Generally, the aspects of the technology described herein relate to collection of ultrasound images.
Ultrasound probes may be used to perform diagnostic imaging and/or treatment, using sound waves with frequencies that are higher than those audible to humans. Ultrasound imaging may be used to see internal soft tissue body structures. When pulses of ultrasound are transmitted into tissue, sound waves of different amplitudes may be reflected back towards the probe at different tissue interfaces. These reflected sound waves may then be recorded and displayed as an image to the operator. The strength (amplitude) of the sound signal and the time it takes for the wave to travel through the body may provide information used to produce the ultrasound image. Many different types of images can be formed using ultrasound devices. For example, images can be generated that show two-dimensional cross-sections of tissue, blood flow, motion of tissue over time, the location of blood, the presence of specific molecules, the stiffness of tissue, or the anatomy of a three-dimensional region.
According to one aspect, an apparatus includes processing circuitry configured to receive an ultrasound image, determine a location of a specific point on an anatomical structure depicted in the ultrasound image, and display an indicator of the location of the specific point on the anatomical structure on the ultrasound image.
In some embodiments, the anatomical structure comprises a bladder. In some embodiments, the processing circuitry is configured, when determining the location of the specific point on the anatomical structure depicted in the ultrasound image, to use a statistical model. In some embodiments, the specific point on the anatomical structure has predetermined mathematical characteristics. In some embodiments, the processing circuitry is configured, when automatically determining the location of the specific point on the anatomical structure depicted in the ultrasound image, to use a mathematical formula or algorithm. In some embodiments, the processing circuitry is configured, when determining the location of the specific point on the anatomical structure depicted in the ultrasound image, to determine a centroid of the anatomical structure depicted in the ultrasound image. In some embodiments, the processing circuitry is configured, when determining the location of the specific point on the anatomical structure depicted in the ultrasound image to determine a point on the anatomical structure that is farthest from all the edge points of the anatomical structure.
In some embodiments, the processing circuitry is configured, when displaying the indicator of the location of the specific point on the anatomical structure on the ultrasound image, to display a symbol located at the specific point on the anatomical structure on the ultrasound image. In some embodiments, the processing circuitry is configured, when displaying the indicator of the location of the specific point on the anatomical structure on the ultrasound image, to display a vertical line extending from one edge of the anatomical structure, through the specific point on the anatomical structure, and to the other edge of the anatomical structure. In some embodiments, the processing circuitry is configured, when displaying the indicator of the location of the specific point on the anatomical structure on the ultrasound, to display a horizontal line extending from one edge of the anatomical structure, through the specific point on the anatomical structure, and to the other edge of the anatomical structure.
In some embodiments, the processing circuitry is further configured to display a second indicator when the indicator is within a threshold distance of either or both of a vertical line positioned halfway across a horizontal dimension of the ultrasound image and a horizontal line positioned halfway across a vertical dimension of the ultrasound image. In some embodiments, the processing circuitry is further configured to display a second indicator indicating indicate how close the indicator is to either or both of a vertical line positioned halfway across a horizontal dimension of the ultrasound image and a horizontal line positioned halfway across a vertical dimension of the ultrasound image. In some embodiments, the processing circuitry is further configured to display no other indicators of locations on the anatomical structure.
Some aspects include at least one non-transitory computer-readable storage medium storing processor-executable instructions that, when executed by at least one processor, cause the at least one processor to perform the above aspects and embodiments. Some aspects include a method to perform the actions that the processing device is configured to perform.
Various aspects and embodiments will be described with reference to the following exemplary and non-limiting figures. It should be appreciated that the figures are not necessarily drawn to scale. Items appearing in multiple figures are indicated by the same or a similar reference number in all the figures in which they appear.
Some applications of ultrasound imaging include capturing one or more ultrasound images of an anatomical structure (e.g., a bladder) and performing a clinical calculation based on the one or more ultrasound images. For example, after capturing one or more ultrasound images of a bladder, the volume of the bladder may be calculated. In some applications, it may be helpful to position an ultrasound device capturing an ultrasound image such that the anatomical structure is centered with respect to the horizontal and/or vertical dimensions of the ultrasound image. This may help improve the accuracy of calculations performed based on the anatomical structure in the ultrasound image, as image quality may be better in the center of an ultrasound image. Additionally, centering the anatomical structure may help to minimize the chance that a portion of the anatomical structure will be clipped at the edge of the ultrasound image.
In some embodiments, a processing device displaying ultrasound images collected by an ultrasound device may display a vertical line positioned halfway across the horizontal dimension of the ultrasound image and/or a horizontal line positioned halfway across the vertical dimension of the ultrasound image. The inventors have recognized that it may also be helpful for the processing device to display an indicator of a specific point on an anatomical structure in an ultrasound image. For example, the specific point may be the centroid of the anatomical structure in an ultrasound image. As another example, the specific point may be the point on the anatomical structure that is farthest from all the edge points of the anatomical structure. It should be appreciated that other points on the anatomical structure may be used as well. Examples of indicators include a symbol positioned at the specific portion on the anatomical structure and/or a line extending horizontally or vertically from one edge of the anatomical structure, through the specific point on the anatomical structure, and to the other edge of the anatomical structure. In some embodiments, the processing device may use a statistical model to determine the location of the specific point on the anatomical structure in an ultrasound image. As the ultrasound device collects more ultrasound images that are displayed the processing device, and the anatomical structure is located at different locations on the ultrasound image, the processing device may reposition the indicator such that the indicator continues to be located at the specific point on the anatomical structure.
Displaying the indicator may help the user to position the ultrasound device such that the anatomical structure is centered in the ultrasound image. As the user moves the ultrasound device, the position of the anatomical structure in the ultrasound image may change. When the anatomical structure is positioned in the ultrasound image such that the indicator is positioned within a threshold distance of the vertical line positioned halfway across the horizontal dimension of the ultrasound image and/or within a threshold distance of the horizontal line positioned halfway across the vertical dimension of the ultrasound image, this may indicate that the anatomical structure is centered with respect to the horizontal and/or vertical dimension of the ultrasound image.
It should be appreciated that the embodiments described herein may be implemented in any of numerous ways. Examples of specific implementations are provided below for illustrative purposes only. It should be appreciated that these embodiments and the features/capabilities provided may be used individually, all together, or in any combination of two or more, as aspects of the technology described herein are not limited in this respect.
In act 102, the processing device receives an ultrasound image. The ultrasound image may be generated based on raw ultrasound data collected by the ultrasound device. In some embodiments, the ultrasound device may generate the ultrasound image based on the raw ultrasound data, and at act 102, the processing device may receive the ultrasound image from the ultrasound device. In some embodiments, the ultrasound device may generate scan lines from the raw ultrasound data, and at act 102, the processing device may receive the scan lines from the ultrasound device and generate the ultrasound image based on the scan lines. In some embodiments, at act 102, the processing device may receive the raw ultrasound data from the ultrasound device and generate the ultrasound image based on the raw ultrasound data. The ultrasound image may be the most recently collected ultrasound image by the ultrasound device, and the processing device may receive the ultrasound image in real-time, as it is collected. The process 100 proceeds from act 102 to act 104.
In act 104, the processing device automatically determines a location of a specific point on an anatomical structure depicted in the ultrasound image. For example, the anatomical structure may be the bladder. In some embodiments, the specific point may have predetermined mathematical characteristics. In some embodiments, determining the specific point may include using a mathematical formula or algorithm. Examples of the specific point include the centroid of the anatomical structure and the point on the anatomical structure that is farthest from all the edge points of the anatomical structure, although other specific points may be used. In some embodiments, a statistical model may be trained to automatically determine the location of a specific point on an anatomical structure depicted in an ultrasound image. The statistical model may be stored on the processing device or stored on another electronic device (e.g., a server) and accessed by the processing device.
For the example where the specific point is the centroid of the anatomical structure, in some embodiments, the statistical model may be trained on multiple pairs of input and output training data sets as a segmentation model. Each set of input training data may be an ultrasound image depicting an anatomical structure. Each set of output training data may be a segmentation mask that is an array of values equal in size to the input training data ultrasound image, and pixels corresponding to locations within the anatomical structure in the ultrasound image are manually set to 1 and other pixels are set to 0. Based on this training data, the statistical model may learn to output, based on an inputted ultrasound image, a segmentation mask where each pixel has a value representing the probability that the pixel corresponds to a location within the anatomical structure in the ultrasound image (values closer to 1) or outside the anatomical structure (values closer to 0). The processing device may select all pixels in the segmentation mask that have a value greater than a threshold value (e.g., 0.5) as being within the anatomical structure. To determine the location of the centroid of the anatomical structure depicted in the ultrasound image, the processing device may calculate the arithmetic mean of all the locations of pixels that were determined to be within the anatomical structure. For example, the processing device may calculate the arithmetic mean of the horizontal locations of all pixels within the anatomical structure and the arithmetic mean of the vertical locations of all pixels within the anatomical structure. The processing device may determine the location of the centroid of the anatomical structure to be the pixel having a horizontal position that is at the arithmetic mean of all pixels within the anatomical structure and having a vertical position that is at the arithmetic mean of all pixels within the anatomical structure.
In some embodiments, the statistical model may be trained on multiple pairs of input and output training data sets as a keypoint localization model. Each set of input training data may be an ultrasound image depicting an anatomical structure. Each set of output training data may be an array of values that is the same size as the input training data ultrasound image, where the pixel corresponding to the centroid of the anatomical structure in the ultrasound image is manually set to a value of 1 and every other pixel has a value of 0. Based on this training data, the statistical model may learn to output, based on an inputted ultrasound image, an array of values that is the same size as the inputted image, where each pixel in the array consists of a probability that that pixel is where the centroid of an anatomical structure depicted in the ultrasound image is located. The processing device may select the pixel having the highest probability as the location of the specific point on the anatomical structure in the ultrasound image.
In some embodiments, the statistical model may be trained on multiple pairs of input and output training data sets to use regression. Each set of input training data may be an ultrasound image depicting an anatomical structure. Each set of output training data set may be the pixel location of the centroid of the anatomical structure in the input training data ultrasound image. Based on this training data, the statistical model may learn to output, based on an inputted ultrasound image, the horizontal and vertical pixel coordinates of the centroid of an anatomical structure depicted in the ultrasound device.
For the example where the specific point is the point on the anatomical structure that is farthest from all the edge points of the anatomical structure, in some embodiments, the statistical model may be trained on multiple pairs of input and output training data sets as a segmentation model. Each set of input training data may be an ultrasound image depicting an anatomical structure. Each set of output training data may be a segmentation mask that is an array of values equal in size to the input training data ultrasound image, and pixels corresponding to locations on the boundary of the anatomical structure in the ultrasound image are manually set to 1 and other pixels are set to 0. Based on this training data, the statistical model may learn to output, based on an inputted ultrasound image, a segmentation mask where each pixel has a value representing the probability that the pixel corresponds to a boundary of the anatomical structure in the ultrasound image (values closer to 1) or does not correspond to a boundary of the anatomical structure (values closer to 0). The processing device may select all pixels in the segmentation mask that have a value greater than a threshold value (e.g., 0.5) as being on the boundary of the anatomical structure. To determine the location of the point on the anatomical structure that is farthest from all the edge points of the anatomical structure depicted in the ultrasound image, the processing device may calculate, for every pixel inside the boundary, the sum of the distances of that pixel to every pixel on the boundary. The processing device may then select the pixel having the greater sum of distances as the location of the specific point on the anatomical structure in the ultrasound image.
In some embodiments, the statistical model may be trained on multiple pairs of input and output training data sets as a keypoint localization model. Each set of input training data may be an ultrasound image depicting an anatomical structure. Each set of output training data may be an array of values that is the same size as the input training data ultrasound image, where the pixel corresponding to the point on the anatomical structure that is farthest from all the edge points of the anatomical structure in the ultrasound image is manually set to a value of 1 and every other pixel has a value of 0. Based on this training data, the statistical model may learn to output, based on an inputted ultrasound image, an array of values that is the same size as the inputted image, where each pixel in the array consists of a probability that that pixel is where the point on the anatomical structure that is farthest from all the edge points of the anatomical structure in the ultrasound image is located. The processing device may select the pixel having the highest probability as the location of the specific point on the anatomical structure in the ultrasound image.
In some embodiments, the statistical model may be trained on multiple pairs of input and output training data sets to use regression. Each set of input training data may be an ultrasound image depicting an anatomical structure. Each set of output training data set may be the pixel location of the point on the anatomical structure that is farthest from all the edge points of the anatomical structure. Based on this training data, the statistical model may learn to output, based on an inputted ultrasound image, the horizontal and vertical pixel coordinates of the point on the anatomical structure that is farthest from all the edge points of the anatomical structure. The process 100 proceeds from act 104 to act 106.
In act 106, the processing device displays the ultrasound image (received in act 102) and an indicator of the location of the specific point on the anatomical structure (determined in act 104) superimposed on the ultrasound image. The processing device may display the ultrasound image on a display screen of the processing device. The indicator of the location of the specific point on the anatomical structure may include a symbol (e.g., a box, a rounded box, a circle, an “x”, a crosshairs, etc.) and may be located at the location of the specific point on the anatomical structure. For example, one of the pixels of the symbol may be at the location of the specific point on the anatomical structure in the ultrasound image (or is the pixel closest to this location). The symbol may be centered at the location of the specific point, or the center of the symbol may be at the pixel which is closest to this location. In some embodiments, the indicator of the location of the specific point on the anatomical structure may not be located at the location of the specific point, but at a location that is based on the location of the specific point (e.g., a certain number of pixels away from the specific point in a particular direction). In some embodiments, only one indicator (namely, the indicator of the location of the specific point on the anatomical structure) may be displayed on the anatomical structure, and no other indicators of locations on the anatomical structure may be displayed.
In some embodiments, the indicator may include a vertical line extending from one edge of the anatomical structure, through the specific point on the anatomical structure, to the other edge of the anatomical structure. In some embodiments, the indicator may include a horizontal line extending from one edge of the anatomical structure, through the specific point on the anatomical structure, and to the other edge of the anatomical structure. In some embodiments, the indicator may include two or more of a symbol at the specific point on the anatomical structure, a horizontal line extending through the specific point, and a vertical line extending through the specific point. In some embodiments, to position such vertical lines or horizontal lines, the processing device may use a segmentation mask for the anatomical structure that is returned by a statistical model, where the segmentation mask indicates the boundary of the anatomical structure (as described above). Thus, by using the location of the specific point on the anatomical structure and the boundary of the anatomical structure, the processing device may determine how to position a vertical or horizontal line extending from one edge of the anatomical structure, through the specific point on the anatomical structure, and to the other edge of the anatomical structure.
In
Displaying the symbol 206 may help the user position the ultrasound device such that the anatomical structure 204 is centered in the ultrasound image 202. As the user moves the ultrasound device, the position of the anatomical structure 204 in the ultrasound image 202 may change. Because in
Displaying the vertical line 310 may help the user position the ultrasound device such that the anatomical structure 204 is centered in the ultrasound image 202. As the user moves the ultrasound device, the position of the anatomical structure 204 in the ultrasound image 202 may change. Because in
Displaying the symbol 206 may help the user position the ultrasound device such that the anatomical structure 204 is centered in the ultrasound image 202. As the user moves the ultrasound device, the position of the anatomical structure 204 in the ultrasound image 202 may change. Because in
Displaying the horizontal line 514 may help the user position the ultrasound device such that the anatomical structure 204 is centered in the ultrasound image 202. As the user moves the ultrasound device, the position of the anatomical structure 204 in the ultrasound image 202 may change. Because in
Displaying the symbol 206 may help the user position the ultrasound device such that the anatomical structure 204 is centered in the ultrasound image 202. As the user moves the ultrasound device, the position of the anatomical structure 204 in the ultrasound image 202 may change. Because in
Displaying the vertical line 310 and the horizontal line 514 may help the user position the ultrasound device such that the anatomical structure 204 is centered in the ultrasound image 202. As the user moves the ultrasound device, the position of the anatomical structure 204 in the ultrasound image 202 may change. Because in
It should be appreciated that the processing device may change one or more of the color, the saturation, and the transparency of the segmentation mask 730D in other GUIs described herein, for example, based on the distance from the symbol 206 vertically to the horizontal line 412, from the symbol 206 diagonally to the intersection of the vertical line 208 and the horizontal line 412, from the vertical line 310 on the anatomical structure 204 horizontally to the vertical line 208, from the horizontal line 514 on the anatomical structure 204 vertically to the horizontal line 412, or from the intersection of the vertical line 310 and the horizontal line 514 to the intersection of the vertical line 208 and the horizontal line 412.
In some embodiments, the processing device may change the color of the symbol 206, the vertical line 310, and/or the horizontal line 514 based on its distance from the horizontal line 412, the vertical line 208, or from the intersection of the vertical line 208 and the horizontal line 412. In some embodiments, the processing device may change the color of the horizontal line 412 and/or the vertical line 208 based on their distance, or the distance of their intersection, from the symbol 206, the vertical line 310, and/or the horizontal line 514. For example, the processing device may change the color from red at far distances to green at near distances.
In some embodiments, a GUI may include both a symbol and either or both of a horizontal line and vertical line extending through the anatomical structure. In some embodiments in which the indicator is a symbol, the symbol may be sized based on how close it is desired for the specific point to be to the vertical line and/or the horizontal line extending through the ultrasound image. For example, the size of the symbol may be such that when the symbol touches the vertical line or horizontal line, the specific point is within the desired distance of the vertical line and/or the horizontal line.
While the above description has used the bladder as an exemplary anatomical structure, the methods and apparatuses described herein may also be applied to collecting ultrasound images of the thyroid, the abdominal aorta, a superficial artery, the brain (e.g., a neonatal brain), the liver, the breast, the kidney, the thyroid, and amniotic fluid. Example applications include venous access identification when imaging a superficial artery; imaging benign hemangiomas in the liver; imaging nodules in the thyroid, imaging cancerous tumors in the liver, breast, kidney, and pancreas to detect changes over time; and amniotic fluid evaluation.
The ultrasound device 1006 includes ultrasound circuitry 1009. The processing device 1007 includes a camera 1015, a display screen 1008, a processor 1010, a memory 1012, and an input device 1018. The processing device 1007 is in wired (e.g., through a lightning connector or a mini-USB connector) and/or wireless communication (e.g., using BLUETOOTH®, ZIGBEE, and/or WiFi wireless protocols) with the ultrasound device 1006. The processing device 1007 is in wireless communication with the one or more servers 1034 over the network 1016. However, the wireless communication with the processing device 1034 is optional.
The ultrasound device 1006 may be configured to generate ultrasound data that may be employed to generate an ultrasound image. The ultrasound device 1006 may be constructed in any of a variety of ways. In some embodiments, the ultrasound device 1006 includes a transmitter that transmits a signal to a transmit beamformer which in turn drives transducer elements within a transducer array to emit pulsed ultrasonic signals into a structure, such as a patient. The pulsed ultrasonic signals may be back-scattered from structures in the body, such as blood cells or muscular tissue, to produce echoes that return to the transducer elements. These echoes may then be converted into electrical signals by the transducer elements and the electrical signals are received by a receiver. The electrical signals representing the received echoes are sent to a receive beamformer that outputs ultrasound data. The ultrasound circuitry 1009 may be configured to generate the ultrasound data. The ultrasound circuitry 1009 may include one or more ultrasonic transducers monolithically integrated onto a single semiconductor die. The ultrasonic transducers may include, for example, one or more capacitive micromachined ultrasonic transducers (CMUTs), one or more CMOS (complementary metal-oxide-semiconductor) ultrasonic transducers (CUTs), one or more piezoelectric micromachined ultrasonic transducers (PMUTs), and/or one or more other suitable ultrasonic transducer cells. In some embodiments, the ultrasonic transducers may be formed the same chip as other electronic components in the ultrasound circuitry 1009 (e.g., transmit circuitry, receive circuitry, control circuitry, power management circuitry, and processing circuitry) to form a monolithic ultrasound device. The ultrasound device 1006 may transmit ultrasound data and/or ultrasound images to the processing device 1007 over a wired (e.g., through a lightning connector or a mini-USB connector) and/or wireless (e.g., using BLUETOOTH®, ZIGBEE, and/or WiFi wireless protocols) communication link.
Referring now to the processing device 1007, the processor 1010 may include specially-programmed and/or special-purpose hardware such as an application-specific integrated circuit (ASIC). For example, the processor 1010 may include one or more graphics processing units (GPUs) and/or one or more tensor processing units (TPUs). TPUs may be ASICs specifically designed for machine learning (e.g., deep learning). The TPUs may be employed to, for example, accelerate the inference phase of a neural network. The processing device 1007 may be configured to process the ultrasound data received from the ultrasound device 1006 to generate ultrasound images for display on the display screen 1008. The processing may be performed by, for example, the processor 1010. The processor 1010 may also be adapted to control the acquisition of ultrasound data with the ultrasound device 1006. The ultrasound data may be processed in real-time during a scanning session as the echo signals are received. In some embodiments, the displayed ultrasound image may be updated a rate of at least 5 Hz, at least 10 Hz, at least 20 Hz, at a rate between 5 and 60 Hz, at a rate of more than 20 Hz. For example, ultrasound data may be acquired even as images are being generated based on previously acquired data and while a live ultrasound image is being displayed. As additional ultrasound data is acquired, additional frames or images generated from more-recently acquired ultrasound data are sequentially displayed. Additionally, or alternatively, the ultrasound data may be stored temporarily in a buffer during a scanning session and processed in less than real-time.
The processing device 1007 may be configured to perform certain of the processes (e.g., the process 100) described herein using the processor 1010 (e.g., one or more computer hardware processors) and one or more articles of manufacture that include non-transitory computer-readable storage media such as the memory 1012. The processor 1010 may control writing data to and reading data from the memory 1012 in any suitable manner. To perform certain of the processes described herein, the processor 1010 may execute one or more processor-executable instructions stored in one or more non-transitory computer-readable storage media (e.g., the memory 1012), which may serve as non-transitory computer-readable storage media storing processor-executable instructions for execution by the processor 1010. The camera 1015 may be configured to detect light (e.g., visible light) to form an image. The camera 1015 may be on the same face of the processing device 1007 as the display screen 1008. The display screen 1008 may be configured to display images and/or videos, and may be, for example, a liquid crystal display (LCD), a plasma display, and/or an organic light emitting diode (OLED) display on the processing device 1007. The input device 1018 may include one or more devices capable of receiving input from a user and transmitting the input to the processor 1010. For example, the input device 1018 may include a keyboard, a mouse, a microphone, touch-enabled sensors on the display screen 1008, and/or a microphone. The display screen 1008, the input device 1018, and the camera 1015 may be communicatively coupled to the processor 1010 and/or under the control of the processor 1010.
It should be appreciated that the processing device 1007 may be implemented in any of a variety of ways. For example, the processing device 1007 may be implemented as a handheld device such as a mobile smartphone or a tablet. Thereby, a user of the ultrasound device 1006 may be able to operate the ultrasound device 1006 with one hand and hold the processing device 1007 with another hand. In other examples, the processing device 1007 may be implemented as a portable device that is not a handheld device, such as a laptop. In yet other examples, the processing device 1007 may be implemented as a stationary device such as a desktop computer. The processing device 1007 may be connected to the network 1016 over a wired connection (e.g., via an Ethernet cable) and/or a wireless connection (e.g., over a WiFi network). The processing device 1007 may thereby communicate with (e.g., transmit data to) the one or more servers 1034 over the network 1016. For further description of ultrasound devices and systems, see U.S. patent application Ser. No. 15/415,434 titled “UNIVERSAL ULTRASOUND DEVICE AND RELATED APPARATUS AND METHODS,” filed on Jan. 25, 2017 and published as U.S. Pat. App. Publication No. 2017-0360397 A1 (and assigned to the assignee of the instant application), which is incorporated herein by reference in its entirety.
Various aspects of the present disclosure may be used alone, in combination, or in a variety of arrangements not specifically described in the embodiments described in the foregoing and is therefore not limited in its application to the details and arrangement of components set forth in the foregoing description or illustrated in the drawings. For example, aspects described in one embodiment may be combined in any manner with aspects described in other embodiments.
Various inventive concepts may be embodied as one or more processes, of which an example has been provided. The acts performed as part of each process may be ordered in any suitable way. Thus, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments. Further, one or more of the processes may be combined and/or omitted, and one or more of the processes may include additional steps.
The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”
The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and/or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified.
As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified.
Use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.
As used herein, reference to a numerical value being between two endpoints should be understood to encompass the situation in which the numerical value can assume either of the endpoints. For example, stating that a characteristic has a value between A and B, or between approximately A and B, should be understood to mean that the indicated range is inclusive of the endpoints A and B unless otherwise noted.
The terms “approximately” and “about” may be used to mean within ±20% of a target value in some embodiments, within ±10% of a target value in some embodiments, within ±5% of a target value in some embodiments, and yet within ±2% of a target value in some embodiments. The terms “approximately” and “about” may include the target value.
Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
Having described above several aspects of at least one embodiment, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be object of this disclosure. Accordingly, the foregoing description and drawings are by way of example only.
The present application is a continuation of U.S. application Ser. No. 18/133,049, filed on Apr. 11, 2023, which is a continuation of U.S. patent application Ser. No. 16/839,020, filed on Apr. 2, 2020, now U.S. Pat. No. 11,631,172, which claims the benefit under 35 U.S.C. § 119 (e) of U.S. Provisional Patent Application Ser. No. 62/828,726, filed Apr. 3, 2019. The entire disclosures of the foregoing applications are incorporated by reference herein.
Number | Date | Country | |
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62828726 | Apr 2019 | US |
Number | Date | Country | |
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Parent | 18133049 | Apr 2023 | US |
Child | 18788705 | US | |
Parent | 16839020 | Apr 2020 | US |
Child | 18133049 | US |