CN1849624A - System and method for spatio-temporal modeling using guidepoints - Google Patents

Abstract

A method and system for spatio-temporal (4D) modeling of an object includes sampling the 4D model at one point in time to create a 3D model. This 3-D model is then fit based on user-supplied guide points, image forces (e.g., image edges) and prior shape models. Once the 3D model fit is completed the full 4D shape model is updated. Cardiac images can be spatio-temporally modeled to determine LV conditions.

Description

Be used to utilize guiding point to carry out time and space system for modeling and method

The cross reference of related application

It is the U.S. Provisional Application No.60/501 of " Spatio-TemporalGuide Point Modeling for Fast Analysis of Four-DimensionalCardiac Function (being used for the time and space guiding point modeling of the express-analysis of four-dimensional cardiac function) " that the application requires in the title that on September 10th, 2003 submitted to, 629 rights and interests are incorporated herein by reference in this content with this application.

Technical field

The present invention relates to electronic imaging, and relate more specifically to utilize the medical imaging of room and time parameter.

Background technology

The medical imaging field has experienced many progress recently.Equipment such as CT (computer tomography) scanning, MRI (medical science resonance image-forming) is a few of this progress.When the equipment of making renewal has been an important goal, can be considered to target of equal importance to the needs of analyzing the data of catching effectively by this equipment.

It is in cardiovascular imaging field that the typical case of medical imaging uses, and is not having in this field under the situation of suitable medical imaging technology, and it is extremely dangerous that the diagnosis of cardiovascular problems and operation will become.The medical imaging of heart especially focuses on left ventricle (LV).The function of LV has primary importance for the cardiologist, because it is to be responsible for the chamber of blood pump to body extremity.

Medical imaging can produce a large amount of images, and therefore makes the analysis of this image become challenging task.For example, be used for determining that the typical mr I of LV situation scans the mass data collection that can cause comprising images up to a hundred.The time response of LV function is widely used in the clinical practice, so that diagnosis, prediction and assess cardiac are shunk and the diastole dysfunction.

In order to cut apart LV, should find its border.In case the border is found, the doctor just can for example measure the health status how much blood LV can aspirate and determine LV.Have the robot brain visible sensation method that is used for detection boundaries, but they are easy to occur error.Therefore this correction of cutting apart error automatically is time-consuming task, and becomes unrealistic along with the increase of the quantity of image (and error).Therefore, need a kind of time coherence analytical approach, wherein user interactions is real-time, effective, directly perceived and MIN.

By convention, the 3D modeling of cardiac image is included in obtains cardiac image in cardiac cycle, and then with the 3D model fitting to the dirty border of picture centre.This process comprises draws profile and each interior independent stage of match cardiac cycle of describing the border.This is the extremely intensive task of working.The semi-automatic technology that is used for draw outline has been quickened task a little, but because needs were confirmed and correction cutting apart of obtaining, this also is time-consuming.Therefore, need a kind of modeling technique, it requires MIN artificial modeling input and relatively error free.

Summary of the invention

The time and space method and system that is used for modeling is disclosed.The territory is the 4D view data, i.e. 3D rendering volume on discrete time point (stage).Therefore, our model is 4D (the 3D+ time), and the 3d space model that can be used as on the special time example is sampled.User and the 3D model reciprocation of being sampled are because the people is difficult to directly more working in the higher-dimension.Influence the 3D model fitting by guiding point that the user placed on the image of moment and image edge information.The characteristic of this 3D model is propagated, to influence the 4D model in the nigh stage on the whole.

Because the motion of heart is periodic, be used to describe the 4D model so ball is humorous.More specifically, utilize harmonic wave to represent to describe the parameter of shape, so that the 3D example of this model when cardiac cycle begins is identical with 3D example when finishing.

By being the continuous function of time with parametric representation, model is 4D.And influence whole 4D shape with the match and the image force on a time point (stage) of guiding point.For the reason of efficient, before this influence was transmitted to other stage, the user finished the match in 3D model and stage.

Do not having in the stage of guiding point, having prior shape based on the 4D model.If the user is chosen on this stage guiding point is set, then this prior shape also can be used to influence this match.

Therefore, elimination is with the needs of each model and each stage match.On the contrary, guiding point is set and will produce match with whole cardiac cycle in a few stage.Typical application is a cardiac imaging, wherein the 4D model of match heart during comprising the stage of cardiac cycle.

Description of drawings

Describe the preferred embodiments of the present invention with reference to the accompanying drawings, wherein:

Fig. 1 is the expression of the left ventricle of heart;

Fig. 2 illustrates time-parametric line;

Fig. 3 A is the exemplary model of heart;

Fig. 3 B is another view of this cardiac module;

Fig. 3 C illustrates the exemplary guiding point of the 3D example that is used to handle this model;

Fig. 3 D is the top view of the profile in this model;

Fig. 3 E illustrates the curve map of volume (Y-axis) to time/stage (X-axis);

Fig. 3 F illustrates the 3-D view of the iconic model that is used for exemplary heart;

Fig. 4 A is illustrated in the guiding point curve map of parameter before is set on the stage t;

Fig. 4 B is illustrated in the spatial fit that stage t goes up model;

Fig. 4 C illustrates the time match of 4D model;

Fig. 5 illustrates the process flow diagram that time and space is handled in the embodiments of the invention;

Fig. 6 is the exemplary block diagram that is used to implement the time and space system for modeling in an embodiment of the present invention;

Fig. 7 is the calcspar that is used to implement illustrative computer system of the present invention.

Embodiment

The preferred embodiments of the present invention are described with reference to the accompanying drawings.

Following description adopts the example of health that at least one embodiment of the present invention is described.The example that is adopted is the example of human heart.Those skilled in the art will appreciate that heart only is used as explanation, and the explanation of replacement heart can be carried out modeling to any other body part, tissue and organ.

Fig. 1 is the expression of the exemplary left ventricle (LV) of heart.Show the schematically showing ofleft ventricle 10 of exemplary heart organ.The outer wall 12 (external membrane of heart) ofleft ventricle 10 is shown as and surrounds inwall 14 (internal membrane of heart).In at least one embodiment of the present invention, with electronic form the scanning electron image ofleft ventricle 10 is carried out modeling.Model is described below.

The 3D example of this model can be described by two surfaces of bicubic spline dough sheet of expression inner and outer wall.These are connected linearly, to form the 3D finite element.The reference mark of these battens is model parameters.In order to obtain model 4D, the reference mark becomes the function of time.

Fourier basis functions with quintuple harmonics was used to provide effective resolution for model in cardiac cycle.Because cardiac cycle comes down to repetition, so the final stage of cardiac cycle is similar to the phase one of next cardiac cycle.Quintuple harmonics can provide enough resolution for this model.

Fig. 2 illustrates time-parametric line.The parameter value of the LV model above describing changed in cardiac cycle.Curve 16-20 shows the variation of n parameter.Utilize harmonic wave to describe these curves.Various different parameters can be used to describe the LV model and change in model in the given time cycle.In our situation, they are batten reference mark.

Fig. 3 A is the exemplary model of heart.Fig. 3 B is another view of this cardiac module.Fig. 3 C illustrates the exemplary guiding point that is used to handle this model.Fig. 3 D is the top view of the xsect of this model.Fig. 3 E illustrates the curve map of volume (Y-axis) to time/stage (X-axis).Model view 22 is calculating 3D examples of this model.Thebottom row 24 of this model is corresponding to the plane of delineation atmiddle row 26 places.Thexsect 30 expression internal membranes of heart (inwall), and thexsect 32 expression external membranes of heart (outer wall).Model view 38 has two axles 42 and 44.If cut heart open at axle 42 and 44 places, then the plane of delineation will be corresponding to middle row 34.

Typically display model view on the display device of medical imaging devices will be connected to.This display device can comprise the equipment that is similar to indicator, and the described equipment that is similar to indicator allows user's adjustment profile with model of fit.For example, Fig. 3 B illustrates four exemplary guiding point.Guiding point 40 and 42 is the guiding point that are used to make model and internal membrane of heart match.Similarly, guiding point 44 and 46 is used to make model and external membrane of heart match.By changing the position of guiding point 40-46, match 32 and 30 profile again.Reflected this variation in the top view of the profile in Fig. 3 D.

Fig. 3 A-3D is illustrated in the different views of this model on the different phase.In addition, these views are represented the different stage (time point).For example, Fig. 3 A is the view of this model on the 5th stage, and Fig. 3 C is the view of this model on the 8th stage.

Fig. 3 E illustrates the curve map of volume (Y-axis) to time/stage (X-axis).As from this curve map as can be seen, greater than the volume on the 8th stage, this volume descends before the mid point of cardiac cycle greatly at the volume of heart on the 5th stage.The application of the curve map above the following declarative description.Utilize this curve map, the doctor can determine the blood flow volume that is pumped to heart and pumps from heart on the given stage, and therefore determines the function of LV.

Fig. 3 F illustrates the 3-D view of the iconic model that is used for exemplary heart.Profile is illustrated as concentric ring, and the plane of delineation illustrates with symbolic form.Illustration on the single stage (instanitaed) 4D model is to form the 3D model.Show endocardial surface.Epicardial surface is not shown; Yet, demonstrate this surface and intersecting from the plane of delineation of importing data.In addition, show in those imaging surfaces two.

Under the influence of set guiding point of marginal information that image is derived and user and prior model (if existence), make the 3D model deformation of the LV geometric configuration of each frame.After finishing each guiding point of editor, utilize to have the model parameter of the Fourier basis functions match in time of quintuple harmonics from all frames.The time match result is used as spatial prior, and the Flame Image Process and the user in the stage that does not have guiding point that are used for subsequently edit.

The modeling that is used for the time and space modeling allows the user to interrupt, and therefore before variation was transmitted on every side frame, the user can carry out some changes to present frame.Provide feedback about convergence process to the interactive plot of time for the user via volume and quality.

Because along with variation is transmitted to all stages, all stages of any motion could affect in the stage in office are so pure 4D model is expensive on calculating.Yet, in the time and space model, match 3D model on the selected stage, and via the humorous parameter that is used to describe the 3D model of propagating of aforesaid ball.

Fig. 4 A is illustrated in the guiding point curve map of parameter before is set on the stage t.Fig. 4 B is illustrated in the spatial fit that stage t goes up this model.Fig. 4 C shows the time match of this model.Form with curve map in Fig. 4 A-4C shows exemplary of parameters.In Fig. 4 A, show exemplary guiding point be set up and parameter influenced before the curve map of parameter.In Fig. 4 B, guiding point realizes " spatial fit " (just in this temporal match) on stage t.As shown in Fig. 4 C, by utilizing the humorous adjustment profile in time of ball, so that influence position 4D model on stage At All Other Times based on the previous spatial fit that realizes.Therefore, by the time and space match that the MIN artificial input of handling single guiding point on the single stage comes implementation model, be adjusted in the 4D model on stage At All Other Times simultaneously automatically.

Fig. 5 illustrates the process flow diagram that the time and space in the embodiments of the invention is handled.Flow process 50 illustrates the operation steps of enforcement based on the modeling process of time and space guidingpoint.In step 52, the user locatees at least one guiding point on the moment ofmodel.In step 54, when the position of regulating guiding point by the user makes model fitting guiding point on this stage, implementation space match (referring to Fig. 4B).In step 56, when being conditioned with this model of match, realize time match (referring to Fig. 4 C) in all other stages.Time-volume curve (referring to Fig. 3 E) is updated instep 58, and this process is repeated, and till this match is stable, wherein reaches match when adding the not obvious change volume of more guiding point-time curve and stablizes.

Fig. 6 is the exemplary block diagram that is used to implement the time and space system for modeling in an embodiment of the present invention.Thissystem 60 comprises user's guiding point input model, and it allows user interactions ground on the suitable stage guiding point to be set.Spatial fit model 64 allows the user to make this stage and guiding point spatial fit as mentioned above.Thereafter, intime match module 66, by carrying out the time match in this stage for the position of other stage this model ofinterpolation.Controller 68 provides the necessary control function, to coordinate other module and user interaction device 70.In addition, display and (unshowned) other output device can be comprised, with the display image model and carry out the guiding point modeling.Output device can be further used in and show the curve (referring to Fig. 3 E) of volume/mass to the time.

With reference to Fig. 7,, be used to implement computer system 101 of the present invention and especially can comprise CPU (central processing unit) (CPU) 102, storer 103 and I/O (I/O) interface 104 according to embodiments of the invention.Computer system 101 is coupled to display 105 by I/O interface 104 and usually such as the various input equipments 106 of mouse and keyboard.Support circuit can comprise circuit such as cache memory, power supply, clock circuit and communication bus.Storer 103 can comprise random-access memory (ram), ROM (read-only memory) (ROM), disc driver, tape drive etc. or its combination.The present invention can be used as be stored in the storer 103 and implement by the routine that CPU 102 carries out, to handle signal from signal source 108.Similarly, computer system 101 is general-purpose computing systems, and when carrying out routine 107 of the present invention, this general-purpose computing system becomes the present invention.

Computer platform 101 also comprises operating system and micro-instruction code.In these described various processing and function can be the part of micro-instruction code or the part of application program (or its combination), wherein carries out this application program by operating system.In addition, various other peripherals, can be connected to computer platform such as additional data storage device and printing device.

What should be further understood that is, because can implement the parts of the composition system described in the accompanying drawing and some in the method step, so the actual connection between the system unit (or treatment step) can depend on mode that the present invention is programmed and difference with software.Be given in the instruction of the present invention that this provides, the those of ordinary skill in the association area can imagine of the present invention these with similar embodiment or configuration.

Though specifically illustrate and described the present invention with reference to one exemplary embodiment of the present invention, but what one skilled in the art should appreciate that is, not breaking away under the situation of the spirit and scope of the present invention as defined by the appended claims, can aspect form and details, carry out various changes at that time.

Though specifically illustrate and described the present invention with reference to one exemplary embodiment of the present invention, but what one skilled in the art should appreciate that is, not breaking away under the situation of the spirit and scope of the present invention as defined by the appended claims, can aspect form and details, carry out various changes at that time.

Claims (15)

1, a kind of time and space system for modeling that is used for object, this system comprises:

The guiding point load module is used for receiving at least one guiding point position as input on the phase one, this phase one is corresponding to one in a plurality of stages of the 4D iconic model of described object;

The spatial fit module is used for the 3D example of match 4D model on corresponding to the phase one of guiding point; And

The time match module is used to make described 4D model and all stage matches.

2, the system of claim 1 further comprises:

User input device is used to receive the guiding point position by user's input.

3, the system of claim 2 further comprises:

Controller is used to receive from least one user of described user input device and interrupts, and changes described guiding point position before in described time match module the spatial fit of phase one being transmitted to all stages.

4, the system of claim 3 further comprises:

Output device is used to show the curve map with the volume of time correlation.

5, the system of claim 4, wherein, along with described curve map is upgraded in the variation of described iconic model in real time.

6, the system of claim 4, wherein, with the state notifying user of convergence process, wherein under convergence state, when the quantity of guiding point increased, it is identical that described curve map keeps basically.

7, by machine-readable program storage device, visibly comprise program by the executable instruction of machine, be used for the method step of the time and space modeling of object with execution, this method step comprises:

Receive the guiding point position as input from the user;

The spatial fit module is used for the 3D example of match 4D model on corresponding to the stage of guiding point; And

The time match module is used to make described 4D model and all stage matches.

8, the method for claim 7 further comprises:

Receive the guiding point position of importing by the user by user input device.

9, the method for claim 8 further comprises:

Reception is interrupted from least one user of described user input device, changes described guiding point position before in the time match step spatial fit of phase one being transmitted to all stages.

10, the method for claim 8 further comprises:

The curve map of the volume of demonstration and time correlation on output device.

11, the system of claim 8, wherein, along with curve map is upgraded in the room and time variation of described iconic model in real time.

12, the method for claim 11, wherein, with the state notifying user of convergence process, wherein when the quantity of guiding point increased, it is identical that described curve map keeps under convergence state basically.

13, a kind of method that is used for the four-dimensional time and space modeling of object, this method comprises:

Obtain the image on a plurality of time phases;

Form the 4D model of described object;

Receive at least one guiding point as input, so that described model and selected phase one match from a plurality of stages from the user;

The 3D example of the described 4D model of match on corresponding to the phase one of described guiding point; And

Based in a stage to the change of described model, the described 4D model of match on all stages.

14, the method for claim 13, wherein said image is a cardiac image.

15, the method for claim 14, wherein the step of the described 4D model of match comprises:

Utilize that ball is humorous will to be inserted in all stages in the iconic model of institute's match on the phase one.

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