WO2011083412A1

WO2011083412A1 - Biopsy planning

Info

Publication number: WO2011083412A1
Application number: PCT/IB2011/050007
Authority: WO
Inventors: Holger Timinger; Ingrid Schulze-Wenck
Original assignee: Koninklijke Philips Electronics N.V.; Philips Intellectual Property & Standards Gmbh
Priority date: 2010-01-07
Filing date: 2011-01-04
Publication date: 2011-07-14

Abstract

Into an advanced biopsy planning illustration, additional means are integrated, which allow for needle manipulation and visualization of the resulting arrangement. The illustration, together with the possibility of moving the needle up and down, helps the operator to plan the biopsy, to identify potential risks (needle hits detector), and in total, to speed up the procedure, which is great benefit for the patient (feels more comfortable) and the operator (saves time and money).

Description

BIOPSY PLANNING

FIELD OF THE INVENTION

The invention relates to the field of biopsy. Particularly, the invention relates to a method and system for planning a biopsy. Furthermore, the invention relates to a computer program for performing the method.

BACKGROUND OF THE INVENTION

In the state-of-the-art stereotactic-guided biopsy for example in mammography, the optimal biopsy needle position is calculated based on operator input. The operator marks the target tissue in the two stereotactic images (typically acquired at ± 15° tube arm angulation). Using this knowledge and the known imaging geometry, the position of the target tissue can be calculated in three-dimensional space. The needle is then positioned according to this determined position. If the operator wants to position the needle differently, he or she can modify the needle position only at the stereotactic needle holder hardware.

If the correction of the needle location, however, is done directly at the needle holder hardware, the operator does not see the influence of the modification on the total arrangement. Additionally, the operator can not simulate different scenarios, but has to perform the modification without visual feedback.

US 2008/0198966 Al relates to three-dimensional imaging of a breast tissue, which is achieved by acquiring a series of X-ray projection images from various angles. A three-dimensional image constructed from the projection images by a computer provides information to the operator to select a coordinate point within the breast from which to obtain a biopsy sample. Acquisition of projection images and construction of three-dimensional images is continued during the insertion of the needle into the breast, during positioning the needle towards the coordinate point, during the sampling and after the sampling. However, by generating three-dimensional images before, during and after the positioning of the biopsy device, the tissue is subjected to a lot of radiation. SUMMARY OF THE INVENTION

It is an object of the invention to provide a method and system for planning a biopsy to reduce the radiation which is necessary during the actual biopsy. Another object of invention is to provide a method and system for a biopsy by means of which an identified target will be reliably extracted.

This is achieved by the subject-matter of each of the independent claims. Further embodiments are described in the respective dependent claims.

Into an advanced biopsy planning illustration, additional means are integrated, which allow for needle manipulation and visualization of the resulting arrangement. The illustration, together with the possibility of moving the needle (up and down), helps the operator to plan the biopsy, to identify potential risks (needle hits a boundary), and in total, to speed up the procedure, which is great benefit for the patient (feels more comfortable) and the operator (saves time and money).

In general, a method of planning a biopsy of an identified target according to the invention comprises the steps of determining the optimal position of a biopsy device, visualizing schematically the biopsy device together with the target, checking if the position is critical, modifying the position of the biopsy device when the position is classified as critical, and generating parameter for a biopsy.

It is pointed out that each of the steps of the method according to the invention are performed during planning of a biopsy, i.e. not during the biopsy itself, i.e. the extraction of tissue. The method helps to find the shortest possible path for the biopsy device to reach the target region within the tissue.

In the context of the invention, the optimal position is a position in which the opening of the biopsy device provided to accommodate a target tissue to be extracted, is located such that the target tissue is positioned in the middle of the opening of the biopsy device. Since the biopsy device will push the tissue to the side during insertion of the biopsy device, a target tissue may be most reliably extracted if the target tissue has the chance to elastically return into the opening of the biopsy device. Therefore, an operator may usually try to position a biopsy device such that a target tissue is located at this optimal position.

However, the position of a biopsy device may be classified as critical, for example, if a tip of a biopsy device is located very close to a boundary surrounding the tissue including the target. Such a boundary may be a blood vessel, an organ, bone, or the skin at the opposite side of the point of insertion of the biopsy device. Therefore, the tip of the biopsy device may unintendedly damage structures within a body. For example, in case of a mammography, in which the skin of the breast is located directly on a detector plate, it can be considered as critical if the biopsy device may hit the detector plate.

The parameters, which will be generated by the method according to the invention may be first of all the point of insertion of the biopsy device, but also the spatial orientation of the biopsy device, i.e. the angles relative to for example the vertical and horizontal directions, as well as the depth of insertion of the biopsy device. Usually, the point of insertion will represent a reference point and coordinate system and the position of the target inside the tissue may be calculated relative to this reference point.

Accordingly, the position of the biopsy device includes a spatial orientation and a depth of insertion of the biopsy device. Furthermore the step of modifying may include a moving of the biopsy device in an axial direction thereof. Additionally or alternatively, the biopsy device may be moved in a lateral direction to modify the position of the biopsy device relative to the target. To find the best or shortest possible path for the biopsy device to reach the target region within the tissue, the point of insertion, the spatial angles as well as the depth of insertion may be modified, during the planning of the biopsy.

In case a biopsy device is already inserted into tissue it will be possible to move the biopsy device substantiall in an axial direction thereof, changing the angular orientation of the biopsy device may only be possible to a limited degree. Since an angular modification of the orientation of the biopsy device may cause any insurance or unintended damage in the tissue, it is usually preferred to move the biopsy device along its axial direction.

Having a target as well as boundaries identified, the steps of the method may be performed substantially automatically. However, the step of modifying will usually be performed manually, since it may depend on the knowledge of an operator how far the biopsy device should be moved in its axial direction. In case an operator realizes a critical position of a biopsy device, he or she has to decide for example how far the biopsy device should be retracted or, in other words, how deep the biopsy device should be inserted without reaching the optimal position. Since this estimation is different in any case of biopsy, this step of the method according to the invention may hardly be performed automatically.

A further step of the method according to the invention may be the receiving of an image including the target, wherein such image may be an X-ray image or a series of X-ray images allowing a three-dimensional determination of the position of the target.

For the planning of the biopsy, it is only necessary to visualize a position of a target together with relevant boundaries to estimate parameters for a biopsy. However, it may also be possible to visualize an overlay of an X-ray image together with the target and boundaries, to provide for a better overview of the tissue surrounding the target of the biopsy.

According to another aspect of the method according to the invention, the method may further comprise the step of indicating a position as critical. This may be achieved by highlighting the schematically illustrated biopsy device in the planning scenario. For example, the colour of the biopsy device may be changed in the visualization or may blink or may be shown brighter than usual. Furthermore, it may be possible to show a word like 'danger' or 'critical' or the like, to advise an operator of the critical position.

According to another embodiment of the invention, a system for planning a biopsy is provided, wherein the system comprises substantially a processing unit, a monitor and a computer program, wherein the computer program includes sets of instructions for each of the steps of the method according to the invention, and wherein the computer program, of course, is adapted to be executed on the processing unit.

The system according to the invention may further comprise an imaging device like an X-ray system, for generating an image including a target. The processing unit of the system may be connected with the imaging device to directly receive an image showing tissue including a portion or area which should be subjected to a biopsy.

It is noted that the system according to the invention may also be connected to a network and the image which forms the basis for the planning of the biopsy may be received over that network. In case the system is directly connected to an imaging device the planning of a biopsy may be performed directly after the generation of an image.

The biopsy device of the system according to the invention may comprise a biopsy needle and means for holding the biopsy needle in a defined spatial orientation, and may further comprise means for moving the biopsy needle in an axial direction thereof. With such means it may be possible to perform a biopsy based on the parameters which result from the method according to the invention. The biopsy needle may be in a first step positioned as estimated by the method in a spatial orientation at a point of insertion. Subsequently, by moving the biopsy needle in axial direction, the biopsy needle will be inserted into the tissue to the depth at which the biopsy may be taken. The means for moving the biopsy device may also provide for the possibility to move the biopsy device in a lateral direction, or to vary one or more spatial angles, to correct the path to a certain degree when the biopsy device is already inserted into a body.

The tissue which may be extracted by the system may comprise all kind of living or dead tissue, e.g. human tissue, particularly epithelium-tissue (e.g. surface of the skin and inner lining of digestive tract), connective tissue (e.g. blood, bone tissue), muscle tissue and nervous tissue (e.g. brain, spinal cord and peripheral nervous system). Additionally, tissue may further comprise food products, biomaterials, synthetic materials, fluid or viscous substances, etc.

It is noted that the biopsy device may include a biopsy needle, a canula or a trocar or might also be a catheter adapted to receive a needle by which for example a biopsy will be actually performed.

According to a further embodiment of the invention, a computer program for planning a biopsy of an identified target is provided which when executed on a processing device of an appropriate system, causing the system to perform the method according to the invention. Therefore, the method according to the invention may be performed substantially automatically, or at least predominantly automatically. Therefore, the computer program may comprise sets of instructions for determining an optimal position of a biopsy device on the basis of identified target and identified boundaries, sets of instructions for visualizing schematically the biopsy device together with the target, sets of instructions for checking if the position is critical, sets of instructions for modifying the position of the biopsy device when the position is classified as critical, and sets of instructions for generating parameter for a biopsy on the basis of the modified position.

Such a computer program is preferably loaded into a work memory of a data processor. The data processor or processing unit is thus equipped to carry out the method of the invention. Further, the invention relates to a computer-readable medium such as a CD- ROM at which the computer program may be stored. However, the computer program may also be presented over a network like the World Wide Web and can be downloaded into the working memory of the data processor from such a network.

It has to be noted that embodiments of the invention are described with reference to different subject-matters. In particular, some embodiments are described with reference to method type claims whereas other embodiments are described with reference to apparatus type claims. However, a person skilled in the art will gather from the above and the following description that unless other notified in addition to any combination of features belonging to one type of subject-matter also any combination between features relating to different subject-matters is considered to be disclosed with this application.

The aspects defined above and further aspects, features and advantages of the present invention can also be derived from the examples of the embodiments to be described hereinafter and are explained with reference to examples of embodiments also shown in the figures, but to which the invention is not limited.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows an example of a system according to the invention.

Fig. 2 shows a visualization of a biopsy device in a critical position.

Fig. 3 shows a biopsy device retracted from the critical position of Fig. 2. Fig. 4 shows a flow-chart of a method according to the invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

Fig. 1 shows an exemplary embodiment of a system according to the invention. Substantially, necessary for performing the method according to the invention, a processing unit 420 together with a monitor 440 of a computer 400 is part of the system. Further, the system comprises a biopsy device 100, an imaging device 200, and a control device 300.

The biopsy device 100 includes a biopsy needle 120 as well as an actuator 140 for moving the biopsy needle 120 substantially in its axial direction. The actuator 140 may be arranged so that the biopsy needle together with the actuator is positioned in a defined spatial orientation.

The exemplary imaging device 200 includes an X-ray source 240, an X-ray detector 260, wherein these two devices are mounted on a C-arm 220. It will be understood that the system in accordance with the invention may also comprise a non-invasive imaging modality like a computer tomography device, a magnetic resonance device, or an ultrasound device as imaging device instead of or additional to the shown C-arm based X-ray device.

The biopsy device 100 as well as the imaging device 200 are connected to the control device 300 which control device includes a first control unit 320 for controlling the position and movements of the C-arm 220 as well as the imaging by means of the source and detector, and a second control unit 340 for controlling the actuator 140 and thus the movement of the biopsy needle 120.

The control device 300 may be connected with the computer 400 by a data connection line 460. The data connection line 460 may be utilized in a first step to transmit an image from the imaging device to the computer, i.e. to the processing unit 420 of the computer 400. After performing the method according to the invention on the computer 400, the data connection line 460 may then be utilized to transmit parameter for the spatial orientation and the depth of insertion to the control device 300 for controlling the actuator and for actually performing the biopsy. Also shown in Fig. 1 is an object including a target 500 which is subjected to the biopsy.

Fig. 2 shows a biopsy needle 120 of a biopsy device including a tip 160 as well as an opening 180 for receiving tissue of a target 500, wherein the biopsy needle 120 is located in an optimal position with respect to the target. That is, the biopsy needle 120 is in a first approach positioned, such that the tissue of the target 500 is located in the middle of the opening 180. However, in this optimal position, the tip 160 of the biopsy needle 120 is located near a boundary 520. In other words, the tip 160 of the biopsy needle 120 is not sufficiently far away from the boundary, including the risk of unintended damage or injury.

Realizing or classifying the position of the biopsy needle 120 as critical, an operator may wish to modify the position of the biopsy device by retracting the needle device. To have the possibility of modifying the position of the biopsy needle, a planning tool as shown in the Figs. 2 and 3 is provided, including buttons 480, 490 with arrows up and down. Thus, an operator may push one of the buttons, in this case the upper button 480 to virtually move the biopsy needle 120 away from the boundary, i.e. to modify the position of the biopsy needle to a better position.

As shown in Fig. 3, the biopsy needle 120 is now sufficiently away from the boundary 520, wherein the tissue of the target 500 is yet located within the opening 180 of the biopsy needle 120. During modifying of the needle, an operator has to balance the distance of the tip 160 of the needle device 120 and the actual position of the tissue of the target 500 within the opening 180, since having the tissue of the target 500 out of center of the opening 180 may reduce the chance of extracting the intended tissue.

Beside the visualization of a biopsy needle, a target and boundaries, further information like the current target position or the orientation and depth of the needle device may be shown in the visualization. Additionally, any other suitable information may be included in the visualization.

The flow-chart in Fig. 4 illustrates the principle of the planning of a biopsy according to the invention. It will be understood that the steps described with respect to the method are major steps, wherein these major steps might be differentiated or divided into several sub-steps. Furthermore, there might be also sub-steps between these major steps. Therefore, a sub-step is only mentioned if that step may be important for the understanding of the principles of the method according to the invention. In step SI, an image or a plurality of images for a three-dimensional visualization is received. This step may also include the identification of a target and the identification of boundaries, wherein the boundaries surround the tissue within which the target is located.

In step S2, an optimal position of a biopsy device is determined. This step may include several approaches with different spatial orientations and different depths of introduction of a biopsy needle.

In step S3, a chosen optimal position of a biopsy device will be schematically visualized. This step may include the overlay of the schematically visualized biopsy needle together with the target, by an image forming the basis of the identification of the target.

In step S4, the position which is considered as optimal for taking a biopsy, is examined and classified. As a result of the examination, the optimal position may be classified as critical. In case the position is classified as critical, this result may be indicated in the visualization by changing the colour of the biopsy device or introducing a word or a flashing button.

In step S5, an operator may have the possibility to modify the position of the biopsy needle by the buttons for modifying the position.

On the basis of the modified position, the processing device will generate the parameters for an actual biopsy in step S6.

On the basis of the generated parameters, a biopsy may be performed subsequently.

While the invention has been illustrated and described in detail in the drawings and afore-going description, such illustrations and descriptions are to be considered illustrative or exemplary and not restrictive, the invention is not limited to the disclosed embodiments.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practising the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may fulfil the functions of several items recited in the claims.

The mere fact that certain measures are recited and mutually different dependent claims does not indicate that a combination of these measures can not be used to advantage. A computer program may be stored/distributed on a suitable medium such as an optical storage medium or a solid-state medium supplied together with or as a part of another hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. Any reference signs in the claims should not be construed as limiting the scope.

LIST OF REFERENCE SIGNS:

100 Biopsy device

120 Biopsy needle

140 Actuator

160 Tip of the biopsy needle

180 Opening of the biopsy needle

200 Imaging device

220 C-arm

240 X-ray source

260 X-ray detector

300 Control device

320 First control unit for imaging device

340 Second control unit for biopsy device

400 Computer

420 Processing unit

440 Monitor

460 Data connection line

480 Button to move needle up

490 Button to move needle down

500 Target

520 Boundary

Claims

CLAIMS:

1. A method of planning a biopsy of an identified target, the method comprises the steps of

determining the optimal position of a biopsy device (100),

visualizing schematically the biopsy device together with the target (500), checking if the position is critical,

modifying the position of the biopsy device (100) when the position is classified as critical, and

generating parameter for a biopsy.

2. The method of claim 1, wherein the position of the biopsy device (100) includes a spatial orientation and a depth of insertion of the biopsy device.

3. The method of claim 1, wherein the step of modifying includes a moving of the biopsy device (100) relative to the target.

4. The method of claim 3, wherein the biopsy device is moved in an axial direction thereof.

5. The method of claim 1, wherein the step of modifying is performed manually.

6. The method of claim 1, further comprising the step of receiving an image including the target (500).

7. The method of claim 6, further comprising the step of generating an overlay of the image and the schematical visualization.

8. Method of claim 1, further comprising the step of indicating if the position is critical.

9. A system for planning a biopsy, the system comprising a processing unit

(420), a monitor (440), and a computer program including sets of instructions for performing the steps of the method according to claim 1 , wherein the computer program is adapted to be executed on the processing unit (420).

10. The system of claim 9, further comprising an imaging device (200) for generating an image including a target (500).

11. System of claim 9, further comprising means for holding (140) a biopsy device in a defined spatial orientation.

12. The system of claim 9, further comprising means for moving (140) a biopsy device.

13. The system of claim 12, wherein the biopsy device is moved in an axial direction thereof.

14. A computer program when executed on an appropriate system, including sets of instructions for performing the steps of the method of claim 1.