WO2016091766A1

WO2016091766A1 - Supporting a user in performing an embolization procedure

Info

Publication number: WO2016091766A1
Application number: PCT/EP2015/078742
Authority: WO
Inventors: Guillaume Leopold Theodorus Frederik Hautvast; Dirk Binnekamp
Original assignee: Koninklijke Philips N.V.
Priority date: 2014-12-10
Filing date: 2015-12-07
Publication date: 2016-06-16

Abstract

The invention relates to a support apparatus (2) for supporting a user in performing an embolization procedure during which an insertion element (11) is to be inserted into a living (8) being in order to release an embolization agent for treating a target region (9) within the living being. A position tracking unit (17) tracks the position of the insertion element within the living being and a pressure determining unit (18) determines the local blood pressure at the insertion element within the living being. Based on the tracked position of the insertion element and the determined local blood pressure at the insertion element, a support information generating unit (14) generates support information which is shown to the user on a display (23). It is thus possible to provide the user with additional information that may allow him/her to more accurately release the embolization agent.

Description

Supporting a user in performing an embolization procedure

FIELD OF THE INVENTION

The invention relates to a support apparatus, a support method and a support computer program for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being. The invention relates further to a system for performing an embolization procedure comprising the support apparatus.

BACKGROUND OF THE INVENTION

An embolization procedure is a therapeutic procedure during which blood vessels are selectively occluded by introducing emboli. In a transcatheter embolization procedure, this is achieved by releasing an embolization agent: small particles that occlude blood vessels of a certain diameter for a certain amount of time. Embolization is used to treat a wide variety of conditions, relating to haemorrhage or tumor growth in different organs of a living being. In general, the purpose of embolization is to prevent blood flow to a target region, which can effectively shrink a tumor or block an aneurysm. In a radioembolization procedure, radiotherapy is delivered using an embolization agent that contains radioactive isotopes. In this process, the local blood circulation around the tumor, which is increased due to angiogenesis and lower venous blood pressure, is used to target the embolization agent and deliver radiation to the tumor. When performing the embolization procedure, it is often not easy for the user to accurately determine where the embolization agent should be released.

US 2004/0097806 Al discloses an image guided catheter navigation system for navigating a region of a patient including an imaging device, a tracking device, a controller, and a display. The imaging device generates images of the region of the patient. The tracking device tracks the location of the catheter in the region of the patient. The controller superimposes an icon representing the catheter onto the images generated from the imaging device based upon the location of the catheter. The display displays the image of the region with the catheter superimposed onto the image at the current location of the catheter. SUMMARY OF THE INVENTION

It is an object of the present invention to provide a support apparatus, a support method and a support computer program for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being, which allow the user to more accurately release the embolization agent.

In a first aspect of the present invention, a support apparatus for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being is presented, wherein the support apparatus comprises:

a position tracking unit for tracking the position of the insertion element within the living being,

a pressure determining unit for determining the local blood pressure at the insertion element within the living being,

a simulation unit for simulating which parts of the target region will be treated by the released embolization agent based on the determined local blood pressure at the insertion element,

a support information generating unit for generating support information based on the tracked position of the insertion element and the determined local blood pressure at the insertion element, wherein the support information generating unit is adapted to generate the support information such that it comprises a visual representation of the result of the simulation, and

a display for showing the support information to the user.

The distribution of the released embolization agent depends on the diameter of the blood vessel, in which it is released, at the location of release, i.e., embolization agent particles or micro-bubbles released in a blood vessel with a large diameter will usually embolize in a widespread area while particles or micro-bubbles released in a blood vessel with a small diameter will usually embolize only in a small, targeted area. Moreover, the vessel diameter is substantially proportional to the amplitude of the local blood pressure in the blood vessel, such that the dependency of diameter can also be expressed as a dependency of the local blood pressure. By generating support information that is based, in addition to the tracked position of the insertion element, also on the determined local blood pressure at the insertion element, and by showing the support information to the user, it is thus possible to provide the user with additional information that may allow him/her to more accurately release the embolization agent. In particular, by performing a simulation of which parts of the target region will be treated by the released embolization agent based on the determined local blood pressure at the insertion element and by showing the support information which comprises a visual representation of the result of the simulation to the user, it is possible to provide the user with additional information that allows him/her to more accurately determine whether he/she should release the embolization agent at the current position of the insertion element in order to achieve a desired therapeutic effect.

For instance, in an embodiment, the embolization procedure is a radioembolization procedure that is performed in order to treat a tumor in the liver of a living being. In such a scenario, if the embolization agent is released too close to the tumor, only parts of the tumor will receive (more than) the prescribed radiation dose from the released embolization agent while the remaining parts receive less radiation than intended. On the other hand, if the embolization agent is released too far away from the tumor, the entire tumor will receive only an insufficient radiation. As a result, in both cases the treatment may not be effective and local recurrences may occur. Moreover, releasing the embolization agent too far away from the tumor will result in delivering an unintended radiation dose to the surrounding tissue, which may cause undesired side effects. Thus, by performing a simulation, which, for instance, simulates which parts of the tumor will receive radiation from the released embolization agent, the user can more accurately release the embolization agent.

In an embodiment, the insertion element has a tip and an elongated body to be inserted into the living being, wherein the insertion element is adapted to release the embolization agent from its tip. In this case, the position tracking unit can be adapted to track at least the position of the tip of the insertion element within the living being and the pressure determining unit can be adapted to determine the local blood pressure at the tip of the insertion element within the living being. The insertion element can be, for instance, a catheter or a guide wire that is to be inserted into the living being through a blood vessel tree of the living being.

The living being is preferably a person or an animal, for instance, a mammal, and the target region is preferably a tissue or an organ of the living being, in particular, a tissue or an organ that shows a pathological condition, for instance, a stenosis, a tumor, or the like.

The determined local blood pressure at the insertion element can be, for instance, a local mean arterial pressure (MAP) or another pressure-based parameter that can be derived from a dynamic pressure signal, such as a local systolic pressure, a local diastolic pressure or a difference between the local systolic pressure and the local diastolic pressure (herein referred to as "pulse pressure"). The local MAP is preferably calculated as the sum of the local diastolic pressure and one-third of the pulse pressure.

It is preferred that the support information comprises a visual representation of the determined local blood pressure at the insertion element. Since the distribution of the released embolization agent depends on the local blood pressure, by showing the support information which comprises a visual representation of the determined local blood pressure at the insertion element to the user, it is possible to provide the user with additional information that may allow him/her to more accurately release the embolization agent. Moreover, the local blood pressure is anticipated to decrease as the insertion element approaches the target region, which may typically receive blood from blood vessels of smaller diameter. Thus, the visual representation of the determined local blood pressure at the insertion element may also be of help for the user in navigating the insertion element from an insertion location to the target region. Additionally or alternatively, the support information preferably comprises a visual representation of a difference between the determined local blood pressure at the insertion element and a local blood pressure at the target region. In this case, the user may know that he/she correctly navigates the insertion element from the insertion location, which may typically be at a larger blood vessel, to the target region if the values of the difference become gradually smaller as the insertion element approaches the target region.

The local blood pressure at the target region may be pre-determined, for instance, by making use of the known fact that the variation in blood pressure is mostly on the arterial side of the circulatory system. Based on this characteristic, one may use, for instance, literature values from scientific literature for pre-determining the local blood pressure at the target region. A more accurate approach would be to measure the systemic blood pressure of the living being and to derive the local blood pressure at the target region using the measured systemic blood pressure. The measurement of the systemic blood pressure can be realized using conventional arm or finger cuffs and may be performed, for instance, once at the start of the embolization procedure, or it may be monitored during the embolization procedure. Another alternative is to measure the local blood pressure at the target region using an additional local pressure sensor, which can be similar to the pressure determining unit for determining the local blood pressure at the insertion element.

The visual representation of the determined local blood pressure at the insertion element or of the difference between the determined local blood pressure at the insertion element and the local blood pressure at the target region can be, for instance, a numerical value that is shown on a suitable area of the display, a color coded graphical element that is shown together with a visual representation of the position of the insertion element, or the like. Depending on the type of the visual representation of the determined local blood pressure at the insertion element or of the difference between the determined local blood pressure at the insertion element and the local blood pressure at the target region, the visual representation can be in black and white, in grayscale or in color.

It is also preferred that the support information comprises a visual representation that indicates whether the insertion element should be positioned closer to or further away from the target region for releasing the embolization agent.

In this case, the user does not have to interpret pressure-based values, such as the determined local blood pressure at the insertion element or the difference between the determined local blood pressure at the insertion element and the local blood pressure at the target region, himself/herself when navigating the insertion element to the target region and when determining where the embolization agent should be released. Rather, he/she is provided with explicit information about where he/she should navigate the insertion element and where he/she should release the embolization agent. This may further simplify the embolization procedure. Such guidance on whether the insertion element should be navigated to a more proximal (closer) or more distal (farther away) location based on the determined local blood pressure(s) can be quite simple. If the determined blood local pressure at the insertion element is too high, the insertion element should be moved to a more distal location, if the determined local blood pressure at the insertion element is too low, the insertion element should be moved to a more proximal location.

The visual representation can be, for instance, plain textual indications, such as "closer" and "farther away", but it is also possible that the visual representation makes use of signs that are associated with certain directions. For instance, a green light may be associated with a situation in which the insertion element should be positioned closer to the target region for releasing the embolization agent whereas a red light may be associated with a situation in which the insertion element should be positioned farther away from the target region for releasing the embolization agent.

It is preferred that the support apparatus further comprises:

a live image data providing unit for providing live image data showing an inner part of the living being, which includes the target region, wherein the support information generating unit is adapted to generate the support information further based on the live image data, wherein the support information comprises a visual representation of the tracked position of the insertion element.

For instance, in an embodiment, the position tracking unit is adapted to track the position of the entire length of the insertion element, including the elongated body and the tip, within the living being and the support information generating unit is adapted to generate, as a part of the support information, overlay image data comprising the live image data with the visual representation of the entire length of the insertion element within the living being overlaid thereon. In another embodiment, the position tracking unit can be adapted to track only the position of the tip of the insertion element and the support information generating unit can be adapted to generate, as a part of the support information, overlay image data comprising the live image data with the visual representation of just the tip of the insertion element within the living being overlaid thereon.

The live image data providing unit can be, for instance, a C-arm fluoroscopy device comprising an x-ray tube for emitting x-rays that are to traverse the living being and an x-ray detector for detecting the x-rays after they have traversed the living being.

Alternatively, the live image data providing unit can be, for instance, an ultrasound device, a magnetic resonance imaging (MRI) device, or the like. The live image data preferably provide a clear and "real-time" view of the vasculature within the inner part of the living being.

The visual representation of the tracked position of the inserting element can be, for instance, a two- or three-dimensional visual representation that two- or three- dimensionally represents the shape of the insertion element at the tracked position of the insertion element or it can be a simplified visual representation that uses one or more simple graphical elements, such as a pointer, a line, a cross, or the like, for visually representing the tracked position of the insertion element. For instance, if the position tracking unit is adapted to track the position of the entire length of the insertion element, including the elongated body and the tip, within the living being, a simplified visual representation can represent the entire length of the insertion element by means of a line, and if the position tracking unit is adapted to track only the position of the tip of the insertion element, a simplified visual representation can represent the tip of the insertion element by means of a cross. Depending on the type of the visual representation of the tracked position of the insertion element, the visual representation can be in black and white, in grayscale or in color.

It is further preferred that the support apparatus further comprises: a pre-procedural image data providing unit for providing pre-procedural image data showing an inner part of the living being, which includes the target region,

wherein the support information generating unit is adapted to fuse the live image data and the pre-procedural image data to generate fused image data and to generate the support information further based on the fused image data.

By fusing the live image data, which preferably provides a clear and "realtime" view of the vasculature within the inner part of the living being, and the pre-procedural image data, which may provide, for instance, an extensive tumor characterization, and by generating the support information further based on the fused image data, the user can be provided with an information that also shows the different organs or tissues within the inner part of the living being, which includes the target region, in good detail, thereby supporting the user in navigating the insertion element to the target region and in accurately releasing the embolization agent.

The pre-procedural image data providing unit can be, for instance, a storage medium, such as a hard-disk, an optical disk or another non- volatile computer storage medium, like a flash memory, on which the pre-procedural image data is stored. Alternatively, the pre-procedural image data providing unit can be a unit that is adapted to actually generate the pre-procedural image data before the embolization procedure. For instance, the pre- procedural image data providing unit can be a computed tomography (CT) device, a magnetic resonance imaging (MRI) device, or the like. The pre-procedural image data are image data which preferably provide an extensive tumor characterization.

The visual representation of the result of the above-described simulation can be, for instance, a coloring or shading of the parts of the target region that will be treated by the released embolization agent, wherein the coloring or shading is preferably overlaid on image data showing an inner part of the living being, which includes the target region (herein referred to as "virtual release"). The image data can be, for instance, the live image data or the fused image data. Of course, instead of a coloring or shading another means for indicating the parts of the target region that will be treated by the released embolization agent can be used. For instance, the outline of these parts can be indicated by a line in the live image data or the fused image data.

The simulation unit is preferably adapted to simulate, in addition to the parts of the target region that will be treated by the released embolization agent, also the parts of the region surrounding the target region that will be affected by the released embolization agent. For instance, in the embodiment in which the embolization procedure is a radioembolization procedure that is performed in order to treat a tumor in the liver of a living being, also the parts of the liver surrounding the tumor that will receive radiation from the released embolization agent can be simulated and shown to the user in a visual representation.

The simulation may make use of blood pressure to distribution area relations, i.e., relations between the local blood pressure at the location or release of the embolization agent and the area of distribution of the released embolization agent. Such relations can be determined, for instance, during a training period, or they can be derived from experience derived from previous embolization procedures. When the local blood pressure at the insertion element is determined, the prior knowledge about the blood pressure to distribution area relations can be used to determine the affected/treated parts in relation to the tracked position of the insertion element.

It is further preferred that the support apparatus further comprises: a segmentation providing unit for providing a segmentation of blood vessels downstream of the insertion element in image data showing an inner part of the living being, which includes the target region, wherein the simulation unit is adapted to further base the simulation on the segmentation.

By further basing the simulation on a segmentation of blood vessels downstream of the insertion element, it can be simulated more accurately which parts of the target region will be treated by the released embolization agent.

The segmentation can be obtained from, for instance, a pre-procedural segmentation process that has been performed, manually or automatically, on the pre- procedural image data, or it can be obtained from a "real-time" segmentation process that is automatically performed on the image data, e.g., the live image data or the fused image data. Thus, the segmentation providing unit can be, for instance, a storage medium, such as a hard- disk, an optical disk or another non- volatile computer storage medium, like a flash memory, on which the segmentation obtained by the pre-procedural segmentation process is stored, or it can be a unit that is adapted to automatically perform the "real-time" segmentation process.

With the segmentation of the blood vessels downstream of the insertion element at hand, the simulation can be performed, for instance, using a numerical simulation of the convection flow in the vascular system, e.g., based on a finite element method or a finite difference method. The simulation preferably takes into account the determined local blood pressure at the insertion element and the diameters of the blood vessels obtained through the segmentation to determine a distribution map for the released embolization agent. This map can then be used to indicate the affected/treated parts to the user. It is preferred that the segmentation providing unit is adapted to generate the segmentation using an automatic segmentation process that is performed on the image data, wherein the automatic segmentation process is started from the tracked position of the insertion element. For instance, if the automatic segmentation process is a "real-time" segmentation process that is performed on the image data, e.g., the live image data or the fused image data, starting the automatic segmentation process from the tracked position of the insertion element makes it possible to automatically determine and segment the relevant parts of the blood vessel tree, i.e., the blood vessels downstream of the insertion element. Thus, when the insertion element is navigated to the target region, at each point during the navigation only the relevant parts of the blood vessel tree may be segmented. This may result in a simple and automatic approach to segmenting the blood vessels downstream of the insertion element.

It is preferable that the simulation is further based on the local venous blood pressure and/or on local tissue properties at the insertion element. In this case, the local venous blood pressure can be incorporated into the simulation as one of the boundary conditions of the simulation in order to determine the distribution map for the released embolization agent based on the convection flow.

It is further preferred that the embolization procedure is a radioembolization procedure and that the support apparatus further comprises:

- a dose delivery determining unit for determining a radiation dose delivered to the target region during the embolization procedure based on the simulated parts of the target region that will be treated by the released embolization agent.

In an embodiment, the position tracking unit is adapted to track the position of the insertion element by using electromagnetic tracking technology. This provides a very robust way of tracking the position of the insertion element.

In an alternative embodiment, the position tracking unit is adapted to track the position of the insertion element by using fiber optic shape sensing. For instance, optical shape sensing can be used to provide a four-dimensional tracking of the insertion element, while the insertion element is navigated to the target region. This tracking can be performed in a way which is relatively simple for the user. For instance, no further external fields like electromagnetic fields, no further radiation like further x-ray radiation, et cetera is needed for tracking the position of the insertion element within the living being. Preferably, the pressure determining unit is adapted to determine the local blood pressure at the insertion element by using fiber optic pressure sensing. Thus, the functionality of tracking the position of the insertion element and of determining the local blood pressure at the insertion element can be implemented by means of the same technology.

In a further aspect of the present invention, an embolization system for performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being is presented, wherein the embolization system comprises:

the insertion element, and

the support apparatus as defined in claim 1.

In a further aspect of the present invention, a support method for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being is presented, wherein the support method comprises:

tracking the position of the insertion element within the living being, by a position tracking unit,

determining the local blood pressure at the insertion element within the living being, by a pressure determining unit,

simulating which parts of the target region will be treated by the released embolization agent based on the determined local blood pressure at the insertion element, by a simulation unit,

generating support information based on the tracked position of the insertion element and the determined local blood pressure at the insertion element, wherein the support information is generated such that it comprises a visual representation of the result of the simulation, by a support information generating unit, and

showing the support information to the user, by a display.

In a further aspect of the present invention, a support computer program for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being is presented, wherein the support computer program comprises program code means for causing a support apparatus as defined in claim 1 to carry out the steps of the support method as defined in claim 13, when the support computer program is run on a computer controlling the support apparatus.

It shall be understood that the support apparatus of claim 1, the embolization system of claim 12, the support method of claim 13, and the support computer program of claim 14 have similar and/or identical preferred embodiments, in particular, as defined in the dependent claims.

It shall be understood that a preferred embodiment of the invention can also be any combination of the dependent claims with the respective independent claim.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

Fig. 1 shows schematically and exemplarily an embodiment of a system for performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being,

Fig. 2 shows schematically and exemplarily the blood supply of the liver of a living being,

Fig. 3 shows schematically and exemplarily the characteristics of the local blood pressure throughout the circulatory system of a living being,

Fig. 4 shows schematically and exemplarily support information for

supporting the user in performing the embolization procedure, and

Fig. 5 shows a flowchart exemplarily illustrating an embodiment of a support method for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being. DETAILED DESCRIPTION OF EMBODIMENTS

Fig. 1 shows schematically and exemplarily an embodiment of an embolization system 1 for performing an embolization procedure, here, a radioembolization procedure, during which an insertion element 11 is to be inserted into a living being 8, which, in this example, is a person, in order to release an embolization agent for treating a target region 9 within the person 8, here, a tumor in the liver 30 of the person 8. In this embodiment, the insertion element 11 is a catheter that is to be inserted into the person 8 lying on a support means 10, such as a table or the like, through a blood vessel tree of the person 8. A user, like a physician, can navigate the catheter 11 within the person 8 by using a handling unit 16. The handling unit 16 may allow the user to directly manipulate the catheter 11 or to manipulate the catheter 11 via a joystick, a graphical user interface or another means.

To provide some background, Fig. 2 shows schematically and exemplarily the blood supply of the liver 30 of the person 8. As can be seen, the liver 30 receives oxygen-rich blood through the hepatic artery 31 and nutrient-rich blood through the hepatic portal vein 32, which is supplied from the capillaries 33 of the digestive tract. In the liver 30, the supplied blood from the hepatic artery 31 and the hepatic portal vein 32 passes through the capillaries 34 of the liver 30, from where it leaves the liver 30 through the hepatic vein 35 to return to the inferior vena cava 36. It is known that the liver 30 receives 30% of its blood supply from the hepatic artery 31 and that the remaining 70% of the liver's blood supply are derived from the hepatic portal vein 32, whereas tumors in the liver 30 receive their blood supply predominantly from the hepatic artery 31 , the blood of which is more oxygen-rich. In radioembolization of tumors in the liver 30, this difference in the blood supply between the normal liver tissue and tumorous tissue is used to target the embolization agent; by releasing the embolization agent in the hepatic artery 31 , the embolization agent will be mainly distributed in the smaller blood vessels around the tumor.

With returning reference to Fig. 1, the embolization system 1 comprises a support apparatus 2 for supporting the user in performing the embolization procedure. The support apparatus 2 comprises a position tracking unit 17 for tracking the position of the catheter 11 within the person 8. In this embodiment, the position tracking unit 17 is adapted to track the position of the catheter 11 by using optical shape sensing. Thus, the catheter 11 comprises one or more optical fibers (not shown in the figures) that are adapted to allow the position tracking unit 17 to determine the position of the catheter 11 within the person 8 by using optical shape sensing. The optical shape sensing may be performed in accordance with the description in US 7,772,541 B2, or in accordance with another known optical shape sensing technique.

The support apparatus 2 further comprises a pressure determining unit 18 for determining the local blood pressure at the catheter 11 within the person 8. In this

embodiment, the pressure determining unit 18 is adapted to determine the local blood pressure at the catheter 11 by using optical pressure sensing. Thus, the one or more optical fibers comprised by the catheter 11 are further adapted to allow the pressure determining unit 17 to determine the local blood pressure at the catheter 11 within the person 8 by using optical pressure sensing. The optical pressure sensing may be performed in accordance with the description in Pinet E., Pham A., and Rioux S., "Miniature fiber optic pressure sensor for medical applications: An opportunity for intra-aortic balloon pumping (IABP) therapy", in Proceedings of 17^th International Conference on Optical Fibre Sensors, Bruges, Belgium, 2005, or in accordance with another known optical pressure sensing technique.

In this embodiment, the catheter 11 has a tip and an elongated body to be inserted into the person 8, wherein the catheter 11 is adapted to release the embolization agent from its tip. The position tracking unit 17 is adapted to track at least the position of the tip of the catheter 11 within the person 8 and the pressure determining unit 18 is adapted to determine the local blood pressure at the tip of the catheter 11 within the person 8.

The support apparatus 2 further comprises a computing device 13 with a support information generating unit 14 for generating support information based on the tracked position of the catheter 11 and the determined local blood pressure at the tip of the catheter 11. Moreover, the support apparatus 2, here, comprises an input unit 22 for allowing the user to input commands, like a start command for starting the support procedure or a stop command for stopping the support procedure, and a display 23. The input unit 22 may be a keyboard, a computer mouse, a touch screen, et cetera. The display 23 is adapted to show the support information to the user.

The determined local blood pressure at the tip of the catheter 11 may be a pressure-based parameter that can be derived from a dynamic pressure signal. For instance, as can be seen from Fig. 3, which shows schematically and exemplarily the characteristics of the local blood pressure throughout the circulatory system of the person 8, a local mean arterial pressure (MAP) 40, a local systolic pressure 41, a local diastolic pressure 42 or a difference between the local systolic pressure 41 and the local diastolic pressure 42 (herein referred to as "pulse pressure") may be usable as the basis for the support information. In the figure, the horizontal axis shows the different sections of the circulatory system from the aorta "AO" via the elastic arteries "EA", the muscular arteries "MA", the arterioles "AR", the capillaries "CA", the venules "VE", the medium-sized veins "MSV" and the large veins "LV" up to the venae cavae "VC". The vertical axis shows the local blood pressure in mm Hg (millimeters of mercury).

In this embodiment, the support apparatus 2 further comprises a live image data providing unit 3 for providing live image data showing an inner part of the person 8, which includes the tumor 9. Here, the live image data providing unit 3 is a C-arm fluoroscopy device comprising an x-ray tube 5 for emitting x-rays 6 that are to traverse the person 8. The fluoroscopy device 3 further comprises an x-ray detector 4 for detecting the x-rays 6 after they have traversed the person 8. The x-ray tube 5 and the x-ray detector 4 are mounted on a C-arm 7, which is movable with respect to the support means 10 and, thus, with respect to the person 8, in order to allow the live image data providing unit 3 to acquire live projection image data in different acquisition directions. The C-arm 7, the x-ray tube 5 and the x-ray detector 4 are controlled by a control unit 12, which is also adapted to generate the live image data based on detection values received from the x-ray detector 4. The generated live image data are two-dimensional projection image data which preferably provide a clear and "realtime" view of the vasculature within the inner part of the person 9.

In some variants of this embodiment, the support information comprises a visual representation of the determined local blood pressure at the tip of the catheter 11 and/or of a difference between the determined local blood pressure at the tip of the catheter 11 and a local blood pressure at the tumor 9. For instance, as can be seen from Fig. 4, which shows schematically and exemplarily support information for supporting the user in performing the embolization procedure, the visual representation 50 of the determined local blood pressure at the tip of the catheter 11 or of the difference between the determined local blood pressure at the tip of the catheter 11 and the local blood pressure at the tumor 9 can be a numerical value that is shown on a suitable area of the display 23, here, at the top right corner of the display 23. In other variants of this embodiment, the support information comprises a visual representation that indicates whether the catheter 11 should be positioned closer to or farther away from the tumor 9 for releasing the embolization agent, wherein the visual representation can be, for instance, plain textual indications, such as "closer" and "farther away" (not shown in the figures).

The support information generating unit 14, here, is adapted to generate the support information further based on the live image data, wherein the support information comprises a visual representation of the tracked position of the catheter 11. For instance, in some variants of this embodiment, the position tracking unit 17 is adapted to track the position of the entire length of the catheter 11, including the elongated body and the tip, within the person 8 and the support information generating unit 14 is adapted to generate, as a part of the support information, overlay image data comprising the live image data with the visual representation of the entire length of the catheter 11 within the person 8 overlaid thereon.

In this embodiment, the support apparatus 2 further comprises a pre- procedural image data providing unit 15 for providing pre-procedural image data showing an inner part of the person 8, which includes the tumor 9. Here, the pre-procedural image data providing unit 15 is a storage medium, such as a hard-disk, an optical disk or another non- volatile computer storage medium, like a flash memory, on which the pre-procedural image data is stored. The stored pre-procedural image data are image data which preferably provide an extensive tumor characterization.

The support information generating unit 14, here, is adapted to fuse the live image data and the pre-procedural image data to generate fused image data 51 and to generate the support information further based on the fused image data 51. For instance, in some variants of this embodiment, the position tracking unit 17 is adapted to track the position of the entire length of the catheter 11, including the elongated body and the tip, within the person 8 and the support information generating unit 14 is adapted to generate, as a part of the support information, overlay image data 52 comprising the fused image data 51 with the visual representation 53 of the entire length of the catheter 11 within the person 8 overlaid thereon. For instance, the visual representation 53 of the entire length of the catheter 11 can be a two-dimensional visual representation that two-dimensionally represents the shape of the catheter 11 at the tracked position, here, the entire length, of the catheter 11 (see Fig. 4).

In this embodiment, the support apparatus 2 further comprises a segmentation providing unit 19 for providing a segmentation of blood vessels downstream of the catheter 11 in image data showing an inner part of the person 8, which includes the tumor 9. Here, the segmentation is obtained from a pre-procedural segmentation process that has been performed, manually or automatically, on the pre-procedural image data. Thus, the segmentation providing unit 19 is a storage medium, such as a hard-disk, an optical disk or another non- volatile computer storage medium, like a flash memory, on which the segmentation obtained by the pre-procedural segmentation process is stored.

The support apparatus 2, here, further comprises a simulation unit 20 for simulating which parts of the tumor 9 will be treated by the released embolization agent based on the determined local blood pressure at the tip of the catheter 11 and on the segmentation.

The support information generating unit 14, here, is adapted to generate the support information such that it comprises a visual representation of the result of the simulation. For instance, in some variants of this embodiment, the visual representation 54 of the result of the simulation is a coloring or shading of the parts of the tumor 9 that will be treated by the released embolization agent, wherein the coloring or shading is, here, overlaid on image data showing an inner part of the person 8, which includes the tumor 9 (herein referred to as "virtual release") (see Fig. 4). The image data, here, is the fused image data 51. Here, the simulation unit 20 is adapted to simulate, in addition to the parts of the tumor 9 that will be treated by the released embolization agent, also the parts of the region surrounding the tumor 9 that will be affected by the released embolization agent. These parts are also shown to the user as part of the visual representation 54.

In this embodiment, the support apparatus 2 further comprises a dose delivery determining unit 21 for determining a radiation dose delivered to the tumor 9 during the embolization procedure based on the simulated parts of the tumor 9 that will be treated by the released embolization agent.

In the following, an embodiment of a support method for supporting a user in performing an embolization procedure during which an insertion element 11 is to be inserted into a living being 8 in order to release an embolization agent for treating a target region 9 within the person 8 will be exemplarily described with reference to a flowchart shown in Fig. 5. The support method can be performed, for instance, with the support apparatus 2 described with reference to Fig. 1.

In step 101, the support apparatus 2 is initialized. In step 102, the position of the insertion element 11 within the living being 8 is tracked, by a position tracking unit 17. In step 103, the local blood pressure at the insertion element 11 within the living being 8 is determined, by a pressure determining unit 18. In step 104, support information is generated based on the tracked position of the insertion element 11 and the determined local blood pressure at the insertion element 11, by a support information generating unit 14. In step 105, the support information is shown to the user, by a display 23. In step 106, it is determined whether an abort criterion is fulfilled, wherein, if the abort criterion is not fulfilled, the support method continues with step 102. Otherwise the support method ends in step 107. The abort criterion may be, for instance, whether the user has input an abort command into the support apparatus 2 by using the input unit 22 or whether the embolization agent has been released for treating the target region 9.

Although in the above described embodiments and/or variants thereof, the position tracking unit is adapted to track the position of the insertion element by using fiber optic shape sensing and the pressure determining unit is adapted to determine the local blood pressure at the insertion element by using fiber optic pressure sensing, in other embodiments, other technologies can be used for performing the tracking and/or sensing. For instance, the position tracking unit can be adapted to track the position of the insertion element by using electromagnetic tracking technology and/or the pressure determining unit can be adapted to determine the local blood pressure at the insertion element by using a conventional arterial line (also known as "a-line"). In this case, pressured saline is used to transmit a pressure waveform to a transducer outside the living being, wherein the transducer transforms the pressure waveform into an electrical pressure signal.

Although in the above described embodiments and/or variants thereof, the live image data providing unit is a C-arm fluoroscopy device comprising an x-ray tube for emitting x-rays that are to traverse the living being and an x-ray detector for detecting the x- rays after they have traversed the living being, in other embodiments, the live image data providing unit can be, for instance, an ultrasound device, a magnetic resonance imaging (MRI) device, or the like.

Although in the above described embodiments and/or variants thereof, the segmentation is obtained from a pre-procedural segmentation process that has been performed, manually or automatically, on the pre-procedural image data, in other

embodiments, the segmentation can be obtained from a segmentation process, in particular, a "real-time" segmentation process, that is automatically performed on the image data, e.g., the live image data or the fused image data.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing 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 unit or device may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Operations like the tracking of the position of the insertion element within the living being, the sensing of the local blood pressure at the insertion element within the living being, the generation of the support information based on the tracked position of the insertion element and the determined local blood pressure at the insertion element, et cetera performed by one or several units or devices can be performed by any other number of units or devices. For instance, the position tracking unit can be integrated with the pressure determining unit into a single unit or device. The operations and/or the control of the support apparatus in accordance with the support method may be implemented as program code of a computer program and/or as dedicated hardware. The 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 part of other 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. The invention relates to a support apparatus for supporting a user in performing an embolization procedure during which an insertion element is to be inserted into a living being in order to release an embolization agent for treating a target region within the living being. A position tracking unit tracks the position of the insertion element within the living being and a pressure determining unit determines the local blood pressure at the insertion element within the living being. Based on the tracked position of the insertion element and the determined local blood pressure at the insertion element, a support information generating unit generates support information which is shown to the user on a display. It is thus possible to provide the user with additional information that may allow him/her to more accurately release the embolization agent.

Claims

CLAIMS:

1. A support apparatus for supporting a user in performing an embolization procedure during which an insertion element (11) is to be inserted into a living being (8) in order to release an embolization agent for treating a target region (9) within the living being (8), wherein the support apparatus (2) comprises:

a position tracking unit (17) for tracking the position of the insertion element (11) within the living being (8),

a pressure determining unit (18) for determining the local blood pressure at the insertion element (11) within the living being (8),

a support information generating unit (14) for generating support information (50, 51, 53, 54) based on the tracked position of the insertion element (11) and the determined local blood pressure at the insertion element (11), and

a display (23) for showing the support information (50, 51, 53, 54) to the user, characterized in that the support apparatus (2) further comprises: a simulation unit (20) for simulating which parts of the target region (9) will be treated by the released embolization agent based on the determined local blood pressure at the insertion element (11),

wherein the support information generating unit (14) is adapted to generate the support information (50, 51, 53, 54) such that it comprises a visual representation (54) of the result of the simulation.

2. The support apparatus as defined in claim 1, wherein the support information (50, 51, 53, 54) comprises a visual representation (50) of the determined local blood pressure at the insertion element (11) and/or of a difference between the determined local blood pressure at the insertion element (11) and a local blood pressure at the target region (9).

3. The support apparatus as defined in claim 1, wherein the support information (50, 51, 53, 54) comprises a visual representation that indicates whether the insertion element (11) should be positioned closer to or farther away from the target region (9) for releasing the embolization agent.

4. The support apparatus as defined in claim 1, wherein the support apparatus (2) further comprises:

a live image data providing unit (3) for providing live image data showing an inner part of the living being (8), which includes the target region (9),

wherein the support information generating unit (14) is adapted to generate the support information (50, 51, 53, 54) further based on the live image data, wherein the support information (50, 51, 53, 54) comprises a visual representation (53) of the tracked position of the insertion element (11).

5. The support apparatus as defined in claim 4, wherein the support apparatus (2) further comprises:

a pre-procedural image data providing unit (15) for providing pre-procedural image data showing an inner part of the living being (8), which includes the target region (9), wherein the support information generating unit (14) is adapted to fuse the live image data and the pre-procedural image data to generate fused image data (51) and to generate the support information (50, 51, 53, 54) further based on the fused image data (51).

6. The support apparatus as defined in claim 1, wherein the support apparatus (2) further comprises:

a segmentation providing unit (19) for providing a segmentation of blood vessels downstream of the insertion element (11) in image data showing an inner part of the living being (8), which includes the target region (9), wherein the simulation unit (20) is adapted to further base the simulation on the segmentation.

7. The support apparatus as defined in claim 6, wherein the segmentation providing unit (19) is adapted to generate the segmentation using an automatic segmentation process that is performed on the image data, wherein the automatic segmentation process is started from the tracked position of the insertion element (11).

8. The support apparatus as defined in claim 1, wherein the simulation unit (20) is adapted to further base the simulation on the local venous pressure and/or on local tissue properties at the insertion element (11).

9. The support apparatus as defined in claim 1, wherein the embolization procedure is a radioembolization procedure and wherein the support apparatus (2) further comprises:

a dose delivery determining unit (21) for determining a radiation dose delivered to the target region (9) during the embolization procedure based on the simulated parts of the target region (9) that will be treated by the released embolization agent.

10. The support apparatus as defined in claim 1, wherein the position tracking unit (17) is adapted to track the position of the insertion element (11) by using electromagnetic tracking technology.

11. The support apparatus as defined in claim 1 , wherein the position tracking unit (17) is adapted to track the position of the insertion element (11) by using fiber optic shape sensing and/or the pressure determining unit (18) is adapted to determine the local blood pressure at the insertion element (11) by using fiber optic pressure sensing.

12. An embolization system for performing an embolization procedure during which an insertion element (11) is to be inserted into a living being (8) in order to release an embolization agent for treating a target region (9) within the living being (8), wherein the embolization system (1) comprises:

the insertion element (11), and

the support apparatus (2) as defined in claim 1.

13. A support method for supporting a user in performing an embolization procedure during which an insertion element (11) is to be inserted into a living being (8) in order to release an embolization agent for treating a target region (9) within the living being

(8), wherein the support method comprises:

tracking the position of the insertion element (11) within the living being (8), by a position tracking unit (17),

- determining the local blood pressure at the insertion element (11) within the living being (8), by a pressure determining unit (18),

generating support information (50, 51, 53, 54) based on the tracked position of the insertion element (11) and the determined local blood pressure at the insertion element

(11), by a support information generating unit (14), and showing the support information (50, 51, 53, 54) to the user, by a display (23), characterized in that the support method further comprises:

simulating which parts of the target region (9) will be treated by the released embolization agent based on the determined local blood pressure at the insertion element (11), by a simulation unit (20),

wherein the support information (50, 51, 53, 54) is generated such that it comprises a visual representation (54) of the result of the simulation.

14. A support computer program for supporting a user in performing an

embolization procedure during which an insertion element (11) is to be inserted into a living being (8) in order to release an embolization agent for treating a target region (9) within the living being (8), wherein the support computer program comprises program code means for causing a support apparatus (2) as defined in claim 1 to carry out the steps of the support method as defined in claim 13, when the support computer program is run on a computer controlling the support apparatus (2).