Patent Publication Number: US-2021178171-A1

Title: User interface with view finder for localizing anatomical region

Description:
RELATED APPLICATION DATA 
     The present application is a continuation of U.S. application Ser. No. 16/237,505, filed Dec. 31, 2018, which is a continuation of U.S. application Ser. No. 15/254,422, filed Sep. 1, 2016, now issued as U.S. Pat. No. 10,213,607, which is a continuation of U.S. application Ser. No. 13/445,179, filed Apr. 12, 2012, now issued as U.S. Pat. No. 9,433,795, which claims the benefit under 35 U.S.C. § 119 to U.S. provisional patent application Ser. No. 61/474,884, filed Apr. 13, 2011. The foregoing applications are hereby incorporated by reference into the present application in their entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to medical systems, and more particularly, to a user interface for displaying anatomical regions of patients. 
     BACKGROUND OF THE INVENTION 
     Implantable neurostimulation systems have proven therapeutic in a wide variety of diseases and disorders. Pacemakers and Implantable Cardiac Defibrillators (ICDs) have proven highly effective in the treatment of a number of cardiac conditions (e.g., arrhythmias). Spinal Cord Stimulation (SCS) systems have long been accepted as a therapeutic modality for the treatment of chronic pain syndromes, and the application of tissue stimulation has begun to expand to additional applications such as angina pectoralis and incontinence. Deep Brain Stimulation (DBS) has also been applied therapeutically for well over a decade for the treatment of refractory chronic pain syndromes, and DBS has also recently been applied in additional areas such as movement disorders and epilepsy. Further, in recent investigations Peripheral Nerve Stimulation (PNS) systems have demonstrated efficacy in the treatment of chronic pain syndromes and incontinence, and a number of additional applications are currently under investigation. Also, Functional Electrical Stimulation (FES) systems such as the Freehand system by NeuroControl (Cleveland, Ohio) have been applied to restore some functionality to paralyzed extremities in spinal cord injury patients. 
     These implantable neurostimulation systems typically include one or more electrode carrying neurostimulation leads, which are implanted at the desired stimulation site, and a neurostimulator (e.g., an implantable pulse generator (IPG)) implanted remotely from the stimulation site, but coupled either directly to the neurostimulation lead(s) or indirectly to the neurostimulation lead(s) via a lead extension. Thus, electrical pulses can be delivered from the neurostimulator to the neurostimulation leads to stimulate the tissue and provide the desired efficacious therapy to the patient. The neurostimulation system may further comprise a handheld patient programmer in the form of a remote control (RC) to remotely instruct the neurostimulator to generate electrical stimulation pulses in accordance with selected stimulation parameters. The RC may, itself, be programmed by a clinician, for example, by using a clinician&#39;s programmer (CP), which typically includes a general purpose computer, such as a laptop, with a programming software package installed thereon. 
     In the context of an SCS procedure, one or more neurostimulation leads are introduced through the patient&#39;s back into the epidural space, such that the electrodes carried by the leads are arranged in a desired pattern and spacing to create an electrode array. Multi-lead configurations have been increasingly used in electrical stimulation applications (e.g., neurostimulation, cardiac resynchronization therapy, etc.). In the neurostimulation application of SCS, the use of multiple leads increases the stimulation area and penetration depth (therefore coverage), as well as enables more combinations of anodic and cathodic electrodes for stimulation, such as transverse multipolar (bipolar, tripolar, or quadra-polar) stimulation, in addition to any longitudinal single lead configuration. After proper placement of the neurostimulation leads at the target area of the spinal cord, the leads are anchored in place at an exit site to prevent movement of the neurostimulation leads. To facilitate the location of the neurostimulator away from the exit point of the neurostimulation leads, lead extensions are sometimes used. 
     The neurostimulation leads, or the lead extensions, are then connected to the IPG, which can then be operated to generate electrical pulses that are delivered, through the electrodes, to the targeted tissue, and in particular, the dorsal column and dorsal root fibers within the spinal cord. The stimulation creates the sensation known as paresthesia, which can be characterized as an alternative sensation that replaces the pain signals sensed by the patient. 
     The efficacy of SCS is related to the ability to stimulate the spinal cord tissue corresponding to evoked paresthesia in the region of the body where the patient experiences pain. Thus, the working clinical paradigm is that achievement of an effective result from SCS depends on the neurostimulation lead or leads being placed in a location (both longitudinal and lateral) relative to the spinal tissue such that the electrical stimulation will induce paresthesia located in approximately the same place in the patient&#39;s body as the pain (i.e., the target of treatment). If a lead is not correctly positioned, it is possible that the patient will receive little or no benefit from an implanted SCS system. Thus, correct lead placement can mean the difference between effective and ineffective pain therapy. 
     As such, the CP (described briefly above) may be used to instruct the neurostimulator to apply electrical stimulation to test placement of the leads and/or electrodes inter-operatively (i.e., in the context of an operating room (OR) mapping procedure), thereby assuring that the leads and/or electrodes are implanted in effective locations within the patient. The patient may provide verbal feedback regarding the presence of paresthesia over the pain area, and based on this feedback, the lead positions may be adjusted and re-anchored if necessary. Any incisions are then closed to fully implant the system. 
     Post-operatively (i.e., after the surgical procedure has been completed), a fitting procedure, which may be referred to as a navigation session, may be performed using the CP to program the RC, and if applicable the IPG, with a set of stimulation parameters that best addresses the painful site, thereby optimizing or re-optimizing the therapy. Thus, the navigation session may be used to pinpoint the stimulation region or areas correlating to the pain. Such programming ability is particularly advantageous after implantation should the leads gradually or unexpectedly move, which if uncorrected, would relocate the paresthesia away from the pain site. 
     Typical programmable neurostimulation systems require a means to locate and navigate to a targeted implant location. For example, in the context of SCS, the CP may display graphical representations of the neurostimulation leads in relation to the spinal column of the patient, as described in U.S. Provisional Patent Application Ser. No. 61/390,112, entitled Neurostimulation System and Method with Anatomy and Physiology Driven Programming,” which is expressly incorporated herein by reference. Because it is desirable that the entire work area for an implant be displayed to medical personnel, current neurostimulation systems should display the entire spinal column, since neurostimulation leads can be implanted anywhere within the spinal column. However, because the size of a neurostimulation lead is much smaller than that of the spinal column, standard user interfaces are limited in that displaying the neurostimulation leads in the context of the entire spinal column may render any details of the neurostimulation leads and the immediately relevant region of the spinal column illegible. 
     There, thus, remains a need to provide a user interface capable of displaying an implant in the context of the entire work area while also displaying any details of the implant and the immediately surrounding portion of the work area in a legible manner. 
     SUMMARY OF THE INVENTION 
     In accordance with the present inventions, an external control device for use with a medical component (e.g., a neurostimulation lead) implanted within a patient is provided. The external control device comprises a user interface configured for receiving input from a user, displaying a first graphical representation of the medical component in the context of a global view of an anatomical region (e.g., a spinal column) of the patient, displaying a view finder (e.g., a box) spatially defining a portion of the global graphical representation of the anatomical region, and displaying a second graphical representation of the medical component in the context of a local graphical representation of the portion of the anatomical region portion spatially defined by the view finder. 
     The external control device further comprises control circuitry configured for, in response to the input from the user, modifying displayed view finder to spatially define a different portion of the global graphical representation of the anatomical region, such that the second graphical representation of the medical component is displayed in the context of a local graphical representation of the different portion of the anatomical region. The control circuitry may be configured for, in response to the input from the user, modifying the displayed view finder by changing a position of the displayed view finder relative to the global graphical representation. In one embodiment, the control circuitry is configured for, in response to the input from the user, limiting the change in the position of the displayed view finder in one dimension. In another embodiment, the control circuitry is configured for, in response to the input from the user, changing the position of the displayed view finder in two dimensions. The control circuitry may alternatively or additionally be configured for, in response to the input from the user, modifying the displayed view finder by changing a size of the displayed view finder. 
     In one embodiment, the user interface comprises a control element configured for being manipulated by the user, and the control circuitry is configured for modifying the displayed view finder to spatially define the different portion of the global graphical representation of the anatomical region in response to the user manipulation of the control element, e.g., a graphical control element. The graphical control element may be disposed on the view finder. Or, the graphical control element may be separate from the view finder. For example, the graphical control element may comprise a graphical slider bar. The user input may comprise manipulating a pointing device, in which case, the graphical control element may be configured for being manipulated via the pointing device. 
     In an optional embodiment, the control circuitry is further configured for, in response to additional input from the user, defining a location of the graphical representation of the medical device relative to at least one of the global graphical representation of the anatomical region and the local graphical representation of the portion of the anatomical region. In another optional embodiment, the control circuitry is further configured for, in response to additional input from the user, programming the medical component. 
     Other and further aspects and features of the invention will be evident from reading the following detailed description of the preferred embodiments, which are intended to illustrate, not limit, the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate the design and utility of preferred embodiments of the present invention, in which similar elements are referred to by common reference numerals. In order to better appreciate how the above-recited and other advantages and objects of the present inventions are obtained, a more particular description of the present inventions briefly described above will be rendered by reference to specific embodiments thereof, which are illustrated in the accompanying drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIG. 1  is perspective view of one embodiment of a SCS system arranged in accordance with the present inventions; 
         FIG. 2  is a plan view of the SCS system of  FIG. 1  in use with a patient; 
         FIG. 3  is a side view of an implantable pulse generator and a pair of stimulation leads that can be used in the SCS system of  FIG. 1 ; 
         FIG. 4  is a plan view of a remote control that can be used in the SCS system of  FIG. 1 ; 
         FIG. 5  is a block diagram of the internal componentry of the remote control of  FIG. 4 ; 
         FIG. 6  is a block diagram of the components of a clinician programmer that can be used in the SCS system of  FIG. 1 ; 
         FIG. 7  is an illustration of a lead configuration screen that can be displayed by the clinician programmer of  FIG. 6 , wherein a graphical lead configuration is displayed over a composite graphical representation of a spinal column; 
         FIG. 8  is an illustration of the lead configuration screen of  FIG. 7 , wherein a view finder is displaced along the spinal column; 
         FIG. 9  is an illustration of the lead configuration screen of  FIG. 7 , wherein the view finder is expanded; and 
         FIG. 10  is an illustration of the lead configuration screen of  FIG. 7 , wherein the view finder is contracted. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The description that follows relates to a spinal cord stimulation (SCS) system. However, it is to be understood that the while the invention lends itself well to applications in SCS, the invention, in its broadest aspects, may not be so limited. Rather, the invention may be used with any type of implantable electrical circuitry used to stimulate tissue. For example, the present invention may be used as part of a pacemaker, a defibrillator, a cochlear stimulator, a retinal stimulator, a stimulator configured to produce coordinated limb movement, a cortical stimulator, a deep brain stimulator, peripheral nerve stimulator, microstimulator, or in any other neural stimulator configured to treat urinary incontinence, sleep apnea, shoulder sublaxation, headache, etc. 
     Turning first to  FIG. 1 , an exemplary SCS system  10  generally includes a plurality (in this case, two) of implantable neurostimulation leads  12 , an implantable pulse generator (IPG)  14 , an external remote controller RC  16 , a clinician&#39;s programmer (CP)  18 , an external trial stimulator (ETS)  20 , and an external charger  22 . 
     The IPG  14  is physically connected via one or more percutaneous lead extensions  24  to the neurostimulation leads  12 , which carry a plurality of electrodes  26  arranged in an array. In the illustrated embodiment, the neurostimulation leads  12  are percutaneous leads, and to this end, the electrodes  26  are arranged in-line along the neurostimulation leads  12 . The number of neurostimulation leads  12  illustrated is two, although any suitable number of neurostimulation leads  12  can be provided, including only one. Alternatively, a surgical paddle lead in can be used in place of one or more of the percutaneous leads. As will be described in further detail below, the IPG  14  includes pulse generation circuitry that delivers electrical stimulation energy in the form of a pulsed electrical waveform (i.e., a temporal series of electrical pulses) to the electrode array  26  in accordance with a set of stimulation parameters. 
     The ETS  20  may also be physically connected via the percutaneous lead extensions  28  and external cable  30  to the neurostimulation leads  12 . The ETS  20 , which has similar pulse generation circuitry as the IPG  14 , also delivers electrical stimulation energy in the form of a pulse electrical waveform to the electrode array  26  accordance with a set of stimulation parameters. The major difference between the ETS  20  and the IPG  14  is that the ETS  20  is a non-implantable device that is used on a trial basis after the neurostimulation leads  12  have been implanted and prior to implantation of the IPG  14 , to test the responsiveness of the stimulation that is to be provided. Thus, any functions described herein with respect to the IPG  14  can likewise be performed with respect to the ETS  20 . Further details of an exemplary ETS are described in U.S. Pat. No. 6,895,280, which is expressly incorporated herein by reference. 
     The RC  16  may be used to telemetrically control the ETS  20  via a bi-directional RF communications link  32 . Once the IPG  14  and neurostimulation leads  12  are implanted, the RC  16  may be used to telemetrically control the IPG  14  via a bi-directional RF communications link  34 . Such control allows the IPG  14  to be turned on or off and to be programmed with different stimulation parameter sets. The IPG  14  may also be operated to modify the programmed stimulation parameters to actively control the characteristics of the electrical stimulation energy output by the IPG  14 . As will be described in further detail below, the CP  18  provides clinician detailed stimulation parameters for programming the IPG  14  and ETS  20  in the operating room and in follow-up sessions. 
     The CP  18  may perform this function by indirectly communicating with the IPG  14  or ETS  20 , through the RC  16 , via an IR communications link  36 . Alternatively, the CP  18  may directly communicate with the IPG  14  or ETS  20  via an RF communications link (not shown). The clinician detailed stimulation parameters provided by the CP  18  are also used to program the RC  16 , so that the stimulation parameters can be subsequently modified by operation of the RC  16  in a stand-alone mode (i.e., without the assistance of the CP  18 ). 
     The external charger  22  is a portable device used to transcutaneously charge the IPG  14  via an inductive link  38 . For purposes of brevity, the details of the external charger  22  will not be described herein. Details of exemplary embodiments of external chargers are disclosed in U.S. Pat. No. 6,895,280, which has been previously incorporated herein by reference. Once the IPG  14  has been programmed, and its power source has been charged by the external charger  22  or otherwise replenished, the IPG  14  may function as programmed without the RC  16  or CP  18  being present. 
     As shown in  FIG. 2 , the neurostimulation leads  12  are implanted within the spinal column  42  of a patient  40 . The preferred placement of the neurostimulation leads  12  is adjacent, i.e., resting upon, the spinal cord area to be stimulated. Due to the lack of space near the location where the neurostimulation leads  12  exit the spinal column  42 , the IPG  14  is generally implanted in a surgically-made pocket either in the abdomen or above the buttocks. The IPG  14  may, of course, also be implanted in other locations of the patient&#39;s body. The lead extension  24  facilitates locating the IPG  14  away from the exit point of the neurostimulation leads  12 . As there shown, the CP  18  communicates with the IPG  14  via the RC  16 . 
     Referring now to  FIG. 3 , the external features of the neurostimulation leads  12  and the IPG  14  will be briefly described. One of the neurostimulation leads  12   a  has eight electrodes  26  (labeled E 1 -E 8 ), and the other stimulation lead  12   b  has eight electrodes  26  (labeled E 9 -E 16 ). The actual number and shape of leads and electrodes will, of course, vary according to the intended application. The IPG  14  comprises an outer case  40  for housing the electronic and other components (described in further detail below), and a connector  42  to which the proximal ends of the neurostimulation leads  12  mates in a manner that electrically couples the electrodes  26  to the electronics within the outer case  40 . The outer case  40  is composed of an electrically conductive, biocompatible material, such as titanium, and forms a hermetically sealed compartment wherein the internal electronics are protected from the body tissue and fluids. In some cases, the outer case  40  may serve as an electrode. 
     The IPG  14  includes a battery and pulse generation circuitry that delivers the electrical stimulation energy in the form of a pulsed electrical waveform to the electrode array  26  in accordance with a set of stimulation parameters programmed into the IPG  14 . Such stimulation parameters may comprise electrode combinations, which define the electrodes that are activated as anodes (positive), cathodes (negative), and turned off (zero), percentage of stimulation energy assigned to each electrode (fractionalized electrode configurations), and electrical pulse parameters, which define the pulse amplitude (measured in milliamps or volts depending on whether the IPG  14  supplies constant current or constant voltage to the electrode array  26 ), pulse width (measured in microseconds), and pulse rate (measured in pulses per second). 
     Electrical stimulation will occur between two (or more) activated electrodes, one of which may be the IPG case. Simulation energy may be transmitted to the tissue in a monopolar or multipolar (e.g., bipolar, tripolar, etc.) fashion. Monopolar stimulation occurs when a selected one of the lead electrodes  26  is activated along with the case of the IPG  14 , so that stimulation energy is transmitted between the selected electrode  26  and case. Bipolar stimulation occurs when two of the lead electrodes  26  are activated as anode and cathode, so that stimulation energy is transmitted between the selected electrodes  26 . For example, electrode E 3  on the first lead  12  may be activated as an anode at the same time that electrode E 11  on the second lead  12  is activated as a cathode. Tripolar stimulation occurs when three of the lead electrodes  26  are activated, two as anodes and the remaining one as a cathode, or two as cathodes and the remaining one as an anode. For example, electrodes E 4  and E 5  on the first lead  12  may be activated as anodes at the same time that electrode E 12  on the second lead  12  is activated as a cathode. 
     In the illustrated embodiment, IPG  14  can individually control the magnitude of electrical current flowing through each of the electrodes. In this case, it is preferred to have a current generator, wherein individual current-regulated amplitudes from independent current sources for each electrode may be selectively generated. Although this system is optimal to take advantage of the invention, other stimulators that may be used with the invention include stimulators having voltage regulated outputs. While individually programmable electrode amplitudes are optimal to achieve fine control, a single output source switched across electrodes may also be used, although with less fine control in programming. Mixed current and voltage regulated devices may also be used with the invention. Further details discussing the detailed structure and function of IPGs are described more fully in U.S. Pat. Nos. 6,516,227 and 6,993,384, which are expressly incorporated herein by reference. 
     It should be noted that rather than an IPG, the SCS system  10  may alternatively utilize an implantable receiver-stimulator (not shown) connected to the neurostimulation leads  12 . In this case, the power source, e.g., a battery, for powering the implanted receiver, as well as control circuitry to command the receiver-stimulator, will be contained in an external controller inductively coupled to the receiver-stimulator via an electromagnetic link. Data/power signals are transcutaneously coupled from a cable-connected transmission coil placed over the implanted receiver-stimulator. The implanted receiver-stimulator receives the signal and generates the stimulation in accordance with the control signals. 
     Referring now to  FIG. 4 , one exemplary embodiment of an RC  16  will now be described. As previously discussed, the RC  16  is capable of communicating with the IPG  14 , CP  18 , or ETS  20 . The RC  16  comprises a casing  50 , which houses internal componentry (including a printed circuit board (PCB)), and a lighted display screen  52  and button pad  54  carried by the exterior of the casing  50 . In the illustrated embodiment, the display screen  52  is a lighted flat panel display screen, and the button pad  54  comprises a membrane switch with metal domes positioned over a flex circuit, and a keypad connector connected directly to a PCB. In an optional embodiment, the display screen  52  has touchscreen capabilities. The button pad  54  includes a multitude of buttons  56 ,  58 ,  60 , and  62 , which allow the IPG  14  to be turned ON and OFF, provide for the adjustment or setting of stimulation parameters within the IPG  14 , and provide for selection between screens. 
     In the illustrated embodiment, the button  56  serves as an ON/OFF button that can be actuated to turn the IPG  14  ON and OFF. The button  58  serves as a select button that allows the RC  16  to switch between screen displays and/or parameters. The buttons  60  and  62  serve as up/down buttons that can be actuated to increment or decrement any of stimulation parameters of the pulse generated by the IPG  14 , including pulse amplitude, pulse width, and pulse rate. For example, the selection button  58  can be actuated to place the RC  16  in a “Pulse Amplitude Adjustment Mode,” during which the pulse amplitude can be adjusted via the up/down buttons  60 ,  62 , a “Pulse Width Adjustment Mode,” during which the pulse width can be adjusted via the up/down buttons  60 ,  62 , and a “Pulse Rate Adjustment Mode,” during which the pulse rate can be adjusted via the up/down buttons  60 ,  62 . Alternatively, dedicated up/down buttons can be provided for each stimulation parameter. Rather than using up/down buttons, any other type of actuator, such as a dial, slider bar, or keypad, can be used to increment or decrement the stimulation parameters. Further details of the functionality and internal componentry of the RC  16  are disclosed in U.S. Pat. No. 6,895,280, which has previously been incorporated herein by reference. 
     Referring to  FIG. 5 , the internal components of an exemplary RC  16  will now be described. The RC  16  generally includes a processor  64  (e.g., a microcontroller), memory  66  that stores an operating program for execution by the processor  64 , as well as stimulation parameter sets in a navigation table (described below), input/output circuitry, and in particular, telemetry circuitry  68  for outputting stimulation parameters to the IPG  14  and receiving status information from the IPG  14 , and input/output circuitry  70  for receiving stimulation control signals from the button pad  54  and transmitting status information to the display screen  52  (shown in  FIG. 4 ). As well as controlling other functions of the RC  16 , which will not be described herein for purposes of brevity, the processor  64  generates new stimulation parameter sets in response to the user operation of the button pad  54 . These new stimulation parameter sets would then be transmitted to the IPG  14  via the telemetry circuitry  68 . Further details of the functionality and internal componentry of the RC  16  are disclosed in U.S. Pat. No. 6,895,280, which has previously been incorporated herein by reference. 
     As briefly discussed above, the CP  18  greatly simplifies the programming of multiple electrode combinations, allowing the user (e.g., the physician or clinician) to readily determine the desired stimulation parameters to be programmed into the IPG  14 , as well as the RC  16 . Thus, modification of the stimulation parameters in the programmable memory of the IPG  14  after implantation is performed by a user using the CP  18 , which can directly communicate with the IPG  14  or indirectly communicate with the IPG  14  via the RC  16 . That is, the CP  18  can be used by the user to modify operating parameters of the electrode array  26  near the spinal cord. 
     As shown in  FIG. 2 , the overall appearance of the CP  18  is that of a laptop personal computer (PC), and in fact, may be implemented using a PC that has been appropriately configured to include a directional-programming device and programmed to perform the functions described herein. Alternatively, the CP  18  may take the form of a mini-computer, personal digital assistant (PDA), etc., or even a remote control (RC) with expanded functionality. Thus, the programming methodologies can be performed by executing software instructions contained within the CP  18 . Alternatively, such programming methodologies can be performed using firmware or hardware. In any event, the CP  18  may actively control the characteristics of the electrical stimulation generated by the IPG  14  to allow the optimum stimulation parameters to be determined based on patient feedback and for subsequently programming the IPG  14  with the optimum stimulation parameters. 
     To allow the user to perform these functions, the CP  18  includes a mouse  72 , a keyboard  74 , and a programming display screen  76  housed in a case  78 . It is to be understood that in addition to, or in lieu of, the mouse  72 , other directional programming devices may be used, such as a trackball, touchpad, joystick, or directional keys included as part of the keys associated with the keyboard  74 . 
     In the illustrated embodiment described below, the display screen  76  takes the form of a conventional screen, in which case, a virtual pointing device, such as a cursor controlled by a mouse, joy stick, trackball, etc, can be used to manipulate graphical objects on the display screen  76 . In alternative embodiments, the display screen  76  takes the form of a digitizer touch screen, which may either passive or active. If passive, the display screen  76  includes detection circuitry that recognizes pressure or a change in an electrical current when a passive device, such as a finger or non-electronic stylus, contacts the screen. If active, the display screen  76  includes detection circuitry that recognizes a signal transmitted by an electronic pen or stylus. In either case, detection circuitry is capable of detecting when a physical pointing device (e.g., a finger, a non-electronic stylus, or an electronic stylus) is in close proximity to the screen, whether it be making physical contact between the pointing device and the screen or bringing the pointing device in proximity to the screen within a predetermined distance, as well as detecting the location of the screen in which the physical pointing device is in close proximity. When the pointing device touches or otherwise is in close proximity to the screen, the graphical object on the screen adjacent to the touch point is “locked” for manipulation, and when the pointing device is moved away from the screen the previously locked object is unlocked. 
     As shown in  FIG. 6 , the CP  18  generally includes control circuitry  80  (e.g., a central processor unit (CPU)) and memory  82  that stores a stimulation programming package  84 , which can be executed by the control circuitry  80  to allow the user to program the IPG  14 , and RC  16 . The CP  18  further includes output circuitry  86  (e.g., via the telemetry circuitry of the RC  16 ) for downloading stimulation parameters to the IPG  14  and RC  16  and for uploading stimulation parameters already stored in the memory  66  of the RC  16 , via the telemetry circuitry  68  of the RC  16 . 
     Execution of the programming package  84  by the control circuitry  80  provides a multitude of display screens (not shown) that can be navigated through via use of the mouse  72 . These display screens allow the clinician to, among other functions, to select or enter patient profile information (e.g., name, birth date, patient identification, physician, diagnosis, and address), enter procedure information (e.g., programming/follow-up, implant trial system, implant IPG, implant IPG and lead(s), replace IPG, replace IPG and leads, replace or revise leads, explant, etc.), generate a pain map of the patient, define the configuration and orientation of the leads, initiate and control the electrical stimulation energy output by the neurostimulation leads  12 , and select and program the IPG  14  with stimulation parameters in both a surgical setting and a clinical setting. Further details discussing the above-described CP functions are disclosed in U.S. patent application Ser. No. 12/501,282, entitled “System and Method for Converting Tissue Stimulation Programs in a Format Usable by an Electrical Current Steering Navigator,” and U.S. patent application Ser. No. 12/614,942, entitled “System and Method for Determining Appropriate Steering Tables for Distributing Stimulation Energy Among Multiple Neurostimulation Electrodes,” which are expressly incorporated herein by reference. 
     Most pertinent to the present inventions, programming of the IPG  14  can be performed based on a user-defined lead configuration corresponding to the actual configuration in which the neurostimulation leads  12  are physically implanted within the patient. This lead configuration is graphically displayed in the context of an anatomical region, and in this case, the spinal column of the patient. Preferably, the lead configuration is defined by the user to correspond with the actual configuration of the neurostimulation leads  12  within the patient, which can be obtained using suitable means, such as viewing a fluoroscopic image of the neurostimulation leads  12  and surrounding tissue of the patient, or using electrical means, such as transmitting electrical signals between the electrodes carried by the respective leads and measuring electrical parameters in response to the electrical signals, such as, e.g., any one or more of the manners disclosed in U.S. Pat. No. 6,993,384, entitled “Apparatus and Method for Determining the Relative Position and Orientation of Neurostimulation Leads,” U.S. patent application Ser. No. 12/550,136, entitled “Method and Apparatus for Determining Relative Positioning Between Neurostimulation Leads,” and U.S. patent application Ser. No. 12/623,976, entitled “Method and Apparatus for Determining Relative Positioning Between Neurostimulation Leads,” which are expressly incorporated herein by reference. 
     Significantly, graphical representations of the neurostimulation leads  12  are displayed in the context of a composite graphical representation of the spinal column of the patient, comprising a global graphical representation of the spinal column and a local graphical representation of a portion of the spinal column. A view finder is displayed over a portion of the global graphical spinal column representation, such that the portion of the local graphical spinal column representation corresponds to the portion of the global graphical spinal column representation over which the view finder is displayed. The displayed view finder may be modified (e.g., by changing a position and/or size) to define a different portion of the global graphical spinal column representation, and the local graphical spinal column representation automatically updated to reflect the portion of the global graphical spinal column representation currently defined by the view finder. In this manner, the entirety of the spinal column work area may be quickly established and easily navigated using the global graphical representation, while allowing instant assessment of the location and programming status of the neurostimulation leads  12  using the local graphical representation. 
     As one example, and with reference to  FIG. 7 , a lead configuration screen  100  illustrating a graphical representation of an adjustable lead configuration (in this case, consisting of three graphical lead representations  12 ′) can be manipulated by the user to define the lead configuration that best matches the actual configuration of the neurostimulation leads  12 . In the illustrated embodiment, the lead configuration screen  100  is segmented into a lead type selection section  100   a  displaying a plurality of lead generation icons  102   a - 102   d , a global view section  100   b  displaying a global graphical representation of the spinal column  42 ′, and a local view section  100   c  displaying a local graphical representation of the spinal column  42 ′. 
     In this embodiment, the graphical lead representations  12 ′ are displayed in a staggered arrangement that presumably matches the side-by-side arrangement of the actual leads  12  implanted in the patient. The graphical lead representations  12 ′ are illustrated as being superimposed over a composite graphical representation of spinal column  42  at locations matching the location of the spinal column  42  at which the actual leads  12  are implanted. The composite graphical representation of the spinal column  42  consists of the global graphical spinal column representation  42 ′ and the local graphical spinal column representation  42 ″. 
     In order to define the lead configuration, objects can be dragged and dropped from a selected one of a plurality of lead generation icons  102   a - d  to generate the graphical lead representations  12 ′. As example, the lead generation icons include 1×8 percutaneous lead generation icon  102   a , a 1×16 percutaneous lead  102   b , a 2×8 paddle lead  102   c , and a 4×8 paddle lead  102   d . The location of the graphical lead representations  12  relative to the global and local graphical spinal columns  42 ′,  42 ″, as well as the longitudinal distance and/or lateral distance between the graphical lead representations  12 ′, can be defined in this manner. In the illustrated embodiment, objects are dragged and dropped from the 1×8 percutaneous lead generation icon  104   a  to create a lead configuration consisting of three virtual 1×8 percutaneous leads  12   a ′,  12   b ,  12   c ′. The control circuitry  80  of the CP  18  allows the user to graphically create new lead configurations from the initial lead configuration by allowing the user to select one of the graphical lead representations  12 ′ (e.g., by coupling to one of the graphical lead representations  12 ′), dragging the selected graphical lead representation  12 ′ (e.g., by displacing the selected graphical lead representation  12 ′ relative to the other graphical lead representation  12 ′), and dropping the displaced graphical lead representation  12 ′ (e.g., by decoupling from the displaced graphical lead representation  12 ′). The object can either be dropped into the global view section  100   b  to define a graphical lead representation  12  relative to the global graphical spinal column  42 ′ (in which case, the local view section  100   c  will be automatically updated with the graphical lead representation  12 ′) or dropped into the local view section  100   c  to define a graphical lead representation  12  relative to the local graphical spinal column representation  42 ″ (in which case, the global view section  100   b  will be automatically updated with the graphical lead representation  12 ′). 
     The manner in which a graphical lead representation  12 ′ is selected, dragged, and dropped will depend on the nature of the user interface. For example, if the display screen  76  is conventional, a virtual pointing device (e.g., cursor controlled by the mouse  72 , joy stick, trackball, etc.) can be used to select, drag, and drop the graphical lead representations  12 ′ into the global or local view sections  100   b ,  100   c . If the display screen  76  is a digitizer screen, a physical pointing device (e.g., a stylus or finger) can be used to select, drag, and drop the graphical lead representations  12 ′ into the global or local view sections  100   b ,  100   c . Further details discussing the generation of lead configurations using a drag and drop technique are set forth in U.S. Provisional Patent Application Ser. No. 61/333,673, entitled “System and Method for Defining Neurostimulation Lead Configurations,” which is expressly incorporated herein by reference. 
     As briefly discussed above, a view finder  104  is displayed over a portion of the global graphical spinal column representation  42 ′. In the illustrated embodiment, the view finder  104  takes the form of a box outline. Alternatively, the view finder  104  may take the form of other shapes, such as a circle outline. In the case illustrated in  FIG. 7 , the portion of the global graphical spinal column representation  42 ′ over which the view finder  104  is displayed consists of the T7-T10 vertebral segments, and thus, the displayed local graphical spinal column representation  42 ″ consists of the T7-T10 vertebral segments (including the entire graphical lead representations  12   b  and  12   c ). 
     The displayed view finder  104  may be displaced (and in this case, scrolled longitudinally along the global graphical spinal column representation  42 ′) to another different portion of the global graphical spinal column representation  42 ′, such that at least one of the graphical lead representations  12 ′ is displayed in the local graphical representation of the other portion of the spinal column  42 ″. Thus, as the view finder  104  is scrolled along the global graphical spinal column representation  42 ′, the local graphical spinal column representation  42 ″ will automatically update to reflect the portion of the global graphical spinal column representation  42 ″ spatially defined by the view finder  104 . 
     For example, as illustrated in  FIG. 8 , the different portion of the global graphical spinal column representation  42 ′ over which the view finder  104  is displayed consists of the T1-T5 vertebral segments (including graphical lead representation  12   a ). In the illustrated embodiment, displacement of the view finder  104  is limited to one axis along the spinal column. In an optional embodiment, the view finder  104  may be displaced in the lateral direction (left and right), in addition to the longitudinal direction (up and down), thereby allowing the view finder  104  to be displaced in two dimensions. 
     The lead configuration screen  100  includes different control elements for displacing the view finder  104 . For example, the view finder  104  may, itself, serve as a graphical control element. If the display screen  76  is conventional, the user may click on the view finder  104  using a virtual pointing device in the form of a graphical cursor  106  (shown as a hand) via a mouse  72  or other pointing device, and drag the view finder  104  to a different portion of the global graphical spinal column representation  42 ″. If the display screen  76  is a digitizer screen, the user may place a physical pointing device adjacent the view finder  104  and draft the view finder  104  to a different portion of the global graphical spinal column representation  42 ″. In the illustrated embodiment, the outline of the view finder  104  or any graphical space contained in the outline may be manipulated by the pointing device to displace the view finder  104 . 
     Alternatively, the graphical control element may be completely separate from the view finder  104 . For example, the graphical control element can take the form of a graphical slider bar  108 , which in the exemplary lead configuration screen  100 , is adjacent the local graphical spinal column representation  42 ′. The graphical slider bar  108  can be moved up or down using, e.g., a pointing device (not shown), to thereby scroll the view finder  104  longitudinally along the global graphical spinal column representation  42 ″. As the view finder  104  is scrolled along the global graphical spinal column representation  42 ″, the local graphical spinal column representation  42 ″ will automatically update to reflect the portion of the global graphical spinal column representation  42 ″ within the view finder  104 . 
     In other embodiments, the control element may be simply be distributed on the local graphical spinal column representation  42 ′ and surrounding area on the display screen  100 . That is, any area in the local view section  100   c  can be manipulated (e.g., clicked or touched) using, e.g., a pointing device (not shown), to thereby scroll the view finder  104  longitudinally along the global graphical spinal column representation  42 ″. Again, as the view finder  104  is scrolled along the global graphical spinal column representation  42 ″, the local graphical spinal column representation  42 ″ will automatically update to reflect the portion of the global graphical spinal column representation  42 ″ within the view finder  104 . 
     In an optional embodiment, the individual vertebral segments (or the vertebral segment labels) of the global graphical spinal column representation  42 ″ the individual lead representations  12 ′ displayed on the global view section  100   b  may serve as graphical control elements. For example, any of the vertebral segments or lead representations can be clicked or otherwise touched, such that the view finder  104  is automatically centered on the vertebral segment or lead representation that is clicked or touched. For example, if any portion of the vertebral segment T7 is clicked or touched, the view finder  104  may be automatically centered on the vertebral segment T7, such that the center of the vertebral segment T7 coincides with the center of the view finder  104  in the global view section  100   b , and therefore, is centered in the local view section  100   c . Similarly, if any portion of the graphical lead representation  12   b  is clicked or touched, the view finder  104  may be automatically centered on the graphical lead representation  12   b , such that the center of the graphical lead representation  12   b  coincides with the center of the view finder  104  in the global view section  100   b , and therefore, is centered in the local view section  100   c . In still another optional embodiment, if the control element may be distributed on the graphical view section  100   b , such that any point that is clicked or touched on the graphical view section  100   b  will prompt the view finder  104  to be centered on that point. 
     In addition to being displaced, the size of the displayed view finder  104  may optionally be changed; for example, expanded or contracted, such that the size of the local graphical spinal column representation  42 ″ is correspondingly changed. The lead configuration screen  100  may include different control elements for displacing the view finder  104 . For example, as shown in  FIGS. 9 and 10 , control elements may take the form of upper and lower handles  110   a ,  110   b  respectively extending from the top and bottom borders of the view finder  104 . Either of the handles  110  can be dragged using a pointing device (not shown) to expand or contact the view finder  104  in the upward or downward direction. For example, the upper handle  110   a  may be dragged upward to correspondingly expand the view finder  104  in the upward direction, as shown in  FIG. 9 , or the upper handle  110   a  may be dragged downward to correspondingly contract the view finder  104  in the downward direction, as shown in  FIG. 10 . It can be appreciated that the lower handle  110   b  may be also dragged downward to correspondingly expand the view finder  104  in the downward direction, or the lower handle  110   b  may also be dragged upward to corresponding contract the view finder  104  in the upward direction. Optionally, left and right handles (not shown) can respectively extend from the left and right borders of the view finder  104 . In this case, these handles may be dragged leftward or rightward to expand or contract the view finder  104  in the left or right directions. 
     As the view finder  100  is expanded or contracted, the local graphical spinal column representation  42 ″ will automatically update to reflect the expanded or contracted portion of the global graphical spinal column representation  42 ″ within the view finder  104 . In the case illustrated in  FIG. 9 , the portion of the global graphical spinal column representation  42 ′ over which the view finder  104  is displayed is expanded to consist of the T2-T11 vertebral segments, and thus, the displayed local graphical spinal column representation  42 ″ is expanded to consist of the T2-T11 vertebral segments (including the entirety of all of the graphical lead representations  12 ). In the case illustrated in  FIG. 10 , the portion of the global graphical spinal column representation  42 ′ over which the view finder  104  is displayed is contracted to consist of the T9-T11 vertebral segments, and thus, the displayed local graphical spinal column representation  42 ″ is contracted to consist of the T9-T11 vertebral segments (including only the graphical lead representation  12   c ). 
     In alternative embodiments, the borders of the view finder  104 , themselves, can be used as control elements that can be dragged to correspondingly expand or contract the view finder  104 . In this case, the borders of the view finder  104  cannot be used to displace the view finder  104  in the manner discussed above with respect to  FIGS. 7 and 8 . Instead, the pointing device may be placed adjacent the interior of the view finder  104  to displace it. 
     Once the lead configuration is established in the lead configuration screen  100 , a different display screen can be accessed to program the neurostimulation leads  12  with the desired stimulation parameters, e.g., in the manner described in U.S. patent application Ser. No. 12/501,282, which has been previously incorporated herein by reference. 
     Although the foregoing technique has been described as being implemented in the CP  18 , it should be noted that this technique may be alternatively or additionally implemented in the RC  16 . Furthermore, although particular embodiments of the present inventions have been shown and described, it will be understood that it is not intended to limit the present inventions to the preferred embodiments, and it will be obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present inventions. Thus, the present inventions are intended to cover alternatives, modifications, and equivalents, which may be included within the spirit and scope of the present inventions as defined by the claims.