Patent Description:
<CIT> discloses vessel roadmapping, which includes a vessel display, i.e. the vessel roadmap, computed from vessel phase or pre-navigation imaging, and an intravascular device display computed from device phase, real-time, or live fluoroscopy imaging of an intravascular device in a vessels of a patient. The vessel roadmap is built from contrast enhanced angiographic imaging. With the roadmapping technique, the contrast enhanced vessels are displayed with an overlay of the live imaging of the intravascular device for aiding location of, and navigation of, the intravascular device. This document discloses pruning of the vessel roadmap based on detected device position to display a more focused, more relevant vessel roadmap.

In known roadmapping systems, e. g known from <CIT>, if a clinician changes the geometry of an image acquisition machine during the device phase (e.g. a position of the source/detector of the image acquisition machine and/or a patient table), then a mismatch between the vessel roadmap and the intravascular device occurs. In such situations, a vessel roadmap function may be switched off. Thereafter, a clinician either needs to restore the vessel roadmap position through re-position of the position of the image acquisition machine or the clinician has to recreate the vessel roadmap through a new vessel phase image acquisition process involving subjecting the patient to toxic contrast agent injection and a further round of detailed angiographic (e.g. X-ray) imaging. Angiographic X-ray imaging is a high dose, high detail X-ray imaging technique.

Thus, it is desired to provide vessel roadmapping systems and methods that reduce the number of vessel phase imaging operations. It is further desirable to avoid vessel roadmap mismatches in so far as possible to increase procedure efficiency.

Hence, there may be a need to provide an improved and facilitated way of vessel roadmapping.

Generally, the present invention proposes to provide vessel roadmapping systems and methods that generate a display of live fluoroscopic imaging of an intravascular device within vessels of a patient and a pre-generated vessel roadmap. The systems and methods pan the vessel roadmap in coordination with movement of a field of view of an image acquisition machine obtaining the live fluoroscopic imaging so that registration of the live fluoroscopic imaging and the vessel roadmap is preserved in the displayed overlay. That is, the vessel roadmap is repositioned according to changes of a region of interest (i.e. according to changes in position of the fluoroscopic imaging machine) during the vessel phase, so that the vessel roadmap is re-used and is registered with the fluoroscopic imaging even after changing the region of interest. In this way, live imaging and vessel roadmap mismatches as a result of change in position of the image acquisition machine should seldom occur, if at all, thereby minimizing repeat vessel phase imaging operations.

The object of the present invention is solved by the subject-matter of the independent claims; wherein further embodiments are incorporated in the dependent claims. It should be noted that the following described aspects of the invention apply also for the imaging system, for the computer implemented method as well as for the computer program element and the computer readable medium.

In one embodiment, an imaging system is provided for generating a display including an intravascular device overlayed with a vessel roadmap. The imaging system includes a data receiver configured to receive live fluoroscopic imaging including an intravascular device. An image processing system is configured to receive a vessel roadmap. The image processing system is configured to generate a display including the vessel roadmap and the intravascular device overlayed with the vessel roadmap based on the live fluoroscopic imaging. The image processing system is configured to pan the display of the vessel roadmap corresponding to panning of a field of view of the live fluoroscopic imaging so that the intravascular device is overlayed at a correct location on the vessel roadmap. In this way, as a region of interest (corresponding to a field of view) of the live fluoroscopic imaging is shifted, the vessel roadmap display is corresponding shifted to maintain positional alignment between the live fluoroscopic imaging and the vessel roadmap.

In embodiments, the data receiver is configured to receive device phase field of view data. The image processing system is configured to receive vessel phase field of view of data. The image processing system is configured to determine panning data based on the device phase field of view data and the vessel phase field of view data. The image processing system is configured to pan the display of the vessel roadmap based on the panning data. By assessing the device and vessel phase field of view data, the requisite image space panning for the vessel roadmap is able to be determined. In embodiments, the image processing system is configured to determine a spatial difference between the device phase field of view data and the vessel phase field of view data and to determine the panning data based on the spatial difference. In embodiments, the image processing system is configured to transform the spatial difference into the imaging space as part of determining the panning data. In embodiments, the image processing system is configured to compare biological reference markers in vessel roadmap imaging, from which the vessel roadmap is derived, and the live fluoroscopic imaging to determine panning data and to pan the display of the vessel roadmap based on the panning data.

In embodiments, the image processing system is configured to determine a spatial difference between the device phase field of view data and the vessel phase field of view data, to use the spatial difference in determining the panning data based on a comparison between biological reference markers in vessel roadmap imaging, from which the vessel roadmap is derived, and the live fluoroscopic imaging. A combination of determining a spatial difference in the device and vessel phases and biological reference marker matching allows for sequential coarse and fine vessel roadmap alignment processes, thereby ensuring processing efficiency and accurate overlay registration. In embodiments, the image processing system is configured to obtain mask images from the live fluoroscopic imaging and from the vessel roadmap imaging based on the spatial difference and to compare the mask images to determine the panning data.

In embodiments, the image processing system is configured to receive field of view data associated with a relative position of an image acquisition machine (e.g. detector and/or source thereof) and/or a patient table or other patient support structure from a controller of the image acquisition machine/patient support structure.

In embodiments, the image processing system is configured to pan the display of the vessel roadmap corresponding to panning of a field of view of the live fluoroscopic imaging when (e.g. whenever) a signal indicating a change of field of view of an image acquisition machine for obtaining the live fluoroscopic imaging is received.

In embodiments, the imaging system includes a fluoroscopic image acquisition machine for obtaining the live fluoroscopic imaging and a patient table or other patient support structure. The image processing system is configured to pan the display of the vessel roadmap when the fluoroscopic image acquisition machine and the patient table or other patient support structure move relative to one another, thereby panning the field of view of the live fluoroscopic imaging.

In embodiments, the data receiver is configured to receive angiographic imaging and the image processing system is configured to determine the vessel roadmap based on the angiographic imaging.

In embodiments, the vessel roadmap based on the angiographic imaging received during a vessel phase is generally larger than the received live fluoroscopic imaging. The vessel roadmap thus covers a greater area or larger region of interest. During the vessel phase the detector is set to a relatively large detector size and to a relatively small detector size during the device phase. The angiographic imaging is at a higher level of detail (e.g. higher spatial resolution) than the live fluoroscopic imaging in various embodiments.

In embodiments, panning data represents a selected region of the vessel roadmap that is optionally sized to match the field of view of the fluoroscopic imaging and that is panned to match panning of the field of view of the live fluoroscopic imaging. The overlay of the live fluoroscopic imaging and a selected region of the vessel roadmap corresponding to the panned region of interest produces an overlay for display on the display device. A part of the vessel roadmap and the live intravascular device images are overlayed. The overlay of live fluoroscopic imaging and vessel roadmap shows the intravascular device spatially registered to the part of the vessel roadmap. Steering and locating the intravascular device can thus be assisted, as no mismatch is caused as would result in a panned view of the intravascular device against a static vessel roadmap as in the background art. Panning of the display of the vessel roadmap corresponds to panning of a field of view of the live fluoroscopic imaging so that the intravascular device is overlayed at a correct location on the vessel roadmap. In this way, as a region of interest (corresponding to a field of view) of the live fluoroscopic imaging is shifted, the vessel roadmap display is corresponding shifted to maintain positional alignment between the live fluoroscopic imaging and the vessel roadmap.

In embodiments, during the device phase the detector size is increased or decreased as desired, thus providing a zooming option for the region of interest. The detector position may remain unchanged, while the field of view of the fluoroscopic imaging changes. The detector might change in a direction substantially perpendicular to the detection plane, so that the detector is set to a small detector size during the device phase changing the field of view of the fluoroscopic imaging and providing a zoom-in option, whereas the vessel roadmap received during the vessel phase is optionally sized to match the field of view of the fluoroscopic imaging and that is panned to match panning of the field of view of the live fluoroscopic imaging.

In another embodiment, a computer implemented method for generating a display including an intravascular device overlayed with a vessel roadmap. The computer implemented method includes receiving live fluoroscopic imaging including an intravascular device, receiving a vessel roadmap, generating a display including the vessel roadmap and the intravascular device overlayed on the vessel roadmap based on the live fluoroscopic imaging, and panning the display of the vessel roadmap corresponding to panning of a field of view of the live fluoroscopic imaging so that the intravascular device is overlayed at a correct location on the vessel roadmap.

In embodiments, the method includes receiving vessel imaging and deriving the vessel roadmap from the vessel imaging.

In embodiments, the method includes receiving vessel phase field of view data and device phase field of view data and panning the display of the vessel roadmap based on a spatial difference between the vessel phase field of view data and device phase field of view data.

In embodiments, the method includes comparing biological reference markers in the vessel imaging and the live fluoroscopic imaging based on the spatial difference to determine panning data, wherein panning the display of the vessel roadmap is based on the panning data. In embodiments, the method includes selecting a part of an angiographic mask image, from the vessel imaging, based on the spatial difference and comparing biologic reference markers in the part of the angiographic mask image with a live fluoroscopic mask image, from the live fluoroscopic imaging, to determine the panning data.

The features describe above with respect to the imaging system are applicable to the computer implemented method.

In yet another embodiment, a computer program element is provided that is adapted to implement an imaging system as described herein or adapted to perform the computer implemented method steps described herein when executed by at least one processor.

A computer readable medium is also provided having stored thereon, the computer program element.

As used herein, the term module refers to any hardware, software, firmware, electronic control component, processing logic, and/or processor device, individually or in any combination, including without limitation: application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that executes one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.

<FIG> is a schematic view of an imaging system <NUM> for panning a display of a vessel map in coordination with changes in field of view of live imaging. The following description of the elements of <FIG> makes subsidiary reference to elements in <FIG>, which should be accordingly referenced. The imaging system <NUM> includes an image processing system <NUM>, an image acquisition machine <NUM>, a patient support structure <NUM>, a display device <NUM>, a controller <NUM>, an intravascular device <NUM> and a user interface <NUM>, in accordance with various embodiments. The imaging system <NUM> is configured to generate a display of a vessel roadmap <NUM> from vessel phase, angiographic imaging and to overlay imaging of the intravascular device <NUM> in situ from device phase, live fluoroscopic imaging. When the field of view of the image acquisition machine <NUM> is panned during live fluoroscopic imaging, the vessel roadmap <NUM> is correspondingly panned in image space to maintain registration of the live fluoroscopic imaging <NUM> and the vessel roadmap <NUM>.

The image acquisition machine <NUM> is configured for obtaining intrabody angiographic imaging data <NUM> during a vessel phase and for obtaining live fluoroscopic imaging data <NUM> during a device phase. Although just one image acquisition machine <NUM> is described in the present embodiment, embodiments are possible having respective image acquisition machines for the vessel phase and for the device phase. Generally, the image acquisition machine <NUM> is a 2D X-ray imaging machine. The image acquisition machine <NUM> includes a detector <NUM> and a source <NUM>, which generally is an X-ray radiation source. The image acquisition machine <NUM> includes a controller <NUM> configured to control positioning (e.g. panning position) and other field of view aspects (e.g. beam cross-sectional size), in addition to controlling detection and emission of imaging waves. A patient is, generally, located on patient support structure <NUM>, which is a patient table <NUM> in the illustrated embodiment. The controller <NUM> is configured to control relative positioning of patient support structure <NUM> and iso-center <NUM> of radiation emitted by the source <NUM>. The relative positioning of the patient support structure <NUM> and the iso-center <NUM> is adjustable according to panning directions. The controller <NUM> is configured to output a signal <NUM>, <NUM> indicative of field of view of the image acquisition machine <NUM>, which includes at least position of patient support table <NUM> relative to the iso-center <NUM> in a reference coordinate frame such as x, y and optionally z and rotational directions. The signal <NUM>, <NUM> includes field of view size (e.g. cross-sectional size, which corresponds to active detector size and/or beam size) as well as field of view position data in accordance with some embodiments.

The controller <NUM> is configured to operate a roadmap function that is described herein in terms of two phases. A vessel phase includes acquiring an x-ray series, which contains angiography (vessel imaging with contrast agent) for creating a vessel road map <NUM>. A device phase includes imaging the intravascular device <NUM> for creating live fluoroscopic imaging <NUM>. The image processing system <NUM> is configured to superimpose the vessel roadmap <NUM> and the live fluoroscopic imaging <NUM> including the intravascular device <NUM>. The device phase is repeated in that a stream or video of fluoroscopic images <NUM> are superimposed on the same vessel roadmap <NUM>. The systems and methods described herein allow the image acquisition machine <NUM> to pan its field of view relative to the patient support structure without requiring a repeated vessel phase as the image processing system <NUM> correspondingly pans the vessel map <NUM> and overlays the live fluoroscopic imaging <NUM>.

The display device <NUM> is any monitor, screen, or the like suitable for presenting a graphical user interface (GUI) capable of presenting a combination of live fluoroscopic image <NUM> and vessel map <NUM> in a spatially registered way.

The imaging system <NUM> includes a user interface <NUM>, in embodiments, to allow a clinician to control a field of view of the image acquisition machine <NUM>. In particular, a field of view size and iso-center position is able to be changed through the user interface <NUM>. The user interface <NUM> is a touchscreen, a keyboard, a joy stick, a mouse, a touchpad, a mechanical control, or other user interface or a combination thereof, in various embodiments.

In embodiments, the obtained vessel phase, angiographic imaging data <NUM> and the device phase, live fluoroscopic imaging data <NUM> are provided to the image processing system <NUM> where various image processing operations are performed as will be described further herein, particularly with respect to <FIG> and <NUM>. Generally, the image processing system <NUM> is configured to build a vessel map <NUM> from the angiographic imaging data <NUM> and build a device video <NUM> from the live device imaging <NUM>. The image processing system <NUM> is configured to generate an overlay display of the vessel roadmap <NUM> and the live device imaging <NUM> for display through the display device <NUM>. The image processing system <NUM> is configured to receive a signal <NUM> representing spatial panning of a field of view of the image acquisition machine <NUM>, to transform the spatial panning of the image acquisition machine <NUM> to image space and to correspondingly pan the vessel roadmap <NUM> so that the live device imaging <NUM> is displayed in an accurately registered way on the vessel roadmap <NUM>. The image processing system <NUM> is configured, in some embodiments, to use a spatial difference <NUM> in an iso-center <NUM> of the image acquisition machine between the vessel phase and the device phase and to determine panning data for controlling image space panning of the road vessel map <NUM>. Biological reference marker are additionally or alternatively used for determining panning of the road vessel map <NUM> to match panning of the field of view of the image acquisition machine <NUM>.

The image processing system <NUM> includes at least one processor <NUM> and a computer readable storage device, memory or media <NUM>. The processor <NUM> can be any custom made or commercially available processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among several processors associated with the image processing system <NUM>, a semiconductor based microprocessor (in the form of a microchip or chip set), a macroprocessor, any combination thereof, or generally any device for executing instructions. The computer readable storage device, memory or media <NUM> may include volatile and nonvolatile storage in read-only memory (ROM), random-access memory (RAM), and keep-alive memory (KAM), for example. KAM is a persistent or nonvolatile memory that may be used to store various operating variables while the processor <NUM> is powered down. The computer-readable storage device, memory or media <NUM> may be implemented using any of a number of known memory devices such as PROMs (programmable read-only memory), EPROMs (electrically PROM), EEPROMs (electrically erasable PROM), flash memory, or any other electric, magnetic, optical, or combination memory devices capable of storing data, some of which represent executable instructions, used by the image processing system <NUM> in controlling the imaging system <NUM>. The instructions are configured for executing the modules <NUM> of the image processing system <NUM> of <FIG>, the data flow processes of <FIG> and the methods <NUM> of <FIG> as described further herein.

The instructions may include one or more separate programs, each of which comprises an ordered listing of executable instructions for implementing logical functions. The instructions, when executed by the processor <NUM>, receive and process images from the image acquisition machine <NUM>, perform logic, calculations, methods and/or algorithms for automatically controlling modules <NUM> of the image processing system <NUM>, and generate control signals to a display device <NUM>. In particular, the instructions are operable to generate a spatially registered overlay of a video of device imaging <NUM> and a vessel roadmap <NUM> for display on display device <NUM>, wherein panning of field of view of the image acquisition machine results in a spatially corresponding panning of the displayed part of the vessel roadmap <NUM> to maintain spatial registration with the live device imaging <NUM>. Although only one image processing system <NUM> is shown in <FIG>, embodiments of the imaging system <NUM> can include any number of image processing systems <NUM> that communicate over any suitable communication medium or a combination of communication mediums and that cooperate to process images, perform logic, calculations, methods, and/or algorithms, and generate control signals to automatically control features of the imaging system <NUM>.

In various embodiments, the image processing system <NUM>, such as a general-purpose computer, is operably connected to the image acquisition machine <NUM> and the controller <NUM> to cooperatively control operation of the image acquisition machine <NUM> for performing scans to obtain angiographic imaging data <NUM> during a vessel phase and fluoroscopic imaging data <NUM> during a device phase and to processes the imaging data <NUM>, <NUM> from the image acquisition machine <NUM>. The processed images are presented on the display device <NUM> of the imaging system <NUM> in the form of an overlay.

The image processing system <NUM> includes a number of modules <NUM> for executing the imaging system <NUM>, data flows and methods <NUM> described herein for executing superimposed live fluoroscopy and vessel roadmap <NUM> wherein the vessel roadmap <NUM> pans automatically. The modules <NUM> described herein include at least one processor <NUM>, a memory <NUM> and computer program instructions stored on the memory <NUM> for implementing the various functions and processes described with respect to the modules <NUM>. Although separate modules <NUM> are described herein for particular functions, this does not exclude an integrated topology. Further, the shown modules <NUM> may be divided into further sub-modules. The modules <NUM> are in communication with one another as necessary to implement the features, processes and systems described herein.

The modules <NUM> will be described with reference to the data flow diagram of <FIG> to allow the functions of each module and the data transformations to be readily appreciated.

Data receiver <NUM> is configured to receive an angiographic vessel mask image <NUM>, angiographic vessel imaging <NUM> and vessel phase field of view data <NUM> during a vessel phase from image acquisition machine <NUM> or controller <NUM> thereof. Data receiver <NUM> is configured to receive a live stream of fluoroscopic imaging <NUM>, a fluoroscopic mask image <NUM> and device phase field of view data <NUM> during a device phase from image acquisition machine <NUM> or controller <NUM> thereof. The angiographic vessel imaging <NUM> during the vessel phase and the live fluoroscopic imaging <NUM> during the device phase generally share an iso-center so that the live fluoroscopic imaging is able to be positioned on the vessel roadmap <NUM> without panning of the vessel roadmap <NUM> at initiation of the device phase. The angiographic vessel imaging <NUM> is generally larger, i.e. covers a greater area or larger region of interest, of the patient than the live fluoroscopic imaging <NUM>. That is, the detector <NUM> is set to a relatively large detector size during the vessel phase and to a relatively small detector size during the device phase. The angiographic imaging <NUM> is at a higher level of detail (e.g. higher spatial resolution) than the live fluoroscopic imaging <NUM> in various embodiments. The angiographic vessel mask image <NUM> is obtained in the vessel phase prior to contrast injection, whilst the fluoroscopic mask image <NUM> is obtained in the device phase without the intravascular device <NUM> being imaged.

The modules <NUM> include an angiographic vessel mapper <NUM> configured to construct a vessel road map <NUM>. The vessel road map <NUM> is constructed, in embodiments, by subtracting the angiographic vessel mask image <NUM> from the angiographic vessel imaging <NUM> to substantially isolate vessels from other tissue including bones in the vessel road map <NUM>. Various other processing techniques can be utilized to achieve a clear vessel roadmap <NUM> that substantially shows only blood vessels.

The modules <NUM> include a fluoroscopic vessel imager <NUM> configured to construct live device imaging <NUM> showing substantially only the intravascular device <NUM>. The fluoroscopic vessel imager <NUM> is configured to subtract the fluoroscopic mask image <NUM> from the live fluoroscopic imaging <NUM> so as to remove bones and other tissue from the live device imaging <NUM>. The live device imaging <NUM> generally covers a smaller region of interest than the vessel road map <NUM>.

The modules <NUM> include an overlay module <NUM> configured to combine a part of the vessel roadmap <NUM> and the live device imaging <NUM> (which includes a stream of live images essentially forming a video) as an overlay <NUM>. The overlay <NUM> of live device imaging <NUM> and vessel roadmap <NUM> shows the intravascular device <NUM> spatially registered to the part of the vessel roadmap <NUM> to assist a clinician in steering and locating the intravascular device <NUM>.

Without vessel roadmap panning as described herein, any panning of the field of view of the image acquisition machine <NUM> relative to the patient on the patient support structure <NUM> would result in a panned view of the intravascular device against a static vessel roadmap, thereby causing a mismatch. Modules of the image processing system <NUM>, as described further herein, are able to receive the field of view data <NUM> during the vessel phase from which panning of the image acquisition machine <NUM> is derivable. The image processing system <NUM> determines an amount of panning of the vessel roadmap required to match the panning of the live fluoroscopic imaging <NUM> and adapts the overlay <NUM> accordingly to preserve registration. Determining distance of panning of the vessel roadmap <NUM> as described further below may be performed periodically or it may be triggered by signals from the controller <NUM> indicating movement of the image acquisition machine <NUM> as a result of a clinicians movement command through the user interface <NUM>.

In one embodiment for performing such panning, the image processing system <NUM> includes a field of view delta module <NUM> configured to determine a spatial difference <NUM> between device phase field of view data <NUM> and vessel phase field of view data <NUM>. That is, spatial difference <NUM> is determined in geometric positions of image acquisition machine <NUM> (specifically the iso-center <NUM> thereof) and the patient table <NUM> during the vessel phase as compared to during the device phase, which is representative of any panning of the field of view (movement of the beam iso-center <NUM>) during the device phase. The spatial difference <NUM> is in the frame of reference of the image acquisition machine <NUM>. A transformation module <NUM> is configured to transform the spatial difference to image space using calibration data <NUM> taken from memory <NUM>. In this way, movement of the field of view of the live fluoroscopic imaging <NUM> in image space of the vessel road map <NUM>, e.g. in pixels, is determined. That is, spatial difference in image space <NUM> is obtained through the transformation module <NUM>.

In some embodiments, the spatial difference in image space <NUM> is sufficient to determine amount of panning of the vessel roadmap <NUM> to use in constructing the overlay <NUM>. In the shown embodiment, a further refinement is added in the form a biomarker comparison module <NUM>. The biomarker comparison module <NUM> receives the spatial difference <NUM> and uses it to select a relevant region <NUM> of the angiographic vessel mask image <NUM>. The selected region <NUM> of the angiographic mask image <NUM> is sized to match the size of the live fluoroscopic imaging <NUM> according to the device phase field of view data <NUM> and is positioned away from the iso-center <NUM> (in image space) by an amount according to the spatial difference in image space <NUM>. As such, the angiographic mask image <NUM> is panned based on the spatial difference in image space <NUM> to match panning of the field of view of the live fluoroscopic imaging <NUM>. The biomarker comparison module <NUM> is configured to compare biomarkers (e.g. bones/bone parts) in the selected region <NUM> of the angiographic mask image <NUM> and the fluoroscopy mask image <NUM> to determine any misalignment. Any misalignment can be added to the spatial difference in pixels <NUM> to determine refined panning data <NUM> representative of an amount of panning of the image acquisition machine based on both movement of a field of view of the image acquisition machine during the vessel phase as derived from the field of view data <NUM> and fine control based on biomarker alignment. The biomarker comparison module is configured to compensate small deviations in positioning of the vessel roadmap <NUM> by including such deviations in panning data <NUM>. In one embodiment, the biomarker comparison module <NUM> uses automatic pixel shift, APS, in determining panning data <NUM>, which is a known technology for registering biomarkers. The APS algorithm operates on a panned mask image <NUM> from the vessel phase, where the panning is according to the spatial difference <NUM>, and the mask image <NUM> from the device phase. The mask images <NUM>, <NUM> contain a patient's bone structure which is used by the APS algorithm to calculate a deviation shift to be applied to the vessel roadmap <NUM>.

The panning data <NUM> represents a selected region of the vessel roadmap <NUM> that is optionally sized to match the field of view of the fluoroscopic imaging <NUM> and that is panned to match panning of the field of view of the live fluoroscopic imaging <NUM>. That is, assuming a panning shift in x, y dimensions of the live fluoroscopic imaging <NUM> in imaging space, a corresponding panning shift in image space is computed for the vessel roadmap <NUM>. The panning module <NUM> receives the panning data <NUM> from the biomarker comparison module <NUM> and the vessel roadmap <NUM> from the angiographic vessel mapper <NUM>. The panning module <NUM> is configured to select a panned region of interest <NUM> from the vessel roadmap <NUM> based on the panning data <NUM>. In the illustration of the panning module <NUM>, there is shown the vessel roadmap <NUM> and an initial region of interest <NUM> thereof and a panned region of interest <NUM> thereof that is panned diagonally (in x and y directions) relative to the initial region of interest <NUM>. The initial region of interest <NUM> is set by a clinician through the user interface <NUM> by navigating the field of view of the image acquisition machine <NUM> until the intravascular device <NUM>, such as a catheter and optionally a distal end thereof, comes into view. The panned region of interest can occur when the intravascular device <NUM> (or the distal end thereof) exits the field of view of the live imaging <NUM>, causing the user to change the field of view through the user interface <NUM>. The panning module <NUM> is configured to select the panned region of interest <NUM> as a spatial change from the initial region of interest as defined by the panning data <NUM>. The panning data <NUM> is determined in various embodiments based on a change in field of view data <NUM> for the live imaging <NUM> during the device phase and optionally also based on biomarker registration as has been described above. The panned region of interest <NUM> of the vessel map <NUM>, or data representing such, is provided to the overlay module <NUM>.

The overlay module <NUM> is configured to overlay the live video device imaging <NUM> and a selected region of the vessel map <NUM> corresponding to the panned region of interest <NUM> to produce the overlay <NUM> for display on the display device.

Referring now to <FIG>, and with continued reference to <FIG> and <FIG>, a flowchart illustrates a computer implemented method <NUM> for generating an overlay that pans the vessel roadmap <NUM> to match panning of the live fluoroscopic device imaging <NUM>. The computer implemented method <NUM> can be performed by the imaging system <NUM> of <FIG> in accordance with the present disclosure. As can be appreciated in light of the disclosure, the order of operation within the method is not limited to the sequential execution as illustrated in <FIG>, but may be performed in one or more varying orders as applicable and in accordance with the present disclosure. In various embodiments, the method <NUM> can be scheduled to run based on one or more predetermined events (e.g. panning of field of view of live fluoroscopic imaging <NUM>), and/or can run continuously during operation of the imaging system <NUM>.

During the course of the device phase, the clinician may pan a region of interest by changing a field of view of the image acquisition machine through the user interface (which operates on the position of the detector <NUM>, the source <NUM> and/or the patient support structure <NUM>). The computer implement method repositions the vessel roadmap <NUM> during the device phase so that the vessel roadmap <NUM> remains useful, and accurately registered with the live device imaging <NUM>, after changing the region of interest. There are a number of instances whereby it is desirable for the clinician to change the region of interest. For example, the clinician may decrease the size of the field of view of the live imaging <NUM> through the user interface <NUM> and navigate by panning the field of view of the image acquisition machine <NUM> to a point where the intravascular device <NUM> is viewed, e.g. navigates from a central region to the initial region of interest <NUM> in <FIG>. The computer implemented methods <NUM> and imaging systems <NUM> described herein pan the vessel roadmap <NUM> to the correct location. In another example, the field of view of the image acquisition machine is panned because a distal end of the intravascular device <NUM> goes outside of the field of view. The computer implemented methods <NUM> and imaging systems <NUM> described herein pan the vessel roadmap <NUM> to the correct location. As a specific, non-limiting example, a clinician may change the field of view from the initial region of interest <NUM> as the intravascular device <NUM> has exited the field of view of the live imaging <NUM> as shown by the arrow in the overlay <NUM> of <FIG>. Without corresponding panning of the vessel roadmap <NUM>, the initial regional interest <NUM> of the vessel roadmap <NUM> would be overlayed with the panned device image shown in the solid box <NUM>, which would result in a mismatch. The methods <NUM> and systems <NUM> described herein prevent such mismatches.

The computer implemented method <NUM> includes a step <NUM> of receiving angiographic imaging data <NUM>, <NUM> and vessel phase field of view data <NUM>. In step <NUM>, a vessel roadmap <NUM> is formed from the angiographic imaging data <NUM>, <NUM> through angiographic vessel mapper <NUM> during a vessel phase.

The computer implemented method <NUM> includes a step <NUM> of receiving live fluoroscopic imaging data <NUM>, <NUM> and device phase field of view data <NUM>. In step <NUM>, a live device image <NUM> is formed from the live fluoroscopic imaging data <NUM>, <NUM> through the fluoroscopic vessel imager <NUM>. The receiving steps <NUM>, <NUM> are carried out through the data receiver <NUM>. In embodiments, a clinician selects to reduce a field of view of the live device imaging <NUM> through the user interface <NUM>. The clinician may also pan the field of view of the live device imaging <NUM> through the user interface during the device phase. The user's entries through the user interface cause field of view changes to be carried out by the image acquisition machine <NUM>.

The computer implemented method <NUM> includes steps <NUM> to <NUM> for determining panning data <NUM> that represents an amount and direction by which the vessel roadmap <NUM> is to be panned to match panning of the field of view of the live fluoroscopic imaging <NUM>. The vessel roadmap <NUM> panning distance and direction, as embodied in the panning data <NUM>, are determined based on spatial difference <NUM> between relative position of table <NUM> and the iso-center <NUM> during the vessel phase and the corresponding relative position during the device phase and optionally also on automatic pixel shift operation on a panned mask image <NUM> (panned based on the spatial difference) from the vessel phase and the mask image <NUM> from the device phase.

More specifically, the computer implemented method <NUM> includes a step <NUM> of determining the geometric difference between the device phase and the vessel phase field of view data <NUM>, <NUM> to determine spatial difference data <NUM>. Step <NUM> is performed through the field of view delta module <NUM>. The spatial difference data <NUM> is transformed from real space in a coordinate frame of the image acquisition machine <NUM> to image space of the vessel roadmap <NUM>. Such transformation is performed through the transformation module <NUM> by calculation using calibration data <NUM> from memory <NUM>.

The computer implemented method <NUM> includes a step <NUM> of selecting a region <NUM> of the angiographic mask image <NUM> by moving an initial region at the start of the vessel phase according to the spatial difference <NUM> to obtain the selected region <NUM> of the angiographic mask image <NUM>. The selected region <NUM> essentially maps panning of the field of view of the image acquisition machine <NUM> to panning in image space so that spatially corresponding imaging from the device and vessel phases are compared in step <NUM>.

The computer implemented method <NUM> includes a step <NUM> of performing biomarker comparison between the selected region <NUM> of the vessel mask image <NUM> and the fluoroscopic mask image <NUM> to obtain panning data. In particular step <NUM> determines an amount and direction of shift, in image space of the vessel roadmap <NUM>, to align biomarkers of the selected region <NUM> of the angiographic mask image <NUM> with the corresponding biomarkers of the fluoroscopy mask image <NUM>. The fine pixel shift from step <NUM> and the spatial difference <NUM> from step <NUM> are incorporated in the panning data <NUM>. Steps <NUM> and <NUM> are performed through the biomarker comparison module <NUM>.

The computer implemented method <NUM> includes a step <NUM> of displaying an overlay <NUM> of a panned region of interest <NUM> of the vessel map and the live device imaging <NUM>. The panned region of interest <NUM> is determined according to the panning data <NUM>. The panning data <NUM> essentially maps panning movement of the field of view of the image acquisition machine <NUM> to matching panning movement of the region of interest in image space of the vessel roadmap <NUM> as shown by the panning movement between the initial region of interest <NUM> and the panned region of interest <NUM> shown in <FIG>. The panning of the vessel map <NUM> occurs through the panning module <NUM>. The combination of live device imaging <NUM> and the panned region of interest <NUM> of the vessel roadmap <NUM> is carried out through the overlay module.

The computer implemented method <NUM> includes a step <NUM> of displaying the overlay <NUM> from step <NUM> on the display device <NUM>.

In another exemplary embodiment of the present invention, a computer program or a computer program element is provided that is characterized by being adapted to execute the method steps of the method according to one of the preceding embodiments, on an appropriate processing system.

The computer program element might therefore be stored on a computer unit, which might also be part of an embodiment of the present invention. This computing unit may be adapted to perform or induce a performing of the steps of the method described above. Moreover, it may be adapted to operate the components of the above described apparatus. The computing unit can be adapted to operate automatically and/or to execute the orders of a user. The data processor may thus be equipped to carry out the method of the invention.

According to a further exemplary embodiment of the present invention, a computer readable medium is presented wherein the computer readable medium has a computer program element stored on it which computer program element is described by the preceding section.

While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the disclosure as set forth in the appended claims.

Claim 1:
An imaging system (<NUM>) for generating a display including an intravascular device (<NUM>) overlayed on a vessel roadmap (<NUM>), the imaging system comprising:
a data receiver (<NUM>) configured to receive live fluoroscopic imaging (<NUM>) including an intravascular device (<NUM>);
an image processing system (<NUM>) configured to:
receive a vessel roadmap (<NUM>); and
generate a display including the vessel roadmap and the intravascular device overlayed on the vessel roadmap based on the live fluoroscopic imaging;
determine panning data representing a selected region of the vessel roadmap that is panned to match panning of the field of view of the live fluoroscopic images, wherein the panning data is based on a comparison between biological reference markers in the vessel roadmap and the live fluoroscopic imaging; and
pan the display of the vessel roadmap based on the panning data corresponding to panning of a field of view of the live fluoroscopic imaging so that the intravascular device is overlayed at a correct location on the vessel roadmap.