Patent Publication Number: US-8523433-B2

Title: Handheld X-ray system interface device and method

Description:
BACKGROUND OF THE INVENTION 
     The subject matter disclosed herein relates to X-ray imaging systems and more particularly to X-ray imaging systems using a handheld interface device. 
     X-ray systems are widely employed in medical environments, such as hospitals. Typically, where possible the X-ray technician is positioned away from the location of exposure, and often behind a shielded barrier to avoid or reduce exposure to radiation. Often the X-ray systems include an exposure switch, or handswitch, attached to a cord, which is in signal communication with a control console of the X-ray system and that allows the technician to make the exposure from a distance (e.g., by pressing a button on the handswitch), sometimes outside of the examination room. However, when the technician is not physically in close proximity to the X-ray system it may be difficult for the technician to know the status of and to interact with the X-ray system and/or the patient. 
     Further, the extension of the cord attached to the handswitch presents additional problems. For example, the extended cord may interfere with or disrupt other equipment within the room (e.g., life support equipment). Also, the cord may become damaged over time due to repeated stretching. Thus, the need for a handswitch arrangement to overcome these difficulties. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In accordance with one aspect of the invention, an X-ray system comprises an imaging system. The image data acquisition system includes a source of X-ray radiation, an X-ray image receptor, control circuitry for controlling the source of X-ray radiation, and a wireless interface. The X-ray system also includes a handheld interface device configured to communicate wirelessly with the imaging system. The imaging system is configured to communicate system operational data to the handheld interface device. 
     In accordance with aspect of the invention, an X-ray system comprises a handheld X-ray interface device. The handheld X-ray interface device includes a wireless interface for communicating with an imaging system and for receiving system operational data from the imaging system. The handheld X-ray interface device is configured to provide a user detectable indication of the imaging system operational status based upon the received data. 
     In accordance with a further aspect of the invention, a method for operating a handheld X-ray interface device includes establishing wireless communication between an imaging system and a handheld interface device, where the imaging system includes a source of X-ray radiation, an X-ray image receptor, control circuitry for controlling the source of X-ray radiation, and a first wireless interface. The handheld interface device comprises a second wireless interface for communicating wirelessly with the imaging system. The method also includes communicating system operational data from the imaging system to the handheld interface device. The method further includes providing a user detectable indication of the imaging system operational status based upon the received data. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein: 
         FIG. 1  is a perspective view of a fixed X-ray system, equipped in accordance with aspects of the present technique; 
         FIG. 2  is a perspective view of a mobile X-ray system, equipped in accordance with aspects of the present technique; 
         FIG. 3  is a diagrammatical overview of the X-ray systems in  FIGS. 1 and 2 ; 
         FIG. 4  is a perspective view of a handheld interface device in  FIGS. 1 and 2 ; 
         FIG. 5  is a perspective view of another handheld interface device in  FIGS. 1 and 2 ; 
         FIG. 6  is a diagrammatical overview of the handheld interface device in  FIG. 4 ; 
         FIG. 7  is a diagrammatical overview of the handheld interface device in  FIG. 5 ; 
         FIG. 8  is a diagrammatical overview of system operational data received by handheld interface devices, in accordance with aspects of the present technique; 
         FIG. 9  is a diagrammatical overview of user-input and user-input commands received and transmitted by handheld interface devices, in accordance with aspects of the present technique; 
         FIG. 10  is a perspective view of an imaging system and handheld interface device outside of a desired distance from each other, in accordance with aspects of the present technique; 
         FIG. 11  is a perspective view of the imaging system following the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 12  is a perspective view of movement of an X-ray source of the imaging system by the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 13  is a perspective view of the imaging system conducting an imaging sequence in response to the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 14  is a perspective view of determining various exposure parameters using the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 15  is a perspective view of determining orthogonality between the X-ray source and the image receptor, in accordance with aspects of the present technique; 
         FIG. 16  is perspective view of various patient data displayed on the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 17  is a perspective view of selection of desired area for imaging using the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 18  is a flow diagram of a method for operating the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 19  is a flow diagram of another method for operating the handheld interface device, in accordance with aspects of the present technique; 
         FIG. 20  is a flow diagram of a method for viewing patient data on the handheld interface device, in accordance with aspects of the present technique; and 
         FIG. 21  is a flow diagram of a method for tracking the location of the handheld interface device, in accordance with aspects of the present technique. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring generally to  FIG. 1 , an X-ray system is represented, referenced generally by reference numeral  10 . In the illustrated embodiment, the X-ray system  10  may be a digital or analog X-ray system. The X-ray system  10  is designed both to acquire original images or image data and to process the image data for display (in a digital X-ray system) in accordance with the present technique. 
     In the embodiment illustrated in  FIG. 1 , the X-ray system  10  includes an imaging system  12 . The imaging system  12  includes an overhead tube support arm  14  for positioning a radiation source  16 , such as an X-ray tube, and a collimator  18  with respect to a patient  20  and an image receptor  22 . In analog X-ray systems  10 , the image receptor  22  may include a radiographic film and cassette, phosphorescent screen and computed radiography cassette, or other device. In digital X-ray systems, the image receptor  22  may include a digital X-ray detector. The imaging system  12  may also include a camera  24  to help facilitate the positioning of the radiation source  16  and collimator  18 . Moreover, in one embodiment, the imaging system  12  may be used in consort with one or both of a patient table  26  and a wall stand  28  to facilitate image acquisition. Particularly, the table  26  and the wall stand  28  may be configured to receive image receptor  22 . For instance, image receptor  22  may be placed on an upper, lower or intermediate surface of the table  26 , and the patient  20  (more specifically, an anatomy of interest of the patient  20 ) may be positioned on the table  26  between the image receptor  22  and the radiation source  16 . Also, the wall stand  28  may include a receiving structure  30  also adapted to receive the image receptor  22 , and the patient  20  may be positioned adjacent the wall stand  28  to enable the image or image data to be acquired via the image receptor  22 . The receiving structure  30  may be moved vertically along the wall stand  28 . 
     Also depicted in  FIG. 1 , the imaging system  12  includes a workstation  32  and display  34 . In one embodiment, the workstation  32  may include or provide the functionality of the imaging system  12  such that a user  36 , by interacting with the workstation  32  may control operation of the source  16  and detector  22  (in a digital X-ray system  10 ). In other embodiments, the functions of the imaging system  12  may be decentralized, such that some functions of the imaging system  12  are performed at the workstation  32 , while other functions are performed by another component of the X-ray system  10 , such as a handheld interface device  38 . The handheld interface device  38  is configured to be held by a user  36  and to communicate wirelessly with the imaging system  12 . The handheld interface device  38  is also configured to prepare the imaging system  12  for an exposure and to initiate an exposure. The imaging system  12  is configured to wirelessly communicate system operational data to the handheld interface device  38  and the handheld interface device  38  is configured to provide a user detectable indication of the operational status based on the data. In one embodiment, the handheld interface device  38  (e.g.,  40 ) is simply designed to prepare and initiate an exposure, as well as to receive system operational data and to provide an indication of the data. It is noted that the imaging system  12  and handheld interface device  38  may utilize any suitable wireless communication protocol, such as an IEEE 802.15.4 protocol, an ultra wideband (UWB) communication standard, a Bluetooth communication standard, or any IEEE 802.11 communication standard. 
     In another embodiment, the handheld interface device  38  (e.g.,  42 ) is configured to receive a user-input command for operation of the imaging system  12  (e.g., changing X-ray source settings or moving the receiving structure  30  along the wall stand  28 ) prior to initiation of an X-ray exposure sequence and to wirelessly transmit the command to the imaging system  12 . For example, the imaging system  12  may include a speaker  44  to transmit patient-audible commands to the patient  20  in response to a signal from the handheld interface device  42 . The speaker  44  may be located on the operator workstation  34 , near the radiation source  16 , in the table  26 , or another location. In response to wirelessly receiving the command from the handheld interface device  42  the imaging system  12  executes the command. Also, the handheld interface device  42  includes a user-viewable screen  46  and is configured to receive and display patient data on the screen  46 . The imaging system  12  is configured to communicate patient data or instructions to the handheld interface device  42 . In one embodiment, the workstation  32  may be configured to function as a server of instructions and/or content on a network  48  of the medical facility, such as a hospital information system (HIS), a radiology information system (RIS), and/or picture archiving communication system (PACS), and to provide these instructions and/or content to the handheld interface device  42 . Alternatively, the network  48  may wirelessly communicate directly with the handheld interface device  42 . 
     Further, the handheld interface device  42  may be configured to be tracked by the imaging system  12 . The imaging system  12  is configured to track the location and/or movement of the handheld interface device  42  and to use the location and/or movement as input to control at least one function of the system  12  (e.g., movement of the X-ray source  16 ). 
     In one embodiment, the imaging system  12  may be a stationary system disposed in a fixed X-ray imaging room, such as that generally depicted in and described above with respect to  FIG. 1 . It will be appreciated, however, that the presently disclosed techniques may also be employed with other imaging systems, including mobile X-ray units and systems, in other embodiments. 
     For instance, as illustrated in the X-ray system of  FIG. 2 , the imaging system  12  may be moved to a patient recovery room, an emergency room, a surgical room, or any other space to enable imaging of the patient  20  without requiring transport of the patient  20  to a dedicated (i.e., fixed) X-ray imaging room. The imaging system  12  includes a mobile X-ray base station  50  and image receptor  22 . As mentioned above, the X-ray system  10  may be digital or analog. In one embodiment, a support arm  52  may be vertically moved along a support column  54  to facilitate positioning of the radiation source  16  and collimator  18  with respect to the patient  20 . Further, one or both of the support arm  52  and support column  54  may also be configured to allow rotation of the radiation source  16  about an axis. The X-ray base station  50  may also include camera  24  to assist in positioning of the radiation source  16  and collimator  18 , as well as speaker  44  to transmit patient-audible commands as described above. In addition, the X-ray base station  50  includes a speaker located either on a base unit  56 , the column  54 , or the arm  52 , or another location of the X-ray base station  50 . Further, the X-ray base station  50  has a wheeled base  58  for movement of the station  50 . 
     The patient  20  may be located on a bed  60  (or gurney, table or any other support) between the X-ray source  24  and the image receptor  22  and subjected to X-rays that pass through the patient  20  and are received by either a film, phosphorescent screen, or other medium. During an imaging sequence using the digital X-ray system  10 , the detector  22  receives X-rays that pass through the patient  20  and transmits imaging data to a base unit  56 . The detector  22  is in communication with the base unit  56 . The base unit  56  houses systems electronic circuitry  62  that acquires image data from the detector  22  and that, where properly equipped, may process the data to form desired images. In addition, the systems electronic circuitry  62  both provides and controls power to the X-ray source  16  and the wheeled base  58  in either the digital or analog X-ray system  10 . The base unit  56  also has the operator workstation  32  and display  34  that enables the user  36  to operate the X-ray system  10 . The operator workstation  32  may include buttons, switches, or the like to facilitate operation of the X-ray source  16  and detector  22 . 
     Similar to the X-ray system  10  in  FIG. 1 , functions of the imaging system  12  may be performed by the handheld interface device  38 . As described above, the imaging system  12  and the handheld interface device  38  are configured to communicate wirelessly with each other. In addition, the handheld interface device  38  can be configured to communicate wirelessly with the medical facility network  48 , as described above. As above, the user  36  may utilize the handheld interface device  40  designed to prepare and initiate an exposure, as well as to receive system operational data and to provide an indication of the data. Alternatively, the user  36  may utilize the handheld interface device  42 , described above, to input user commands for operation of the imaging system  12  (e.g., the movement of the X-ray base station  50 ). In addition, the handheld interface device  42  includes screen  46  for the display of patient data, image data (in digital systems  10 ), instructions, as well as other information. Further, the handheld interface device  42  may be configured to be tracked, as described above. Tracking of the handheld interface device  42  may provide input to the X-ray base station  50  to follow the handheld interface device  42  as described below. The X-ray base station  50  has a holder or cradle  64  for the handheld interface device  38  when the device  38  is not in use. The cradle  64  may be configured to recharge the battery of the handheld interface  38 , either through conductive charge contacts or with a contactless method such as inductive or capacitive charging. 
       FIG. 3  illustrates diagrammatically the X-ray systems  10  described in  FIGS. 1 and 2 , in particular, digital X-ray systems  10 , although some of the below description applies to analog X-ray systems  10  as well. As illustrated in  FIG. 3 , the X-ray system  10  includes the source of X-ray radiation  16  positioned adjacent to the collimator  18 . A light source  66 , also known as a collimator light, is positioned between the X-ray source  16  and the collimator  18 . The collimator  18  permits a stream of radiation  68  or light to be directed to a specific region in which an object or subject, such as the patient  20 , is positioned. A portion  70  of the radiation passes through or around the subject and impacts the image receptor or digital X-ray detector  22 . As will be appreciated by those skilled in the art, the detector  22  in digital X-ray systems  10  converts the X-ray photons received on its surface to lower energy photons, and subsequently to electric signals, which are acquired and processed to reconstruct an image of the features within the subject. The collimator light  66  in the collimator  18  directs light onto the same area where the X-ray photons will pass and can be used to position the patient  20  before exposure. The collimator light  66  can be turned on and off with a user input on the imaging system  12  or on the handheld interface device  38 . 
     Moreover in digital X-ray systems, the detector  22  is coupled to a detector controller  72  which commands acquisition of the signals generated in the detector  22 . The detector controller  26  may also execute various signal processing and filtration functions, such as for initial adjustment of dynamic ranges, interleaving of digital image data, and so forth. The detector controller  26  is responsive to signals from control circuitry  74  communicated wirelessly via a wireless interface  76 . In general, the control circuitry  74  commands operation of the imaging system  12  to execute examination protocols and to process acquired image data (in digital X-ray systems  10 ). In the present context, the control circuitry  74  also includes signal processing circuitry, typically based upon a programmed general purpose or application-specific digital computer; and associated devices, such as optical memory devices, magnetic memory devices, or solid-state memory devices, for storing programs and routines executed by a processor of the computer to carry out various functionalities, as well as for storing configuration parameters and image data; interface circuits; and so forth. 
     In both digital and analog X-ray systems  10 , the radiation source  16  is controlled by the control circuitry  74  which controls signals for examination sequences. For example, the control circuitry  74  can inhibit the operation of the radiation source  16  if the correct examination conditions are not in place. In addition, the control circuitry  74  controls a power supply  78  which supplies power to the radiation source  16 , light source  66 , camera  24 , as well the control circuitry  74 . Interface circuitry  80  facilitates the provision of power to the radiation source  16 , light source  66 , camera  24 , and control circuitry  74 . The power supply  78  also provides power to a mobile drive unit  82  (in mobile X-ray systems) to drive the movement of the wheeled base  58  of the X-ray base station  50 . 
     In the embodiment illustrated in  FIG. 1 , the control circuitry  74  is linked to at least one output device, such as the display or printer  34 . The output device may include standard or special purpose computer monitors and associated processing circuitry. One or more operator workstations  34  may be further linked in the system for outputting system parameters, requesting examinations, viewing images (in digital X-ray systems  10 ), and so forth. In general, displays, printers, workstations, and similar devices supplied within the system may be local to the imaging components, or may be remote from these components, such as elsewhere within an institution or hospital, or in an entirely different location, linked to the imaging system  12  via one or more configurable networks, such as the Internet, virtual private networks, and so forth. The control circuitry  74  may also be linked to the speaker  44  which provides audible signals such as locator signals or patient-audible commands. 
     Via the wireless interface  76  the imaging system  12  communicates wirelessly with the handheld interface device  38 . The control circuitry  74  provides the handheld interface device  38  system operational data (e.g., inhibit of operation of radiation source), images reconstructed from image data from the detector  22  (in digital X-ray systems  10 ), images of the patient  20  generated by the camera  24 , and patient data, as well as other information. The handheld interface device  38  wirelessly communicates a signal to prepare for and initiate an exposure and other commands for operation of the imaging system  12 , as well the location and/or movement of the device  38  relative to the system  12 . Besides receiving patient data and/or instructions from the imaging system  12 , the handheld interface device  38  wirelessly receives patient information and/or instructions (e.g., imaging sequences to be performed) from the medical facility&#39;s network  48 . The medical facility network  48  includes PACS  84 , RIS  86 , and/or HIS  88  to provide the information and/or instructions. The network  48  may also communicate the patient information and/or instructions to imaging system  12 , which may then provide the information and/or instructions to the handheld interface device  38 . 
     As mentioned above, the handheld interface device  38  may include a simple embodiment of the device  40  to prepare for and initiate an exposure, as well as to receive system operational data and to provide an indication of the data. In addition, the handheld interface device  40  is configured to provide user detectable indications of the operational status of the imaging system  12 .  FIG. 4  illustrates the handheld interface device  40  of  FIGS. 1 and 2 . The handheld interface device  40  includes an exterior housing  90  that is suitably dimensioned to fit in the hand of the user. The handheld interface device  40  can be configured to be paired with a single X-ray system  10 . The handheld interface device  40  is configured to provide user detectable indications of the operational status of the imaging system  12 . The handheld interface device  40  includes a prepare/exposure push button  92  located at the top  94  of the device  40 . The prepare/exposure button  92  may operate in a variety of ways. In one embodiment, pressing the button  92  a first time may prepare the X-ray system  10  for an exposure (i.e., the rotor encasing the radiation source  16  begins spinning). Pressing the button  92  a second time may initiate the exposure by the X-ray system  10 . The button  92  may be inhibited from being pressed the second time if the X-ray system  10  has not finished preparations for the exposure. Alternatively, the button  92  may be partially pressed to a first position to prepare the X-ray system  10  for the exposure and further pressed to a second position to initiate the exposure. The button  92  may be inhibited from being pressed to the second position if the X-ray system  10  has not finished preparations for the exposure. In either embodiment, the button  92  is configured to not command the system to initiate an exposure when the operation of X-ray source  16  is inhibited. The handheld interface device  40  also includes a collimator light button  96  disposed on the exterior housing  90 . Pressing the collimator light button  96  may command the system to activate or deactivate the collimator light  66 . The handheld interface device  40  is configured to go to sleep when not in use. Pressing the prepare/exposure  92  and/or collimator light button  96  may also shift the device  40  from sleep mode to operational mode. In other embodiments, the handheld interface device  40  may include additional buttons for other features. 
     The handheld interface device  40  may also include one or more light emitting diodes (LEDs) to indicate the operational status of the imaging system  12 . For example, the handheld interface device  40  may include a power status (battery status) LED  98  to indicate the power level of the device  40 . The power status LED  98  may indicate the power status of the device  40  in a variety of ways. For example, the power status LED  98  may only illuminate when the device  40  has sufficient power. If the device  40  has low power, the LED  98  may blink or not be illuminated. Alternatively, the LED  98  may only illuminate when the power of the handheld interface device  40  is low. In a further alternative, the LED  98  may illuminate a specific color for a specific power status of the device  40 , such as green for sufficient power and red for low power. The handheld interface device  40  can also include a charge status LED  100  for the battery or power supply  78  that powers the X-ray source  16  and/or mobile drive unit  82  of the imaging system  12 . The LED  100  may be designed to function similarly to the power status LED  98  to indicate the status of the power supply  78 . The handheld interface device  40  also includes an X-ray exposure LED  102  to indicate when an exposure by the imaging system  12  is occurring. The LED  102  of the device  40  illuminates during the exposure. An LED  101  could indicate an inhibit on the imaging system  12  that currently prevents exposure initiation. An LED  103  could indicate that wireless communication is occurring. A combination of the LEDs could indicate that the wireless handheld interface device  40  is in the process of or has completed association or pairing with imaging system  12 . Alternative embodiments may include additional LEDS to provide an indication of system operation data. The handheld interface device  40  also includes a speaker  104 . The speaker  104  can provide an audible tone or tone sequence during the occurrence of the exposure. Also, the speaker  104  may provide an audible tone for a locator signal as described below. 
       FIG. 5  illustrates the handheld interface device  42  of  FIGS. 1 and 2  that includes similar and additional features. The handheld interface device  42  may be based upon or include a personal digital assistant, a multipurpose cellular telephone, or other handheld device. The handheld interface device  42  includes an exterior housing  90  that is suitably dimensioned to fit in the hand of the user. The handheld interface device  42  is configured to be paired with the single X-ray system  10  and to provide user detectable indications of the operational status of the imaging system  12 . In addition, the handheld interface device  42  is configured to receive a user-input command for operation of the imaging system  12 , as well as patient data and/or instructions. Further, the handheld interface device  42  is configured to have the location and/or movement of the device  42  tracked by the imaging system  12  to be used by the system  12  as an input for one or more control functions of the system  12 . The handheld interface device  42  includes screen  46  and a combination of buttons and LEDs to interact with the imaging system  12 . The screen  46  is configured display system operational data and X-ray system or exposure settings. For example, the screen  46  may display the exposure parameters such as a kilovolt peak setting  106 , a milliamp setting  108 , or other settings such as a milliamp-second setting. The screen  46  may include one or more icons  110  that represent system operational data. For example, the icons  110  may represent the charge status of the power supply  78  to the X-ray source  16  and/or mobile drive unit  82 , power status of the device  42 , readiness of X-ray system  10  for exposure, inhibition of the X-ray source  16 , an exposure in progress, a wireless link connection, and other operational data. The screen  46  is also configured to display patient data, instructions, and images. The handheld interface device  42  may also include LEDS to indicate system operational data as described with device  40 . For example, LED  112  may illuminate when an exposure is in progress. 
     Additionally, the handheld interface device  42  may include buttons  114  and  116 , which may be actual depressible switches, regions of a touch screen, or any other suitable user interface. The buttons  114  and  116  may be used to input commands for the imaging system  12  to execute. These commands may be used for multiple functions when pressed, including preparing and initiating an exposure by the system  12 , operating the collimator light  66 , inputting the location of the device  42  with respect to the system  12  (e.g., to calculate a source-to-image distance), and other functions. The buttons  114  and  116  when used as a prepare/expose button may not be pressed when operation of the X-ray source  16  is inhibited. 
     In addition, the screen  46  of the handheld interface device  42  may include a touch-screen to allow the user to interface with the system  12  and to input commands for the operation of the system  12 . The screen  46  may allow the user to select from a variety of modes to operate the imaging system  12 . For example, the screen  46  may include exposure parameters  106  and  108 , described above, as well as arrows  118  to change the settings of the exposure parameters  106  and  108 . Instead of the buttons  114  and  116 , the screen  46  may be used to prepare for and initiate the system  12  for an exposure. Further, the handheld interface device  42  includes a speaker/recorder  120 . The speaker  120  provides an audible tone during exposures. Also, the speaker  104  may provide an audible tone for a locator signal as described below. Further, the speaker  104  may serve as a microphone, or a separate microphone (not shown) may be provided and the device configured to act as a recorder to allow the user to dictate voice inputs. The voice inputs may then be recorded by the device  42  and/or in the X-ray system  10 , the HIS, RIS or PACS and associated with an X-ray imaging sequence. 
       FIG. 6  illustrates a diagrammatical overview of the handheld interface device  40 . The handheld interface device  40  includes a control circuitry  122  to control the various functions of the device  40  and a wireless interface  124  to communicate with the imaging system  12 . The wireless interface  124  may utilize any suitable wireless communication protocol, such as an IEEE 802.15.4 protocol, an ultra wideband (UWB) communication standard, a Bluetooth communication standard, or any IEEE 802.11 communication standard. The control circuitry  122  includes a processor  126  to process the various signals received via the wireless interface  124  from the system  12 . In addition, the processor  126  receives input signals from input devices and generates command signals to be transmitted to the system  12  via the wireless interface  124 . The control circuitry  122  also includes a memory  128  for storing programs and routines executed by the processor  126 , as well as configuration parameters of the handheld interface device  40 . The processor  126  and memory  128  are connected to interface circuitry  130  that interacts with the input and output devices of the handheld interface device  40  to receive input signals from the input devices and to transmit output signals to the output devices and/or wireless interface  124 . 
     The control circuitry  122  is powered and in communication with a power supply  132 . The power supply  132  may be a rechargeable battery (e.g., a thin film battery). The power supply  132  includes a charging interface  134  configured for charging of the power supply  132  when the handheld interface device  40  is located in a charger (e.g., the cradle  64  of the X-ray base station  50 ). The charge cradle  64  can charge the power supply  132  of the handheld interface device  40  either through conductive charge contacts or through inductive or capacitive contactless charging methods. Alternatively, the power supply  132  may include photovoltaic cells to recharge the handheld interface device  40 . Further, the power supply  132  may include a device to harvest radiofrequency energy or piezoelectric energy (e.g., microelectricalmechanical system (MEMS) device). 
     The interface circuitry  130  receives system operational data from the system  12  via the wireless interface  124  and transmits the data to the processor  126 . Once the data is processed a signal is generated by the processor  126  and transmitted via the interface circuitry  130  to the output devices. For example, the handheld interface device  40  may receive a command from imaging system  12  to locate the device  40 . The speaker  104  may generate a locator signal in response to the command. The speaker  104  may also generate a user audible tone when an exposure is taking place. The speaker  104  may generate an audible tone if the handheld device  40  is out of the charge cradle  64  for a minimum time. Also, various LEDS  136  may be illuminated to provide the user an indication of the system operational status as described above. Further, besides a visual and audible indication of an exposure, the handheld interface device  40  includes a vibrating motor  138  to vibrate and provide a tactile indication of the occurrence of an exposure in progress. 
     The handheld interface device  40  also provides commands to the imaging system  12 . For example, as described above, the device  40  may include a collimator light button  96  to activate and deactivate the collimator light  66 , and the prepare/expose button  92  to prepare and initiate exposures with the system  12 . Input signals received from these buttons  140 ,  92 , and  96  generate command signals wirelessly transmitted to the system  12  for execution. The handheld interface device  40  may include other devices  142  besides the input and output devices described for operation of the device  40 . For example, other devices  142  may include a tracking device, as described below, or a flash light. 
       FIG. 7  illustrates a diagrammatical overview of the handheld interface device  42 . The handheld interface device  42  includes control circuitry  122 , power supply  132 , and wireless interface  124  similar to the embodiment in  FIG. 6 . However, the memory  128  is also capable of storing images transmitted from the imaging system  12  (in digital X-ray systems  10 ), patient data/and or instructions received from the system  12  or network  48 , system operational data (e.g., dose area product to be embedded in image sequences), and user input (e.g., audible recordings to be associated with an imaging sequence). As described above, the handheld interface device  42  includes one or more LEDS  136  to provide user detectable indications of the system operational data of the imaging system  12 . 
     The handheld interface device  42  also includes the screen  46  to display system operational data, such as in the form of icons  110  as shown in  FIG. 5 . The system operational data may also be displayed in other forms on the screen  46  (e.g., textual or numerical form). For example, exposure parameter settings  106  and  108  may be presented on the screen  46 . The screen  46  may also include a touch-screen  46  capable of encoding inputs by touch. For example, a gesture on the touch-screen  46  (e.g., pressing an arrow displayed on the touch-screen  46  in  FIG. 5 ) may be user input. In some embodiments, the gesture may be interpreted as a multi-point gesture. Images of the patient  20  received via the camera  24  or network  48  may also be displayed on the screen  46 . Alternatively, a still image of the patient  20  or a generic image of an anatomical region of the patient  20  may also be displayed on the screen  46 . The user may be able to input a location on the anatomy of the patient  20  to be imaged by touching the portion of the anatomy on the touch-screen  46 , as described below. 
     Also, as described above, the device  42  may include a speaker/recorder  120 . The speaker  120  allows for the output of an audible tone or tone sequence during an exposure. In addition, the speaker  120  may output a locator signal in response to a command from the imaging system  12  to locate the device  42 . The speaker  120  also allows the recording of user-dictated voice inputs that may be recorded and stored in the memory  128  for association with an X-ray image sequence. Also, the user-dictated voice input may be transmitted via the wireless interface  124  to the imaging system  12  to be emitted for the hearing of the patient  20  undergoing X-ray imaging. 
     As mentioned above, the handheld interface device  42  may include buttons  114  and  116  to allow the user to make various inputs. For example, the buttons  114  and  116  may be used to prepare and initiate an exposure or operate the collimator light  66 . Alternatively, these functions, as well as others, may be carried out using inputs via the touch-screen  46 . The buttons  114  and  116  may be used in conjunction with other devices of the handheld interface device  142 . For example, the device may include a tracking device  144 . The tracking device  144  may comprise various inertial measurement units such as an accelerometer, a magnetometer, an inclinometer, and/or a gyroscope. These inertial measurement units allow the relative position and rotation of the device  42  to be tracked in a 3-D coordinate system. The imaging system  12  is configured to track the location and/or movement of the device  42  as received from the tracking device  144  via the wireless interface  124 . The location and/or movement of the device  42  are used as input to control functions of the system  12 . The tracking device  144  may be used with another input device (e.g., the buttons  114  and  116  or touch-screen  46 ) to record one or more locations of the device  42  to allow the system  12  to calculate various system operational parameters or to setup the desired imaging sequence. Further, the tracking device  144  may be used by the imaging system  12  to monitor the presence of the handheld interface device  42  within the operative range of system  12 . If the handheld interface device  42  is moved outside the operative range of the system  12 , the system  12  may send a command to the device  42  to generate an audible tone via the speaker  120 . 
     Similar to device  40 , the handheld interface device  42  may include other devices  142  besides the input and output devices described above for operation of the device  42 . All of these devices may be used separately or in combination to receive input commands for the operation of the imaging system  12  and to transmit these commands to the system  12  for execution. 
     As mentioned above, the handheld interface device  38  is configured to receive system operational data wirelessly communicated from the imaging system  12  and to provide a user detectable indication of the imaging system operational status based on the data.  FIG. 8  illustrates an exemplary type of system operational data  146  received by the handheld interface device  38  by the imaging system  12 . The types of system operational data  146  illustrated are only examples and other types of system operational data  146  may be presented. The system operational data  146  includes a locator signal  148  when the handheld interface device  38  cannot be found by the user. Other system operational data  146  includes X-ray source settings  150 . These may include a kilovolt peak setting, a milliamp setting, and a milliamp-second setting. The system operational data  146  includes a dose area product  152 . The dose area product  152  reflects the dosage of radiation, as well as the volume of tissue irradiated, with each image sequence. Also, an execution of a current exposure  154  is included. The system  12  ceases transmitting this particular system operational data  146  when the exposure execution  154  concludes. When operation of the X-ray source  16  is inhibited, the device  38  receives an X-ray source inhibit  156 , as described above. Further, the system operational data  146  includes a system charge status  158  for the power supply  78  of the imaging system  12  that powers the X-ray source  16  and the mobile drive unit  82  (in mobile systems). 
     Besides receiving system operational data  146 , the handheld interface device  38  may also be configured to receive user-input commands for operation of the imaging system  12 .  FIG. 9  illustrates various user-input and/or user-input commands  160  received by the handheld interface device  38  and wirelessly transmitted to the imaging system  12 . As previously mentioned, the user-input commands  160  include X-ray source settings  150 . The command for X-ray source settings  150  may include settings for exposure parameters of the X-ray source  16 , such as the kilovolt peak setting, the milliamp setting, the milliamp-second setting, a focal spot selection, source-to-image distance, source-to-patient distance, and orthogonality. Also, user-input commands  160  include movement of the X-ray source  16 . This movement may include the movement of a remotely movable X-ray source  16  to a desired position via either the movement of the overhead tube support arm  14  in fixed system  12  or the movement of the support arm  52  and/or support column  54  in a mobile system  12 . The user-input commands  160  also include a movement command  164  for fine movement of the mobile system  12  via the wheeled base  58 . As previously mentioned, the user-input commands  160  include a collimator light command  166  to illuminate the collimator light  66  on the region of the patient  20  that will receive X-ray radiation during an imaging sequence. 
     Also, patient audible commands  168  may include a signal from the device  38  to the imaging system  12  to transmit the patient-audible command  168  in response to the signal. These signals may correspond to multiple pre-recorded patient audible commands  168  stored within the control circuitry  74  of the system  12 . Moreover, the patient-audible commands  168  may be pre-recorded in at least two spoken languages. The patient-audible commands  168  may be transmitted via the system speaker  44 . A user, then, who does not speak a particular language may nevertheless issue instructions to the patient in the patient&#39;s language simply by selecting the desired instructional message via the handheld device. Also, as mentioned above, certain embodiments of the handheld interface device  38  (e.g.,  42 ) may be configured to receive, to record, and/or transmit user-dictated voice inputs  170 . The transmitted user-dictated voice inputs  170  may be received by the imaging system  12  and emitted for the patient  20  undergoing X-ray imaging to hear. 
       FIGS. 10-17  that follow illustrate various scenarios for the use of the handheld interface device  38  and/or interaction with the imaging system  12 .  FIG. 10  illustrates a scenario where the handheld interface device  38  and the imaging system  12  are outside a desired range. The imaging system  12  illustrated is mobile, but the system  12  may also be fixed. The imaging system  12  and/or the handheld interface device  38  are configured to determine the strength of the wireless signals between each other. A preset desired wireless strength that corresponds to a specific distance between the device  38  and the system  12  may be set. This preset desired wireless strength may vary depending upon the setup of the X-ray system  10 . As the user  36  moves away from the system  12  with the device  38  the wireless strength decreases. If the wireless strength falls below the preset desired wireless strength, then the imaging system  12  and/or the handheld interface device  38  are configured to emit a user-perceptible signal (e.g., audible tone via speakers  44 ,  104 , and/or  120 ) to indicate that the system  12  and the device  38  are greater than a desired distance apart. 
     As mentioned above, certain embodiments of the handheld interface device  38  (e.g.,  42 ) may include tracking devices  144  or the device may be configured to perform tracking based on signal strength, or a similar parameter.  FIG. 11  illustrates a scenario where the tracking device  144  allows the imaging system  12  to follow the handheld interface device  38 . The imaging system  12  illustrated is a mobile system. The imaging system  12  is configured to track the location and/or movement of the handheld interface device via the tracking device  144  located within device  38 . The user  36  may input a command via one of the input devices available on the handheld interface device  38  (e.g., screen  46 ) for the system  12  to follow the device  38 . As the user  36  moves throughout a building, the system  12  tracks the location of the handheld interface device  38  via the tracking device  144  and follows the device  38  as it is displaced. This may dispense with the need for the system to be guided, pushed or driven for at least some of its movement through an institution. 
     Another use for the tracking device  144  of the handheld interface device  38  is shown in  FIG. 12 .  FIG. 12  illustrates the imaging system  12  with the patient  20  located on the table  26  between the X-ray source  16  and the image receptor  22 . The imaging system  12  may be a fixed or mobile system. The X-ray source  16  may be moved to a desired position via either the movement of the overhead tube support arm  14  in the fixed system  12  or the movement of the support arm  52  and/or support column  54  in the mobile system  12 . As above, the user may input a command via one of the input devices available on the handheld interface device  38  (e.g., screen  46 ) for the system  12  to move the X-ray source  16  based upon the location and/or movement of the handheld interface device  38  to the desired position. As the handheld interface device  38  is moved within a 3-D coordinate system along an x, y, and z axes, the X-ray source  16  is correspondingly moved along the same axes to the desired position. 
     The tracking device  144  can also similarly be used to provide an input to the imaging system  12  to perform a desired X-ray image data acquisition sequence.  FIG. 13  illustrates the use of the handheld interface device  38  to perform a desired imaging sequence. The illustrated imaging system  12  is as described in  FIG. 12 . The user  36  may select an image acquisition sequence mode via one of the input devices available on the handheld interface device  38  (e.g., screen  46 ). Once in the acquisition mode, the imaging system  12  is configured to record one or more locations of the handheld interface device  38  via the tracking device  144  and to use the recorded locations as input for an X-ray imaging sequence. The recorded locations may be used as inputs for determining a tomographic sweep by the X-ray source  16 . For example, using the input devices on the handheld interface device  38 , a first location, A, may be selected and then recorded by the system  12 . Then, similarly the device  38  may be used to select a second location, B, to be recorded by the system  12 . Upon initiation of the X-ray imaging sequence, the radiation source  16  moves between locations A and B performing the desired imaging sequence (e.g., tomographic sweep) generating multiple images  172  between those locations. 
       FIG. 14  illustrates the use of the handheld interface device  38  to compute various exposure parameters. The imaging system  12  illustrated is as described in  FIG. 12 . The handheld interface device  38  and the tracking device  144  may be used to input the location of the device  38  as described above. The imaging system  12  is configured to use the location of the device  38  for the computation of various exposure parameters, such as source-to-image distance (SID)  174 , source-to patient distance  176 , and patient thickness  178 . The SID  176  is determined by placing the handheld interface device  38  at the image receptor  22  and inputting the location of the device  38  (location A). The system  12  uses location A with respect to the X-ray source  16  in the computation of SID  176 . The source-to-patient distance  176  is similarly determined by placing the handheld interface device  38  on the patient  20  where the exposure is to take place and inputting the location of the device  38  (location B). The imaging system  12  then takes the difference between the source-to patient distance  176  and the SID  174  for the computation of the patient thickness  178 . The patient thickness  178  may be used by the imaging system  12  to set an X-ray dose parameter for the exposure. 
       FIG. 15  illustrates a further use of the handheld interface device  38 . The imaging system  12  is illustrated with the patient  20  located on an inclined surface  180  (e.g., bed  60 ) between the X-ray source  16  and the image receptor  22 . The image receptor  22  may have a grid  182  located on the image receptor  22  to reduce the scattering of the X-rays. The imaging system  12  may be a fixed or mobile system. The X-ray source  16  may be moved to a desired position via either the movement of the overhead tube support arm  14  in the fixed system  12  or the movement of the support arm  52  and/or support column  54  in a mobile system  12 . As above, the user places the handheld interface device  38  on the image receptor  22  and/or grid  182  and inputs a command via one of the input devices to transmit the location of the device  38  as derived from the tracking device  144  and thus the relative location of the image receptor  22  and/or grid  182  to the system  12 . The inputted location of the handheld interface device  38  is used to compute the orthogonality between the image receptor  22  and/or grid  182  with respect to the X-ray source  16 . The calculated orthonogonality is displayed on the screen  46  of the handheld interface device  38 . Based on the calculated orthogonality the imaging system  12  also may move the X-ray source  16  along a desired x, y, and z axes. For example, the X-ray source may be initially positioned in a first position, A. After determining the orthogonality between the X-ray source  16  and image receptor  22  and/or grid  182 , the system  12  may move the X-ray source  16  to a second position, B, with the desired orthogonality. 
     The handheld interface device  38  has additional features. In embodiments of the handheld interface device  38  with a screen  46  (e.g.,  42 ), the screen  46  is configured to display patient data  184  as illustrated in  FIG. 16 . Types of patient data  184  include an identifying image  186  of the patient  20 . The identifying image  186  may be provided via the network  48  or the imaging system  12 . The system  12  may also provide an image  188  of the patient  20  or a portion of the anatomy of the patient  20  to receive X-ray radiation via the system camera  24 . The image  188  may be a still or live image. Also, the image  188  may be a generic image representative of an anatomical region of the patient  20 . Additional patient data  184  displayed by the screen includes patient identifying data  190  such as the name of the patient, the anatomy to be imaged, the types of images, and further instructions or information. The screen  46  also displays reconstructed X-ray images  192  of the patient  20  received from the system  12  (in digital X-ray systems  10 ). 
       FIG. 17  illustrates the use of the screen  46  to control the movement of the X-ray source  16 . The illustrated imaging system  12  is as described above. The user receives the image  188  of the patient  20  on the screen  46  of the handheld interface device  46 . The screen  46  illustrated is touch-screen  46  capable of encoding inputs by the touch of the user. The user uses a finger or other object  194  to input a selection  196  of a specific part of the patient anatomy for exposure. The device  38  transmits a signal to the imaging system  12  specifying the desired anatomy for exposure to X-ray radiation. The imaging system  12  is configured to move the X-ray source  16  into position to take the desired exposure. Then, the system  12  (in a digital X-ray system  10 ) is configured to process X-ray image data and to generate the reconstructed image  192  of the desired anatomy. The screen  46  of the handheld interface device  38  displays the reconstructed image  192  of the desired anatomy. 
       FIGS. 18-21  illustrate various methods for operation of the handheld interface device  38 .  FIG. 18  illustrates a flow diagram of a method  198  for operating the handheld interface device  38 . The method  198  includes establishing wireless communication between the imaging system  12  and the handheld interface device  38  (block  200 ). The system  12  includes the components described above in  FIG. 3 . The imaging system  12  and the handheld interface device  38  communicate via their respective wireless interfaces  76  and  124 . Following the establishment of a wireless link, system  12  communicates system operational data  146  to the handheld interface device  38  (block  202 ). The handheld interface device  38  then provides a user detectable indication of the operational status of the imaging system  12  based upon the received data  146  (block  204 ). The user detectable indication includes vibration of the device  38 , illumination from LEDS, among other indications. 
       FIG. 19  illustrates another flow diagram of a method  206  for operating the handheld interface device  38 . The method  206  includes establishing wireless communication between the system  12  and device  38  (block  208 ) as described in method  198 . After establishing a wireless link, the user inputs a command into the handheld interface device  38  for operation of the imaging system  12  (block  210 ). The user-input command  160  may include the movement of the X-ray source  16  or the fine movement of the system  12 , if mobile, as an example. Following input of the command, the handheld interface device  38  wirelessly transmits the command to the system (block  212 ), whereupon the imaging system  12  is configured to receive and execute the command for operation of the system  12 . 
       FIG. 20  illustrates a flow diagram of a method  214  for viewing patient data on a handheld interface device  38 . The method  214  includes establishing wireless communication between the system  12  and device  38  (block  216 ) as described in method  198 . The handheld interface device  38  includes user-viewable screen  46  configured to display patient data  184  and to receive a user input (e.g., touch-screen  46 ). After establishing a wireless link, the handheld interface device receives patient data  184  either from the imaging system  12  or the HIS  88  or RIS  86  of the medical facility&#39;s network  48  (block  218 ). The imaging  12  may also transmit the image  188  of the patient  20  or anatomical region of the patient  20  to the device  38  (block  220 ) via the system camera  24 . Alternatively, the image  188  (e.g., generic image representative of anatomical region of patient  20 ) may be provided by the network  48 . After receiving the patient data  184 , the data  184  is displayed on the screen  46  (block  222 ). If the patient data consists of the image  188  of the patient  20 , the user may select a desired portion of the anatomy for exposure (block  224 ). The selection  196  may be transmitted as a signal to the system  12  (block  226 ) for that region to be imaged. In response to the signal, the X-ray source  16  may need to be moved to make the desired exposure. The system  12  (in a digital X-ray system  10 ) may then acquire and process X-ray image data of the selected anatomy (block  228 ). Then, the system  12  may generate a reconstructed X-ray image  192  (block  230 ). This reconstructed X-ray image  192  may be transmitted to and displayed on the screen  46  of the handheld interface device  38  (block  232 ). 
       FIG. 21  illustrates a flow diagram of a method  234  for tracking the location of the handheld interface device  38 . The method  234  includes establishing wireless communication between the system  12  and device  38  (block  236 ) as described in method  198 . The handheld interface device  38  includes tracking device  144  which is configured to provide a location and to track movement of the handheld interface device. After establishing a wireless link, the tracked location and/or movement of the handheld interface device  38  is transmitted to the imaging system  12  (block  238 ). The imaging system  12  then uses the tracked location and/or position as input to control at least one function of the system  12  (block  240 ). For example, the input may be used to direct the system  12 , if mobile, to follow the handheld interface device  38 . 
     The handheld interface device  38  described above provides the user increased information about the imaging system  12  while allowing the user to work at a distance from the system  12  and providing a safer environment. The wireless design alleviates the problems typically associated with a cord, such as interference with medical equipment or damage to the cord over time. Additionally, the user may find the device  38  if ever lost via a locator signal. Further, the device  38  provides the user three different types of feedback mechanisms to indicate a current exposure including visual, audible, and tactile (vibrations). 
     The more advanced features of the handheld interface device  38  provide the user more flexibility in controlling the system  12 , particularly in light of advanced user control features provided by the touch-screen  46  and the tracking device  144 . For example, the advanced features would assist in allowing the user to better position the system  12  and image receptor  22 , particularly when the patient  20  is in a complicated position, for acquiring an improved image. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.