Abstract:
A system includes an array of N electrode elements configured to be attached to an external region of a patient, and a processing device coupled to the array. The processing device is configured to receive a set of bioelectric data signals from the array, determine from the set of data signals a set of elements of the array that are, according to a predetermined standard, insufficiently attached to the external region, and generate to a display device, in at least two dimensions, a representation of the external region and the spatial positioning of the insufficiently attached set of elements on the external region.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Sensor devices that can monitor bioelectric data from a body are known. An example of such a device is described in U.S. Pat. No. 6,055,448. The apparatus described therein comprises an array of a plurality of N number of sensors where N is an integer, each sensor of which is capable of detecting an electrical signal associated with components of a heartbeat. In an associated known approach to monitoring the electrical signals detected by the sensors, executable instructions implemented by a processing device generate an indication of the quality of contact between each respective sensor of the array and the body of a patient, the heartbeat of whom the sensors are to monitor. Poor quality of contact between a sensor of the array and the body of the patient will produce a poor-quality signal, thereby preventing an optimal evaluation of the monitored heartbeat. 
         [0002]    While this quality-of-contact evaluation functions to specifically indicate which one(s) of the sensor(s) is in poor contact with the patient, in the instance in which N is a comparatively high number, it is nonetheless difficult for a practitioner employing the sensor array to discern the specific position on the patient&#39;s body at which sensor contact quality is poor or otherwise insufficient. 
       SUMMARY OF THE INVENTION 
       [0003]    In an embodiment, a system includes an array of N electrode elements configured to be attached to an external region of a patient, and a processing device coupled to the array. The processing device is configured to receive a set of bioelectric data signals from the array, determine from the set of data signals a set of elements of the array that are, according to a predetermined standard, insufficiently attached to the external region, and generate to a display device, in at least two dimensions, a representation of the external region and the spatial positioning of the insufficiently attached set of elements on the external region. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0004]    Preferred and alternative embodiments of the present invention are described in detail below with reference to the following figures: 
           [0005]      FIG. 1  is a high-level block diagram showing an ECG system  100  in accordance with an embodiment of the invention; 
           [0006]      FIG. 2  is a schematic illustration of an arrangement of N electrodes in an array in accordance with an embodiment of the invention 
           [0007]      FIG. 3  illustrates a graphical user interface according to an embodiment of the invention; and 
           [0008]      FIG. 4  illustrates an exemplary respective connector-pin assignment for interfaces of the connector element  120  and console  130  of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0009]    Embodiments of the invention are operational with numerous general purpose or special purpose computing system environments or configurations. Examples of well known computing systems, environments, and/or configurations that may be suitable for use with the invention include, but are not limited to, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like. 
         [0010]    Embodiments of the invention may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer and/or by computer-readable media on which such instructions or modules can be stored. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices. 
         [0011]    Embodiments of the invention may include or be implemented in a variety of computer readable media. Computer readable media can be any available media that can be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by computer. Communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of the any of the above should also be included within the scope of computer readable media. 
         [0012]    According to one or more embodiments, the combination of software or computer-executable instructions with a computer-readable medium results in the creation of a machine or apparatus. Similarly, the execution of software or computer-executable instructions by a processing device results in the creation of a machine or apparatus, which may be distinguishable from the processing device, itself, according to an embodiment. 
         [0013]    Correspondingly, it is to be understood that a computer-readable medium is transformed by storing software or computer-executable instructions thereon. Likewise, a processing device is transformed in the course of executing software or computer-executable instructions. Additionally, it is to be understood that a first set of data input to a processing device during, or otherwise in association with, the execution of software or computer-executable instructions by the processing device is transformed into a second set of data as a consequence of such execution. This second data set may subsequently be stored, displayed, or otherwise communicated. Such transformation, alluded to in each of the above examples, may be a consequence of, or otherwise involve, the physical alteration of portions of a computer-readable medium. Such transformation, alluded to in each of the above examples, may also be a consequence of, or otherwise involve, the physical alteration of, for example, the states of registers and/or counters associated with a processing device during execution of software or computer-executable instructions by the processing device. 
         [0014]    An embodiment of the invention enables a display device to display on a 3-D model of a torso the current status of electrode connectivity to assist a user in correcting poor-quality electrode contacts, as appropriate. 
         [0015]      FIG. 1  is a high-level block diagram showing an ECG system  100  according to an embodiment. System  100  includes an N-lead electrode array  110 , a connector element  120 , and a signal-monitoring console  130  including, or otherwise coupled to, a processing device (processor)  140 . 
         [0016]    According to an embodiment of the invention, the processor  140  employs a chip (not shown), such as a Texas Instruments® AD  1298  chip, 8 channel 24 bit ECG AFE, for ECG data acquisition. Alternatively, the chip may be a component of the connector element  120 . This chip provides a “lead-off” detection function using, for example, internal 10 MΩ pull-up resistors to detect whether one or more electrodes of the array  110  is in poor contact with the body of a patient (not shown). The indication of “lead-off” may be binary (i.e., ON or OFF). 
         [0017]      FIG. 2  is a schematic illustration of the arrangement of the N electrodes in an embodiment of the array  110 . In the illustrated embodiment, the array  110  includes an anterior sub-array  210  (i.e., leads  1 - 61 ) configured to be positioned on the front of a patient&#39;s torso and a posterior sub-array  220  (i.e., leads  62 - 77 ) configured to be positioned on the back of a patient&#39;s torso. The connector element  120  may be configured to provide a common electrical interface to the console  130  for both the anterior and posterior sub-arrays  210 ,  220 . 
         [0018]      FIG. 3  illustrates a graphical user interface  300  according to an embodiment that may be employed by a user of the system  100  to perform a lead-contact-quality check. Once each lead of the array  110  has been attached to the patient, the user may, using a conventional pointer device, select a test-initiation button  310  to commence the contact-quality check. 
         [0019]    Upon completion of the check, the interface  300  may display a first representation  320  of the front of the patient torso and the spatial positioning of sufficiently and insufficiently attached leads of the anterior sub-array  210 . The interface  300  may additionally display a second representation  330  of the back of the patient torso and the spatial positioning of sufficiently and insufficiently attached leads of the posterior sub-array  220 . The sufficiently attached leads may be illustrated in the interface  300  in a first format (e.g., “+” signs, as shown in  FIG. 3 ) different from a second format (e.g., dots, as shown in  FIG. 3 ) in which the insufficiently attached leads are illustrated. In this manner, the system  100  offers the user a more-intuitive “mapping” of the torso location of leads that require corrective attachment. 
         [0020]    Each of the representations  320 ,  330  may be rotated in three dimensions within the interface  300 , using a conventional input device, by the user to offer multiple views of the positioning of insufficiently attached leads relative to the patient&#39;s torso. Additionally, the interface  300  may include an indication, such as a meter  340 , of the quantity of the insufficiently attached leads. 
         [0021]    It may be desirable to ensure compatibility between the connector element  120  and console  130  as a means of enabling, or disabling, electrical communication between the console and the array  110 . In an embodiment, this may be achieved by employing pull-up and/or pull-down combinations in the connector pins of the connector element  120  and console  130  as a means of implementing an “identification code.” 
         [0022]    In such an embodiment, the array  110  is connected by pin connection to the connector element  120 . In turn, the connector element  120  may be connected to the console  130  with, for example, 20-wire cable. An exemplary respective connector-pin assignment for an interface  410  of the connector element  120  and an interface  420  of the console  130  is illustrated in  FIG. 4 . 
         [0023]    Table 1 illustrates an exemplary pin assignment table describing the connection between interfaces  410  and  420 . 
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                   
                 Interface 
                 Interface 
                   
               
               
                   
                 Name 
                 420 
                 410 
                 Status 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 GND (high imp) 
                 1 
                 2 
                   
               
               
                   
                 5 V 
                 2 
                 4 
               
               
                   
                 SPI_CLK 
                 3 
                 14 
               
               
                   
                 GND (high imp) 
                 4 
                 12 
               
               
                   
                   
                 5 
               
               
                   
                   
                 6 
               
               
                   
                 SPI_START 
                 7 
                 11 
               
               
                   
                 SPI_DRDY 
                 8 
                 13 
               
               
                   
                   
                 9 
                 1 
                 0 
               
               
                   
                 SPI_OUT 
                 10 
                 3 
               
               
                   
                 SPI_CS0 
                 11 
                 7 
               
               
                   
                 SPI_IN 
                 12 
                 5 
               
               
                   
                 PWDNB (3.3 V pull up) 
                 13 
                 6 
                 1 
               
               
                   
                   
                 14 
               
               
                   
                   
                 15 
               
               
                   
                   
                 16 
               
               
                   
                 RESETB (3.3 V pull up) 
                 17 
                 8 
                 1 
               
               
                   
                   
                 18 
               
               
                   
                 SPI_CS1 
                 19 
                 9 
               
               
                   
                 GND 
                 20 
                 10 
               
               
                   
                   
               
             
          
         
       
     
         [0024]    In an embodiment, when the main power input, 5V, is applied to pin  2  of interface  420  of the console  130 , the pin status of pins  13  and  17  of interface  420  is high, as two pins may be pulled-up to 3.3V from interface  410  of the connector element  120 . By pulling-down pin  1  of interface  410  of the connector element  120  and pulling up pin  9  of interface  420 , an additional low line may be achieved. In this manner, the number of potential predetermined combinations that may be used as the above-referenced “ID code” is 2 3 =8. As such, in this example, by reading pins  9 ,  13  and  17  of interface  420 , compatibility between the connector element  120  and console  130  can be ensured. 
         [0025]    While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.