Method and system for visualizing overlapping images

Abstract

A medical imaging workstation and method for visualizing overlapping images are disclosed, the workstation and method comprising accessing a first image data set and a second image data set. The workstation and method comprise displaying a first image on a display device, wherein the first image comprises at least a portion of the first image data set and comprises a structure. The workstation and method comprise displaying a second image on the display device simultaneously with the first image, wherein the second image comprises at least a portion of the second image data set and comprises the structure, and wherein at least a portion of the second image overlaps the first image. The workstation and method comprise automatically cyclically changing the opacity of at least a portion of the second image that overlaps the first image.

Description

Technical Field

[0001] The present disclosure generally relates to a method and a medical imaging workstation for visualizing overlapping images. Background Art

[0002] The present invention relates generally to imaging of objects, and more particularly to visualizing overlapping images.

[0003] In medical imaging, it is often desirable to display two or more overlapping images. For example, when attempting to register a first image with a second image, the two images may be displayed in an overlapping manner. Likewise, a first image containing a first type of data may be displayed overlapping a second image containing a second type of data. The two overlapping images may contain information acquired with different imaging modalities, or the two overlapping images may contain information acquired with different acquisition modes.

[0004] One problem with conventionally displayed overlapping images is that the overlying image at least partially obscures the underlying image. The overlying image makes it more difficult to see the information contained in the underlying image. Or, conversely, if the overlying image is made more transparent, the data contained in the underlying image is more difficult to interpret. It is difficult or impossible to display all the information in both the overlying image and the underlying image using conventional techniques.

[0005] When registering a first image with a second image, the images are typically displayed in an overlapping manner. When registering two images to one another, it is desirable to align common anatomical structures or landmarks between the two images. The process of registering two images typically requires manual input from an operator in order to register the images as closely as possible to one another. However, it is difficult to accurately register the two images to one another when the overlying image obscures a portion of the underlying image. It is difficult for a user to discern the anatomical structures in the overlying image and the underlying image in order to accurately register them to one another.

[0006] Likewise, when the underlying image and the overlying image represent different types of data, it is difficult for a user to interpret all of the data in both the underlying image and the overlying image.

[0007] For at least the reasons discussed above, there is a need for improved methods and workstations for visualizing overlapping images. Summary of the invention

[0008] The above-mentioned shortcomings, disadvantages and problems are addressed herein, which will be understood by reading and understanding the following specification.

[0009] In one embodiment, a method for visualizing overlapping images includes accessing a first image dataset and a second image dataset, wherein the first image dataset and the second image dataset are acquired using one or more medical imaging systems. The method includes displaying a first image on a display device, wherein the first image includes at least a portion of the first image dataset and includes a structure. The method includes displaying a second image on the display device simultaneously with the first image, wherein the second image includes at least a portion of the second image dataset and includes the structure, and wherein at least a portion of the second image overlaps with the first image. The method includes automatically and cyclically changing the opacity of at least a portion of the second image that overlaps with the first image.

[0010] In one embodiment, a medical imaging workstation includes a user input device, a display device, and a processor in electronic communication with the user input device and the display device. The processor is configured to access a first image data set and a second image data set, wherein the first image data set and the second image data set are acquired using one or more medical imaging systems. The processor is configured to display a first image on the display device, wherein the first image includes at least a portion of the first image data set and includes a structure. The processor is configured to display a second image on the display device simultaneously with the first image, wherein the second image includes at least a portion of the second image data set and includes the structure, and wherein at least a portion of the second image overlaps with the first image. The processor is configured to automatically and cyclically change the opacity of at least a portion of the second image that overlaps with the first image.

[0011] Various other features, objects and advantages of the present invention will be apparent to those skilled in the art from the accompanying drawings and detailed description thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a schematic diagram of a workstation according to one embodiment;

[0013] Figure 2 is a schematic diagram of a medical imaging system according to one embodiment;

[0014] Figure 3 is a flow chart of a method according to one embodiment;

[0015] Figure 4 is a representation of the first image, the second image, and the composite image;

[0016] Figure 5 is a representation of a second image overlapping a portion of a first image according to one embodiment;

[0017] Figure 6 is a representation of three composite images generated from a 3D data set according to one embodiment;

[0018] Figure 7 is a graph of a sawtooth function according to one embodiment;

[0019] Figure 8 is a graph of a sine function according to one embodiment;

[0020] Fig. 9 is a graph of a step function according to one embodiment;

[0021] Fig.10 is a representation of a series of screen shots according to one embodiment. DETAILED DESCRIPTION

[0022] In the following detailed description, reference is made to the accompanying drawings which form a part thereof, and in which specific embodiments that can be practiced are shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, and it should be understood that other embodiments may be utilized, and logical, mechanical, electrical and other changes may be made without departing from the scope of the embodiments. Therefore, the following specific embodiments should not be considered to limit the scope of the present invention.

[0023] Figure 1 1 is a schematic diagram of a medical imaging workstation 10 according to an embodiment. The medical imaging workstation 10 includes a display device 12, a user input device 14 and a processor 16. The display device 12 and the input device 14 are both in electronic communication with the processor 16. The display device 12 may be an LED display, an OLED display, a liquid crystal display (LCD), a projection display device, a cathode ray tube monitor or any other type of display configured to display one or more images. The user input device 14 may include any type of user input control, including one or more of the following: a mouse, a trackball, a keyboard, a touchpad, a user interface based on a touch screen, one or more hard buttons, a slider, a rotary member or any other type of physical control. The processor 16 may include one or more of the following elements: a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), a graphics card or any other type of electronic device configured to implement a logic processing instruction. According to various embodiments, the medical imaging workstation 10 may be a stand-alone workstation configured to receive image data from one or more of a memory, a separate medical imaging system and / or a database such as a PACS / RIS system.

[0024] Figure 2is a schematic diagram of a medical imaging system 20. The medical imaging workstation 10 is a component of the medical imaging system 20 according to one embodiment. The medical imaging system 20 also includes an image acquisition unit 22. The medical imaging system 20 may be any type of medical imaging system, such as an x-ray imaging system, a computed tomography (CT) imaging system, a positron emission tomography (PET) imaging system, an ultrasound imaging system, or a single photon computed tomography (SPECT) imaging system. Similarly, the image acquisition unit 22 may be an x-ray acquisition unit, a computed tomography (CT) acquisition unit, a positron emission tomography (PET) acquisition unit, an ultrasound acquisition unit, a single photon computed tomography (SPECT) acquisition unit, or any other type of medical image acquisition unit. The image acquisition unit 22 includes acquisition hardware for acquiring one or more image data sets and a hardware structure for supporting the acquisition hardware. The image acquisition unit may also include one or more processors for controlling the acquisition of image data. According to various embodiments, the processor 16 in the medical imaging workstation may also be used to control the acquisition hardware 24 in the image acquisition unit 22.

[0025] According to an embodiment in which the image acquisition unit 22 is an x-ray acquisition unit, the acquisition hardware 24 may include an x-ray tube and an x-ray detector.

[0026] According to an embodiment where the image acquisition unit 22 is a CT acquisition unit, the acquisition hardware 24 may include one or more x-ray tubes and a CT detector disposed on a gantry configured to rotate around a patient support. The CT detector is configured to detect x-rays emitted by the one or more x-ray tubes.

[0027] According to an embodiment where the image acquisition unit 22 is a PET acquisition unit, the acquisition hardware 24 may include PET detectors disposed about the patient gantry. The PET detectors are sensitive to gamma rays emitted in response to positron annihilation events occurring within the patient.

[0028] According to an embodiment in which the image acquisition unit 22 is a SPECT acquisition unit, the acquisition hardware 24 may include one or more gamma detectors configured to detect gamma rays emitted from the radioactive tracer.

[0029] According to an embodiment in which the image acquisition unit 22 is an ultrasound acquisition unit, the acquisition hardware 24 may include a probe having a plurality of transducer elements, a beamformer, a transmitter, and a receiver.

[0030] Figure 3 is a flow chart of a method 300 according to one exemplary embodiment. The various blocks of the flow chart represent steps that may be performed according to the method 300. Additional embodiments may perform the steps shown in a different sequence, and / or additional embodiments may include Figure 3 The technical effect of method 300 is to periodically change the opacity of at least a portion of an image that overlaps another image so as to more clearly display information in both the overlying image and the underlying image. Figure 1 and Figure 2 The illustrated workstation 10 is described according to an exemplary embodiment.

[0031] At step 302, the processor 16 accesses a first image data set. The first image data set may be acquired with a separate medical imaging system, and the processor 16 may access the first image data set from a memory, the first image data set may be accessed from the separate medical imaging system, or the first image data set may be accessed from a PACS / RIS system. Alternatively, according to an embodiment where the workstation 10 is part of a medical imaging system, such as Figure 2 In the illustrated embodiment, the first image data may be acquired using image acquisition unit 22. According to various embodiments, processor 16 may control the acquisition of the first image data set.

[0032] At step 304, processor 16 accesses the second image data set. The second image data set may be acquired with a separate medical imaging system, and processor 16 may access the first image data set from memory, the separate medical imaging system, or from a PACS / RIS system. Alternatively, according to an embodiment where workstation 10 is part of a medical imaging system, such as Figure 2 In the illustrated embodiment, the second image data set may be acquired using the image acquisition unit 22. According to various embodiments, the processor 16 may control the acquisition of the first image data set. The first image data set and the second image data set may include at least one common structure. For example, one or more anatomical structures included in the first image data set may also be included in the second image data set.

[0033] According to one embodiment, the first image dataset and the second image dataset may be acquired using different medical imaging systems. For example, the first image dataset may be acquired using a medical imaging system selected from an x-ray imaging system, a CT imaging system, a PET imaging system, an ultrasound imaging system, or a SPECT imaging system. The second image dataset may, for example, be acquired using a different type of medical imaging system. For example, the second image dataset may be acquired using an x-ray imaging system, a CT imaging system, a PET imaging system, an ultrasound system, or a SPECT imaging system, wherein the type of medical imaging system used to acquire the second image dataset is different from the type of medical imaging system used to acquire the first image dataset.

[0034] According to some non-limiting examples, x-ray images acquired by an x-ray imaging system, CT images acquired by a CT imaging system, and MR images acquired by an MR imaging system provide images of structures represented within the body. PET images acquired by a PET imaging system and SPECT images acquired by a SPECT imaging system are functional images that provide physiological information about the patient's body. Ultrasound images acquired by an ultrasound imaging system can be used to provide information about structural features or physiological information (such as blood flow, strain, or tissue stiffness) when imaging a patient, as well as to provide other types of information. Both x-ray imaging systems and ultrasound imaging systems can be used to provide real-time images of patients during surgery or examinations. Various different types of imaging systems are sometimes referred to as modalities.

[0035] According to other embodiments, the first image data set and the second image data set may be acquired with the same imaging modality. The first image data set may be acquired using the same or different imaging modes. For example, the first image data set may be an ultrasound imaging data set acquired with a first imaging mode, and the second image data set may be an ultrasound imaging data set acquired with a second imaging mode. Examples of ultrasound imaging modes include: B-mode, M-mode, color Doppler, strain, and elastic imaging. According to an exemplary embodiment, the first image data set may be B-mode ultrasound imaging data, and the second image data set may be color Doppler ultrasound imaging data.

[0036] At step 306, processor 16 displays a first image based on at least a portion of the first image data set on display device 12. And, at step 308, processor 16 displays a second image based on at least a portion of the second image data set on display device 12. On the display device, the second image at least partially overlaps the first image. Steps 306 and 308 may be performed simultaneously.

[0037] Figure 4 is a schematic diagram of how the processor 16 displays both the first image and the second image on the display device 12 simultaneously. Figure 4 A first image 402 generated based on a first image dataset and a second image 404 generated based on a second image dataset are shown. Figure 4 Also shown is a composite image 406 resulting from simultaneously displaying both the first image 402 and the second image 404 on the display device 12. Figure 4In the illustrated embodiment, in composite image 406, second image 404 completely overlaps first image 402. According to other embodiments, in composite image 406, second image 404 only partially overlaps first image 402. For these embodiments, a portion of second image 404 overlaps the first image. According to some embodiments in which the position of second image 404 may be adjusted relative to first image 402, the size and shape of the portion of second image 404 that overlaps first image 402 may change as the position of second image 404 relative to first image 402 is adjusted.

[0038] exist Figure 4 In the illustrated embodiment, area 408 represents the portion of second image 404 that overlaps first image 402. As described above, according to an exemplary embodiment, area 408 represents the entirety of second image 404. For purposes of this embodiment, second image 404 will be referred to as the overlying image, and first image 402 will be referred to as the underlying image.

[0039] Figure 5 A representation of an embodiment is shown, wherein only a portion of the second image 404 overlaps the first image 402 according to one embodiment. Figure 5 4 , a portion 408 of the second image 404 that overlaps with the first image 402 is shown with cross-hatching.

[0040] Figure 6 A representation of a screen shot is shown according to one embodiment, wherein the first image data set is a 3D data set and the second image data set is also a 3D data set. Various embodiments may simultaneously display multiple images representing various slices or planes. Figure 6 Overlapping images from three separate planes or slices within the first image dataset and the second image dataset are included. Figure 6 The images in represent different non-parallel planes, but according to other embodiments, the images may represent two or more planes parallel to each other from within the 3D data set. For example, Figure 6 Included are a first image 402 and a second image 404 and a first overlapping region 408. According to one embodiment, the first image 402 may be a CT image of a short-axis view of the mitral valve, and the second image 404 may be an ultrasound image of a short-axis view of the mitral valve. Figure 6 Included are a third image 422 and a fourth image 424 and a second overlap region 428. According to one embodiment, the third image 422 may be a CT image of a mitral valve-commissure view, and the first image 424 may be an ultrasound image of a mitral valve-commissure view. Figure 6Includes a fifth image 432 and a sixth image 434 and a third overlapping region 438. According to one embodiment, the fifth image 432 may be a CT image of an anterior-posterior long axis view, and the sixth image 434 may be an ultrasound image of an anterior-posterior long axis view. The first image 402, the third image 422, and the fifth image 432 may all be generated by reconstructing plan views or slices from a 3D CT data set. The second image 404, the fourth image 424, and the sixth image 434 may all be generated by reconstructing plan views from a 3D ultrasound data set. It should be understood that according to other embodiments, the images may be generated by reconstructing plan views or slices from different types of 3D data sets. In addition, Figure 6 The depicted views are according to an exemplary embodiment.

[0041] At 310, the processor 16 determines whether the opacity of the second image 404 should be adjusted. According to one embodiment, if the workstation is in a mode that allows automatic changes in opacity, the method 300 proceeds to step 312. According to other embodiments, the user can selectively switch between a mode that automatically changes the opacity of the second image 404 and a mode that does not automatically change the opacity of the second image 404. If it is not desired to adjust the opacity of the second image 404 (i.e., the workstation 10 is in a mode that does not automatically change the opacity of the second image 404), the method 300 proceeds to end at 316.

[0042] If the workstation 10 is in a mode to automatically change the opacity of the second image, the method 300 proceeds to step 312. At step 312, the processor 16 automatically adjusts the opacity of the second image 404, and the second image 404 is displayed on the display device 12 with an opacity different from the opacity of the second image 404 at step 308. The second image 404 may have a uniform or non-uniform opacity. For embodiments in which the second image has a non-uniform opacity, the opacity of the image may still be reduced by a fixed amount or percentage. At step 314, the processor 16 determines whether it is desired to adjust the opacity of the second image. If it is not desired to adjust the opacity of the second image 404, the method proceeds to end at step 316. However, if the workstation 10 is still in a mode to automatically change the opacity of the second image 404, the method returns to step 312, where the opacity of the second image 404 is adjusted. As long as the workstation 10 remains in a mode in which it is desired to automatically change the opacity of the second image 404, the method 300 may iteratively loop through steps 312 and 314. According to some embodiments, the method may iteratively cycle through steps 312 and 314 while the operator is adjusting the position of second image 404 relative to first image 402. Additional description of some exemplary ways in which the opacity of second image 404 may be automatically changed is described below.

[0043] Figure 7 , Figure 8 and Fig. 9 is a graph illustrating the manner in which processor 16 may cyclically vary the opacity of a second image according to various embodiments.

[0044] See also Figure 7 , curve 700 represents opacity values ​​along y-axis 702 and time along x-axis 704. T0, T1, T2, T3, T4, T5, T6, T7, and T8 represent time along x-axis 704. According to one embodiment, time T0, T1, T2, T3, T4, T5, T6, T7, and T8 may represent evenly spaced time intervals. Curve 700 represents a periodically repeated sawtooth function. From time T0 to time T4 represents a period τ or cycle. According to various embodiments, it may be desirable to use a function with a period between 1 second and 20 seconds, but other embodiments may use a function with a period shorter than 1 second or longer than 20 seconds. According to other embodiments, the period may be user-adjustable. Curve 700 shows two complete cycles of the function represented in curve 700.

[0045] according to Figure 7 In the illustrated embodiment, the processor 16 automatically and cyclically changes the opacity of the second image 404 according to the sawtooth function represented by the curve 700. For example, at time T0, the opacity of the second image 404 is O3; at time T1, the opacity of the second image is O2; at time T2, the opacity of the second image 404 is O1; at time T3, the opacity of the second image 404 is O2; and at time T4, the opacity of the second image 404 is O3. As shown in the curve 700, from time T0 to time T2, the processor 16 reduces the opacity of the second image 404 in a linear manner, and from time T2 to time T4, the processor 16 increases the opacity in a linear manner.

[0046] See also Figure 8 , curve 800 represents opacity values ​​along y-axis 702 and time along x-axis 704. T0, T1, T2, T3, T4, T5, T6, T7, and T8 represent time along x-axis 704. According to one embodiment, time T0, T1, T2, T3, T4, T5, T6, T7, and T8 may represent evenly spaced time intervals. Curve 800 represents a sine function. From time T0 to time T4 represents a cycle or loop. According to various embodiments, it may be desirable to use a function with a cycle between 1 second and 20 seconds, but other embodiments may use a function with a cycle shorter than 1 second or longer than 20 seconds. According to other embodiments, the cycle may be user-adjustable. Curve 800 shows two complete cycles of the sine function represented in curve 700.

[0047] according to Figure 8 In the illustrated embodiment, the processor 16 automatically and cyclically changes the opacity of the second image 404 according to the sine function represented by the curve 800. For example, at time T0, the opacity of the second image 404 is O3; at time T1, the opacity of the second image 404 is O2; at time T2, the opacity of the second image 404 is O1; at time T3, the opacity of the second image 404 is O2; and at time T4, the opacity of the second image 404 is O3. In the manner shown by the curve 800, from time T0 to time T2, the processor 16 reduces the opacity of the second image, and from time T2 to time T4, the processor 16 increases the opacity.

[0048] See also Fig. 9 , curve 900 represents opacity values ​​along y-axis 702 and time along x-axis 704. T0, T1, T2, T3, T4, T5, T6, T7, and T8 represent time along x-axis 704. According to one embodiment, time T0, T1, T2, T3, T4, T5, T6, T7, and T8 may represent evenly spaced time intervals. Curve 900 represents a step function. From time T0 to time T4 represents a cycle or loop. According to various embodiments, it may be desirable to use a function with a cycle between 1 second and 20 seconds, but other embodiments may use a function with a cycle shorter than 1 second or longer than 20 seconds. According to other embodiments, the cycle may be user-adjustable. Curve 800 shows two complete cycles of the step function represented in curve 700.

[0049] according to Figure 8 In the illustrated embodiment, the processor 16 automatically and cyclically changes the opacity of the second image 404 according to the step function represented by the curve 800. For example, at time T0, the opacity of the second image is O3, at time T1, the opacity of the second image 404 is O2; at time T2, the opacity of the second image 404 is O1; at time T3, the opacity of the second image 404 is O2; and at time T4, the opacity of the second image 404 is O3. In the step manner shown by the curve 800, from time T0 to time T2, the processor 16 reduces the opacity of the second image 404, and from time T2 to time T4, the processor 16 increases the opacity.

[0050] Curves 700, 800, and 900 are merely three exemplary embodiments of a periodically repeating function that processor 16 may use to automatically change the opacity of second image 404. In other embodiments, processor 16 may automatically and cyclically adjust the opacity of second image 404 according to other functions. Processor 16 may automatically and cyclically change the opacity of second image 404 between a maximum value (such as opacity O3) and a minimum opacity (such as opacity O1), as shown in FIG. Figure 7 , Figure 8 and Fig. 9 As shown. In addition, according to other embodiments, the period of the periodic variation function for controlling the opacity of the second image 404 can be adjusted. The period of the periodic variation function can be adjusted manually, or the period can be automatically adjusted by the processor. For example, the period of the function can be longer over time, or the period of the function can be shorter over time. For example, when performing registration between two or more images, since the needs of the clinician may be different when roughly adjusting the position of the second image 404 relative to the first image 402 and when finely adjusting the position of the second image 404 relative to the first image 402, it may be advantageous to change the period of the function.

[0051] Curves 700, 800 and 900 all share a common period and have the same opacity values ​​at times defined on the x-axis of the graphs. However, in each of the embodiments shown, the manner in which processor 16 controls transitions between times defined on the graphs is different.

[0052] Fig.10 According to one embodiment, the corresponding Figure 7 , 8 9 and 9 show four exemplary screen shots at times T0, T1, T2, and T3. It should be understood that according to other embodiments, processor 16 may display intermediate images. In other words, processor 16 may display one or more images between time T0 and time T1. Processor 16 may display one or more images between time T1 and time T2. Processor 16 may display one or more images between time T2 and time T3. And processor 16 may display one or more images between time T3 and time T4.

[0053] Fig.10 The image 150 corresponding to time T0, the image 152 corresponding to time T1, the image 154 corresponding to time T2, and the image 156 corresponding to time T3 are included. Each of the images 150, 152, 154, and 156 represents a composite image including the first image 402 and the second image 404. Fig.10 In the illustrated embodiment, the second image 404 completely overlaps the first image 402 .

[0054] In image 150, the second image 404 is displayed with an opacity of O3; in image 152, the second image 404 is displayed with an opacity of O2; in image 154, the second image 404 is displayed with an opacity of O1; and in image 156, the second image 404 is displayed again with an opacity of O2. As described above, Fig.10 The opacity of the second image 404 shown may be determined by the processor 16 according to Figure 7 , 8 Or one of 9 graphically represented functions to automatically change. Fig.10 404 within a complete cycle. It should be understood that the processor 16 may continue as follows Fig.10 The opacity of the second image is shown to be automatically adjusted according to the same function and for a period of time longer than one cycle.

[0055] According to many embodiments, the first image 402 and the second image 404 may represent image data acquired from different imaging modalities, or they may represent image data acquired using the same imaging modality in different imaging modes. According to most embodiments, the first image 402 and the second image 404 contain different types of data. To help the clinician distinguish the first image 402 from the second image 404 in the composite image 406, the processor 16 may display the first image data set as a first image using a first color map and display the second image data set as a second image using a second color map that is different from the first color map.

[0056] The processor 16 may also control the opacity (and therefore the transparency) of the second image 404 to enable the clinician to view both the first image 402 and the second image 404 in the area of ​​the second image 404 that overlaps with the first image 402 .

[0057] For example, image 150 shows a composite image at time T0 when the second image is at a maximum opacity level represented by opacity O3. The maximum opacity level (i.e., the minimum transparency level) makes it very easy for a clinician to discern information in the second image 404 at the expense of some information in the first image 402 that is blurred as the underlying image. Image 152 shows the second image 404 at opacity level O2, which represents an opacity level between the maximum opacity level O3 and the minimum opacity level O1. In image 152, the intermediate opacity level O2 enables the clinician to see some information in the first underlying image 402 and some information in the second overlying image 404. According to an exemplary embodiment, image 154 shows the second image 404 at opacity level O1, which represents the minimum opacity level (i.e., the maximum transparency level). The low opacity level enables the clinician to clearly see the structures and / or details represented in the first underlying image 402 in the area overlapping with the second image 404.

[0058] This technique enables the clinician to alternate between clearly viewing all details / structures in the second overlying image 404 and clearly viewing all details / structures in the first underlying image 402 by automatically cyclically changing the opacity of the second image 404. According to other embodiments, the processor 16 may control the display in a manner such that the color map used for the first image 402 or the second image 404 changes periodically while the processor 16 changes the opacity of the second image 404 periodically.

[0059] This written description uses examples to disclose the invention, including the best mode, and also to enable those skilled in the art to practice the invention, including making and using any devices or systems and performing any included methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with minor differences from the literal language of the claims.

Claims

1. A method for visualizing overlapping images, the method comprising: accessing a first image dataset and a second image dataset, wherein the first image dataset and the second image dataset were acquired using one or more medical imaging systems; displaying a first image on a display device, wherein the first image includes at least a portion of the first image data set and includes a structure; displaying a second image on the display device simultaneously with the first image, wherein the second image comprises at least a portion of the second image data set and includes the structure, and wherein at least a portion of the second image overlaps the first image; as well as Automatically cyclically changing the opacity of at least the portion of the second image overlapping the first image and adjusting the position of the second image relative to the first image to align the first image with the second image, wherein the opacity of at least the portion of the second image automatically cyclically changes according to a periodically repeating function, wherein the period of the function is different when coarsely adjusting the position of the second image relative to the first image and when finely adjusting the position of the second image relative to the first image. 2 . The method of claim 1 , wherein automatically cyclically changing the opacity of at least the portion of the second image comprises automatically cyclically changing the opacity of the entire second image.

3. The method of claim 1, wherein automatically cyclically changing the opacity of at least the portion of the second image comprises automatically cyclically changing the opacity of the portion of the second image that overlaps with the first image, and not automatically cyclically changing the opacity of the portion of the second image that does not overlap with the first image.

4. The method according to claim 1, wherein the first image data set includes first ultrasound image data acquired from a first ultrasound imaging mode, and the second image data set includes second ultrasound image data acquired from a second ultrasound imaging mode, and wherein the second ultrasound imaging mode is different from the first ultrasound imaging mode. 5 . The method according to claim 4 , wherein the first ultrasound imaging mode is a B-mode and the second ultrasound imaging mode is a color Doppler mode, and wherein the first ultrasound image data and the second ultrasound image data are acquired in an interleaved manner.

6. The method of claim 1 , wherein the one or more medical imaging systems used to acquire the first image data set are selected from: a computed tomography imaging system, an ultrasound imaging system, a positron emission tomography imaging system, a nuclear medicine imaging system, and an x-ray imaging system.

7. The method of claim 6, wherein the one or more medical imaging systems used to acquire the second image data set are selected from: a computed tomography imaging system, an ultrasound imaging system, a positron emission tomography imaging system, a nuclear medicine imaging system, and an x-ray imaging system.

8. The method of claim 7, wherein the one or more medical imaging systems used to acquire the second image dataset are different from the one or more medical imaging systems used to acquire the first image dataset.

9. The method of claim 1, wherein at least one of the first image data set and the second image data set is acquired in real time.

10. The method of claim 1, wherein the portion of the second image has a non-uniform opacity.

11. The method of claim 1, wherein the portion of the second image has a uniform opacity.

12. The method of claim 1, wherein the periodically repeating function is selected from the group consisting of a sine function, a step function, and a sawtooth function.

13. The method of claim 12, wherein the function has a period between 1 second and 20 seconds. The method of claim 13 , wherein the period is user adjustable.

15. The method of claim 1 further comprising displaying the first image using a first color map and displaying the second image using a second color map different from the first color map to help distinguish the first image from the second image.

16. The method of claim 1, further comprising automatically cyclically changing a color map between a first color and a second color as said automatically cyclically changing said opacity of said second image.

17. The method of claim 1, wherein the first image dataset is a first 3D dataset and the second image dataset is a second 3D dataset, and wherein the first image is a first slice rendered from the first 3D dataset and the second image is a second slice rendered from the second 3D dataset.

18. The method according to claim 17, further comprising: displaying a third image from the first image dataset on the display device concurrently with the first image and the second image and displaying a fourth image from the second image dataset on the display device, wherein the third image is a second slice rendered from the first image dataset and the fourth image is a second slice rendered from the second image dataset, wherein a portion of the fourth image at least partially overlaps the third image; as well as The opacity of at least the portion of the fourth image overlapping with the third image is automatically and cyclically changed therebetween, wherein the automatic and cyclical changing of the opacity of at least the portion of the fourth image is synchronized with the automatic and cyclical changing of the opacity of at least the portion of the second image.

19. A medical imaging workstation, comprising: User input devices; Display devices; and a processor in electronic communication with the user input device and the display device, wherein the processor is configured to: accessing a first image dataset and a second image dataset, wherein the first image dataset and the second image dataset were acquired using one or more medical imaging systems; displaying a first image on the display device, wherein the first image includes at least a portion of the first image data set and includes a structure; displaying a second image on the display device simultaneously with the first image, wherein the second image includes at least a portion of the second image data set and includes the structure, and wherein at least a portion of the second image overlaps the first image; as well as automatically and cyclically changing the opacity of at least the portion of the second image that overlaps the first image and adjusting the position of the second image relative to the first image to register the first image with the second image, wherein the processor is configured to cyclically vary the opacity of at least the portion of the second image according to a periodic function, wherein the period of the function is different when the position of the second image is coarsely adjusted relative to the first image and when the position of the second image is finely adjusted relative to the first image.

20. The medical imaging workstation of claim 19, wherein the medical imaging workstation is a component of a medical imaging system.

21. The medical imaging workstation of claim 19, wherein the medical imaging workstation is a component of an ultrasound imaging system.

22. The medical imaging workstation of claim 19, wherein the processor is configured to display the first image using a first color map and to display the second image using a second color map, wherein the second color map is different from the first color map.

23. The medical imaging workstation of claim 19, wherein the processor is configured to periodically change a color map of the second image between a first color and a second color as the opacity periodically varies, wherein the first color is different from the second color.

Images