Patent Publication Number: US-2018049711-A1

Title: Method of panoramic imaging with a dual plane fluoroscopy system

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority to, and the benefit of, co-pending U.S. Provisional Application No. 62/377,469, filed Aug. 19, 2016, for all subject matter common to both applications. The disclosure of said provisional application is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an imaging system and method for producing a panoramic image for use during a fluoroscopic procedure. In particular, the present invention relates to fluoroscopic imaging system configured to create a single non-parallax panoramic image in real-time from a plurality of individual images captured by the imaging system while the imaging system is traversing over a patient. 
     BACKGROUND 
     Generally, the usage of conventional C-arm X-ray equipment is well known in the medical art of surgical and other interventional procedures. Traditionally, the utilization of C-arm X-ray equipment enables flexibility in operation procedures and in the positioning process, which is reflected by a number of degrees of freedom of movement provided by the C-arm X-ray equipment. 
     In a conventional implementation, a C-arm gantry is slidably mounted to a support structure to enable orbiting rotational movement of the C-arm about a center of curvature for the C-arm. Additionally, the C-arm equipment provides a lateral rotation motion rotating along the horizontal axis of the support structure. Moreover, the C-arm equipment also can include an up-down motion along the vertical axis, a cross-arm motion along the horizontal axis, and a wig-wag motion along the vertical axis. 
     A traditional C-arm provides real time X-ray images of a patient&#39;s spinal anatomy which is used to guide a surgeon during an operating procedure. For example, spinal deformity correction is a type of surgery that frequently uses the C-arm during an operation procedure. Such surgeries typically involve corrective manoeuvres to improve the sagittal or coronal profile of the patient. However, an intra-operative estimation of the amount of correction is difficult. Mostly, anteroposterior (AP) and lateral fluoroscopic images are used, but are limited as the AP and lateral fluoroscopic images only depict a small portion of the spine in a single C-arm image. The small depiction of the spine in traditional C-arm images is due to the limited field of view of a C-arm machine. As a result, spine surgeons are missing an effective tool to image an entire spine of a patient for use during surgery and assessing the extent of correction in scoliotic deformity. 
     Similarly, the full bone structure of X-ray images cannot be captured in a single scan with existing Digital radiography (DR) systems. Stitching methods and systems for X-ray images is very important for scoliosis or lower limb malformation diagnosing and pre-surgical planning. Although radiographs that are obtained either by using a large field detector or by image stitching can be used to image an entire spine, the radiographs are usually not available for intra-operative interventions because there are not motorized positioning mechanisms available for conventional digital radiography systems along a horizontal positioning of a patient. 
     One alternative to conventional radiographs is to develop methods and systems to stitch multiple intra-operatively acquired small fluoroscopic images together to be able to display the entire spine at once. It has been known that there are a few methods to create a single panoramic image of a long view using C-arm from several individual fluoroscopic X-ray images. Panoramic images are useful preoperatively for diagnosis, and intra-operatively for long bone fragment alignment, for making anatomical measurements, and for documenting surgical outcomes. (See, U.S. Patent Application No. 2011/0188726) U.S. Patent Application No. 2011/0188726 disclosed a method for generating a panoramic image of a region of interest (ROI) which is larger than a field of a view of a radiation based imaging device, including, positioning markers along the ROI, acquiring a set of images along the ROI, wherein the acquired images have at least partially overlapping portions, aligning at least two separate images by aligning a common marker found in both images and compensating for a difference between a distance from a radiation source to the marker element and the distance from the radiation source to a plane of interest. 
     Although the C-arm X-ray equipment is smart and flexible in positioning process, it is often desirable to take X-rays of a patient from both the AP and LAT positions (two perpendicular angles). In such situations, the operators have to reposition the C-arm because C-arm configurations do not allow for such perpendicular bi-planar imaging. For taking the X-rays from different angles at the same time without repositioning the X-ray apparatus, such a configuration is often referred to as bi-planar imaging, also known as G-arm or G-shape arm (see U.S. Pat. No. 8,992,082), that allows an object to be viewed in two planes simultaneously. The two X-ray beams emitted from the two X-ray tubes may cross at an iso-center. 
     A traditional mobile dual plane fluoroscopy device has advantages of each of C-shaped, G-shaped, and ring-shaped arm configurations. The device consists of a gantry that supports X-ray imaging machinery. The gantry is formed to allow two bi-planar X-rays to be taken simultaneously or without movement of the equipment and/or patient. The gantry is adjustable to change angles of the X-ray imaging machinery. In addition, the X-ray receptor portion of the X-ray imaging machinery may be positioned on retractable and extendable arms, allowing the apparatus to have a larger access opening when not in operation, but to still provide bi-planar X-ray ability when in operation. 
     SUMMARY 
     There is a need for improvements to producing a panoramic image of a patient subject, in real-time, during a medical procedure. The present invention is directed toward further solutions to address this need, in addition to having other desirable characteristics. Specifically, the present invention provides a system and method that is configured to capture a plurality of image frames while an imaging device traverses over a patient, transforms the plurality of image frames into a single non-parallax panoramic image, and generates and displays the panoramic image to an operating user in real-time. The present invention is adapted to find the overlapping region of a plurality of images, utilize a correlation coefficient to evaluate similarities of overlapping region(s) of the plurality of images, and perform weighted blending to produce the panorama image in real-time. 
     In accordance with example embodiments of the present invention, a method for panoramic imaging is provided. The method includes activating an imaging system. The system includes a first imaging assembly mounted on a support gantry, the first imaging assembly configured to capture image data comprising a plurality of image frames. The system also includes a control unit that directs movement and positioning of the support gantry and a processing and display device in communication with the first imaging assembly, the processing and display device configured to stitch and display the plurality of image frames as a single panoramic image. The method also includes traversing the support gantry, via the control unit, parallel to a subject to be imaged. The processing and display device constructs and displays the panoramic image in real-time based on the traversing of the support gantry and the plurality of image frames obtained during the traversing. 
     In accordance with aspects of the present invention, the stitching includes calculating a motion between image frames along an X-axis of the traversing the support gantry and determining a size of an original panoramic image based on the calculated motion between image frames. The stitching also includes downsampling the original panoramic image along the X-axis, determining a downsample size of the original panoramic image based on the downsampling, and downsampling the original panoramic image along the Y-axis. The downsampling can also include selecting two or more overlapping lines between adjacent image frames, determining the traversing speed of the support gantry, performing a weighted operation to reduce parallax error, interpolating each of the two or more overlapping lines, and normalizing and summing the interpolated overlapping lines. The weighted operation can be a Gaussian formula of: W i(k) =e −0.5(Dist(k)/64)     2   , where Wi(k) is a Gaussian weight and Dist(k) is a distance between overlapping lines for image frames. The downsampling can be performed without a weighted operation. 
     In accordance with aspects of the present invention, the stitching comprises identifying a correlation of overlapping region(s) from adjacent images to find an inter frame motion. The identification of the correlation of overlapping region(s) can include selecting a search area size for searching for a correlation within each of the plurality of image frames, such that the search area size is smaller than a single image frame size, selecting a pattern image size to be used in the correlation search, such that the pattern image size is smaller than the search area size, comparing a pattern image to an area defined by the search area size for each of the plurality of image frames, and determining a correlation value based on the comparing. 
     In accordance with aspects of the present invention, the first imaging assembly comprises a first imaging energy emitter that is positioned opposite a first imaging receptor, such that one of the first imaging energy emitter or the first imaging receptor is positioned at the first terminal end of the support gantry. The imaging system can further include a second imaging assembly that is positioned on the support gantry and comprising a second imaging energy emitter positioned that is opposite a second imaging receptor, such that one of the second imaging energy emitter or the second imaging receptor is positioned at the second terminal end of the support gantry. 
     In accordance with aspects of the present invention, the tracking wheels configured to enable traversing of the support gantry and tracking a distance traversed by the support gantry. 
     In accordance with example embodiments of the present invention, a system for panoramic imaging is provided. The system includes a support gantry including a plurality of tracking wheels configured to enable the support gantry to traverse in a single axis direction and a first imaging assembly mounted on the support gantry, the first imaging assembly configured to capture image data comprising a plurality of image frames while the support gantry traverses parallel to a subject. They system also includes a control unit that directs movement and positioning of the support gantry and a processing and display device in communication with the first imaging assembly, the processing and display device configured to stitch and display the plurality of image frames as a single panoramic image. The processing and display device is configured to construct and display the panoramic image in real-time based on a traversing of the support gantry and the plurality of image frames obtained during the traversing. 
     In accordance with aspects of the present invention, the stitching includes the processing and display device calculating a motion between image frames along an X-axis of the traversing the support gantry, the processing and display device determining a size of an original panoramic image based on the calculated motion between image frames, the processing and display device downsampling the original panoramic image along the X-axis, the processing and display device determining a downsample size of the original panoramic image based on the downsampling, and the processing and display device downsampling the original panoramic image along the Y-axis. The downsampling can include a stitching tool selecting two or more overlapping lines between adjacent image frames, the stitching tool determining the traversing speed of the support gantry, the stitching tool performing a weighted operation to reduce parallax error, the stitching tool interpolating each of the two or more overlapping lines, and the stitching tool normalizing and summing the interpolated overlapping lines. The weighted operation can be a Gaussian formula of: W i(k) =e −0.5(Dist(k)/64)     2   , where Wi(k) is aGaussian weight and Dist(k) is a distance between overlapping lines for image frames. The stitching tool can perform the downsampling without a weighted operation. 
     In accordance with aspects of the present invention, the stitching comprises a correlation tool identifying a correlation of overlapping region(s) from adjacent images to find an inter frame motion. The identification of the correlation of overlapping region(s) can include the correlation tool selecting a search area size for searching for a correlation within each of the plurality of image frames, such that the search area size is smaller than a single image frame size, the correlation tool selecting a pattern image size to be used in the correlation search, such that the pattern image size is smaller than the search area size, the correlation tool comparing a pattern image to an area defined by the search area size for each of the plurality of image frames, and the correlation tool determining a correlation value based on the comparing. 
     In accordance with aspects of the present invention, the first imaging assembly includes a first imaging energy emitter that is positioned opposite a first imaging receptor, such that one of the first imaging energy emitter or the first imaging receptor is positioned at the first terminal end of the support gantry. The imaging system can further include a second imaging assembly that is positioned on the support gantry and comprising a second imaging energy emitter positioned that is opposite a second imaging receptor, such that one of the second imaging energy emitter or the second imaging receptor is positioned at the second terminal end of the support gantry. 
     In accordance with aspects of the present invention, the tracking wheels are configured to track a distance traversed by the support gantry. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       These and other characteristics of the present invention will be more fully understood by reference to the following detailed description in conjunction with the attached drawings, in which: 
         FIG. 1  is a diagrammatic illustration depicting the main components of a conventional G-arm medical imaging system in accordance with the present invention; 
         FIG. 2  is a diagrammatic illustration of a system for implementation of the present invention; 
         FIG. 3  is an example illustration of a plurality of image frames and a panoramic image created from the plurality of image frames, in accordance with the present invention; 
         FIG. 4  is a flowchart depicting an example stitching operation performed by the imaging system, in accordance with aspects of the present invention; 
         FIG. 5  is a diagrammatic illustration of identifying correlations between overlapping image frames, in accordance with aspects of the present invention; 
         FIG. 6  is a flowchart depicting an example correlation operation provided by the imaging system, in accordance with aspects of the present invention; 
         FIG. 7  is a flowchart depicting an example operation of the imaging system, in accordance with aspects of the present invention; and 
         FIG. 8  is a diagrammatic illustration of a high level architecture for implementing processes in accordance with aspects of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     An illustrative embodiment of the present invention relates to a method and system for combining individual overlapping medical images into a single undistorted panoramic image in real-time. The present invention identifies overlapping fields of view between a plurality of images, such that the overlaps can be used in a digital stitching process to create a digital panoramic image. Specifically, the present invention provides an image correlation algorithm for fine inter-frame translation that is adapted to find the overlapping region of a plurality of images, a correlation coefficient that is used to evaluate the similarity of overlapping region(s) of the plurality of images, and weighted blending is performed to produce a panorama image. In accordance with an example embodiment of the present invention, the weighted blending is the contribution factor of a pixel in a sub-image to panoramic/stitching image. 
     The combination of elements utilized in the present invention provide an optimized stitching implementation that is fast enough for real-time stitching and displaying of a digital panoramic image of a patient while the imaging system is moving along the patient. Additionally, the present invention produces robust and accurate panoramic images with quality and spatial resolution that is comparable to that of the individual images, without the utilization of down-sampling and masking to decrease the size of image and reduce the amount of computation (as required in traditional stitching methods and systems). The present invention, however, can utilize down-sampling and masking to further optimize and increase the speed of the stitching process, if desired but it is not required for the present invention to operate effectively. The combination of benefits and functionality provided by the present invention make the invention ideal for use in real-time during a fluoroscopic procedure. The real-time panoramic images provided by the present invention improve the effectiveness, reliability, and accuracy of the user performing the fluoroscopic procedure. 
       FIGS. 1 through 8 , wherein like parts are designated by like reference numerals throughout, illustrate an example embodiment or embodiments of an improved system for creating real-time panoramic images during a fluoroscopic procedure, according to the present invention. Although the present invention will be described with reference to the example embodiment or embodiments illustrated in the figures, it should be understood that many alternative forms can embody the present invention. One of skill in the art will additionally appreciate different ways to alter the parameters of the embodiment(s) disclosed, such as the size, shape, or type of elements or materials, in a manner still in keeping with the spirit and scope of the present invention. 
     The present invention includes a system and method for implementation with a medical imaging device. In particular, the present invention is configured to produce real-time panoramic images for use during medical procedures (e.g., such as fluoroscopic imaging procedures). As would be appreciated by one skilled in the art, imaging during a procedure can be implemented utilizing a collection of different imaging systems (e.g., C-arm, G-arm bi-plane fluoroscopic imager, etc.). An example of an imaging system for use in accordance with the present invention is depicted in  FIG. 1 . In particular,  FIG. 1  depicts the main components of a G-arm medical imaging system  100  which can be utilized during a fluoroscopic procedure. Although the imaging system  100  depicted in  FIG. 1  is a G-arm medical imaging system  100 , the illustrative example of a G-arm is for example purposes only and is not intended to limit the present invention to implementation with a G-arm device. For example, the present invention can be implemented on a C-arm or other imaging device. 
     Continuing with  FIG. 1 , the main components of the imaging system  100  include a movable stand or support gantry  102  (e.g., via tracking wheels  120 ), a radiation source  104  and radiation detector  106  configured for a frontal view (or anteroposterior view), a radiation source  108  (e.g., X-ray source) and radiation detector  110  (fluoroscopic imager or X-ray photon detector) configured for a lateral view, and a patient table  112  configured to hold a patient between the radiation sources  104 ,  108  and the radiation detectors  106 ,  110 . The movable stand or support gantry  102  provides the foundational framework in which each of the other components depicted in  FIG. 1  are attached to create the imaging system  100 . The radiation sources  104 ,  108  are configured to produce radiation (e.g., X-ray photons) for projection through a subject patient  114  (e.g., a patient) positioned on a patient table  112 . As would be appreciated by one skilled in the art, the radiation sources  104 ,  108  can include any kind of radiation sources utilized for imaging a patient. For example, the radiation sources  104 ,  108  can be electromagnetic radiation or x-radiation sources configured to produce X-rays. 
     In accordance with an example embodiment of the present invention, the imaging system  100  includes or is otherwise communicatively attached to a processing and display device  116  and a control logic device  118 . The control logic  118  is configured to receive input from the processing and display device  116  (e.g., via an input from a user) and transmit signals to control the radiation sources  104 ,  108 . In particular, the control logic  118  provides signals for operating the radiation sources  104 ,  108  and when to produce radiation. The radiation detectors  106 ,  110  are configured to electrically transform the received radiation, produced by the radiation sources  104 ,  108 , into detectable signals (e.g., raw image data). An example of a traditional radiation detector is a flat panel detector, which is a thin film transistor (TFT) panel with a scintillation material layer configured to receive energy from visible photons to charge capacitors of pixel cells within the TFT panel. The charges for each of the pixel cells are readout as a voltage data value to the processing and display device  206  as an image  216  of the patient (e.g., an X-ray image). As would be appreciated by one skilled in the art, each of the components within the imaging system  100  can include a combination of devices known in the art configured to perform the imaging tasks discussed herein. For example, an image intensifier is an alternative radiation detector that can be utilized in place of the radiation detectors. Additionally, the radiation sources  104 ,  108  and radiation detectors  106 ,  110  are positioned in a configuration to simultaneously the capture a posterior image of a patient and a lateral position of the patient (e.g., perpendicular sources and detectors as shown in  FIG. 1 ). 
     In accordance with an example embodiment of the present invention, the processing and display device  116  is configured to receive the raw image data from the radiation detectors  106 ,  110 , the raw image data including a plurality of limited field of view image frames  310  captured at the different locations at different points in time on a subject patient  312  located between the radiation sources  104 ,  108  and the radiation detectors  106 ,  110 . In particular, the processing and display device  116  receives the plurality of raw image data captured by the radiation detectors  106 ,  110  resulting from the radiation sources  104 ,  108 . The processing and display device  116  is configured to transform the raw image data for each of the plurality of image frames  310  into a single panoramic image  340 , as discussed in greater detail with respect to  FIGS. 3-6 . In short, the processing and display device  116  analyzes the plurality of image frames  310  to identify overlaps/correlations between adjacent image frames  310  and stitches together the image frames  310 , based on the identified overlaps/correlations into a non-parallax panoramic image. Thereafter, the single panoramic image  340  can be displayed to a user on a display device in real-time. 
       FIG. 2  depicts an illustrative computing system and/or device for implementing the steps in accordance with the aspects of the present invention. In particular,  FIG. 2  depicts a computing system and/or device implemented in accordance with the processing and display device  116  for the imaging system  100 . In accordance with an example embodiment, the processing and display device  116  is a combination of hardware and software configured to carry out aspects of the present invention. In particular, the processing and display device  116  can include a computing system with specialized software and databases designed for providing a method for optimizing reward-based campaigns. For example, the processing and display device  116  can be software installed on a computing device  204 , a web based application provided by a computing device  204  which is accessible by the imaging system  100 , a cloud based application accessible by computing devices, or the like. The combination of hardware and software that make up the processing and display device  116  are specifically configured to provide a technical solution to a particular problem utilizing an unconventional combination of steps/operations to carry out aspects of the present invention. In particular, the processing and display device  116  is designed to execute a unique combination of steps to provide a novel approach to stitching together a plurality of medical image frames  310  to produce a single panoramic image in real-time. 
     In accordance with an example embodiment of the present invention, the processing and display device  116  can include a computing device  204  having a processor  206 , a memory  208 , an input output interface  210 , input and output devices  212  and a storage system  214 . Additionally, the computing device  204  can include an operating system configured to carry out operations for the applications installed thereon. As would be appreciated by one skilled in the art, the computing device  204  can include a single computing device, a collection of computing devices in a network computing system, a cloud computing infrastructure, or a combination thereof. Similarly, as would be appreciated by one of skill in the art, the storage system  214  can include any combination of computing devices configured to store and organize a collection of data. For example, storage system  214  can be a local storage device on the computing device  204 , a remote database facility, or a cloud computing storage environment. The storage system  214  can also include a database management system utilizing a given database model configured to interact with a user for analyzing the database data. 
     Continuing with  FIG. 2 , the processing and display device  116  can include a combination of core components to carry out the various functions of the present invention. In accordance with an example embodiment of the present invention, the processing and display device  116  can include a stitching tool  216  and a correlation tool  218 . As would be appreciated by one skilled in the art, the stitching tool  216  and the correlation tool  218  can include any combination of hardware and software configured to carry out the various aspects of the present invention. In particular, each of the stitching tool  216  and the correlation tool  218  are configured to identify correlations between adjacent overlapping image frames  310  and stitching the image frames  310  together into a single panoramic image  340  in real-time. 
     In accordance with an example embodiment of the present invention, the stitching tool  216  is configured to manage the stitching process in accordance with the present invention. In particular, the stitching tool  216  is configured to receive a plurality of overlapping image frames  310  from the imaging system  100  and create a single panoramic image  340  from the plurality of image frames  310 . Any combination of stitching methodologies can be implemented by the stitching tool  216  to create the panoramic image  340 . An exemplary example of the stitching process implemented by the stitching tool  216  is discussed in greater detail with respect to  FIGS. 3-7 . 
     In accordance with an example embodiment of the present invention, the correlation tool  218  is configured to perform a correlation analysis via a correlation algorithm between two adjacent image frames  310 . In particular, the correlation tool  218  is configured to find an overlapping region of a plurality of image frames  310  and utilize a correlation coefficient to evaluate the similarities of the overlapping region(s) of the plurality of images. Thereafter, the correlation tool  218  can implement weighted blending to be utilized in the creation of a single panorama image  340  from the plurality of image frames  310 . In accordance with an example embodiment of the present invention, the weighted blending is a contribution factor of a pixel in a sub-image to panoramic/stitching image. For example, the correlation tool  218  can utilize a weighting profile, such as triangular, Gaussian, etc., to perform the weighted blending. As would be appreciated by one skilled in the art, any combination of correlation and blending algorithms can be utilized without departing from the scope of the present invention. For example, a correlation can be determined by calculating an overall image intensity difference between two images or using an attenuation map of bone structure to identify a natural marker to find the image translation between individual image frames  310 . An illustrative example of the correlation process implemented by the correlation tool  218  is discussed in greater detail with respect to  FIGS. 5 and 6 . 
     Returning to  FIG. 1 , in accordance with an example embodiment of the present invention, the support gantry  102  is configured with tracking wheels  120  to enable the support gantry  102 , and the components attached thereto, to be mobile. In particular, the tracking wheels  120  are configured to enable a user to push/pull the support gantry  102  along a single axis for purposes of traversing a span of a subject  114  located within the imaging system  100 . Additionally, in accordance with an example embodiment, the tracking wheels  120  and/or a portion of the support gantry  102  can be configured to maintain a traversing path in a single axis. For example, the tracking wheels  120  or another part of the support gantry  102  can be removably attached to a track to ensure that the support gantry  102  only traverses within a single axis (e.g., the X-axis). As would be appreciated by one skilled in the art, any suitable combination of mechanical devices can be utilized to enable the support gantry  102  to be mobile and is not limited to the use of tracking wheels  120 . In accordance with an example embodiment of the present invention, the tracking wheels  120  are configured with a tracking mechanism to provide tracking information related to location, distance traveled, speed, etc. The tracking mechanism is further configured to provide the tracking information to the processing and display device  116  for additional processing. 
     In operation, the imaging system  100  is configured to traverse a length of a subject  114  resting on a patient table  112  of the imaging system  100  (e.g., between the radiation sources  104 ,  108  and the radiation detectors  106 ,  110 ). Additionally, while the imaging system  100  is traversing the length of the subject  114 , the imaging system  100  is configured to capture a plurality of independent limited field of view and overlapping image frames  310  representing different portions of the subject  114 . In a simplified example, a first image frame  310  can capture a head/shoulder region of a subject  114 , a second image frame  310  can capture a torso region of a subject  114 , a third image frame  310  can capture a leg region of a subject  114 , and so on. Thereafter, the imaging system  100  is configured to transform the overlapping image frames  310  into a single undistorted non-parallax single panoramic image  340  (e.g., a head to toe image of a subject  114 ) by stitching together the image frames  310 . 
     The imaging system  100  begins the creation of the panoramic imaging process by initiating the radiation sources  104 ,  108  to generate radiation, directed at and through a patient  114 , to be received by radiation detectors  106 ,  110 . In accordance with an example embodiment of the present invention, during generation of the radiation, the support gantry  102  (and the radiation detector  304  attached thereto) traverses in a single axis direction (e.g., in response to pushing/pulling force applied by an operator). For example, the support gantry  102  and the components attached thereto can be pushed/pulled by an operator user (or through an automated mechanical means) causing the support gantry  102  to traverse along fixed path via the tracking wheels  120  on the support gantry  102 . 
     As the support gantry  102  traverses, the radiation detectors  106 ,  110  attached thereto will receive the radiation generated by the radiation sources  104  and generate periodic readouts of the received radiation (e.g., as raw image data). As would be appreciated by one skilled in the art, as the support gantry  102  is traversing, the corresponding raw image data captured by the radiation detectors  106 ,  110  will reflect the location of the subject  114  at the traversed location at that point in time. Simultaneous with the support gantry  102  traversing and the radiation detectors  106 ,  110  providing raw data readouts, the processing and display device  116  receives the raw image data from the radiation detectors  106 ,  110 . Based on the received raw image data, the processing and display device  116  is configured to transform the raw image data into a plurality of viewable image frames  310 . As would be appreciated by one skilled in the art, the raw data can be periodically sampled to create data for the plurality of independent image frames  310 . In accordance with an example embodiment of the present invention, each transmission of each independent collection of raw data (e.g., for each individual image) includes a respective location of the radiation detector  304  (e.g., according to a mechanical positioning of the support gantry  102 /tracking wheels  120 ) at the time that the raw data was captured. 
     In accordance with an example embodiment of the present invention, the raw image data is sampled at a rate such that the plurality of image frames  310  are overlapping images. Utilizing the determined motion of the traversing support gantry  102 , the processing and display device  306  creates a single non-parallax wide-view panoramic image  340  by stitching together the overlapping plurality of image frames  310 , as discussed in greater detail with respect to  FIGS. 3-6 . In accordance with an example embodiment of the present invention, the non-parallax panoramic image is stitched together based on identifying correlations between adjacent image frames  310 . In particular, the panoramic image is created by identifying the overlapping regions of the plurality of images and interpolating the images from an adjacent view utilizing a weighting profile. For example, the processing and display device  116  can utilize a Gaussian or triangular weighting profile to create the panoramic image. The imaging system  100  can update the panoramic image  340  on the fly in real-time as image frames  310  are received and stitched together with the previously received image frames  310 . 
       FIG. 3  depicts an exemplary representation of a plurality of overlapping image frames  310  captured by the imaging system  100  and to be utilized to create a single non-parallax panoramic image (e.g., via a stitching process). In particular,  FIG. 3  depicts a plurality of overlapping image frames  310  starting with the initial image frame  310  (I(0)) and continuing through image frames  310  (I(1) . . . , I(n−1), I(n)). The image frames  310  are acquired by a traversing imaging system  100 , as discussed with respect to  FIGS. 1, 2, and 7 . Image frame  310  (I(n)) represents a current image, image frame  310  (I(n−1)(represents a previous image frame  310 , and so on. The dimensions of the individual image frames  310  depicted in  FIG. 3  are designated as Wo×Ho. Similarly, the dimension of the combination of the plurality of overlapping image frames  310  (e.g., an original panoramic image  320 ) depicted in  FIG. 3  is designated with a size of (Wp×Wo).  FIG. 3  also depicts a X-axis and Y-axis indicating a traversing direction (e.g., the X-axis) and non-traversing direction (e.g., the Y-axis) of the support gantry  102  during operation of the present invention. 
     In operation, the stitching tool  216  utilizes a plurality of overlapping image frames  310 , such as the image frames  310  depicted in  FIG. 4  to create a single panoramic image  340  constructed in real-time from the overlapping image frames  310 . To reduce parallax errors and display the panoramic image  340  in real-time, the stitching tool  216  performs a downsampling blending process. In accordance with an example implementation of the present invention, the stitching tool  216  utilizes the process  400  from  FIG. 4  to perform the stitching process. In particular,  FIG. 4  depicts a process implemented by the processing and display device  116  by executing the stitching tool  216  to stitch together a plurality of overlapping image frames  310 . Initially, at step  402 , the processing and display device  116  receives a plurality of overlapping image frames  310 , such as the image frames  310  as depicted in  FIG. 3 , in real-time as the support gantry  102  traverses over a subject  114 . 
     At step  404  the stitching tool  216  determines a traversing speed (e.g., via the tracking wheels  120 ) of the support gantry  102  for each adjacent set of image frames  310 . In particular, the stitching tool  216  calculates a motion dx(n) along X-axis between current frame I(n) and previous frame I(n−1). As would be appreciated by one skilled in the art, this process is repeated for each subsequent image frame  310  and each preceding image frame  310  (e.g., dx(n), dx(n−1), dx(n−2), . . . etc.) using motion data obtained from the tracking wheels  120 . In accordance with an example embodiment of the present invention, the motion dx(n) is determined based on the tracking information provided by the tracking wheels  120  (or one of the tracking wheels  120 ). As would be appreciated by one skilled in the art, because the support gantry  102  traverses a single axis (e.g., the X-axis), the motion change along Y-axis does not need to be calculated. 
     At step  406  the stitching tool  216  determines an original panoramic image size  320  for the combined plurality of image frames  310 . In particular, the stitching tool  216  determines the original panoramic image size  320  by utilizing the motion data collected in step  404 . In accordance with an example embodiment of the present invention, the motion data (e.g., dx(n), dx(n−1), dx(n−2), . . . , dx(1),) is utilized within an algorithm: W p =Max{Σ i   n dx(i)}−Min{Σ i   n dx(i)}+W o  to determine the original panoramic image size  320 . As would be appreciated by one skilled in the art, any combination of algorithms can be utilized in determining the dimensions of the original panoramic image size  320 , without departing from the scope of the present invention. In the example of  FIG. 3 , the original panoramic image size  320  is Wp×Ho. As would be appreciated by one skilled in the art, because the support gantry  102  only traverses in a single axis, the dimension for the other axis is known (e.g., based on individual image frame dimensions). In  FIG. 3 , the constant axis is represented by dimension Ho. 
     At steps  408 - 410  the stitching tool  216  performs a downsampling process on the original panoramic image  320  along the traversing axis of the support gantry  102  (e.g., the X-axis direction) to obtain Pm(n)  330 . At step  408  the stitching tool  216  performs a weighting operation to reduce parallax error. In particular, the stitching tool  216  selects the nearest lines (Li(0), Li(1), . . . , Li(N)) corresponding to the individual image frames I(x) (e.g., I(0) . . . I(n)) and assigns Li(k) to a Gaussian weight Wi(k) in the weighted algorithm of: W i(k) =e −0.5(Dist(k)/64)     2   . Dist(k) identifies the distance between Li and Li(k) based on the traversing speed of the imaging system  100  (e.g., determined from the tracking wheels  120 ). 
     At step  410 , based on the results of the weighting in step  408 , the stitching tool  216  interpolates each line Li(k) to Lpi(k) to obtain the result line Li (as depicted in Pm(n)  330  of  FIG. 3 ) after normalizing and summing all lines Lpi(k). As would be appreciated by one skilled in the art, any combination of interpolation and normalization methods can be utilized herein. As a result of the steps  408 - 410 , the stitching tool  216  derives Pm(n)  330  including the line Li with the dimensions of Wd×Ho, as depicted in  FIG. 3 ). 
     At step  412  the stitching tool  216  performs downsampling on Pm(n)  330  along the non-traversing axis (e.g., the Y-axis direction). Unlike in steps  408 - 410 , there is no weight assignment needed when downsampling in the non-traversing axis because no motion occurred in that direction. In accordance with an example embodiment of the present invention, and to improve efficiency, the stitching tool  216  transposes the image frames  310  to calculate non-traversing axis motion and blend with the same method discussed with respect to steps  406 - 408 . The result of the downsampling in the non-traversing axis is the final displaying panoramic image  340  (to be displayed to a user by the processing and display device  116 ).  FIG. 3  depicts Disp(n) representing the final displaying panoramic image  340  resulting from the steps  402 - 412  (e.g., downsampling blending when stitching image frames  310 ). The resulting panoramic image  340  is much smaller than the original panoramic image  320  which, as depicted in  FIG. 3 , has dimensions of Wd×Hd. 
     In accordance with an example embodiment of the present invention, the processing and display device  116 , as implemented by the correlation tool  218 , applies a weighting blending profile (e.g., triangular or Gaussian weighting) to the stitching process. The weighted blending is the contribution factor of a pixel in a sub-image to panoramic/stitching image, as discussed in greater detail with respect to  FIGS. 5 and 6 . 
       FIG. 5  depicts two image frames  310  from a plurality of image frames  310  obtained as discussed with respect to  FIGS. 1, 2, and 7 . In particular,  FIG. 5  depicts a first image frame  310   a  obtained by the processing and display device  116  at a first point in time and a second image frame  310   b  obtained by the processing and display device  116  at a second point in time.  FIG. 5  also depicts a X-axis and Y-axis indicating a traversing direction (e.g., the X-axis) and non-traversing direction (e.g., the Y-axis) of the support gantry  102  during operation of the present invention. The image frame  310   b  (or I(n)) represents an image frame  310  at a current point in time while the image frame  310   a  (or I(n−1)) represents an image frame  310  at the previous point in time to the image frame  310   b . The motion of the support gantry  102  between the image frame  310   a  and the image frame  310   b  is designated by the dx(n)′ value. Additionally, as reflected in  FIG. 5 , the image frames  310   a  and  310   b  have an overlapping area reflected by the shaded area. 
       FIG. 6  depicts the process  600  for identifying correlations between two overlapping image frames  310 . At step  602  the correlation tool  218  identifies the overlapping areas for two adjacent image frames  310 . In accordance with an example embodiment of the present invention, the overlapping areas are identified based on a determination of the motion of the support gantry  102  (dx(n)) between captures of the image frames and a known image frame size. As discussed herein, the motion dx(n) can be calculated based on the amount of time/traverse speed of the tracking wheels  120  or other method known in the art. In the example depicted in  FIG. 5 , the overlapping areas of the image frames  310   a  and  310   b  is represented by the shaded area of each respective image frame  310   a ,  310   b.    
     At step  604  the correlation tool  218  selects a pattern image  510  within the overlapping area of the first image frames  310   a  (or I(n−1)) for correlation identification. The pattern image  510  is an area smaller than the overlapping area and is designed to improve the efficiency of the correlation search (rather than searching the entirety of the overlapping areas). As would be appreciated by one skilled in the art, the size of the pattern image  510  can be automatically determined by the correlation tool  218  or it can be a user defined value. In the example depicted in  FIG. 5 , the pattern image  510  is designed in image frame  310   a  as P(n−1). 
     At step  606  the correlation tool  218  searches the second image frame  310   b  (or I(n)/current image frame  310 ) for a pattern image  520  (or P′(n)) that mostly closely represents the pattern image  510  from the image frame  310   a  by comparing a correlation value. In accordance with an example embodiment of the present invention, the searching performed in step  606  is limited to a search area  530  which is an area within the overlapping area with a smaller dimension. As would be appreciated by one skilled in the art, the size of the search area  530  can be automatically determined by the correlation tool  218  or it can be a user defined value. For example, the search area  530  can be determined based on a current image frame rate and the tracking wheel  120  speed. By restricting the search to the search area  530 , the correlation tool  218  is able to more efficiently identify the correlated areas. In an example, the image frame  310  size is 1024 pixel(width) by 1024 pixel(height), the pattern image  510  size is 256 pixel(width) and 256 pixel(height), and the search area  530  size is 512 pixel(width)×512 pixel(height). 
     In accordance with an example embodiment of the present invention, the correlation tool  218  utilizes the following algorithm to calculate the correlation between the pattern image  510  (P(n−1)) and the pattern image  520  (P′(n)) in the current image frame  310   b . (I(n)): 
     
       
         
           
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     The resulting Cor value can range from 0 to 1.0, while the closer that the Cor value is to 1.0, the higher correlation exists between the two patterns/areas. In the algorithm, N is the pixel number in the pattern area, P x (i) or P x ′(i) identifies the pixel value in the image frame  310  (I(x)). As would be appreciated by one skilled in the art, any combination of correlation algorithms can be utilized without departing from the scope of the present invention. 
     As depicted in  FIG. 5 , Cn(x, y) is the center of the Pn(x, y) area which is most likely to the pattern area  510  (P(n−1)). However, its accuracy is in pixel. Thus, to improve the accuracy, at step  608 , the correlation tool  218  utilizes an interpolation method to get the final CFn(x, y) in sub pixel accuracy as follow: 
     
       
         
           
             
               
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     Where P Right (i) with center C n (x+1,y), and P Left (i) with center C n (x−1,y). At step  610 , after calculating the sub pixel CFn(x,y), the correlation tool  218  calculates motion dx(n) for sub pixel accuracy using the following algorithm: dx(n)=CF n (x)−CF n-1 (x). 
     Utilizing the above-noted correlation identification, weighted blending, and stitching methodologies and system, the imaging system  100  is able to produce the single non-parallax panoramic image  340  in real-time (generated and updated as the support gantry  102  moves) for use during a fluoroscopic procedure. As such, the present invention provides an improvement in the functioning of the computer itself in that it enables the real-time stitching and displaying of images without requiring downsampling. The present invention also thereby is an improvement to existing digital medical image processing technologies. In accordance with an example embodiment of the present invention, the stitching method to produce the panoramic image is fully automated without any user input required. The stitching image frames  310  together and displaying the stitched panoramic image in real-time while the support gantry  102  traverses along the subject  114 . In accordance with an example embodiment of the present invention, as raw image data/image frames  310  are received by the processing and display device  116 , the panoramic image  340  is updated on the fly to produce the real time display. As would be appreciated by one skilled in the art, the stitching can be performed utilizing any stitching methods and systems known in the art to combine a plurality of images into a single image (e.g., through interpolating, blending, etc.). 
       FIG. 7  depicts an example overall operation of the imaging system  100  in accordance with the present invention. In particular,  FIG. 7  depicts a process  700  operation for utilization of a fluoroscopic imaging system. At step  702  a fluoroscopic imaging system  100 , as discussed with respect to  FIGS. 1-6 , is activated. At step  704  a processing and display device  116  receives raw image data including a plurality of limited field of view image frames  310 , each captured at the position of the support gantry  102  relative a subject  114  patient located between the radiation sources  104 ,  108  and the radiation detectors  106 ,  110 . Additionally, the position of the support gantry  102  during the image capture is obtained by the processing and display device  116  (e.g., based on motion data from the tracking wheels  120 ). At step  706  the processing and display device transforms the raw image data into displayable image frames  310  of the subject patient on the fly. At step  708  the processing and display device  116  stitches together the displayable images, based on the position of the support gantry  102 , into a non-parallax panoramic image  340 . At step  710  the processing and display device displays the non-parallax panoramic image (e.g., panoramic image  340 ) to a user in real time (e.g., for use during a fluoroscopic procedure). Relying on the real-time panoramic image, the user can perform a fluoroscopic procedure, which reduces a radiation dosage applied to the patient. 
     Any suitable computing device can be used to implement the computing devices (e.g., processing and display device  116 ) and methods/functionality described herein and be converted to a specific system for performing the operations and features described herein through modification of hardware, software, and firmware, in a manner significantly more than mere execution of software on a generic computing device, as would be appreciated by those of skill in the art. One illustrative example of such a computing device  800  is depicted in  FIG. 8 . The computing device  800  is merely an illustrative example of a suitable computing environment and in no way limits the scope of the present invention. A “computing device,” as represented by  FIG. 8 , can include a “workstation,” a “server,” a “laptop,” a “desktop,” a “hand-held device,” a “mobile device,” a “tablet computer,” or other computing devices, as would be understood by those of skill in the art. Given that the computing device  800  is depicted for illustrative purposes, embodiments of the present invention may utilize any number of computing devices  800  in any number of different ways to implement a single embodiment of the present invention. Accordingly, embodiments of the present invention are not limited to a single computing device  800 , as would be appreciated by one with skill in the art, nor are they limited to a single type of implementation or configuration of the example computing device  800 . 
     The computing device  800  can include a bus  810  that can be coupled to one or more of the following illustrative components, directly or indirectly: a memory  812 , one or more processors  814 , one or more presentation components  816 , input/output ports  818 , input/output components  820 , and a power supply  824 . One of skill in the art will appreciate that the bus  810  can include one or more busses, such as an address bus, a data bus, or any combination thereof. One of skill in the art additionally will appreciate that, depending on the intended applications and uses of a particular embodiment, multiple of these components can be implemented by a single device. Similarly, in some instances, a single component can be implemented by multiple devices. As such,  FIG. 8  is merely illustrative of an exemplary computing device that can be used to implement one or more embodiments of the present invention, and in no way limits the invention. 
     The computing device  800  can include or interact with a variety of computer-readable media. For example, computer-readable media can include Random Access Memory (RAM); Read Only Memory (ROM); Electronically Erasable Programmable Read Only Memory (EEPROM); flash memory or other memory technologies; CDROM, digital versatile disks (DVD) or other optical or holographic media; magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices that can be used to encode information and can be accessed by the computing device  800 . 
     The memory  812  can include computer-storage media in the form of volatile and/or nonvolatile memory. The memory  812  may be removable, non-removable, or any combination thereof. Exemplary hardware devices are devices such as hard drives, solid-state memory, optical-disc drives, and the like. The computing device  800  can include one or more processors that read data from components such as the memory  812 , the various I/O components  816 , etc. Presentation component(s)  816  present data indications to a user or other device. Exemplary presentation components include a display device, speaker, printing component, vibrating component, etc. 
     The I/O ports  818  can enable the computing device  800  to be logically coupled to other devices, such as I/O components  820 . Some of the I/O components  820  can be built into the computing device  800 . Examples of such I/O components  820  include a microphone, joystick, recording device, game pad, satellite dish, scanner, printer, wireless device, networking device, and the like. 
     As utilized herein, the terms “comprises” and “comprising” are intended to be construed as being inclusive, not exclusive. As utilized herein, the terms “exemplary”, “example”, and “illustrative”, are intended to mean “serving as an example, instance, or illustration” and should not be construed as indicating, or not indicating, a preferred or advantageous configuration relative to other configurations. As utilized herein, the terms “about”, “generally”, and “approximately” are intended to cover variations that may existing in the upper and lower limits of the ranges of subjective or objective values, such as variations in properties, parameters, sizes, and dimensions. In one non-limiting example, the terms “about”, “generally”, and “approximately” mean at, or plus 10 percent or less, or minus 10 percent or less. In one non-limiting example, the terms “about”, “generally”, and “approximately” mean sufficiently close to be deemed by one of skill in the art in the relevant field to be included. As utilized herein, the term “substantially” refers to the complete or nearly complete extend or degree of an action, characteristic, property, state, structure, item, or result, as would be appreciated by one of skill in the art. For example, an object that is “substantially” circular would mean that the object is either completely a circle to mathematically determinable limits, or nearly a circle as would be recognized or understood by one of skill in the art. The exact allowable degree of deviation from absolute completeness may in some instances depend on the specific context. However, in general, the nearness of completion will be so as to have the same overall result as if absolute and total completion were achieved or obtained. The use of “substantially” is equally applicable when utilized in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result, as would be appreciated by one of skill in the art. 
     Numerous modifications and alternative embodiments of the present invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode for carrying out the present invention. Details of the structure may vary substantially without departing from the spirit of the present invention, and exclusive use of all modifications that come within the scope of the appended claims is reserved. Within this specification embodiments have been described in a way which enables a clear and concise specification to be written, but it is intended and will be appreciated that embodiments may be variously combined or separated without parting from the invention. It is intended that the present invention be limited only to the extent required by the appended claims and the applicable rules of law. 
     It is also to be understood that the following claims are to cover all generic and specific features of the invention described herein, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.