DE102008005477A1 - Control device operating method for C-arm X-ray device, involves determining two dimensional visualization of modified reconstruction and displaying to operator, where value of operating parameter is varied from another value of parameter - Google Patents

Abstract

A recording arrangement (1) of an X-ray system comprises an X-ray source (2) and an X-ray detector (3). A control device (7) of the X-ray system controls the receiving arrangement (1) in such a way that the X-ray source (2) and the X-ray detector (3) are pivoted first / second times around a pivotal axis (15) around an examination subject (6). The control device (7) controls the receiving arrangement (1) during the first / second pivoting such that the X-ray detector (3) detects a first / second number (n1 / n2) of first / second two-dimensional projection images (P / P ') and the control device (7), the X-ray source (2) for generating each first / second projection image (P / P ') emits a first / second X-ray dose (D1 / D2) and operating parameters of the X-ray source (2) first / second values. The first number (n1) is smaller than the second number (n2). Alternatively or additionally, the first X-ray dose (D1) is smaller than the second X-ray dose (D2) and / or the first values of the operating parameters are different from the second values of the operating parameters. Based on the first / second projection images (P / P '), the control device (7) determines a first / second three-dimensional reconstruction (R / R') of the examination object (6) and registers the reconstructions (R, R ') relative to one another. The control device (7) modifies the second reconstruction (R ') on the basis of the first reconstruction (R). It determines ...

Description

• – wobei die Steuereinrichtung eine Aufnahmeanordnung der Röntgenanlage, die eine Röntgenquelle und einen Röntgendetektor umfasst, derart ansteuert, dass die Röntgenquelle und der Röntgendetektor ein erstes Mal um eine Schwenkachse um ein Untersuchungsobjekt herum verschwenkt werden,
• – wobei die Steuereinrichtung die Aufnahmeanordnung während des erstmaligen Verschwenkens derart ansteuert, dass der Röntgendetektor eine erste Anzahl von ersten zweidimensionalen Projektionsbildern erfasst und der Steuereinrichtung zuführt, die Röntgenquelle zum Erzeugen jedes ersten zweidimensionalen Projektionsbildes eine erste Röntgendosis emittiert und Betriebsparameter der Röntgenquelle erste Werte aufweisen,
• – wobei die Steuereinrichtung die Aufnahmeanordnung der Röntgenanlage sodann derart ansteuert, dass die Röntgenquelle und der Röntgendetektor ein zweites Mal um die Schwenkachse um das Untersuchungsobjekt herum verschwenkt werden,
• – wobei die Steuereinrichtung die Aufnahmeanordnung während des zweitmaligen Verschwenkens derart ansteuert, dass der Röntgendetektor eine zweite Anzahl von zweiten zweidimensionalen Projektionsbildern erfasst und der Steuereinrichtung zuführt, die Röntgenquelle zum Erzeugen jedes zweiten zweidimensionalen Projektionsbildes eine zweite Röntgendosis emittiert und die Betriebsparameter der Röntgenquelle zweite Werte aufweisen,
• – wobei die Steuereinrichtung anhand der ersten zweidimensionalen Projektionsbilder eine erste dreidimensionale Rekonstruktion des Untersuchungsobjekts ermittelt,
• – wobei die Steuereinrichtung anhand der zweiten zweidimensionalen Projektionsbilder eine zweite dreidimensionale Rekonstruktion des Untersuchungsobjekts ermittelt,
• – wobei die Steuereinrichtung die erste dreidimensionale Rekonstruktion und die zweite dreidimensionale Rekonstruktion des Untersuchungsobjekts relativ zueinander registriert,
• – wobei die Steuereinrichtung die zweite dreidimensionale Rekonstruktion des Untersuchungsobjekts anhand der ersten dreidimensionalen Rekonstruktion des Untersuchungsobjekts modifiziert,
• – wobei die Steuereinrichtung mindestens eine zweidimensionale Visualisierung der modifizierten zweiten dreidimensionalen Rekonstruktion des Untersuchungsobjekts ermittelt und über ein Sichtgerät an einen Anwender ausgibt.

The present invention relates to an operating method for a control device of an X-ray machine,

• Wherein the control device controls a receiving arrangement of the X-ray system, which comprises an X-ray source and an X-ray detector, in such a way that the X-ray source and the X-ray detector are pivoted around a subject for a first time around a pivot axis,
• Wherein the control device controls the recording arrangement during the first pivoting in such a way that the x-ray detector acquires and supplies to the control device a first number of first two-dimensional projection images, the x-ray source emits a first x-ray dose to generate each first two-dimensional projection image and operating parameters of the x-ray source have first values,
• - wherein the control device then controls the receiving arrangement of the X-ray system in such a way that the X-ray source and the X-ray detector are pivoted a second time around the pivot axis about the examination subject,
• Wherein the control device activates the recording arrangement during the second pivoting in such a way that the x-ray detector detects a second number of second two-dimensional projection images and feeds them to the control device, the x-ray source emits a second x-ray dose for producing each second two-dimensional projection image and the operating parameters of the x-ray source have second values,
• Wherein the control device determines a first three-dimensional reconstruction of the examination subject based on the first two-dimensional projection images,
• Wherein the control device determines a second three-dimensional reconstruction of the examination subject based on the second two-dimensional projection images,
• Wherein the control device registers the first three-dimensional reconstruction and the second three-dimensional reconstruction of the examination object relative to one another,
• Wherein the control device modifies the second three-dimensional reconstruction of the examination subject on the basis of the first three-dimensional reconstruction of the examination subject,
• - Wherein the control device determines at least a two-dimensional visualization of the modified second three-dimensional reconstruction of the examination object and outputs via a viewing device to a user.

The The present invention further relates to an operating program that Machine code includes its execution by a control device an X-ray system causes the control device performs such an operating method.

Farther The present invention relates to a data carrier which is stored in machine-readable form such an operating method. Also, the present invention relates to a control device for an X-ray machine with such an operating program is programmed.

• – wobei die Röntgenanlage eine Aufnahmeanordnung aufweist, die eine Röntgenquelle und einen Röntgendetektor umfasst,
• – wobei die Röntgenquelle und der Röntgendetektor um eine Schwenkachse um ein Untersuchungsobjekt herum verschwenkbar sind,
• – wobei die Röntgenanlage ein Sichtgerät aufweist,
• – wobei die Röntgenanlage eine Steuereinrichtung aufweist, die wie obenstehend erläutert ausgebildet ist und mit der Aufnahmeanordnung und dem Sichtgerät datentechnisch verbunden ist, so dass sie im Betrieb der Röntgenanlage ein Betriebsverfahren der obenstehend beschriebenen Art ausführt.

Finally, the present invention relates to an X-ray system,

• Wherein the X-ray system has a receiving arrangement which comprises an X-ray source and an X-ray detector,
• Wherein the X-ray source and the X-ray detector are pivotable about a pivot about an object to be examined,
• - wherein the X-ray system has a viewing device,
• - wherein the X-ray system comprises a control device which is formed as explained above and is connected to the recording device and the display device data technically, so that it performs an operating method of the type described above during operation of the X-ray system.

The objects described above are known. Purely by way of example is the technical essay "Partially Rigid Bone Registration in CT Angiography" by Martin Urschler et al., Computer Vision Winter Workshop 2006, Telc, Czech Republic, 6 to 8 February, pages 1 to 6 directed.

• – der Fachaufsatz „Bone-Subtraction CT Angiography for the Evaluation of Intracranial Aneurysms" von B. F. Tomandl et al., American Journal of Neuroradiology, Januar 2006, Seiten 55 bis 59 ;
• – der Fachaufsatz "CT Angiography of the Circle of Willis and Intracranial Internal Carotid Arteries: Maximum Intensity Projection with Matched Mask Bone Elimination – Feasibility Study" von Henk W. Venema et al., Radiology 2001, Heft 218, Seiten 893 bis 898 ; sowie
• – der Fachaufsatz "Circle of Willis at CT Angiography: Dose Reduction and Image Quality – Reducing Tube Voltage and Increasing Tube Current Settings" von Anett Waaijer et al., Radiology, Band 242, Heft 3 (März 2007) .

Other relevant articles are, for example

• - the technical essay "Bone-Subtraction CT Angiography for the Evaluation of Intracranial Aneurysms" by BF Tomandl et al., American Journal of Neuroradiology, January 2006, pp. 55-59 ;
• - the technical essay "CT Angiography of the Circle of Willis and Intracranial Internal Carotid Arteries: Maximum Intensity Projection with Matched Mask Bone Elimination - Feasibility Study" by Henk W. Venema et al., Radiology 2001, No. 218, pp. 893-898 ; such as
• - the technical essay "Circle of Willis at CT Angiography: Dose Reduction and Image Quality - Reducing Tube Voltage and Increasing Tube Current Settings" by Anett Waaijer et al., Radiology, Volume 242, Issue 3 (March 2007) ,

To assess the risk of rupture of an aneurysm and to optimize treatment planning, the simulation of blood flow in patient-specific computer models of the vessels is included new, innovative process. For optimal simulation of the blood flow, however, the creation of the patient-specific computer model is required beforehand. The optimal imaging modality for creating the patient-specific computer model is 3D-DSA rotational angiography with C-arm angiography systems. The reason for this is that with such systems the highest resolution can be achieved. With regard to the cross-modality workflow, however, the use of C-arm angiography systems is not meaningful since in such systems, a catheter is already introduced into the examination subject for admission because a direct arterial injection of a contrast agent is required. Alternative imaging modalities such as, for example, computer tomography or magnetic resonance systems can either manage completely without contrast medium or by means of only venous injected contrast media. However, these non-invasive imaging methods have only a poorer spatial resolution, which has a negative impact on the accuracy of the simulation.

Farther is used for many applications - both in diagnostics, but recently also increasingly for the treatment planning control and during the intervention - one detailed representation of the vessels (arteries and veins) in three-dimensional space. in this connection take the requirements for the representation of smaller and smallest Vessels continuously closed. Of especially big Significance is this requirement, especially in neuroradiological Applications. In principle, however, these requirements apply equally also for other applications, for example in the field of Oncology, for the assessment of angiogenesis or in vascular malformations.

As already mentioned, can for the representation of the Prior art vessels have a plurality of modalities used, however, depending on the application and the requirements resulting from the application exhibit. For example, magnetic resonance techniques are above all else limited in resolution or become too expensive and too expensive. By CT angiography equipment is already a better resolution achieved. Also in CT angiography systems However, a representation of smaller vessels is only limited possible. On the other hand, these two Modalities have the advantage that either no contrast agent must be used (magnetic resonance) or the contrast agent venous can be administered (magnetic resonance, computed tomography).

A improved display of even smaller vessels is already using 3D rotational angiography in C-arm systems today achieved with flat panel detectors. These representations are in subtraction mode (DSA) created. Due to the use of the DSA mode, it is necessary create two three-dimensional records and from each other subtracting one each of the three-dimensional datasets is produced with and without contrast agent. By this procedure Already today, a very accurate representation of small vessels be achieved. The procedure is only achievable by the Contrast resolution limited. Because small vessels contain only small amounts of contrast media and are therefore included only rough contrast resolution insufficient from separating surrounding tissue. In the prior art are for a 3D DSA usually 100 to 200 shots with and without contrast agent made taking the recording parameters for both acquisitions usually identical.

It is of course possible, the number of Increase recordings per acquisition run and so the contrast resolution to improve. However, this procedure means an increase the radiation exposure of the patient. Furthermore, it is in the state The technique required a catheter in the vasculature introduce and at a suitable location the contrast agent to inject arterially. Especially in the field of diagnostics (especially for therapy planning) it would be an advantage if only an intravenous contrast agent injection would be required.

Out Conventional computed tomography is the venous one Injection for Angiographieaufnahme known. The problem of low contrast levels of blood vessels in the area of bony structures is there solved by subtraction angiography.

The Object of the present invention is ways because of which it is possible, even smaller ones and very small vessels in high resolution to represent in three dimensions. Here, however, the burden of the patient with contrast agent and X-ray radiation so be kept as low as possible.

The The object is achieved by an operating method having the features of the claim 1 solved. The task will continue with an operating program the features of claim 10, a disk with the Features of claim 11, a control device with the features of claim 12 and an X-ray system with the features of claim 13 solved. Advantageous embodiments of the Operating method, with which corresponding advantageous embodiments correspond to the other objects mentioned above, are listed in claims 2 to 9, a advantageous embodiment of the X-ray system to complete 14th

According to the invention - in addition on the measures mentioned at the beginning - that the first number is smaller than the second number, the first one X-ray dose smaller than the second X-ray dose is and / or the first values of the operating parameters of the second Values of the operating parameters are different.

For the computer program solves the problem by: it in its execution a corresponding operation of Control device causes.

On the disk is stored such an operating program, the control device with a corresponding operating program programmed. The X-ray system has a corresponding programmed control device.

With the procedure according to the invention is achieved that the contrast agent can be injected intravenously. Introducing a catheter into the vascular system not necessary.

On The reason for the venous injection is a lower one Contrast agent concentration in the blood, so that the vessels - im Comparison to bone - only a relatively low one Experience weakening. Nevertheless, both structures are through the procedure of the invention from each other separable.

A particular strength of the present invention is in the Application in the area of the skull base, in particular in this body region the procedures of the state Often the technology works only insufficiently.

The Object of investigation is usually a human. It is possible, that the control device in the first three-dimensional reconstruction of the human whose bones are segmented and the second three-dimensional Reconstruction of the human using the segmented bones of the human People modified. Alternatively, however, it is possible that the controller the second three-dimensional reconstruction based on the unsegmented first three-dimensional reconstruction of the examination subject modified. This latter approach is hereby independent of whether the object to be examined a human or not.

• – anhand der ersten dreidimensionalen Rekonstruktion des Untersuchungsobjekts Projektionen ermittelt, deren Abbildungsparameter mit denen der zweiten zweidimensionalen Projektionsbilder korrespondieren,
• – anhand der Projektionen die zweiten zweidimensionalen Projektionsbilder modifiziert und
• – anhand der modifizierten zweiten zweidimensionalen Projektionsbilder die modifizierte zweite dreidimensionale Rekonstruktion des Untersuchungsobjekts ermittelt.

It is possible that the control device

• Determined on the basis of the first three-dimensional reconstruction of the examination object projections whose imaging parameters correspond to those of the second two-dimensional projection images,
• - modified on the basis of the projections, the second two-dimensional projection images and
• - Based on the modified second two-dimensional projection images, the modified second three-dimensional reconstruction of the examination object determined.

In a preferred embodiment of the present invention modified the controller the second three-dimensional reconstruction of the examination object, however, without further illustrations and Reconstructions directly from the first three-dimensional reconstruction of the examination subject as such.

It is possible, the first and / or the second three-dimensional Reconstruction of the examination subject to use as they is. However, it is preferred that the control device, the first and / or the second three-dimensional reconstruction of the examination object before modifying the second three-dimensional reconstruction of the examination object filters. The filtering can - especially for the first three-dimensional reconstruction - such be done that the respective filtered reconstruction noise-optimized is.

It It is preferred that the first values of the operating parameters of the X-ray source and the second values of the operating parameters of the X-ray source for the recognition of different substances of the examination object are optimized. In particular, the first values of the Operating parameters of the X-ray source for detection optimized by bone, the second values of the operating parameters the X-ray source for the detection of a contrast agent.

The Operating parameters of the X-ray source can in particular their operating voltage, their operating current and / or their operating time include.

Further Advantages and details will become apparent from the following description of embodiments in conjunction with the drawings. In a schematic representation:

1 schematically an x-ray system and

2 to 6 Flowcharts.

According to 1 an X-ray system has a receiving arrangement 1 on. The recording arrangement 1 in this case comprises an X-ray source 2 and an X-ray detector 3 , According to 1 the X-ray machine has a C-arm 4 on which the X-ray source 2 and the X-ray detector 3 are arranged. The x-ray system of 1 is thus designed as a C-arm X-ray system. However, this embodiment is not mandatory. Alternatively, the X-ray system could, for example, as a CT-An be formed position or have manipulators, by means of which the X-ray source 2 and the X-ray detector 3 independently positionable in five or even six axes.

Regardless of the specific design of the recording arrangement 1 is the x-ray detector 3 however, formed as a two-dimensional X-ray detector. By means of the X-ray detector 3 X-ray images P, P 'acquired are therefore two-dimensional projection images. Furthermore, the X-ray source 2 and the X-ray detector 3 regardless of the specific configuration of the X-ray system about a pivot axis 5 around an examination object 6 swiveling around. The examination object 6 This is usually a human.

The X-ray system has according to 1 furthermore a control device 7 and a viewing device 8th on. The control device 7 is with the recording arrangement 1 and the viewing device 8th connected by data technology.

The control device 7 is with an operating program 9 programmed so that it performs an operating procedure during operation of the X-ray system, which is described below in connection with 2 will be explained in more detail. The operating program 9 has machine code for this purpose 10 on top of the controller 7 is directly workable. The execution of the operating program 9 by the control device 7 causes the control device 7 performs such an operating method.

The control device 7 Already at its manufacture with the operating program 9 have been programmed. Alternatively, it is possible to use the operating program 9 the control device 7 via a computer-computer interface (for example, a connection to a LAN or the Internet) to supply. Again, alternatively, it is possible to run the operating program 9 on a disk 11 in machine-readable (preferably electronic) form and save the operating program 9 the control device 7 over the disk 11 supply. The disk 11 is here in 1 purely as a CD-ROM. However, it could also be designed differently, for example as a USB memory stick or as a memory card.

The operating method according to the invention will now be described in connection with 2 explained in more detail below. Complementary 1 to bring with.

According to 2 represents the controller 7 in a step S1 operating parameters of the X-ray source 2 to first values. The operating parameters of the X-ray source 2 In this case, in particular, their operating voltage U, their operating current I and / or their operating time t may include.

The first values of the operating parameters of the X-ray source are preferably determined in the context of step S1 such that they are used for the recognition of a specific substance of the examination subject 6 are optimized. For example, the operating parameters (in particular the operating voltage U as well as the product of operating current I and operating time t) can be determined such that the detection of bones of the examination subject 6 especially possible. In particular, operating voltages U in the range of approximately 120 kV have proved to be advantageous for this purpose.

In a step S2, the control device controls 7 the recording arrangement 1 such that the x-ray source 2 and the X-ray detector 3 around the pivot axis 5 around the examination object 6 to be pivoted around. During this pivoting operation controls the controller 7 the recording arrangement 1 such that the X-ray detector 3 a first number n1 of first two-dimensional projection images P detected and the control device 7 supplies. The X-ray source 3 is in this case controlled in such a way that it emits a first x-ray dose D1 for generating in each case one of the first two-dimensional projection images P and the operating parameters of the x-ray source 2 have the first values determined in step S1.

The Dose D1 results - in connection with the operating voltage U - from the operating current I and the operating time t per Projection image P. The operating current I, for example, at 20 mA, the operating time t at 10 ms, so that the first dose D1 is relatively low. The first number n1 is preferably also relatively low, for example, it can be between 100 and 150, especially at about 125.

In a step S3, the control device 7 the operating parameters of the x-ray source 2 to second values. In general, the second values are in this case determined in such a way that they are used for the detection of another substance of the examination subject 6 are optimized. For example, the second values may be determined such that they are optimized for the detection of a contrast agent. For example, the operating voltage U may be lower than before, in particular only about 80 kV.

In a step S4, the examination subject 6 fed a contrast agent. Step S4 is in 2 only dashed lines, since he is not necessarily from the control device 7 is performed. The feeding of the contrast agent to the examination object 6 can be arterial. Preferably, however, it is venous.

In a step S5, the control unit controls tung 7 the recording arrangement 1 the X-ray system such that the X-ray source 2 and the X-ray detector 3 again around the pivot axis 5 around the examination object 6 to be pivoted around. The control device 7 controls the recording arrangement 1 during this Verschwenkvorgangs such that the X-ray detector 3 a second number n2 of second two-dimensional projection images P 'and the control device 7 supplies. The second number n2 is usually larger than the first number n1. For example, it can be between 300 and 600, in particular between 400 and 500. The X-ray source 2 is from the controller 7 in this case, in such a way that it emits a second X-ray dose D2 to generate each of the second two-dimensional projection images P '. The operating parameters of the X-ray source 2 here have the second values determined in step S3. The second dose D2 is usually greater than the first dose D1. For this purpose, the operating current I may be, for example, 40 mA, the operating time t (per recording) at 20 ms.

As far as described so far, both the numbers n1, n2 and the doses D1, D2 and the operating parameters U, I, t of the X-ray source differ 2 from each other. However, this is not mandatory. Alternatively, it is possible to limit the variation to only one or only two of said values (numbers n1, n2 - doses D1, D2 - operating parameters U, I, t).

In a step S6, the control device determines 7 based on the two-dimensional projection images P detected in step S2, a first three-dimensional reconstruction R of the examination subject 6 , Furthermore, the control device determines 7 in the context of step S6, based on the two-dimensional projection images P 'detected in step S5, a second three-dimensional reconstruction R' of the examination subject 6 , Finally, the controller registers 7 in step S6, the two three-dimensional reconstructions R, R 'of the examination subject 6 relative to each other.

It is possible, based on the first reconstruction R an interesting area of the examination object 6 and during the second pivoting operation (ie, the pivoting operation of step S5) the X-ray source 2 to operate collimated. In this case, it is necessary to determine the first three-dimensional reconstruction R of the examination subject 6 before step S5 preferable. Alternatively or additionally, in order to determine an optimal acquisition time (ie the time required for the second pivoting process), a test bolus can be previously injected and its transfer time determined.

In a step S7, the control device 7 the first and / or the second three-dimensional reconstruction R, R 'of the examination subject 6 filter. The filtering may be, for example, especially for the first three-dimensional reconstruction R of the examination subject 6 - done so that the respective filtered reconstruction R, R 'is noise optimized. Alternatively, the filtering - in particular the second reconstruction R '- can be application-specific.

In a step S8, the controller modifies 7 the second three-dimensional reconstruction R 'of the examination subject 6 , The modification takes place here on the basis of the first three-dimensional reconstruction R of the examination subject 6 , Possible embodiments of step S8 will be described later in connection with FIGS 3 to 6 be explained in more detail.

In a step S9, the control device determines 7 at least one two-dimensional visualization of the modified second two-dimensional reconstruction R 'of the examination subject 6 and gives this visualization via the viewing device 8th to a user 12 out.

In conjunction with the 3 to 6 Below, various possible embodiments of the step S8 of 2 explained in more detail.

According to 3 Step S8 of FIG 2 be divided into a step S11 and a step S12. In step S11, the controller segments 7 in the first three-dimensional reconstruction R the bones of man 6 , In step S12, the controller modifies 7 the second three-dimensional reconstruction R 'based on the segmented bone in step S11.

Alternatively to the embodiment of 3 it is possible to design step S8 as shown in FIG 4 is shown. According to 4 modifies the controller 7 the second three-dimensional reconstruction R 'of the examination subject without first segmenting the first three-dimensional reconstruction R of the examination subject 6 make. The modification of the second three-dimensional reconstruction R 'thus takes place on the basis of the unsegmented first three-dimensional reconstruction R.

According to 5 it is still possible to step S8 of 2 in steps S21 to S23.

In step S21, the controller determines 7 on the basis of the first three-dimensional reconstruction R of the examination subject 6 for some - preferably for all - second two-dimensional Pro projection images P 'each have a projection P'', the imaging parameters of the respective projection P "corresponding to the imaging parameters of the respective second two-dimensional projection images P'. The projections P '' are in this case analogous to the projection images P, P 'two-dimensional. In contrast to the projection images P, P ', however, the projections P "are not by means of the X-ray detector 3 but has been determined purely mathematically on the basis of the first three-dimensional reconstruction R.

In step S22, the controller modifies 7 the second two-dimensional projection images P 'based on the respective corresponding projection P''.

In step S23, the controller determines 7 on the basis of the modified second two-dimensional projection images P ', the modified second three-dimensional reconstruction R' of the examination subject 6 ,

Again alternatively, it is possible to carry out the step S8 of FIG 2 to shape, as in 6 is shown. According to 6 modifies the controller 7 the second three-dimensional reconstruction R 'of the examination subject 6 directly on the basis of the first three-dimensional reconstruction R of the examination subject 6 as such. Thus, in contrast to the design of 5 - no further illustrations and reconstructions.

The embodiments according to the 3 and 4 exclude each other. So they are only possible alternative, but not combinable. In an analogous manner, the embodiments according to the close 5 and 6 mutually exclusive, so that they can only be realized as an alternative, but can not be combined with each other. However, it is possible the embodiments of 3 and 4 with the embodiments of 5 and 6 to combine.

• – Prä-interventionelle Erstellung einer modifizierten Rekonstruktion R' nach obigem Betriebsverfahren, insbesondere mit venöser Injektion des Kontrastmittels.
• – Segmentierung der Blutgefäße (sei es in der gesamten modifizierten Rekonstruktion R', sei es in einem Teilbereich der modifizierten Rekonstruktion R') und anhand der Gefäße Erstellen eines patientenindividuellen dreidimensionalen Modells.
• – CFD-Simulation des Blutflusses (unter Einbeziehen üblicher Randbedingungen) und Bereitstellen der Ergebnisse.
• – Risikobewertung zur Therapie-Interventionsentscheidung und gegebenenfalls Therapieplanung, Intervention und Interventionskontrolle.

Due to the procedure according to the invention, it is possible, in particular, to realize a modified workflow in the context of CFD simulations. The workflow essentially has the following process steps:

• - Pre-interventional creation of a modified reconstruction R 'according to the above operating method, in particular with venous injection of the contrast agent.
• - Segmentation of the blood vessels (be it in the entire modified reconstruction R ', be it in a portion of the modified reconstruction R') and based on the vessels creating a patient-specific three-dimensional model.
• - CFD simulation of blood flow (incorporating common constraints) and providing results.
• - Risk assessment for therapy intervention decision and if necessary therapy planning, intervention and intervention control.

The Embodiments of the invention have many Advantages. So it is possible in particular, high-resolution Patient-specific three-dimensional geometries of the cerebral Vessels - also at the base of the skull - too create. This is of great importance as an essential Proportion of all aneurysms (about 30%) in this area. in this connection can - especially due to the use of a C-arm X-ray system - the Picture in low contrast mode. Furthermore, it is possible the records already several days before the actual To create intervention. Thus, a time consuming High quality CFD simulation for intervention decision and therapy planning are performed.

The The above description is for explanation only of the present invention. The scope of the present invention On the other hand, it is intended solely by the attached Claims to be determined.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited non-patent literature

• "Partially Rigid Bone Registration in CT Angiography" by Martin Urschler et al., Computer Vision Winter Workshop 2006, Telc, Czech Republic, 6 to 8 February, pages 1 to 6 [0005]
• - "Bone-Subtraction CT Angiography for the Evaluation of Intracranial Aneurysms" by BF Tomandl et al., American Journal of Neuroradiology, January 2006, pp. 55-59 [0006]
• - "CT Angiography of the Circle of Willis and Intracranial Internal Carotid Arteries: Maximum Intensity Projection with Matched Mask Bone Elimination - Feasibility Study" by Henk W. Venema et al., Radiology 2001, No. 218, pp. 893-898 [0006]
• - "Circle of Willis at CT Angiography: Dose Reduction and Image Quality - Reducing Tube Voltage and Increasing Tube Current Settings" by Anett Waaijer et al., Radiology, Vol. 242, Issue 3 (March 2007) [0006]

Claims (14)

Operating procedure for a control device ( 7 ) of an X-ray system, - wherein the control device ( 7 ) an admission order ( 1 ) of the X-ray system, which is an X-ray source ( 2 ) and an x-ray detector ( 3 ) in such a way that the X-ray source ( 2 ) and the X-ray detector ( 3 ) a first time around a pivot axis ( 5 ) around an examination object ( 6 ) are pivoted around, - wherein the control device ( 7 ) the reception order ( 1 ) during the first pivoting in such a way that the X-ray detector ( 3 ) detects a first number (n1) of first two-dimensional projection images (P) and the control device ( 7 ), the X-ray source ( 2 ) for generating each first two-dimensional projection image (P) a first X-ray dose (D1) emitted and operating parameters of the X-ray source ( 2 ) have first values, - wherein the control device ( 7 ) the reception order ( 1 ) the X-ray system then controls such that the X-ray source ( 2 ) and the X-ray detector ( 3 ) a second time around the pivot axis ( 5 ) around the examination object ( 6 ) are pivoted around, - wherein the control device ( 7 ) the reception order ( 1 ) during the second-time pivoting in such a way that the X-ray detector ( 3 ) detects a second number (n2) of second two-dimensional projection images (P ') and the control device ( 7 ), the X-ray source ( 2 ) for generating each second two-dimensional projection image (P ') a second X-ray dose (D2) emitted and the operating parameters of the X-ray source ( 2 ) have second values, - wherein the control device ( 7 ) based on the first two-dimensional projection images (P) a first three-dimensional reconstruction (R) of the examination subject ( 6 ), the control device ( 7 ) based on the second two-dimensional projection images (P ') a second three-dimensional reconstruction (R') of the examination subject ( 6 ), the control device ( 7 ) the first three-dimensional reconstruction (R) and the second three-dimensional reconstruction (R ') of the examination subject ( 6 ) registered relative to each other, - wherein the control device ( 7 ) the second three-dimensional reconstruction (R ') of the examination object ( 6 ) based on the first three-dimensional reconstruction (R) of the examination subject ( 6 ), - wherein the control device ( 7 ) at least one two-dimensional visualization of the modified second three-dimensional reconstruction (R ') of the examination subject ( 6 ) and via a viewing device ( 8th ) to a user ( 12 ), wherein the first number (n1) is less than the second number (n2), the first X-ray dose (D1) is less than the second X-ray dose (D2) and / or the first values of the operating parameters of the second values of the operating parameters are different. Operating method according to claim 1, characterized in that the examination object ( 6 ) a human being is that the control device ( 7 ) in the first three-dimensional reconstruction (R) of man ( 6 ) whose bone segmented and that the control device ( 7 ) the second three-dimensional reconstruction (R ') of man ( 6 ) based on the segmented bones of humans ( 6 ) modified. Operating method according to claim 1, characterized in that the control device ( 7 ) the second three-dimensional reconstruction (R ') of the examination object ( 6 ) based on the unsegmented first three-dimensional reconstruction (R) of the examination subject ( 6 ) modified. Operating method according to claim 1, 2 or 3, characterized in that the control device ( 7 ) - based on the first three-dimensional reconstruction (R) of the examination subject ( 6 ) Determines projections (P '') whose mapping parameters correspond to those of the second two-dimensional projection images (P '), - modifies the second two-dimensional projection images (P') on the basis of the projections (P '') and - based on the modified second two-dimensional projection images (P) P ') the modified second three-dimensional reconstruction (R') of the examination subject ( 6 ). Operating method according to claim 1, 2 or 3, characterized in that the control device ( 7 ) the second three-dimensional reconstruction (R ') of the examination object ( 6 ) without further illustrations and reconstructions directly on the basis of the first three-dimensional reconstruction (R) of the examination subject ( 6 ) modified as such. Operating method according to one of the above claims, characterized in that the control device ( 7 ) the first and / or the second three-dimensional reconstruction (R, R ') of the examination subject ( 6 ) before modifying the second three-dimensional reconstruction (R ') of the examination subject ( 6 ) filters. Operating method according to claim 6, characterized that the filtering takes place such that the respective filtered Reconstruction (R, R ') is noise optimized. Operating method according to one of the above claims, characterized in that the first Values of the operating parameters of the X-ray source ( 2 ) and the second values of the operating parameters of the X-ray source ( 2 ) for the detection of different substances of the examination subject ( 6 ) are optimized. Operating method according to one of the above claims, characterized in that the operating parameters of the X-ray source ( 2 ) whose operating voltage (U), whose operating current (I) and / or their operating time (t) include. Operating program, whereby the operating program machine code ( 10 ), whose execution by a control device ( 7 ) of an X-ray system causes the control device ( 7 ) performs an operating method according to any one of the above claims. Data carrier carrying an operating program in machine-readable form ( 9 ) is stored according to claim 10. Control device for an X-ray system, wherein the control device is provided with an operating program ( 9 ) is programmed according to claim 10. X-ray system, - wherein the X-ray system has a recording arrangement ( 1 ) having an X-ray source ( 2 ) and an x-ray detector ( 3 ), wherein the x-ray source ( 2 ) and the X-ray detector ( 3 ) about a pivot axis ( 5 ) around an examination object ( 6 ) are pivotable around, - wherein the X-ray system is a viewing device ( 8th ), wherein the X-ray system has a control device ( 7 ), which is formed according to claim 12 and with the receiving arrangement ( 1 ) and the viewing device ( 8th ) is technically connected, so that it performs an operating method according to one of claims 1 to 9 during operation of the X-ray system. X-ray system according to claim 13, characterized in that the X-ray system is a C-arm ( 4 ) and that the X-ray source ( 2 ) and the X-ray detector ( 3 ) on the C-arm ( 4 ) are arranged.