Patent Publication Number: US-11656346-B2

Title: Ultrasound imaging system including wireless probe tracking

Description:
The present application is a continuation of U.S. patent application Ser. No. 17/071,813, entitled “ULTRASOUND IMAGING SYSTEM INCLUDING WIRELESS PROBE TRACKING”, filed on Oct. 15, 2020, which is a continuation of U.S. application Ser. No. 16/011,400, entitled “ULTRASOUND IMAGING SYSTEM INCLUDING WIRELESS PROBE TRACKING”, filed on Jun. 18, 2018, now issued as U.S. Pat. No. 10,838,050, and which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present technology relates to ultrasound imaging systems, and in particular to systems including transducer probes having wireless tags for improving workflow within clinical settings. 
     BACKGROUND 
     In ultrasound imaging, an operator of an ultrasound system uses a probe to obtain data for ultrasound images of a patient during an imaging procedure. Multiple probes may be compatible with the same system, and a particular probe or probes may be more suitable for a certain imaging procedure than other probes. Often, the operator is unaware that a more suitable probe for the imaging procedure is nearby (e.g., in the same room as the ultrasound system). Alternatively, the operator may be aware of nearby probes that are available for use during the imaging procedure, but unaware that a certain probe is more suitable for the procedure than a probe they have selected for use during the imaging procedure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a simplified illustration of an ultrasound imaging system configured in accordance with an embodiment of the present technology. 
         FIG.  2    is a schematic diagram of various electronic components of the ultrasound imaging system shown in  FIG.  1    configured in accordance with an embodiment of the present technology. 
         FIG.  3    is a flow diagram of a method or process of locating or selecting a nearby transducer device for an ultrasound imaging procedure in accordance with an embodiment of the present technology. 
     
    
    
     DETAILED DESCRIPTION 
     Specific details of several embodiments of ultrasound systems having wireless communication between a base unit and one or more probes are described below. In some embodiments, for example, an ultrasound imaging system includes a plurality of transducer devices each having a wireless tag storing data about the transducer device. The ultrasound system further includes a base unit including a display, a memory storing instructions, and a processor or logic circuitry. The processor or logic circuitry can be configured to receive data from one or more of the wireless tags about nearby transducer devices located proximate to the base unit. The processor or logic circuitry can further be configured to produce a graphic on the display or other cue alerting a user of the device(s) that are located proximate to the base unit. In some embodiments, the graphic is a list that the operator may sort or filter based on the data from the wireless tags in order to identify a particular one of the nearby transducer devices that has a desired attribute. 
     Certain details are set forth in the following description and in  FIGS.  1 - 3    to provide a thorough understanding of various embodiments of the present technology. In other instances, well-known components, devices, structures, materials, operations, and/or systems often associated with ultrasound imaging systems are not shown or described in detail in the following disclosure to avoid unnecessarily obscuring the description of the various embodiments of the present technology. Those of ordinary skill in the art will recognize, however, that the present technology can be practiced without one or more of the details set forth herein, or with other structures, methods, components, and so forth. The phrases “in some embodiments,” “according to some embodiments,” “in certain embodiments,” “in the illustrated embodiment,” “in other embodiments,” and the like generally mean the particular feature, structure, or characteristic following the phrase is included in at least one implementation of the present technology, and may be included in more than one implementation. In addition, such phrases do not necessarily refer to the same embodiments or different embodiments. 
     The terminology used below is to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain examples of embodiments of the technology. Indeed, certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section. 
     I. SELECTED EMBODIMENTS OF ULTRASOUND SYSTEMS HAVING WIRELESS TAGS 
       FIG.  1    is a partial schematic illustration of an ultrasound imaging system  100  (“system  100 ”) for imaging a region of interest of a subject or patient  1 . In the illustrated embodiment, the system  100  includes an ultrasound transducer device or probe  110   a  (“probe  110   a ”) operably coupled to a base unit  120  by a signal cable  130   a . The probe  110   a  includes a housing  112  (e.g., a molded plastic housing) having a scan head region  114  that encloses a single movable transducer element or an array of transducer elements. In some embodiments, the probe  110   a  can include one or more buttons, triggers, touch sensors, or other input devices (not shown) configured, for example, to toggle power on or off, to put the system  100  in a run/standby state, or to perform other operations. The base unit  120  can be a hand-held, portable, or cart-based unit including a display  122  (e.g., a touchscreen display), one or more operator controls  124 , and input/output ports (I/O)  126 . The operator controls  124  can include, for example, buttons, knobs, switches, a keyboard, a touchscreen, etc. The I/O ports  126  can include, for example, audio, universal serial bus (USB), high-definition multimedia interface (HDMI) ports), EKG ports, etc. 
     During an ultrasound imaging procedure, an operator (e.g., a physician, sonographer, ultrasound technician, etc.) can use the probe  110   a  and the base unit  120  to perform an ultrasound scan. In particular, the operator can direct the probe  110   a  toward the region of interest (e.g., an organ, a vessel, an internal cavity, etc.) of the patient  1  and use the probe  110   a  to transmit ultrasound signals into the region of interest and to receive the corresponding echo signals. The system  100  converts one or more characteristics of the received echo signals (e.g. their amplitude, phase, power, frequency shift, etc.) into image data that is formatted and displayed for the operator as an image on the display  122 . In some embodiments, the operator can use the operator controls  124  to input information about the particular region of interest, characteristics of the patient  1 , or other information relevant to the imaging procedure into the system  100 . 
     In some embodiments, the system  100  can include more than one probe that is compatible with the base unit  120  and that can be operably connected to the base unit  120  for performing an ultrasound scan. For example, in addition to the probe  110   a , the system can include a plurality of probes  110   b - 110   n  (collectively “probes  110 ”). Each of the probes  110  can have generally similar features or components (e.g., a housing enclosing one or more transducer elements configured to transmit ultrasound signals), but can have different form factors, operating frequencies, focal depths, and/or other characteristics that are optimized for different imaging functions. Accordingly, as described in detail below, depending on the particular imaging procedure to be carried out on the patient  1 , a particular one or ones of the probes  110  may be more appropriate (e.g., better suited, customized, adapted, etc.) for the imaging procedure than the others. In the illustrated embodiment, each of the probes  110  includes a corresponding signal cable  130  (labeled individually as signal cables  130   b - 130   n ) for operably coupling the probes  110  to the base unit  120 . In other embodiments, the probes  110  can be configured for wireless communication and operation with the base unit  120 . In some embodiments, the base unit  120  can be operably connected to more than one of the probes  110  at the same time. 
     As further illustrated in  FIG.  1   , each of the probes  110  includes a wireless tag  115  (labeled individually as wireless tags  115   a - 115   n ). In some embodiments, the wireless tags  115  are active or passive radio-frequency identification (RFID) tags such as, for example, Bluetooth Low Energy (BLE) tags. As described in detail below with reference to  FIG.  2   , the base unit  120  is configured for wireless communication with the wireless tags  115  to, for example, determine that some or all of the probes  110  are located proximate to the base unit  120  and/or to receive supplemental data (e.g., supplemental information) about the probes  110 . In the illustrated embodiment, the wireless tags  115  are shown affixed to the exterior of the housing of the probes  110 . In other embodiments, the wireless tags  115  can be integrated with or embedded within the probes  110 , or the signal cables  130  that connect the probes  110  to the base unit  120 . 
       FIG.  2    is a schematic diagram of various electronic components of the system  100  shown in  FIG.  1    configured in accordance with an embodiment of the present technology. In the illustrated embodiment, the system  100  includes transducer electronics  240  at each of the probes  110 , base unit electronics  250  at the base unit  120 , and wireless tag electronics  260  at each of the wireless tags  115 . In the following description, reference is made to the probe  110   a  and wireless tag  115   a  shown in  FIG.  1    for the sake of clarity. 
     The transducer electronics  240  can drive a transducer array  241 , such as an array of piezoelectric transducer elements, located at the scan head region  114  of the probe  110   a . The transducer electronics  240  can also include one or more driver circuits  242  configured to supply driving voltage to the piezoelectric transducer elements in such a fashion that an ultrasound beam is produced in a desired direction. The transducer electronics  240  can also include, for example, waveform generators  243 , amplifiers  244 , analog-to-digital converters (ADCs)  245 , and other ultrasound signal processing components (e.g., a CPU, controller, transmit/receive beam forming circuitry, etc.). In some embodiments, at least a portion of the transducer electronics  240  can be located at the base unit  120 . In some embodiments, for example where the probe  110   a  is configured for wireless operation with the base unit  120  without the signal cable  130   a , the transducer electronics  240  can further include a power source  249  (e.g., a battery). 
     The base unit electronics  250  include a central-processing unit (“CPU”)  251 , input/out devices (I/O) devices  254 , communication components  257 , and a power source  259 . The CPU  251  includes a programmable processor (microprocessor, GPU, DSP or equivalent logic circuits, or a combination thereof)  253  configured to execute instructions stored in a memory  252  or operate as configured in order to perform various processes, logic flows, and routines. The I/O devices  254  can include, for example, the display  122 , the operator controls  124 , one or more microphones  255 , one or more speakers  256 , USB ports, EKG ports, HDMI ports, and/or other suitable components. The communication components  257  can include, for example, signal buses coupled to the I/O ports  126 , a suitable network adaptor, a wireless transceiver (e.g., Bluetooth, Wi-Fi or cellular transceiver), or other suitable components for communication over computer communication links (LAN, WAN, Internet etc.) through a wired (e.g., Ethernet, USB, Thunderbolt, Firewire, or the like) or wireless (e.g., 802.11, cellular, satellite, Bluetooth, or the like) communication link. As further illustrated in  FIG.  2   , the communication components  257  include one or more wireless antennas  258  for receiving/transmitting wireless signals from/to the wireless tags  115  in one or more of the probes  110 . In a particular embodiment, the wireless antennas  258  are configured for communication with the wireless tags  115  via a Bluetooth connection. 
     In the illustrated embodiment, the wireless tag electronics  260  are not powered by the same power source that powers (e.g., are separate from) the transducer electronics  240 . Accordingly, the wireless tag  115   a  can include a separate power source  262 . In some embodiments, the power source  262  is a CR2032 lithium coin battery or other suitable battery. In other embodiments, the wireless tag electronics  260  can be at least partially coupled to or integrated with the transducer electronics  240  (e.g., sharing a common power source). As shown, the wireless tag electronics  260  further include a memory  264 , and a transceiver  266  configured for wireless communication with the base unit electronics  250  via a BLE or other suitable connection. In some embodiments, the wireless tag electronics  260  further include a speaker  268  or other output device, and/or a GPS receiver or other location detection receiver. 
     The memory  264  can be a read-only non-volatile memory storing supplemental data about the probe  110   a . For example, the data stored in the memory  264  can include information about invariable or semi-invariable properties or attributes of the probe  110   a , such as its physical, operational, or functional characteristics (e.g., a center frequency, a shape (e.g., curved or linear), etc.), procedures generally performed with the probe (e.g., cardiac, abdominal, musculoskeletal, etc.), a type of patient the probe is generally used with (e.g., adult, pediatric, infant, etc.), serial numbers, warranty information, ownership information, usage information, etc. In some embodiments, the memory  264  can be a programmable memory (e.g., an electrically erasable programmable read-only memory (EEPROM)) that can be erased and reprogrammed to store data about varying attributes or properties of the probe  110   a . For example, the data stored in the memory  264  can include information about: a cleaning history of the probe  110   a  (e.g., information about the last use and/or cleaning of the probe  110   a ); maintenance history or a maintenance schedule of the probe  110   a  (e.g., information about a date and/or time when the last current leakage or other integrity test was performed on the probe  110   a , a date and/or time of the next scheduled integrity test for the probe  110   a , a power level of the power source  262  of the wireless tag electronics  260 , a date/time when the power source  249  and/or the power source  262  were last replaced, etc.); historical usage of the probe  110   a  (e.g., information about when the probe  110   a  was last used, the user and/or usage time, non-identifying patient data such as the number and type of patients on which the probe  110   a  was used, ultrasound procedures the probe  110   a  was previously used for, whether there were transducer element failures with the probe  110   a  during a previous use, etc.); an assigned location or storage site of the probe  110   a  (e.g., information that the probe  110   a  is normally stored in a particular drawer, cabinet, etc., within a particular examination room); an actual or average location of the probe  110   a  based on one or more detected GPS or Wi-Fi signals; a preferred status of the probe  110   a  (e.g., that the probe  110   a  is preferred by a certain operator, for a particular imaging procedure, etc.); and/or other properties or attributes of the probe  110   a  that may be relevant to an operator of the system  100 . 
     In operation, the wireless tag  115   a  can be configured to continuously, nearly-continuously, or intermittently transmit a wireless signal (e.g., a Bluetooth or BLE signal). The base unit electronics  250  are configured to determine that the probe  110   a  is located proximate to (e.g., located nearby to, within a predetermined range of, etc.) the base unit  120  by detecting a wireless signal from the wireless tag  115   a . As described in detail below, the CPU  251  can further process the signal from the wireless tag  115   a  and cause one or more of the I/O devices  254  to indicate that the probe  110   a  is located nearby to the base unit  120 . For example, the CPU  251  can cause the display  122  to display an indication, a graphic, a map, etc., showing that the probe  110   a  is located proximate to the base unit  120  and further showing any of the supplemental data associated with the probe  110   a.    
     In some embodiments, where the memory  264  is a programmable memory, the CPU  251  can operate to generate and send one or more update signals to the wireless tag  115   a  for updating the data stored in the memory  264 . For example, the base unit electronics  250  can update the data stored in the memory  264  to reflect the latest cleaning, maintenance, use, storage location, etc., of the probe  110   a . More particularly, the operator of the system  100  can use the I/O devices  254  to input the updated information into the base unit electronics  250  for transmission to the wireless tag electronics  260 . In some embodiments, the base unit electronics  250  can be programmed or configured to automatically update any of the data stored by the wireless tag  115   a —for example, during or after an imaging procedure is performed with the probe  110   a , after maintenance is performed on the probe  110   a , etc. 
     II. SELECTED EMBODIMENTS OF METHODS FOR DETECTING PROXIMATE TRANSDUCER PROBES 
     With reference to  FIGS.  1  and  2   , and as set forth above, the system  100  is configured to detect that one or more of the probes  110  are located proximate to the base unit  120  by detecting signals transmitted by the wireless tags  115 . That is, signals from wireless tags  115  of probes  110  that are within range of the base unit  120  (e.g., in the same room in a medical facility as the base unit  120 ) will be detected and those probes  110  will be determined to be proximate to the base unit  120 , while probes  110  that are out of range of the base unit  120  (e.g., in a different room in the medical facility) will not be detected by the base unit  120 . The detection of proximate probes  110  may be automatically performed or manually initiated by the operator of the system  100 . 
     In some embodiments, the system  100  can perform a general search to detect each of the probes  110  that are located proximate to the base unit  120 . For example, an automatic search may begin once a user has specified various information about the usage of the system  100 , such as exam type, patient data, or similar information. In some embodiments, the system  100  may analyze which probes  110  are currently connected to the base unit  120  to determine if alternative options are required or more well suited for the various inputted information. In other embodiments, the operator of the system  100  can initiate a search for nearby probes  110  that have specific attributes by entering information into the base unit  120  via the operator controls  124 , or by selecting desired attributes of a particular imaging mode from a menu. The system  100  can then analyze the supplemental data received from the wireless tags  115  to identify the nearby probes  110  having the specified attributes. In a particular example, the operator of the system  100  could initiate a search for a probe  110  having a specific serial number. The base unit  120  can then send a request message to the wireless tag  115  associated with the probe  110  having the specific serial number and the wireless tag  115  can respond with its location. If the probe  110  cannot be detected, the operator could then walk around with or otherwise move the base unit  120  and, when the wireless tag  115  associated with the probe  110  having the specific serial number is within range, the system  100  could signal (e.g., via the display  122 , the speakers  256 , or another suitable output device) that the probe  110  having the specific serial number is nearby. In another example, the operator could enter a generic probe type to search for (e.g., a 5 MHz linear transducer) and the processor of the base unit  120  can transmit a request for probes  110  having the desired characteristics. If none are found, the operator can proceed to move the base unit  120  until the system  100  identifies a particular probe  110  of that type nearby. 
     In some embodiments, the system  100  is further configured to specifically locate the probes  110  relative to the base unit  120 . In some embodiments, for example, in response to an operator selection (e.g., in response to the operator selecting one of the proximate probes  110  from a list displayed on the display  122 ), the base unit  120  can send an instruction to the wireless tag  115  of the selected probe  110  to produce a sound via the speaker  268 . In some embodiments, the sound produced via the speaker  268  can be an audible sound (e.g., a chirp) that enables the operator to track and locate the selected probe  110 . In other embodiments, the sound produced via the speaker  268  can be an inaudible sound (e.g., having a frequency of greater than about 20 kHz) that is detectable by the microphones  255  of the base unit electronics  250 . In other embodiments, the base unit electronics  250  are configured to determine an approximate direction and/or to triangulate a specific position of the selected probe  110  relative to the base unit  120  based on, for example, a time difference between when the microphones  255  receive the sound from the wireless tag  115  of the selected probe  110 . If the wireless tag electronics  260  include a position sensor (GPS locator), the location of the selected probe  110  can be sent to the base unit  120 . The determined location or direction of the selected probe  110  can be outputted to the operator via the I/O devices  254 . In some embodiments, for example, the base unit  120  can be configured to generate and display one or more directional indicators on the display  122 . In certain embodiments, the directional indicators can vary in intensity based upon a determined distance from the base unit  120  to the selected probe  110 . 
     In yet other embodiments, the base unit  120  can include multiple wireless antennas  258  each configured (e.g., shaped and positioned) to detect wireless tags  115  located within a certain sector or angle relative to the base unit  120 . For example, the base unit electronics  250  could include three wireless antennas  258  each positioned to receive signals from wireless tags  115  in a different sector spanning about 120° around the base unit  120 . Accordingly, based on a particular one of the wireless antennas  258  that detects the selected probe  110 , the processor in the base unit  120  can determine an approximate direction or location of the selected probe  110  relative to the base unit  120 . In still other embodiments, the wireless antennas  258  could partially or fully overlap (e.g., the wireless antennas  258  could each be omnidirectional). In such embodiments, the time differences between when the different wireless antennas  258  detect the wireless tag  115  of the selected probe  110  could be used to determine an approximate direction and/or a specific position of the selected probe  110  relative to the base unit  120 . 
     In some embodiments, as described in detail above, the supplemental data stored within the wireless tags  115  includes location or storage information about the probes  110 , such as a normal storage location for each of the probes  110 . The normal storage locations can be average GPS positions for the probes  110 , or other descriptive information about the storage location of the probes—for example, that a particular one of the probes  110  is assigned to and normally stored in a particular drawer in a particular examination room. Accordingly, in such embodiments, the base unit  120  can simply display or otherwise indicate to the operator the assigned (e.g., normal) storage location of a selected probe  110 , the owner of the probe, performance capabilities, license data, and/or cost for use. 
     In certain embodiments, the system  100  can be configured to produce an alert (e.g., a visual or audible alert) when a probe  110  is moved out of range of the base unit  120  to reduce the likelihood of the probes  110  being lost or stolen. For example, if a periodic heart beat signal from one of the wireless tags  115  is lost (e.g., no longer detected by the base unit electronics  250 ) and/or below a threshold level, the system  100  can produce an audible alert via the speakers  256  of the base unit  120  and/or via the speaker  268  of the wireless tag  115 . In some embodiments, the system  100  can interface with multiple wireless scanners (e.g., Bluetooth scanners) strategically placed within a room or building to detect if the probes  110  are removed from the room or building. 
     The current method for detecting and locating nearby transducer probes requires that the operator of the ultrasound system look around and physically locate a desired transducer probe. The challenge of finding the transducer probe can be significant if the transducer probe is inside a drawer or otherwise out of sight—adding significant delay to an ultrasound imaging procedure. Accordingly, in contrast to conventional ultrasound systems, the present technology advantageously allows the operator of an ultrasound system to quickly view and/or locate nearby transducer probes. In addition, the present technology allows probes to be managed independently from a CPU system. 
     III. SELECTED EMBODIMENTS OF METHODS FOR DISPLAYING, FILTERING, AND SORTING PROXIMATE TRANSDUCER PROBES 
     With reference to  FIG.  1   , in some embodiments, the base unit  120  is configured to display a graphic on the display  122  showing the probes  110  that have been detected by the base unit  120  so that the operator of the system is informed of what probes  110  are nearby. The graphic can be any visual indication identifying the nearby probes  110  such as, for example, a list of serial numbers, images, physical characteristics, or other attributes of the probes  110 . In some embodiments, the base unit  120  can further display all or a portion of the supplemental data received from the wireless tags  115  associated with the nearby probes  110 . For example, the displayed graphic can include separate columns each identifying a different portion of the supplemental data associated with the nearby probes  110  (e.g., cleaning history, maintenance schedules, etc.). The displayed graphic could also include other indications based on the supplemental data—such as triangles with exclamation marks to distinguish the nearby probes  110  that need attention for maintenance or cleaning. 
     In some embodiments, the displayed graphic data can be manually or automatically sorted, filtered, augmented, etc., based on (i) the supplemental data received from the wireless tags  115  and/or (ii) an operator or other input to the system  100 . In particular, the data in the graphic can be updated or modified to distinguish certain ones of the nearby probes  110  using, for example, color coding, ranking (e.g., placing certain probes  110  at the top of a displayed list), list trimming (e.g., removing certain probes  110  from a displayed list), or any other suitable method or combination thereof for prioritizing, distinguishing, and/or emphasizing certain ones of the probes  110  on the display  122 . 
     In certain embodiments, for example, the operator of the system  100  can filter or sort the display of nearby probes  110  by manually entering information (e.g., a specific probe attribute) via the operator controls  124 , and the base unit  120  can update, modify, etc., the data in the graphic on the display  122  to show the nearby probes  110  that have that attribute. For example, an ultrasound technician responsible for maintenance of the system  100  may want to filter the display of nearby probes  110  to show those that require maintenance or cleaning, while a sonographer may want to filter the display of nearby probes  110  to show those that have specific physical characteristics appropriate for an imaging procedure to be carried out by the sonographer. In either instance, the relevant probes  110  could be displayed alone, displayed at the top of a list, displayed in a certain color, etc., in order to distinguish the probes  110  having the specified attribute to the ultrasound technician/sonographer. 
     In some embodiments, the current operator of the system  100  may enter their identity (e.g., ultrasound technician, sonographer, etc.) and the display of nearby probes  110  may be updated to distinguish those nearby probes  110  that may be more pertinent to the current operator. For example, those proximate probes  110  that need maintenance or cleaning may be more pertinent to the ultrasound technician, while the opposite is likely true for a sonographer seeking a probe for a current imaging procedure. In yet another example, the supplemental data may include information about sonographers&#39; preferred probes  110  (e.g., historical usage information), and the system  100  can display and/or distinguish those probes  110  after determining the identity of the sonographer using the system  100 . 
     In some embodiments, the current operator may not be familiar with the exam room and location of probes. The operator may display a list of all probes available for use which may include drawer location, license information, owner, cost for use, performance capabilities, system compatibility, etc. For example, if the probes are managed by a third party, newer or more capable probes (e.g. those having fewer dead elements, increased element count, lower loss, etc.) may be presented and cost the operator more for usage. 
     In some embodiments, the display of nearby probes  110  may be updated to distinguish at least one appropriate (e.g., suitable, preferred, etc.) or more appropriate one of the proximate probes  110  for an imaging procedure to be carried out on the patient  1 .  FIG.  3   , for example, is a flow diagram of a process or method  300  of selecting a nearby probe for an ultrasound imaging procedure using the system  100  in accordance with embodiments of the present technology. 
     Beginning at block  302 , the method  300  includes detecting the probes  110  that are located proximate to the base unit  120  and receiving supplemental data from the wireless tags  115  associated with the nearby probes  110 , as described in detail above. At block  304 , the method includes receiving information about the imaging procedure and/or information about the patient  1 . In some embodiments, for example, the operator (e.g., the sonographer) can use the operator controls  124  of the base unit  120  to enter or select information about the particular region of interest to be imaged, a particular feature to be imaged, the size/weight/height/age or other characteristic of the patient  1 , etc. In a particular example, the operator of the system  100  could specify that the imaging procedure is a peripheral vascular examination and that the targeted structure is a varicose vein located near the skin surface of the patient  1 . 
     At block  306 , the method  300  includes determining which, if any, of the nearby probes  110  are appropriate for the specific imaging procedure and patient. In some embodiments, the determination can be based at least in part on predetermined rules and/or historical data about probes used in previous imaging procedures and on patients having certain characteristics. The predetermined rules and historical data can be stored in the memory of the base unit  120  or otherwise made accessible to the base unit  120 . Continuing the particular example set forth above, the base unit  120  may determine that probes  110  having a higher frequency (e.g., 7.5 MHz) as opposed to a lower frequency (e.g., 5 MHz) are more appropriate for the peripheral vascular examination because the targeted varicose vein is located near the surface and thus the ultrasound waves need not penetrate as deeply and the resolution needed to find the vein is better with a high frequency probe. 
     As further examples of the determination at block  306 , the base unit  120  can determine that a probe  110  having a curved transducer array that operates between 1-5 MHz is most appropriate for imaging procedures that are abdominal, spinal, pulmonary, gynecological, musculoskeletal, and/or obstetric examinations. Further, in some embodiments, the base unit  120  can determine that a probe  110  having a linear transducer array that operates between 3-12 MHz is most appropriate for imaging procedures that are superficial, breast, arterial, venous, and/or ophthalmic examinations. Likewise, in certain embodiments, the base unit  120  can determine that a probe  110  having a phased transducer array that operates between 1-5 MHz is most appropriate for imaging procedures that are neurovascular examinations. 
     At block  308 , the method  300  includes displaying a graphic of the appropriate nearby probes  110  on the display  122 . As set forth in detail above, the graphic can suitably distinguish (e.g., via color coding, ranking, etc.) the appropriate nearby probes  110  from the inappropriate or less appropriate nearby probes  110 , or can list only the appropriate nearby probes  110 . For example, the appropriate nearby probes  110  could be displayed at the top of a list of all nearby probes. In some embodiments, the method  300  may return to block  304  as the operator enters additional information about the patient  1  and/or the current imaging procedure. The method  300  can then proceed again through blocks  306  and  308  to further update the display of appropriate nearby probes  110 . For example, the method  300  may proceed until only a single nearby probe  110  is displayed. If no appropriate probes  110  are detected, the graphic can include an indication that no appropriate probes  110  are nearby and, in some embodiments, can provide an indication of a determined next-best nearby probe  110  and/or an indication instructing the operator to search for nearby probes  110  in a different location (e.g., by moving the base unit  120  to another examination room in a medical facility). 
     In some embodiments, the system  100  can be configured to detect that one or more of the probes  110  are connected to the base unit  120  (e.g., via corresponding ones of the signal cables  130 ). Accordingly, the method  300  can further include determining whether the one or more connected probes  110  include the appropriate probes  110  as determined at block  306 . If the determined appropriate probe  110  is not connected to the base unit  120 , the method  300  can further include providing an indication or alert on the display  122  that the appropriate probe  110  is nearby but is not currently connected to the base unit  120 . That is, the system  100  may prompt the operator to connect a different one of the nearby probes  110 . 
     Some ultrasound imaging procedures are advantageously performed using two or more different probes (e.g., having different physical characteristics). Accordingly, in some embodiments, the method  300  can include determining two or more appropriate probes  110  based on received or selected information about the imaging procedure and/or the patient  1 . In such embodiments, at block  308 , the method  300  can include displaying the two or more appropriate probes  110  ordered or otherwise distinguished, for example, based on their presumptive order of use during the imaging procedure. Where the base unit  120  can be connected to two more of the probes  110 , the display of nearby probes  110  can further include an indication of a particular I/O port  126  in which each of the appropriate probes  110  should be connected. 
     Current ultrasound systems rely on the experience of the operator and the records of the facility housing the ultrasound system to guide the operator in selecting a particular probe for a particular examination or for cleaning, maintenance, etc. In particular, it may be difficult for ultrasound technicians to reliably locate probes that need service, and sonographers may often select an inappropriate or less appropriate probe for a procedure than what is available nearby. Accordingly, in contrast to conventional ultrasound systems, the present technology advantageously permits operators to search for nearby probes having particular attributes of interest and can also guide operators in the selection of the most appropriate available probe. 
     IV. CONCLUSION 
     Embodiments of the subject matter and the operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on computer storage medium for execution by, or to control the operation of, data processing apparatus. 
     A computer storage medium can be, or can be included in, a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them. Moreover, while a computer storage medium is not a propagated signal, a computer storage medium can be a source or destination of computer program instructions encoded in an artificially-generated propagated signal. The computer storage medium also can be, or can be included in, one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices). The operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources. 
     The term “processor” encompasses all kinds of apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, a system on a chip, or multiple ones, or combinations, of the foregoing. The apparatus can include special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). The apparatus also can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, a cross-platform runtime environment, a virtual machine, or a combination of one or more of them. The apparatus and execution environment can realize various different computing model infrastructures, such as web services, distributed computing and grid computing infrastructures. 
     A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but need not, correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub-programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network. 
     The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform actions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). 
     Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for performing actions in accordance with instructions and one or more memory devices for storing instructions and data. To provide for interaction with a user, embodiments of the subject matter described in this specification can be implemented on a imaging system having a display device, e.g., an LCD (liquid crystal display), LED (light emitting diode), or OLED (organic light emitting diode) monitor, for displaying information to the operator and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the operator can provide input to the computer. In some implementations, a touch screen can be used to display information and to receive input from a user. Other kinds of devices can be used to provide for interaction with an operator as well; for example, feedback provided to the operator can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the operator can be received in any form, including acoustic, speech, or tactile input. 
     From the foregoing, it will be appreciated that specific embodiments of the technology have been described herein for purposes of illustration, but that various modifications may be made without deviating from the disclosure. Accordingly, the invention is not limited except as by the appended claims. Furthermore, certain aspects of the new technology described in the context of particular embodiments may also be combined or eliminated in other embodiments. Moreover, although advantages associated with certain embodiments of the new technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.