Systems and methods for color maps of contrast images

Abstract

Systems and methods for visualizing time-varying two-dimensional (2D) color maps are disclosed. The 2D color map may include luminance values ​​corresponding to hues of varying intensities that change over time. In some 2D color maps, the hue used for the intensity scale may change over time, while the luminance of the pixels may remain constant. In some 2D color maps, both hue and luminance may change over time relative to intensity.

Description

Technical Field

[0001] This application relates to contrast-enhanced imaging. More specifically, this application relates to the mapping of contrast-enhanced images, such as color maps. Background Technology

[0002] In contrast-enhanced ultrasound (CEUS) imaging, the tissue of interest is scanned using a microbubble-specific ultrasound imaging modality while an intravenous bolus of ultrasound contrast agent is administered to the patient. Ultrasound images are acquired as the contrast agent washes in and out of the lesion over the duration of the bolus. Typically, image acquisition parameters are maintained for the entire sequence. An elapsed time display on the screen can be activated while the bolus is being injected to provide an indication of the time between injection and image acquisition. The wash-in and wash-out patterns of the contrast agent in the lesion can provide information for clinical diagnosis in some applications. The images can be viewed as a sequence that allows clinicians or other users to observe the wash-in and wash-out of the contrast agent (e.g., a cine loop). Clinical images can be provided in grayscale or other monochrome (e.g., sepia), where the brightness of a pixel in the image corresponds to the intensity of the ultrasound signal acquired at the location corresponding to that pixel. Figure 8 An example of a 1D color map 800 that correlates ultrasound signal intensity with pixel brightness in an image is shown. Summary of the Invention

[0003] A system and method for providing a two-dimensional (2D) color map are disclosed, which can provide information about multiple parameters related to contrast imaging. Unlike mapping a single parameter, the system and method can display multiple parameters in a single color map using combinations of hue and / or intensity that can change over time. The multiple parameters in a single 2D color map can include time of arrival, time of flight, microbubble concentration, flow rate, and / or perfusion rate.

[0004] According to at least one example disclosed herein, an ultrasound imaging system may include: an ultrasound probe configured to receive ultrasound signals to generate a sequence of ultrasound images; and a processor configured to apply a time-varying color map to represent the intensity of the ultrasound signals in the sequence, wherein the time-varying color map includes a two-dimensional (2D) color map that associates a given intensity of the ultrasound signal with at least one of a brightness value or a hue value that varies over time, and generates individual ultrasound images of the sequence for display by assigning different brightness or hue values ​​to pixels representing ultrasound signals of the same intensity acquired at different time points according to the time-varying color map.

[0005] According to at least one example disclosed herein, a method may include receiving a series of ultrasound images, wherein each image in the sequence of ultrasound images is acquired at different time points, a time-varying color map is applied to individual ultrasound images in the sequence, wherein the time-varying color map comprises a two-dimensional (2D) color map that associates a given intensity of an ultrasound signal with at least one of a brightness value or a hue value that varies over time, and wherein applying the time-varying color map comprises: assigning different values ​​of at least one of the brightness value or hue value to pixels representing ultrasound signals of the same intensity acquired at different time points for individual images in the sequence, and displaying the sequence of ultrasound images.

[0006] According to at least one example disclosed herein, a non-transient computer-readable medium may include instructions that, when executed, cause an ultrasound imaging system to receive a sequence of ultrasound images, wherein each image in the sequence of ultrasound images is acquired at different time points, a time-varying color map is applied to individual ultrasound images in the sequence, wherein the time-varying color map comprises a two-dimensional (2D) color map that associates a given intensity of an ultrasound signal with at least one of a brightness value or a hue value that varies over time, and wherein applying the time-varying color map comprises, for individual images in the sequence, assigning different values ​​of at least one of the brightness value or hue value to pixels representing ultrasound signals of the same intensity acquired at different time points, and displaying the sequence of ultrasound images. Attached Figure Description

[0007] Figure 1A and Figure 1B This is an example of a two-dimensional color map based on the principles of this disclosure.

[0008] Figure 2 This is a block diagram of an ultrasound imaging system arranged according to some examples of this disclosure.

[0009] Figure 3 This is a block diagram illustrating an example processor based on some of the examples disclosed herein.

[0010] Figure 4A This is an example contrast-enhanced ultrasound image of the liver generated using 1D color mapping.

[0011] Figure 4B This is an example contrast-enhanced ultrasound image of the liver generated using a two-dimensional color map according to an embodiment of the present disclosure.

[0012] Figure 5A This is an example contrast-enhanced ultrasound image of the thyroid gland generated using 1D color mapping.

[0013] Figure 5B This is an example contrast-enhanced ultrasound image of the thyroid gland generated using a two-dimensional color map according to an embodiment of this disclosure.

[0014] Figure 6A This is an example contrast-enhanced ultrasound image of the liver generated using 1D color mapping.

[0015] Figure 6B This is an example contrast-enhanced ultrasound image of the liver generated using a two-dimensional color map according to an embodiment of the present disclosure.

[0016] Figure 7 This is a flowchart of a method according to an embodiment of the present disclosure.

[0017] Figure 8 It is a 1D color image. Detailed Implementation

[0018] The following description of specific exemplary embodiments is merely illustrative in nature and is in no way intended to limit the invention or its application or use. In the following detailed description of embodiments of the system and method, reference is made to the accompanying drawings, which form a part of the description, and in which specific embodiments of the described system and method are illustrated by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the currently disclosed systems and methods, and it should be understood that other embodiments may be utilized and structural and logical changes may be made without departing from the spirit and scope of the system. Furthermore, for clarity, detailed descriptions of certain features will not be discussed where obvious to those skilled in the art, so as not to obscure the description of the system. Therefore, the following detailed description should not be regarded in a limiting sense, and the scope of the system is defined only by the claims.

[0019] As previously mentioned, colormaps with fixed hues are used to color-code ultrasound signal intensity in CEUS imaging by brightness (e.g., low intensity represented by black pixels, medium intensity by gray pixels, and high intensity by white pixels). Colormaps can also use a fixed set of hues to color-code ultrasound intensity in CEUS imaging (e.g., low intensity represented by blue pixels, medium intensity by yellow pixels, and high intensity by red pixels). In either case, the colormap is generally not time-varying. That is, for all images in the sequence, the mapping from signal intensity to brightness or hue is fixed over time. In other words, the colormap is one-dimensional (1D). Therefore, it is impossible to fully visualize certain features of the time-varying sequence. For example, for some organs, such as the liver, there are different enhancement phases: the arterial phase, the portal venous phase, and the parenchymal phase. In liver CEUS imaging, the contrast agent tends to saturate some time after perfusion through the organ. In the late arterial phase of liver imaging, arteries and branches become difficult to distinguish due to contrast saturation in the microvascular system.

[0020] Some imaging systems provide parametric displays of contrast images, calculating and displaying peak time, arrival time, washout rate, etc., to the user. 1D color maps are not suitable for time-varying parametric imaging and may require various thresholding steps using modified 1D color maps. Therefore, improved visualization of CEUS imaging is desired.

[0021] Based on the principles of this disclosure, time-varying two-dimensional (2D) color maps can be used to visualize CEUS image sequences or other image sequences. In some examples, a single color, referred to as hue, can be used for similar purposes. Figure 8 The intensity scale of the 1D color map 800 is shown. However, unlike the 1D color map, the luminance values ​​of the hues corresponding to different intensities change over time. In some examples, the hue used for the intensity scale may change over time. That is, while the luminance of a pixel may not change over time relative to intensity, the hue of the pixel may change over time. In still other examples, both hue and luminance may change over time relative to intensity.

[0022] Figure 1A and 1B This is an example of a 2D color image based on the principles of this disclosure. Figure 1A This is a 2D colormap 100A, which comprises a single hue with an intensity scale that changes over time. At early time points, high-intensity ultrasound signals correspond to bright pixels (e.g., white or near-white). Over time, high-intensity ultrasound signals correspond to increasingly darker pixels (e.g., gray or sepia shadows). During CEUS imaging, at early time points, very little contrast agent reaches or accumulates in the organ of interest. Therefore, the ultrasound signal intensity induced by the contrast agent will be low over most (if not all) areas of the ultrasound image. Consequently, the number of pixels at the peak of the intensity colormap (e.g., white) will be low and may not impede the user's ability to view other areas of the organ. Over time, more contrast agent may reach and / or accumulate in the organ, and the ultrasound signal intensity due to the contrast agent may increase. If the colormap remains constant, more areas of the image will include pixels at the colormap peak, causing saturation, which may inhibit the user's ability to view other areas of the organ (e.g., saturation in tissue may prevent the viewing of smaller blood vessels within tissue).

[0023] Figure 1BThis is a 2D color map 100B that includes an intensity scale that varies in hue over time. At early time points, high-intensity ultrasound signals correspond to bright pink pixels, and low-intensity ultrasound signals correspond to dark pink or black pixels. As time progresses, the intensity scale changes from purple to blue and then to blue-green. At later time points, high-intensity ultrasound signals correspond to bright blue-green pixels, while low-intensity ultrasound signals correspond to dark blue-green or black pixels. The hue that varies in intensity level over time allows users to visualize when ultrasound signals from contrast agent in different regions of an organ reach their intensity levels. That is, different hues allow users to identify which regions of an organ first receive and / or accumulate contrast agent, for example, to determine arrival time. Different hues and / or different combinations of hues with brightness can allow users to identify the regions where the contrast intensity of an organ first reaches its peak, for example, to determine peak time. Using the example 2D color map 100B, organ regions receiving and / or accumulating contrast agent during early time points may appear pink, while organ regions receiving and / or accumulating contrast agent during later time points may appear blue-green.

[0024] Figure 2 The diagram illustrates a block diagram of an ultrasound imaging system 200 constructed according to the principles of this disclosure. The ultrasound imaging system 200 according to this disclosure may include a transducer array 214, which may be included in an ultrasound probe 212, such as an external or internal probe, for example, an intravascular ultrasound (IVUS) catheter probe. In other examples, the transducer array 214 may be in the form of a flexible array configured to conformally apply to the surface of the object to be imaged (e.g., a patient). The transducer array 214 is configured to emit ultrasound signals (e.g., beams, waves) and receive echoes (e.g., received ultrasound signals) in response to the emitted ultrasound signals. Various transducer arrays may be used, such as linear arrays, curved arrays, or phased arrays. The transducer array 214 may, for example, include a two-dimensional array (as shown) of transducer elements capable of scanning in the height and azimuth dimensions for 2D and / or 3D imaging. As is well known, the axis is the direction perpendicular to the array plane (in the case of a curved array, the axis fans out), the azimuth direction is usually defined by the longitudinal dimension of the array, and the elevation direction is transverse to the azimuth direction.

[0025] In some examples, transducer array 214 may be coupled to microwave beamformer 216, which may be located within ultrasonic probe 212, and which may control the transmission and reception of signals by the transducer elements in array 214. In some examples, microwave beamformer 216 may control the transmission and reception of signals by active elements in array 214 (e.g., an active subset of array elements that defines the active aperture at any given time).

[0026] In some examples, microwave beamformer 216 may be coupled, for example via a probe cable or wirelessly, to transmit / receive (T / R) switch 218, which switches between transmitting and receiving and protects main beamformer 222 from high-energy transmitted signals. In some examples, such as in portable ultrasound systems, T / R switch 218 and other components of the system may be included in ultrasound probe 212 rather than in an ultrasound system base, which may house image processing electronics. An ultrasound system base typically includes software and hardware components, including circuitry for signal processing and image data generation, and executable instructions for providing a user interface.

[0027] Under the control of microwave beamformer 216, the transmission of ultrasonic signals from transducer array 214 is guided by transmission controller 220, which can be coupled to T / R switch 218 and main beamformer 222. Transmission controller 220 can control the direction in which the beam is steered. The beam can be steered vertically forward from transducer array 214 (perpendicular to transducer array 26), or at different angles for a wider field of view. Transmission controller 220 can also be coupled to user interface 224 and receive input based on user operations on user controls. User interface 224 may include one or more input devices, such as control panel 252, which may include one or more mechanical controls (e.g., buttons, encoders, etc.), touch-sensitive controls (e.g., touchpad, touchscreen, or similar), and / or other known input devices.

[0028] In some examples, the partially beamformed signal generated by microwave beamformer 216 can be coupled to beamformer 222, where partially beamformed signals from individual facets of transducer elements can be combined into a fully beamformed signal. In some examples, microwave beamformer 216 is omitted, and transducer array 214 is under the control of beamformer 222, with beamformer 222 performing all beamforming of the signal. In examples with and without microwave beamformer 216, the beamformed signal from beamformer 222 is coupled to processing circuitry 250, which may include one or more processors (e.g., signal processor 226, mode-B processor 228, Doppler processor 260, and one or more image generation and processing units 268) configured to generate an ultrasound image based on the beamformed signal (i.e., beamformed RF data).

[0029] Signal processor 226 can be configured to process received beamformed RF data in various ways, such as bandpass filtering, decimation, I and Q component separation, and harmonic signal separation. Processor 226 can also perform signal enhancement, such as ripple reduction, signal recombination, and electronic noise cancellation. The processed signals (also referred to as I and Q components or IQ signals) can be coupled to additional downstream signal processing circuitry to generate an image. IQ signals can be coupled to multiple signal paths within the system, each signal path potentially associated with a specific arrangement of signal processing components suitable for generating different types of image data (e.g., B-mode image data, Doppler image data). For example, the system may include a B-mode signal path 258 that couples signals from signal processor 226 to B-mode processor 228 to generate B-mode image data.

[0030] The B-mode processor 228 can employ amplitude detection to image structures in the body. According to the principles of this disclosure, the B-mode processor 228 can generate signals for tissue images and / or contrast images. The signals generated by the B-mode processor 228 can be coupled to a scan converter 230 and / or a multi-plane reformer 232. The scan converter 230 can be configured to arrange the echo signals in a desired image format according to the spatial relationship in which the echo signals are received. For example, the scan converter 230 can arrange the echo signals in a two-dimensional sector format, or a three-dimensional (3D) format of a cone or other shape. In another example of this disclosure, the scan converter 230 can arrange the echo signals as a side-by-side contrast-enhanced image and a tissue image.

[0031] The multiplane reformer 232 is capable of converting echoes received from points in a common plane within a volumetric region of the body into an ultrasound image (e.g., a B-mode image) of that plane, as described, for example, in U.S. Patent US6,443,896 (Detmer). In some examples, the scan converter 230 and the multiplane reformer 232 may be implemented as one or more processors.

[0032] Volume renderer 234 can generate an image (also known as a projection, drawing, or rendering) of a 3D dataset viewed from a given reference point, for example, as described in U.S. Patent US6530885 (Entrekin et al.). In some examples, volume renderer 234 can be implemented as one or more processors. Volume renderer 234 can generate the rendering using any known or future known techniques such as surface rendering and maximum intensity rendering, such as positive or negative rendering.

[0033] In some examples, the system may include a Doppler signal path 262 that couples the output from signal processor 226 to Doppler processor 260. Doppler processor 260 may be configured to estimate the Doppler frequency shift and generate Doppler image data. The Doppler image data may include color data, which is then overlaid with B-mode (i.e., grayscale) image data for display. Doppler processor 260 may be configured to, for example, use a wall filter to filter out unwanted signals (i.e., noise or clutter associated with non-moving tissue). Doppler processor 260 may also be configured to estimate velocity and power using known techniques. For example, the Doppler processor may include a Doppler estimator such as an autocorrelation function, where the velocity (Doppler frequency) estimate is based on the parameters of a hysteresis-autocorrelation function and the Doppler power estimate is based on the amplitude of a hysteresis-zero autocorrelation function. Motion may also be estimated using known phase-domain (e.g., parametric frequency estimators, such as MUSIC, ESPRIT, etc.) or time-domain (e.g., cross-correlation) signal processing techniques. Other estimators related to the temporal or spatial distribution of velocity, such as estimators of acceleration or temporal and / or spatial velocity derivatives, can be used instead of the velocity estimator or as an adjunct to it. In some examples, velocity and power estimates may undergo further thresholding to further reduce noise, as well as segmentation and post-processing, such as padding and smoothing. The velocity and power estimates can then be mapped to a desired range of display colors based on the color map. The color data, also known as Doppler image data, can then be coupled to a scan converter 230, whereby the Doppler image data can be converted to the desired image format and overlaid on a B-mode image of the tissue structure to form a color Doppler or power Doppler image. For example, Doppler image data can be overlaid on a B-mode image of the tissue structure.

[0034] The output from the scan converter 230, the multiplane reformer 232 and / or the volume plotter 334 (e.g., B-mode image, Doppler image) can be coupled to the image processor 236 for further enhancement, buffering and temporary storage before being displayed on the image display 238.

[0035] According to the principles of this disclosure, the image processor 236 can be based on a two-dimensional (2D) color map (e.g., color map 100A and / or color map 100B). These values ​​can be provided by the image processor 236 to the display 238. These values ​​can define the brightness and / or hue of a pixel appearing on the display 238. The 2D color map can define the relationship between the intensity of an ultrasound signal at a location corresponding to a pixel and the brightness and / or hue of a pixel at a given time point. The brightness and / or hue corresponding to the ultrasound signal intensity can vary over time (e.g., images acquired across a sequence at different time points).

[0036] In some embodiments, a 2D color map may be generated by an image processor 236. In some embodiments, how hue and / or brightness change with intensity over time may be predefined. For example, the rate of change of brightness and / or hue at a given intensity level may be predefined. In some embodiments, the rate of change may be based at least in part on the type of organ being imaged (e.g., liver, thyroid), the type of contrast agent used, image acquisition settings (e.g., gain, emission frequency), and / or the type of parameter being studied (e.g., arrival time, clearing).

[0037] In other embodiments, the rate of change can be dynamic. In some embodiments, how brightness and / or hue change with intensity over time, such as the rate of change, can be based on image analysis in real-time or post-processing. For example, image processor 236 can analyze an image to determine the intensity of the ultrasound signal for all pixels in the image and can adjust the intensity ratio of the color map for each image in the sequence such that no more than a threshold number of pixels are at the peak of brightness and / or hue in the image. In some examples, the threshold can be a percentage (e.g., 0.1%, 1%, 5%). In another example, such as parametric imaging, the rate of change of brightness and / or hue for a given intensity can be based on parameters calculated by the image processor. For example, images in the sequence can be analyzed to determine the time to peak, arrival time, elution rate, and / or other desired parameters of the contrast agent (e.g., concentration, flow rate, perfusion rate). Based on the calculated parameters, a 2D color map can be determined and then brightness and / or hue values ​​for the pixels can be assigned.

[0038] Although pixels are referenced, it should be understood that the principles of this disclosure can also be applied to voxels in three-dimensional images.

[0039] In some embodiments, the user may determine, for example via user interface 224, whether the 2D color map corresponds to luminance corresponding to intensity changing over time, hue corresponding to intensity changing over time, or a combination thereof. In some embodiments, whether the change of the 2D color map over time is predetermined or dynamic may be determined by the user through user interface 224.

[0040] The graphics processor 240 can generate graphic overlays for display alongside images. These overlays may include standard identification information such as the patient's name, date and time, imaging parameters, etc., of the images. For these purposes, the graphics processor can be configured to receive input from the user interface 224, such as typed patient names or other annotations. The user interface 224 may also be coupled to a multiplane reformer 232 for selecting and controlling the display of multiple multiplane reformulated (MPR) images.

[0041] System 200 may include local memory 242. Local memory 242 may be implemented as any suitable non-transitory computer-readable medium (e.g., flash drive, disk drive). Local memory 242 may store data generated by system 200, including B-mode images, masks, executable instructions, input provided by the user through user interface 224, or any other information required for the operation of system 200.

[0042] As previously described, system 200 includes a user interface 224. User interface 224 may include a display 238 and a control panel 252. Display 238 may include a display device implemented using various known display technologies such as LCD, LED, OLED, or plasma display technologies. In some examples, display 238 may include multiple displays. Control panel 252 may be configured to receive user input (e.g., checking type, color map format). Control panel 252 may include one or more hardware controls (e.g., buttons, knobs, dials, encoders, mice, trackballs, or others). In some examples, control panel 252 may additionally or alternatively include software controls (e.g., GUI control elements, or simply GUI controls) provided on a touch-sensitive display. In some examples, display 238 may be a touch-sensitive display that includes one or more software controls of control panel 252.

[0043] In some examples, Figure 2 The various components shown can be combined. For example, image processor 236 and graphics processor 240 can be implemented as a single processor. In another example, scan converter 230 and multi-plane reformer 232 can be implemented as a single processor. In some examples, Figure 2 The various components shown can be implemented as individual components. For example, signal processor 226 can be implemented as a separate signal processor for each imaging mode (e.g., B-mode, Doppler). In some examples, Figure 2 One or more of the various processors shown are implemented by general-purpose processors and / or microprocessors configured to perform specified tasks. In some examples, one or more of the various processors may be implemented as dedicated circuitry. In some examples, one or more of the various processors (e.g., image processor 236) may be implemented using one or more graphics processing units (GPUs).

[0044] Figure 3 This is a block diagram illustrating an example processor 300 according to the principles of this disclosure. Processor 300 can be used to implement one or more processors described herein, for example... Figure 2The image processor 236 is shown. The processor 300 can be any suitable processor type, including but not limited to microprocessors, microcontrollers, digital signal processors (DSPs), field-programmable arrays (FPGAs) where the FPGA has been programmed to form a processor, graphics processing units (GPUs), application-specific circuits (ASICs) where the ASIC is designed to form a processor, or combinations thereof.

[0045] Processor 300 may include one or more cores 302. Core 302 may include one or more arithmetic logic units (ALUs) 804. In some examples, in addition to or in place of ALU 04, core 302 may include a floating-point logic unit (FPLU) 306 and / or a digital signal processing unit (DPU) 308.

[0046] Processor 300 may include one or more registers 312 communicatively coupled to core 302. Registers 312 may be implemented using dedicated logic gates (e.g., flip-flops) and / or any memory technology. In some examples, registers 312 may be implemented using static memory. Registers may provide data, instructions, and addresses to core 302.

[0047] In some examples, processor 300 may include one or more levels of cache memory 310 communicatively coupled to core 302. Cache memory 310 may provide computer-readable instructions to core 302 for execution. Cache memory 310 may provide data for core 302 to process. In some examples, computer-readable instructions may already be provided to cache memory 310 by local memory (e.g., local memory attached to external bus 316). Cache memory 310 may be implemented using any suitable cache memory type, such as metal-oxide-semiconductor (MOS) memory, such as static random access memory (SRAM), dynamic random access memory (DRAM), and / or any other suitable memory technology.

[0048] Processor 300 may include controller 314, which can control inputs from other processors and / or components included in the system (e.g., control panel 252 and scan converter 230 shown in FIG. 1) to processor 300 and / or outputs from processor 300 to other processors and / or components included in the system (e.g., display 238 and volume plotter 234 shown in FIG. 1). Controller 314 can control data paths in ALU 304, FPLU 306, and / or DSPU 308. Controller 314 may be implemented as one or more state machines, data paths, and / or dedicated control logic. The gates of controller 314 may be implemented as stand-alone gates, FPGAs, ASICs, or any other suitable technology.

[0049] Register 312 and cache 310 can communicate with controller 314 and core 302 via internal connections 320A, 320B, 320C and 320D. These internal connections can be implemented as buses, multiplexers, cross switches and / or any other suitable connection technology.

[0050] The processor 300's inputs and outputs can be provided via a bus 316, which may include one or more wires. The bus 316 may be communicatively coupled to one or more components of the processor 300, such as the controller 314, cache 310, and / or register 312. The bus 316 may also be coupled to one or more components of the system, such as the previously mentioned display 238 and control panel 252.

[0051] Bus 316 may be coupled to one or more external memories. The external memory may include read-only memory (ROM) 332. ROM 332 may be a mask ROM, electrically programmable read-only memory (EPROM), or any other suitable technology. The external memory may include random access memory (RAM) 333. RAM 333 may be static RAM, battery-backed static RAM, dynamic RAM (DRAM), or any other suitable technology. The external memory may include electrically erasable programmable read-only memory (EEPROM) 335. The external memory may include flash memory 334. The external memory may include a magnetic storage device, such as a disk 336. In some examples, the external memory may be included in the system, for example... Figure 2 The ultrasound imaging system 200 shown includes, for example, local memory 242.

[0052] Figure 4A This is an example contrast-enhanced ultrasound (CEUS) image 400A of the liver generated using a 1D color map 410. Figure 4B Example CEUS image 400B of the liver generated using a two-dimensional color map 412 according to an embodiment of this disclosure. Both images were generated from ultrasound signals acquired at the same time point (e.g., the same images in a sequence of images acquired over time). In both images 400A and 400B, lesions 402 and large branching vessels 404 are visible due to the presence of contrast agent. However, in image 400A, sufficient contrast agent has accumulated in the liver tissue, causing the image to begin to saturate and blurring the smaller vascular systems. For example, as shown by circles 406 and 408, smaller vessels obscured by saturation in image 400A are visible in image 400B because the intensity scale of the image changes over time, which in some examples may penalize pixels arriving later.

[0053] Figure 5AAn exemplary CEUS image 500A of the thyroid gland is generated using a 1D color image 510. Figure 5B This is an example CEUS image 500B of a thyroid gland generated using a two-dimensional color map 512 according to an embodiment of this disclosure. Both images are generated from ultrasound signals acquired at the same time point (e.g., the same images in a sequence of images acquired over time). In both images, lesions can be seen in the area within circle 502, and nodules can be seen below the area indicated by circle 504. Although contrast agent is present in the vascular system of the lesion and within the nodules, in image 500A, it is not clear which areas of the lesion and nodules receive and / or accumulate contrast agent before other areas. However, in image 500B, based on calculated arrival times, areas of lesions and nodules that receive and / or accumulate contrast agent at earlier time points are shown in pink, while areas that receive and / or accumulate contrast agent at later time points are shown in blue-green. Furthermore, the brightness of each hue represents the intensity of the ultrasound signal. Therefore, arrival time and intensity information can be viewed simultaneously.

[0054] Figure 6A This is an example CEUS image 600A of the liver generated using 1D color map 610. Figure 6B Example CEUS image 600B of the liver generated using a two-dimensional color map according to embodiments of this disclosure. Both images are generated from ultrasound signals acquired at the same time point (e.g., the same images in a sequence of images acquired over time). In both images, a lesion 602 with a necrotic core 604 can be seen. Although contrast agent is present in the vascular system of lesion 602, in image 600A, it is unclear which areas of lesion 602 and surrounding liver tissue received and / or accumulated contrast agent before other areas. However, in image 600B, based on calculated arrival times, areas of lesion 620 and tissue that received and / or accumulated contrast agent at earlier time points are shown in pink, while areas that received and / or accumulated contrast agent at later time points are shown in blue-green. Furthermore, the brightness of each hue represents the ultrasound signal intensity. Thus, arrival time and intensity information can be viewed simultaneously. Although blue-green and pink are used in the examples herein, it should be understood that other hues and / or additional hues (e.g., green, yellow, red, blue) can be used.

[0055] Figure 4B An example of how to use 2D color maps for visualization of CEUS imaging is shown. Figure 5B and 6B An example is shown of how to use 2D color maps to simultaneously visualize multiple parameters for parametric CEUS imaging. Although in Figure 5B and Figure 6BThe example shown illustrates arrival time, but multiple parameters in a 2D color map can include arrival time, flight time, microbubble concentration, flow rate, and / or perfusion rate.

[0056] After acquiring the ultrasound signal, a 2D color mapping is performed on the ultrasound signal to intensity-based brightness and / or hue. That is, the 2D color mapping affects the display of the ultrasound image generated from the ultrasound signal, but it does not affect the acquisition of the ultrasound image. Therefore, the underlying data provided by the ultrasound signal is not altered by the 2D color mapping. Thus, while 2D color mapping can be used to improve the visualization of CEUS image data, the "original" CEUS image data can be preserved. This can be advantageous for users of post-processing software that performs quantitative analysis on CEUS image data, as the software may require some or all parameters of the CEUS scan to remain constant over time.

[0057] Figure 7 This is a flowchart of method 700 according to an embodiment of the present disclosure. In some embodiments, some or all of the steps of method 700 may be performed by... Figure 2 The imaging system 200 shown is in operation.

[0058] At box 702, the step of "receiving a sequence of ultrasound images" can be performed. In some embodiments, each image in the sequence of ultrasound images can be acquired at different time points. In some embodiments, the sequence of ultrasound images can be received by an image processor, such as image processor 236. At box 704, the step of "applying a time-varying color map" can be performed. In some embodiments, a time-varying color map can be applied to each ultrasound image in the sequence. The time-varying color map can include a two-dimensional (2D) color map that associates a given intensity of an ultrasound signal with brightness and / or hue values ​​that change over time. In some embodiments, applying the time-varying color map can include assigning different values ​​of brightness and / or hue values ​​to pixels representing ultrasound signals of the same intensity acquired at different time points for each image in the sequence. In some embodiments, the application can be performed by an image processor. At box 706, the step of "displaying a sequence of ultrasound images" can be performed. In some embodiments, the display can be performed by a display such as display 238.

[0059] Optionally, in some embodiments, method 700 may further include block 708, in which the step of "receiving user input" may be performed. In some embodiments, the user input may be received via a user interface, such as user interface 224. In some embodiments, the user input may be used to generate a 2D color map. In some embodiments, block 708 may be performed before or after block 702. In some embodiments, block 708 may be performed concurrently with block 702.

[0060] Optionally, in some embodiments, method 700 may include administering a contrast agent to the object prior to execution block 702. In some embodiments, the contrast agent may comprise microbubbles. In some embodiments, the contrast agent may be administered by injection, such as injection into a blood vessel. In some embodiments, method 700 may include acquiring ultrasound signals from the object, for example, using an ultrasound probe such as ultrasound probe 212. In some embodiments, method 700 may include a sequence for generating ultrasound images from the ultrasound signals. This sequence may be generated at least in part by a signal processor, a B-mode processor, a Doppler processor, a scan converter, and / or an image processor.

[0061] In some embodiments, method 700 may further include block 710, in which the step of "generating a 2D color map" may be performed. In some embodiments, the 2D color may be generated by an image processor. Generating a 2D color map may include: determining the intensity of the ultrasound signal for all pixels of each image in the ultrasound image sequence, and adjusting the intensity scale of the 2D color map for each image in the ultrasound image sequence such that the number of pixels in each image of the ultrasound image sequence that are equal to a peak for at least one of luminance or hue is equal to or less than a threshold. In some embodiments, block 710 may be performed before blocks 702 and / or 708. In some embodiments, block 710 may be performed simultaneously with blocks 702 and / or 708. In some embodiments, block 710 may be performed after blocks 702 and / or 708.

[0062] In some embodiments, generating a 2D colorimetric image may include analyzing all images in an ultrasound image sequence to determine parameters and adjusting the intensity scale of the 2D colorimetric image of each image in the ultrasound image sequence based at least in part on these parameters. In some embodiments, the parameters may be parameters of the contrast agent. In some embodiments, the parameters may include at least one of time to peak, arrival time, elution rate, concentration, flow rate, or perfusion rate.

[0063] As described herein, time-varying 2D color maps can be used to visualize image sequences. In some examples, a single hue can be used, where the brightness value corresponding to a hue of different intensities varies over time. In some examples, the hue used for the intensity scale may change over time. In still other examples, both hue and brightness can change over time relative to intensity. In some applications, 2D color maps according to the principles of this disclosure can allow for better visualization of image sequences (e.g., CEUS imaging) and / or allow for the simultaneous visualization of multiple parameters in parametric imaging.

[0064] In various examples of implementing components, systems, and / or methods using programmable devices such as computer-based systems or programmable logic, it should be understood that the aforementioned systems and methods can be implemented using any of the known or later-developed programming languages, such as "C", "C++", "FORTRAN", "Pascal", etc. Therefore, various storage media, such as magnetic computer disks, optical disks, electronic storage devices, etc., can be prepared, which can contain information that can instruct devices, such as computers, to implement the aforementioned systems and / or methods. Once a suitable device can access the information and programs contained on the storage medium, the storage medium can provide the information and programs to that device, thereby enabling that device to perform the functions of the systems and / or methods described herein. For example, if a computer disk containing appropriate materials (e.g., source files, object files, executable files, etc.) is provided to a computer, the computer can receive the information, appropriately configure itself, and perform the functions of the various systems and methods depicted in the above diagrams and flowcharts to achieve various functions. That is, a computer can receive various parts of information relating to different elements of the aforementioned systems and / or methods from the disk, implement individual systems and / or methods, and coordinate the functions of the individual systems and / or methods described above.

[0065] In view of this disclosure, it should be noted that the various methods and apparatuses described herein can be implemented in hardware, software, and firmware. Furthermore, the various methods and parameters are included by way of example only and are not intended to be limiting. In view of this disclosure, those skilled in the art can implement the teachings of this invention while still remaining within the scope of this disclosure, provided they determine their own techniques and the desired apparatus for influencing these techniques. The functionality of one or more processors described herein can be incorporated into a smaller number or a single processing unit (e.g., a CPU) and can be implemented using application-specific integrated circuits (ASICs) or general-purpose processing circuitry programmed to perform the functions described herein in response to executable instructions.

[0066] Although this system may have been described with particular reference to ultrasound imaging systems, it is also contemplated that this system can be extended to other medical imaging systems that acquire one or more images in a systematic manner. Therefore, this system can be used to acquire and / or record image information relating to the kidneys, testes, breasts, ovaries, uterus, thyroid gland, liver, lungs, musculoskeletal system, spleen, heart, arteries, and vascular system, as well as other imaging applications related to ultrasound-guided interventions, but not limited thereto. Furthermore, this system may include one or more procedures that can be used with conventional imaging systems, enabling them to provide the features and advantages of this system. Certain other advantages and features of this disclosure may be apparent to those skilled in the art upon study of this disclosure, or may be experienced by those who employ the novel systems and methods of this disclosure. Another advantage of this system and method is the ease with which conventional medical imaging systems can be upgraded to incorporate the features and advantages of this system, device, and method.

[0067] Of course, it should be understood that any of the examples, paradigms or processes described herein may be combined with one or more other examples, paradigms and / or processes, or may be separate and / or executed in a discrete device or part of a device, depending on the system, device and method described herein.

[0068] Ultimately, the above discussion is intended merely to illustrate the system and method of the invention and should not be construed as limiting the appended claims to any particular paradigm or group of paradigms. Therefore, while the system has been described in detail with reference to exemplary examples, it should be appreciated that numerous variations and alternative examples can be devised by those skilled in the art without departing from the broader spirit and scope of the system and method as set forth in the claims. Consequently, the specification and drawings should be considered illustrative and not intended to limit the scope of the appended claims.

Claims

1. An ultrasound imaging system (200), comprising: An ultrasound probe (212) is configured to receive ultrasound signals to generate a sequence of ultrasound images; as well as Processor (300), which is configured as follows: Time-varying color maps (100A, 100B) are applied to represent the intensity of the ultrasound signal in the sequence, wherein the time-varying color map comprises a two-dimensional (2D) color map that associates a given intensity of the ultrasound signal with at least one of a luminance value or a hue value that varies over time. Individual ultrasound images are generated by assigning different brightness or hue values ​​to pixels representing ultrasound signals of the same intensity acquired at different time points, based on the time-varying color map; and The sequence displays individual ultrasound images.

2. The ultrasound imaging system according to claim 1, wherein, The time-varying color map is generated before acquiring any of the ultrasound signals, and wherein at least one of the brightness values ​​or the hue values ​​varies over time based at least in part on at least one of the following: the type of organ being imaged, the type of contrast agent used, the image acquisition settings, or the type of parameter to be studied.

3. The ultrasound imaging system according to claim 1, wherein, The processor is also configured to generate the time-varying color map after acquiring at least some of the ultrasound signals.

4. The ultrasound imaging system according to claim 3, wherein, The brightness value or the hue value, at least one of which is at least partially based on the analysis of at least some of the ultrasound signals, varies over time.

5. The ultrasound imaging system according to claim 4, wherein, The at least some of the ultrasound signals correspond to at least one image in the sequence, and the analysis includes determining the intensity of the ultrasound signal for all pixels of the at least one image in the sequence, and adjusting the intensity scale of the 2D color map for the at least one image in the sequence such that the number of pixels in the at least one image in the sequence that are equal to the peak value for at least one of the brightness or hue is equal to or less than a threshold.

6. The ultrasound imaging system according to claim 4, wherein, The analysis includes analyzing all ultrasound signals to determine parameters and, at least in part, adjusting the intensity scale of the 2D color map for each image in the sequence based on those parameters.

7. The ultrasound imaging system according to claim 6, wherein, The parameters include at least one of the following: peak time of contrast agent, arrival time, washout rate, concentration, flow rate, or perfusion rate.

8. The ultrasound imaging system according to claim 4, wherein, The analysis is performed in real time.

9. The ultrasound imaging system of claim 1, further comprising a user interface configured to receive user input, wherein, How the intensity corresponding to at least one of the brightness or the hue changes over time is at least in part based on the user input.

10. An ultrasound imaging method (700), comprising: Receive a sequence of ultrasound images (702), wherein each image in the sequence of ultrasound images is acquired at a different time point; A time-varying color map is applied to individual acoustic images in the sequence (704), wherein the time-varying color map comprises a two-dimensional (2D) color map that associates a given intensity of an ultrasound signal with at least one of a brightness value or a hue value that varies over time, and wherein applying the time-varying color map comprises: assigning, for individual images in the sequence, different terms of at least one of the brightness values ​​or the hue values ​​to pixels representing ultrasound signals of the same intensity acquired at different time points; and The sequence (706) displays individual ultrasound images.

11. The method of claim 10, further comprising generating the 2D color map, wherein, Generating the 2D color map includes: Determine the ultrasound signal intensity of all pixels for each image in the sequence of ultrasound images; and The intensity scale of the 2D color map for each image in the sequence of ultrasound images is adjusted such that the number of pixels in each image of the sequence of ultrasound images that have a peak value equal to at least one of the luminance or hue values ​​is equal to or less than a threshold.

12. The method of claim 10, further comprising generating the 2D color map, wherein, Generating the 2D color map includes: Analyze all images in the sequence of ultrasound images to determine parameters; and The intensity scale of the 2D colorimetric image is adjusted for each image in the sequence of ultrasound images based at least in part on the parameters, including at least one of arrival time, time to peak, washout rate, concentration, flow rate, or perfusion rate.

13. The method of claim 10, further comprising receiving user input, wherein, The user input is used to apply the 2D color map.

14. The method of claim 10, further comprising: Apply contrast agent to the subject; Acquire the ultrasonic signal from the object; and The sequence of ultrasound images is generated based on the ultrasound signals.

15. A computer program product comprising computer program code, said computer program code being adapted, when run on a computer, to perform the method according to any one of claims 10 to 13.

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