest in a patient's body, such as a breast, or that said tool is guided by an apparatus. of stereotactic radiography, to remove tissue from the region of interest.

SUMMARY OF THE INVENTION Therefore, it is a principal object of the present invention to guide a tool for removing ultrasonic aspiration tissue for surgery to a region of interest within a part of a patient's body. It is another object of the present invention to guide and control a tool for removing tissue, within a volume surrounding a region of interest within a part of a patient's body.

These objects are achieved, at least in part, by providing a method and apparatus for removing tissue from a volume surrounding a region of interest within a part of a patient's body. The apparatus comprises a fastener for the body part, adapted to hold the immobile part of the body. It also defines a previously determined reference point, relative to the immobile body part. The apparatus employs a stereotactic image generation assembly, having a radiation transmission source adapted to receive operating instruction signals and to irradiate the body part, and a radiation receiver adapted to transmit signals of the image corresponding to the radiation received from the source of transmission that passes through a part of the body, to obtain stereotactic images of a part of the subject body and the region of interest thereof. The apparatus includes a screen adapted to receive signals and to display stereotactic images of a part of the body and the region of interest thereof, corresponding to the signals received on the screen. An interface for the user, adapted to interactively enable a user to place a boundary around the region of interest of a body part shown, provides boundary signals that represent the dimensions and location thereof around the region of interest . The apparatus also includes a motorized guide passage for the tissue removal tool that has the ability to move relative to the previously determined reference point. The guide passage of the removal tool is adapted to receive operating signals, to drive the passage to a position relative to the previously determined reference point and is further adapted to provide signals indicating position, to indicate the position of the passage relative to the previously determined reference point. A tool to remove tissue is held by the tool guide step. The tool for removing tissue has a fragmentation tip and a means for extracting or removing the fragmented tissue from the fragmentation tip. The apparatus is directed by a controller adapted to: provide operating signals to the radiation source to cause the radiation source to transmit radiation; receive signals from the image of the radiation receiver; provide screen signals to the screen based on the signals of the received image; receive signals from the limit of the user interface; provide screen signals from the limit to the screen based on the limit signals received; calculating the size and location of a tissue removal volume, relative to the operating signals provided to the motorized guide passage, to command the passage to move to a position within the calculated volume of tissue removal; and receive the signals indicating the position, coming from the guide step. The method of the present invention comprises several steps including; the securing of a part of a patient's body, which has a region of interest therein, relative to a previously determined reference point; the obtaining of stereotactic images of a part of the body that contains in it the region of interest; and showing the stereotactic images. Once the stereotactic images are shown, the method comprises the following additional steps: placing a boundary around the region of interest in each stereotactic image shown; determining the size and location of a tissue removal volume surrounding the region of interest relative to the previously determined reference point from the location, dimensions and relative geometry of the boundaries; holding a tip of a tool to remove tissue relative to the previously determined reference point; and the movement of the tip of the tool to remove tissue within the tissue removal volume to remove tissue from within the tissue removal volume. Other objects and advantages of the present invention will be appreciated by those skilled in the art from reading the detailed description, in conjunction with the drawings and claims appended thereto.BRIEF DESCRIPTION OF THE DRAWINGS The drawings, which are not drawn to scale, include: Figure 1 is a schematic diagram of the apparatus for removing tissue and for monitoring the method of tissue removal; Figure 2 is a side view of an apparatus with a biopsy needle for stereotactic mammography to guide and control a tool for removing tissue by ultrasonic suction for surgery, according to the method of the present invention; Figure 3 is a perspective view of an ultrasonic suction apparatus. Figures 4A, 4B and 4C, are side, front views and from the top of the vacuum cleaner and the passage; Figures 5A and 5B, are schematic illustrations of the aspirator and the passage swinging around a swing point; Figure 6 is a flow chart of the method of the present invention; Figures 7A and 7B are planar views of left and right stereotactic images of a breast containing the region of interest; Figure 8 is a combined perspective view of the geometric relationship of the boundaries drawn around the region of interest, shown in the stereotactic images; Figure 9 is a plan view of the geometric relationship of the boundaries drawn around the region of interest and further illustrating the derivation of the tissue removal volume; and Figure 10 is a third dimension trace of the sensor indications against the position of the tool for elimination, in terms of Cartesian coordinates.

Detailed Description of the Invention The present invention relates to a method and apparatus for removing tissue from a volume surrounding a region of interest in a part of the body. Although the present invention will be discussed in the context of a suspicious lesion contained within a breast, which has been previously diagnosed by the procedures of a mammographic biopsy, those skilled in the art will appreciate that the present invention can be used elsewhere in the art. body containing regions of interest in which there is tissue to be removed. The apparatus of the present invention will be discussed first and then the method thereof will be discussed.

The Apparatus With reference to Figure 1, the apparatus for removing tissue from a volume surrounding a region of interest within a part of a patient's body is composed of several components. The apparatus 10 includes a fastener of a part of the body 12, adapted to hold a part of the immobile body 14, such as a breast, and to define a predetermined reference point. It also includes a stereotactic image generation assembly, having a radiation transmission source 16, adapted to receive operation command signals and to radiate the body part 14, and a radiation receiver 18 adapted to transmit image signals. corresponding to the radiation received from the transmission source 16, which passes through a part of the body 14. The image generation assembly is further adapted to obtain stereotactic images of a part of the body 14, held by the fastener 12 and the region of interest in it. The apparatus also includes a screen 24, which is adapted to receive screen signals and to display stereotactic images of a part of the body 14 and of the region of interest therein corresponding to the received screen signals. The screen 24 may be an ordinary video screen having adequate contrast and resolution capability to allow visualization of the region of interest within a body part. The apparatus is further provided with an interface for the user 26, which is adapted to enable the user to interactively provide a visible boundary around the region of interest in the body part 14 shown in each stereotactic image. This interface can be, for example, a keyboard, a mouse, a spherical control, which interfaces with the control software. The interface also makes possible a limit signal representing the dimensions and position of the visible limit that will be formed by each limit, which, as will be described below, is used to calculate a tissue removal volume.

The apparatus further includes a motorized guide passage of the tissue removal tool 28, which has the ability to move relative to the predetermined reference point previously defined by the fastener 12. The removal tool is adapted to receive operating signals for driving step 28 to one or more positions relative to the previously determined reference point. The passage is also adapted to provide signals indicating position, to indicate the position of the passage relative to the predetermined reference point defined previously by the fastener 12. The tool for removing tissue 30 is held by the tool guide passage 28, Preferably, the tool for removing tissue has a fragmentation tip 32 and a conduit 34, for removing or removing the fragmented tissue from the fragmentation tip 32. The components of the apparatus described above are controlled by a controller 36, which may be formed by any computer available in the market, that has a sufficient processing speed and memory, such as a computer that has an Intel Pentium II ™ processor that operates at 300 Mhz with 64 Mbytes of RAM. The controller 36 is adapted to coordinate a number of functions of the apparatus including: providing operation signals to the radiation source 16, to cause the radiation source to transmit radiation; receiving the signals from the image of the radiation receiver 18; providing screen signals to the screen 24 based on the signals of the received image; receive the signals of the conformal limit are created by the user interface; providing limit screen signals to the screen 24 based on the received border signals; calculating the size and location of a tissue removal volume, relative to the predetermined reference point previously defined by the fastener 12 based on the received limit signals. The controller also provides signals to the motorized guide passage 28, to command the passage to move to a position within the calculated volume of tissue removal, and receives the signals indicating the position of the guide passage 28. A more advanced embodiment of the present invention includes a removed tissue sensor 38 connected to the conduit 34 of the tool for removing tissue. The extracted tissue is passed through the tissue sensor through the conduit 34. The tissue sensor 38 is adapted to sense whether the removed tissue contains a detectable labeling substance which has been injected into the body part with the intention of marking the tissue in the region of interest, with the detectable labeling substance. The removed tissue sensor is further adapted to provide perception signals to the controller 36 and this in turn is suitably adapted to receive said tissue sensor signals. Therefore, assuming that the region of interest is composed of cancerous tissue, the tissue removed from the region of interest must cause the sensor 38 to indicate that the tissue was in the region of interest due to the high concentration of radioactive isotopes that they are present in the removed tissue. Assuming that the tissue around the region of interest is not cancerous and that there is therefore no concentration or there is a low concentration of radioactive isotopes, the material removed around the region of interest, but outside of it, normally, if the The sensor threshold is calibrated correctly, it will not be perceived by the tissue sensor 38. The apparatus can be provided with a magnetic data storage apparatus 37, which can store the signals generated by the tissue sensor and by the signals that indicate the position of step 28. The data can be retrieved from the storage apparatus 37 by the controller, to form and display a map of the tissue sensor signal against the signal indicating the position. Figure 2, illustrates an inclined apparatus for stereotactic mammography, which is normally used during breast biopsies with needles guided by stereotactic mammography, and which can be used with the present invention. In U.S. Patent No. 5,289,520, which is incorporated herein by reference, a detailed description of the slanted stereotactic apparatus 10 can be found. The SteroGuide ™ stereotactic mammography apparatus, which is commercially available from Trex Medical Corporation, is an apparatus that operates under the configurations and principles described in U.S. Patent No. 5,289,520. Generally, the stereotactic apparatus illustrated in Figure 1 has a stereotactic image generation assembly comprising an x-ray tube 16 and an image receiver 18, mounted on an image generation arm 42 having the ability to move in relative shape to the chest, to provide two stereotactic images. The apparatus has a fastener 12 for holding the chest motionless and compressed. More specifically, the fastener 12 comprises a movable compression blade 44 and a movable compression plate 46, and these define a predetermined reference point around the chest 14. In the present invention, the configuration of the stereotactic apparatus illustrated in FIG. Figure 1, due to the advantages of image acquisition resulting from the relative configuration of the image generation arm and the compression arm. In U.S. Patent No. 5,289,250 and in U.S. Patent No. 5,594,796, which are incorporated herein by reference, such a convenient configuration is described. However, other devices for stereotactic mammography biopsy can also be used, including both vertical and inclined ones, which use other configurations of image generation and compression. An example of such other configurations can be found in US Patent No. 4,727,565 to Ericson. titled "Location Method". The stereotactic apparatus 10 illustrated in Figure 1 contains a motorized guide passage 28, which can be adapted for the purposes of the present invention. Normally the step is used to guide an instrument with a biopsy needle or a rotary cutting tool, held in the holder 48, which is adapted to hold said devices correctly. Therefore, the fastener can be modified for the present invention, as required, to hold a tool for removing tissue by ultrasonic aspiration for surgery, in a manner in which the tip of said tool can be guided to a region of interest. within a chest presented in pendulous form in the stereotactic apparatus, as illustrated. As will be described later, in the case of the tool with ultrasonic suction illustrated in Figure 3, the fastener needs to be manufactured so as not to interfere with the operation of the tool. Figure 3 illustrates a tool for removing tissue with ultrasonic aspiration 50, manufactured by Valleylab, Inc., and marketed under the CUS ™ trademark. The tool comprises a transducer 52 surrounded by an electric coil 54. The coil causes the transducer and the tip 32 thereof to vibrate at ultrasonic frequencies. The tool also includes an irrigation duct 58, for providing irrigation at the tip 32 and in the suction duct 34, which provides a suction source for removing tissue fragments located at or near the tip 32. As described above, the conduit 34 may be connected to the tissue sensor 38. The tissue removed in the conduit 34 may pass through the sensor to determine if the tissue removed is from the region of interest, such as tissue containing a marking substance. which can be detected by the sensor. However, in the present invention the tool for removing tissue aspirated by ultrasound CUSA ™ has already been mentioned., those skilled in the art will appreciate that other configurations of tissue removal tools aspirated by ultrasound, also work well for the purposes of the present invention. Likewise, those skilled in the art will also appreciate that other types of tools for removing tissue may also be employed in the present invention. Figures 4A, 4B and 4C are schematic side, front and top views of the aspirator and the passage illustrating the directions X, Y and Z of the orthogonal movement of the passage 38 and of the tool for removing tissue aspirated by ultrasound 30. Figures 5A and 5B show that step 28 can be further balanced, if desired, around a swing point 60 of the arbitrarily selected vacuum cleaner.

The Method The method for removing tissue from a volume surrounding a region of interest within a part of the body of a patient comprising several steps, which will be described further below, with reference generally to Figure 6. In the method 100, the first step (step 102), is to hold a part of a patient's body, which has a region of interest therein. Said clamping also establishes a reference point previously determined for the apparatus. The next step (step 104) in the method is to obtain stereotactic images of a part of the body 14 that contains the region of interest 15 within it. This step is performed in an ordinary manner, for example, as described in US Patent No. 5,289,520. Once the images are obtained, they are shown (step 106), as illustrated in Figures 7A and 7B together with the reference point 17. As illustrated further in Figures 6, 7A and 7B, a limit 62a, 62b is placed interactively (step 108), through the user interface, around the region of interest 15, appearing shown in each shown stereotactic image 64a, 64b. With reference to Figures 6, 8 and 9, the controller 20 calculates the size and three-dimensional location of a tissue removal volume 66, which surrounds the region of interest 15 relative to the previously determined reference point based on the location, relative geomeand dimensions of the boundaries 62a, 62b.

The three-dimensional location of the elimination volume is calculated in an ordinary way, calculating the position of the region of interest that appears in stereotactic images relative to reference point 17, which appears in the images. A description of said calculations is provided in U.S. Patent No. 5,289,520. The dimensions of the removal volume 66 are defined by the letters a, b, c found in Figures 8 and 9. As illustrated in Figure 9, the dimensions a and b are derived by drawing a rectangular perimeter around the crossed diagonals formed by the boundaries 62a, 62b, when the perspective view of Figure 8, is observed from above as in Figure 9. The dimensions a and b, will vary according to the dimensions of the boundaries 62a, 62b, drawn around the region of interest and the angle (alpha) used for the generation of stereotactic images. The dimension c is the height of the limits, which will vary according to the dimensions of the boundaries drawn around the region of interest. The method preferably assumes that the dimensions of the boundaries 62a, 62b, placed on the regions of interest in the respective stereotactic images, are the same. This will have the effect of simplifying and speeding up the calculations. However, for the purpose of the present invention, no such assumption is required at all. Likewise, the limits 62a, 62b have been illustrated as squares. However, it will now be appreciated by those skilled in the art that the boundaries 62a, 62b need not be square in shape, they may be, for example, rectangular, circular or elliptical, and, therefore, the shape of the calculated removal volume. , it will change since its dimensions and shape are directed by the dimensions and shape of the boundaries 62a, 62b. As illustrated in Figure 6, the next step (step 1 10) is to hold a tip of a tool to remove tissue, relative to the previously determined reference point and said step is followed by movement of the tool point to remove tissue (step 1 12), within the tissue removal volume 66, to remove tissue from within the tissue removal volume. If desired, the tissue in the region of interest can be labeled with a radioactive isotope and the removal of said tissue can be monitored (step 14), to develop a three-dimensional map of the tissue removal process, against the coordinates of the tip of the tool to remove tissue, which is derived from the knowledge of the position of the tip relative to the guide step and the position of the step as guide. In Figure 10, an example map 70 of said step is illustrated. A three-dimensional pattern 72 is illustrated, against the orthogonal coordinates of the tip of the tool for removing tissue. The pattern is comprised of a plurality of points indicating that the tissue sensor detected marked tissue or did not detect marked tissue. The pattern provides an image of the results of the tissue removal procedure.

Therefore it will be noted that the objects and advantages established and appreciated from the above descriptions are efficiently achieved and, since certain changes can be made in the previous construction without departing from the scope of the present invention, it is intended that the Matter contained in the previous description or shown in the accompanying drawings, is interpreted in an illustrative sense and not limitation. It should also be clear that the following Claims are intended to cover all the generic and specific features described herein of the present invention, and that all manifestations of the scope of the present invention, which, as a matter of language, may be mentioned to be within Of the same.

Claims (11)

R E I V I N D I C A C I O N S Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property.

1. A method for removing tissue from a volume surrounding a region of interest within a part of the body of a patient, said method comprising the steps of: securing a part of the body of a patient having a region of interest therein, relative to a previously determined reference point; obtain stereotactic images of a part of the body that contains the region of interest in it; show the stereotactic images; place a boundary around the region of interest in each stereotactic image shown; determining the dimensions and location of a tissue removal volume surrounding the region of interest, relative to the previously determined reference point from the location, dimensions and relative geometry of the boundaries; hold a tip of a tool to remove tissue, relative to the previously determined reference point; and moving the tip of the tool to remove tissue within the volume for tissue removal, to remove tissue from within the tissue removal volume.

2. The method as described in Claim 1, further characterized in that it comprises the steps of: injecting a substance into a part of the body, to mark the tissue that is in the region of interest; and sensing the tissue removed with the tissue removal tool, to determine if the tissue being removed from the tissue removal volume is tissue marked from the region of interest.

3. The method as described in Claim 2, further characterized in that it comprises the steps of: recording the perception of the marked region against the position of the tip of the tool for removing tissue, which lies within the tissue removal volume .

4. The method as described in Claim 3, further characterized by comprising the step of displaying the record.

5. The method as described in Claim 4, further characterized in that screen display is performed when the tip of the tissue removal tool has moved completely within the tissue removal volume.

6. An apparatus for removing tissue from a volume surrounding a region of interest within a part of the body of a patient, said apparatus comprising: a fastener of the body part, adapted to hold the immobile body part and define a reference point previously determined around the immobile body part; a stereotactic image generating assembly having a radiation transmission source, adapted to receive operating instruction signals and to irradiate the body part, and a radiation receiver adapted to transmit image signals corresponding to the radiation received from the source of transmission passing through the body part, the assembly being further adapted to obtain stereotactic images of the subject body part and the region of interest therein; a screen adapted to receive screen signals and to display stereotactic images of the part of the body and the region of interest within it, corresponding to the received screen signals; an interface for the user, adapted to enable the user to place interactively, a visible boundary around the region of interest of the body part shown in each stereotactic image, and to provide boundary signals representing the location and dimensions of each one of the limits; a motorized guide passage of the tool for removing tissue, which has the ability to move relative to the previously determined reference point, the tool being adapted for elimination, to receive operating signals to drive the passage to a position relative to the point of reference previously determined and being further adapted to provide indication signals indicating the position of the passage relative to the previously determined reference point; a tool for removing tissue, held by the guide passage, further having the tool for removing tissue, a fragmentation tip and a means for removing fragmented tissue from the fragmentation tip; and a controller adapted to: provide operating signals to the radiation source, to cause the radiation source to transmit the radiation, to receive signals from the radiation receiver image, to provide screen signals to the screen, based on the signals of the received image, receive signals from the limit of the user interface, provide screen signals from the limit to the screen, based on the received limit signals, calculate the size and location of a tissue removal volume, in relative form to the previously determined reference point, based on the received limit signals, to provide operating signals to the motorized guide passage, to command the passage to move to a position within the calculated volume of tissue removal, and to receive signals indicating the position of the guide step.

7. The apparatus as described in Claim 6, further characterized in that the apparatus further comprises a tissue removal sensor connected to the tool means for removing tissue during the removal of tissue from the tip, where the tissue sensor is located. adapted to sense whether the removed tissue contains a marking substance, wherein the removed tissue sensor is further adapted to provide perception signals to the controller, and wherein the controller is additionally adapted to receive the sensing signals from the tissue sensor.

8. The apparatus as described in Claim 7, further characterized in that the apparatus further comprises a data storage apparatus and wherein the controller is further adapted to store the perception signals and the signals indicating the position of the passage in the data storage device.

9. The apparatus as described in Claim 8, further characterized in that the controller is further adapted to recover the perceived signals and signals indicating the passage position of the data storage apparatus, and to provide signals from the map to the screen, to show a map of the signals perceived against the signals indicating the position of the step.

10. The apparatus as described in Claim 6, further characterized in that the tool for removing tissue is an ultrasonic surgical suction apparatus.

11. An apparatus for removing tissue from a volume surrounding a region of interest a part of the body of a patient, said apparatus comprising: means for holding a part of a patient's body that has , a region of interest therein, relative to the previously determined reference point; means for obtaining stereotactic images of the region of interest within the body part; means for displaying stereotactic images; means for placing a boundary around the region of interest in each of the stereotactic images shown; means for determining the size and location of a tissue removal volume around the region of interest, relative to the previously determined limit reference point; a tool to remove tissue that has a tip; means for holding the tip of the tool to remove tissue, relative to the previously determined reference point; and means for moving the tip of the tool to remove tissue, relative to the tissue removal tool and within the predetermined tissue removal volume, to remove tissue from within the tissue removal volume.