RELATED APPLICATIONS 
   This application is a divisional of U.S. patent application, Ser. No. 09/587,673 filed Jun. 5, 2000 entitled: “Neuromodulation Therpy System and Method”. Application Ser. No. 09/587,673, which issued on Jun. 8, 2004 as U.S. Pat. No. 6,748,276, is hereby incorporated herein by reference. 


   FIELD OF THE INVENTION 
   The present invention relates to a system that is capable of storing multiple data sets, which are not otherwise identifiable but for individual execution of such data sets; however, the system includes a display mechanism to display certain visual imagery to enable the functionality of each data sets to be distinguished. 
   BACKGROUND OF THE INVENTION 
   Application of specific electrical fields to spinal nerve roots, the spinal cord, and/or other nerve bundles for the purpose of chronic pain management has been actively practiced since the 1960s. While a precise understanding of the interaction between the applied electrical energy and the nervous tissue is not fully appreciated, it is known that application of an electrical field to spinal nervous tissue (i.e., spinal nerve roots and spinal cord bundles) can effectively interfere with the transmission of certain pain signals through such nervous tissue. More specifically, applying particularized electrical pulses to spinal nervous tissue that corresponds to regions of the body afflicted with chronic pain can induce paresthesia, or a subjective sensation of numbness or tingling, in the pain-afflicted regions. Depending on the individual patient, paresthesia can effectively “mask” certain pain sensations to the brain. 
   The above description uses the term “particularized” to denote that the applied electrical energy is intended to be focused on the specific spinal nervous tissue associated with the afflicted bodily regions. Care should be taken to avoid over stimulating the targeted nervous tissue, as over stimulation could lead to paresthesia being perceived in non-afflicted regions or, alternatively, feelings of discomfort. 
   As a first step to delivering effective electrical energy to targeted nervous tissue, the source of the electrical energy must be positioned proximate to such nervous tissue. Electrical energy is commonly delivered through conductive electrodes positioned external to a patient&#39;s dura layer, a structure that surrounds the spinal cord. Electrodes are carried by two primary vehicles: the percutaneous catheter and the laminotomy lead. Percutaneous catheters and laminotomy leads will be collectively referred to as “stimulation leads.” 
   Percutaneous catheters, or percutaneous leads, commonly have two or more electrodes (for example, two, four, and eight) and are positioned above the dura layer through the use of a Touhy-like needle that passes through the skin, between desired vertebrae, and opens above the dura layer. Laminotomy leads have a thin paddle configuration and typically possess a plurality of electrodes (for example, two, four, eight, or sixteen) arranged in one or more columns. Surgical intervention is required for implanting laminotomy leads. In particular, a partial laminectomy is required, which involves the resection and removal of certain vertebral tissue to allow both access to the dura and proper positioning of the laminotomy lead. 
   Assuming that physical placement of the electrical energy source can be achieved, specific “selection” of the targeted nervous tissue from an encompassing tissue bundle is achieved through refinement of the delivered electrical energy. To this end, the delivered electrical energy is defined by an electrode configuration and an electric pulse waveform, or collectively a “stimulation setting.” 
   The overall form of the delivered electrical energy is defined by the polarity of each electrode of the stimulation lead. With modern stimulation systems, each electrode can assume a positive polarity (an anode), a negative polarity (a cathode), or an off-state. The collective definition of the polarities of each electrode of a stimulation lead is described as an “electrode configuration.” 
   The electric pulse waveform defines the nature of the signal delivered through the active electrodes. Of course, an electric pulse waveform is defined by a plurality of variables, including: pulse width (μs) (i.e., the duration in which the pulse is in a high state), frequency (Hz), amplitude (V), and sometimes phase (i.e., mono-phasic or bi-phasic). For purposes of description, a collection of these variables to define a single waveform will be referred to as a “treatment parameter set.” 
   Identifying an optimum stimulation setting-one that masks a maximum quantity of pain with minimum over stimulation-can be time consuming and difficult. In particular, not even considering the endless combinations that can be effected by modifying the variables of a treatment parameter set, an eight-electrode stimulation lead offers 6,050 possible electrode combinations. 
   As may be understood from the above description, a single stimulation setting corresponds to a single treatment parameter set and a single electrode configuration. Consequently, each stimulation setting typically addresses only a single localized region of the body. If a patient experiences complex pain (i.e., pain that extends across multiple or varied regions of the body), then multiple stimulation settings may be required to address such pain. Further yet, different stimulation settings may be required for different times of the day or for different activities within the day, whereas changes in body position (e.g., lying down, sitting, standing) may impair or alter the effectiveness of any one stimulation setting. 
     FIG. 1  illustrates a modern, radio frequency (RF) stimulation system  1000 . In particular, the system  1000  includes an external transmitter  1002  that is connected to an antenna  1004 . Internally, a receiver  1008  is connected to at least one stimulation lead  1010  (and  1012 ), which in this instance is illustrated having eight electrodes  1010   a–h  (and  1012   a–h  for stimulation lead  1012 ). The receiver  1008  Bib communicates, via an antenna  1006 , with the transmitter  1002  through the skin  1032  of a patient. 
   Stimulation settings are stored within a memory of the transmitter  1002 . Stimulation settings can be programmed into the transmitter  1002  using transmitter-based controls (not shown) or using a computer  1028  (e.g., U.S. Pat. No. 5,938,690 to Law et al.) through a removable connection  1030 . operatively, stimulation settings are imposed on a RF carrier signal and passed to the receiver  1008  through the skin  1032  to effect stimulation through electrodes  1010   a–h  and  1012   a–h.    
   The system  1000  allows the storage and application of 1–24 stimulation settings. Each stimulation setting is numerically represented (i.e., “1”, “2”, “3”, etc.) based on an order of input into the transmitter  1002 . The transmitter  1002  executes all stored stimulation settings sequentially, based on the settings respective numerical representations. The execution of “adjacent” stimulation settings is made within a fixed time interval, such interval being of such a duration that switching between adjacent stimulation settings is largely imperceivable to the patient. 
   To this end, the conventional system would enable up to 24 different pain areas to be addressed. However, short of reprogramming the stored stimulation settings, this system does not readily allow changes in stimulation settings for changes in activities or patient posture. Moreover, with each stimulation setting being simply represented by an alphanumeric representation, a patient or practitioner must maintain a separate log that correlates each stimulation setting with its stimulation effect. Otherwise, the patient would be required to execute each stored stimulation setting to appreciate its consequence. 
   Accordingly, a need exists for a stimulation system that provides a user substantive information regarding the effects or intended application of a stored stimulation setting. 
   A further need exists for a stimulation system that allows stored stimulation settings to be both readily and arbitrarily grouped, whereas each stimulation setting of a group is directed to addressing a common condition, and multiple groups are available for execution. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to overcome the known limitations of current neuromodulation systems described above. 
   Another object of the present invention is to provide a display mechanism for a user-portion of a neuromodulation system that conveys graphical information to a user regarding the intended effect of a stimulation setting. 
   To this end, one aspect of the present invention is directed to a tissue stimulation system having a transmitter, a receiver for implantation within a patient, and at least one multi-electrode, implantable stimulation lead. The stimulation lead is electrically connectable to the receiver. The transmitter is adapted to transmit stimulation data to the receiver, which effects delivery of electrical energy through the connected stimulation lead. Importantly, the delivered electrical energy is defined by stimulation setting(s). 
   Unlike known systems, the system of this aspect includes a memory adapted to store at least two programs, each program including a plurality of stimulation settings, a selector, and a controller. The selector operatively effects a selection of a stored program. The controller executes any selected programs, such involving the conversion of a stimulation setting of the selected program to stimulation data for transmission to the receiver. 
   For a neuromodulation system having a memory to store a plurality of independent instructions to effect an equal number of stimulation profiles, another aspect of the present invention is directed to a method for providing an identifier to enable a visual recognition of a functionality of each instruction. The steps for such provision include creating an instruction data file, which includes a plurality of variables that operatively defines a therapeutic application, to effect a stimulation profile when executed; and generating a graphical anatomical representation that effectively depicts a perceived stimulation profile. From this action, the anatomical representation is assessed so to generate a representative graphical image. With such image, the instruction data file is modified to include data corresponding to such representative graphical image. 
   Other objects and advantages of the present invention will be apparent to those of ordinary skill in the art having reference to the following Specification together with the drawings. 


   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring now to the drawings in which like reference numerals and letters indicate corresponding elements throughout the several view, if applicable: 
       FIG. 1  is a schematic representation of a conventional radio-frequency neuromodulation system; 
       FIG. 2  is a schematic representation of a radio-frequency neuromodulation system in accordance with the present invention; 
       FIG. 3  illustrates a radio-frequency transmitter for use in the system of  FIG. 2 ; 
       FIG. 4  schematically illustrates both a program data file and a stimulation setting data file operatively stored within the transmitter of  FIG. 3 ; 
       FIG. 5  illustrates one possible display arrangement presentable on a display of the transmitter of  FIG. 3 ; 
       FIG. 6  illustrates another possible display arrangement presentable on the display of the transmitter of  FIG. 3 ; 
       FIGS. 7A through 7D  illustrate various display arrangements presentable on the display of the transmitter of  FIG. 3  in a program selection mode; 
       FIG. 8  schematically illustrates a database structure employed by software subject to execution by a computer of the system of  FIG. 2 ; 
       FIGS. 9A through 9E  illustrate various screen shots from software (subject to execution by a computer of the system of  FIG. 2 ) and related transmitter displays, that operatively relate to the identification, setting, selection, and downloading of one or stimulation programs; 
       FIG. 10  illustrates anterior and posterior views of a bodily image graphic displayed by software subject to execution by a computer of the system of  FIG. 2 ; 
       FIG. 11  illustrates a composite bodily graphic presentable on the display of the transmitter of  FIG. 3 , which is visually formed from data of the anterior and posterior views of the bodily image graphic of  FIG. 10 ; 
       FIG. 12  partially illustrates a conversion table that includes data that establishes a graphical relationship among the display of the transmitter of  FIG. 3 , the composite bodily graphic of  FIG. 11 , and the anterior view of the bodily image graphic of  FIG. 10 ; 
       FIG. 13  partially illustrates a conversion table that includes data that establishes a graphical relationship among the display of the transmitter of  FIG. 3 , the composite bodily graphic of  FIG. 11 , and the posterior view of the bodily image graphic of  FIG. 10 ; 
       FIG. 14  is a flow chart algorithm for the storage of image-related data that comprises the anterior and posterior views of the bodily image graphic of  FIG. 10 ; 
       FIG. 15  is a flow chart algorithm for graphical image conversion from the anterior and posterior views of the bodily image graphic of  FIG. 10  to the composite bodily graphic of  FIG. 11 ; and 
       FIGS. 16A and 16B  illustrate alternative methods of delivering multiple stimulation settings. 
   


   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Various embodiments, including preferred embodiments, will now be described in detail below with reference to the drawings. 
     FIG. 2  illustrates one embodiment of a system in accordance with the present invention. The system  100  includes an external transmitter  102  that is connected to an antenna  104 . Internally, a receiver  108  is connected to at least one stimulation lead  110  (and  112 ), which in this instance is illustrated having eight electrodes  110   a–h  (and  112   a–h  for stimulation lead  112 ). The receiver  108  communicates, via an antenna, 106 , with the transmitter  102  through the skin  120  of a patient. While the receiver  108  can include an internalized power source, it is more likely that the receiver  108  is powered by the carrier wave transmitted by the transmitter  102 . 
   The computer  128  is a general-purpose computer that includes executable software. The computer  128  is capable of receiving input via its display (i.e., touch screen) or through a mouse or a stylus (not shown). While not critical to the invention, the computer  128  preferably operates in a Windows™-based environment. The computer  128  should include, or otherwise be connectable to, a display (or other output device) having a sufficient resolution so as to clearly preset the visual information required by the present invention, such information being discussed in greater detail below. 
   The computer  128  is connectable to the transmitter  102  through a cable  130 . In particular, it is preferable that the cables  130  extend between a standard RS232 serial port of the computer  128  and a serial connector (not shown) on the transmitter  102 . Alternatively, the computer  128  and the g transmitter  102  could be “connected” using an infrared transmission, a radio-frequency transmission, or an ultrasonic transmission. 
   The communication protocol used between the computer  128  and the transmitter  102  is preferably conventional, using traditional message blocks. Such message blocks incorporating message identification, type, data, checksum, and length fields. Component responses to data transmissions are likewise traditional, i.e., using ACK and NACK signals. 
     FIG. 3  illustrates one embodiment of the transmitter  102 . The transmitter includes a display  50 . In a preferred embodiment, the display  50  has a resolution that allows alphanumeric and limited graphics data to be displayed, whether in monochrome or in color. In a preferred embodiment, the display  50  is 100 column×32 row, monochrome LCD. While the specific controls are not necessarily critical to the invention, such will be at least mentioned here for reference. 
   User controls  52  and  54  function to respectively decrease and increase certain definable variables, e.g., stimulation amplitude. User control  56  functions to “cancel” an input or screen selection. User controls  58  and  60  are scroll controls, to enable a user to scroll through various presented options. User control  62  is an “enter” key, wherein inputs or options are selectable through actuation of user control  62 . User control  64  is a “balance” key, which enables individual amplitude adjustment for each available stimulation setting of a program, its use will be discussed further below. Finally, user control  66  is a power switch. 
   The transmitter  102  functions to receive and store one or more stimulation settings. Stimulation settings can be entered or modified through the user controls  52 ,  54 , and  58 - 64  and/or through the connected computer  128 . Stimulation settings are stored in a non-volatile memory  68 . Memory  68  requires a capacity sufficient to store a prescribed number of programs, and each program can include multiple stimulation settings. In a preferred embodiment, the transmitter  102  can operatively maintain at least two programs, each program including at least two stimulation settings. 
   In a more preferred embodiment, the transmitter  102  can operatively maintain more than ten programs, each program maintaining no more than ten stimulation settings. In a most preferred embodiment, the transmitter  102  can operatively maintain twenty-four programs, and each program can maintains eight stimulation settings. 
     FIG. 4  illustrates a program data file as maintained in the transmitter. 102 , and more particularly, within the memory  68 . The program data file includes space for a program number, a quantity of stimulation settings within the program, composite graphic data, and a maximum number of stimulation setting files. Each stimulation setting data file includes space for a program number, a stimulation setting number, a frequency value, a pulse width value, an electrode configuration (to define the state for each of the connected electrodes  110   a–h  and  112   a–h ), minimum and maximum amplitude limitations, and graphics data. 
   Operatively, for an active program, a microprocessor (not shown) within the transmitter  102  reads the memory  68  and extracts the program-specific data. The program-specific data is displayed in the display  50 . An example of such a display is shown in  FIG. 5 . 
   In reference to  FIG. 5 , region  25  indicates that program no.  8  is active, and that this program includes four stimulation settings. Region  26  depicts an overall-amplitude control adapted to control commonly an amplitude value for all stimulation settings of the active program. The overall-amplitude control is managed using user controls  52  and  54 . In region  27 , battery life indicator is provided. While the battery life indicator is shown reflecting a specific time format (i.e., hours: minutes), such indicator could also display a relative time remaining using a variably filled battery form. Lastly, region  28  includes a composite graphic, which is formed from graphics data contributed from each of the stimulation settings of the program. The “composite” bodily graphic readily conveys to a user which regions of the patient&#39;s body are addressed by the current program. In particular reference to the illustrated graphic of region  28 , program no.  8  effects stimulation in the right arm  28   a , the left arm  28   b , the right leg  28   c , and the left leg  28   d.    
   Of note, while  FIG. 5  illustrates an overall-amplitude control, the transmitter  102  also allows the amplitude of each stimulation setting to be individually modified. Accordingly, delivered energy is governed by (i) individual amplitude settings, which are confined between minimum and maximum amplitude limits as defined in the respective stimulation setting data files and (ii) the overall-amplitude control. In regard to the latter, if the overall-amplitude control is set, for example, at 30% of maximum, each stimulation setting will realize only 30% of its set amplitude.  FIG. 6  illustrates an example display that enables the individual adjustment of each of the stimulation settings of the program illustrated in  FIG. 5 . 
   In reference to  FIG. 6 , arrow  30  indicates which stimulation setting amplitude is subject to modification. Control of arrow  30  is performed by user controls  58  and  60 . Selection of a stimulation setting is effected by actuation of user control  62 . Region  29  reflects respective “slider” controls for each stimulation setting. The individual minimum value (i.e., lower position of each slider) and maximum value (i.e., upper position of each slider) is dictated by the provided minimum and maximum amplitude limits, which (as stated above) are set within the individual stimulation setting files. Gradation fineness along each slider is a function of the differential between the maximum and minimum amplitude limits. 
   The display of region  31  is a function of the position of the arrow  30 . In particular, the displayed graphic reflects the bodily region addressed by the selected stimulation setting. In this instance, the right arm  28   a  is shown (of note, this right arm representation is also a part of the composite graphic displayed in  FIG. 5 ). 
   For this particular embodiment, the display of  FIG. 6  is accessed by actuation of user control  64 . For safety purposes, it is preferred that modification of individual amplitude settings cannot occur unless the overall-amplitude is set to a low percentage value, e.g., 0%. 
   Focusing on the actual delivery of stimulation, for each stimulation setting, the microprocessor reads such stimulation setting from the active program, effects a multiplexing of the substantive data, or treatment parameter set (i.e., frequency, pulse width, phase, and electrode configuration) and a separately-stored, related amplitude value, and drives the delivery of the multiplexed data to a modulator (not shown) for preparation and combination with a generated RF carrier wave. The data-supporting carrying carrier wave is then passed to the antenna  104 , which forwards the integrated stimulation setting (i.e., electrode configuration and waveform definitional variables) and carrier wave, which represents a source of power for the receiver  108 , to the antenna  106  and the connected receiver  108 . 
   For a program having multiple stimulation settings, the microprocessor automatically cycles through each of the stimulation settings, executing each setting in a manner consistent with the above description. The microprocessor controls the time that any one stimulation setting is executed. For example, the microprocessor could define a specific period (e.g., 10 milliseconds), a period based on a frequency of the stimulation setting (e.g., two cycles, three cycles), or a combination of both (e.g., at least two cycles but not less than 10 milliseconds). Consistent with known systems, it is preferable that any time between executed stimulation settings be negligible so that a patient cannot readily perceive a transition between adjacent stimulation settings. As a further alternative, the microprocessor could execute one stimulation setting per pulse, thus creating a truly “seamless” therapy application. These alternatives are illustrated in  FIGS. 16A AND 16B . 
   Multiple programs, which include one or more stimulation settings, can be used to address the shortcomings of the current art described earlier. Specifically, the user can establish different programs to address different activities as well as different postures. When the transmitter  102  has received multiple programs, the user actuates a user control of the transmitter  102  (e.g., the user controls  58  or  60 ) to access a program selection mode (indicated by a “P” in the lower left-hand corner of the display  50 ). Upon actuation of the user control  62 , controls  58  and  60  are then used to scroll through the possible stored programs ( FIGS. 7A–7D ). Selection of any one program is effected through actuation of the user control  62 . Of note, the illustrated graphics of the regions  28  of  FIGS. 7A–7D  reflect the different stimulation option available: left and right legs (PROGRAM  2 ); upper torso (PROGRAM  3 ); left and right arms and lower back (PROGRAM  4 ); and left and right arms and left and right legs (PROGRAM  5 ). 
   While the above discussion has focused on the user-portion of the present invention, the following discussion will be particularly directed to the software that is executed by the computer  128 . In a general sense, the software offers the following features:
         patient entry and identification;   real-time definition and testing of stimulation parameters;   documentation of tested stimulation results via graphical stimulation map(s);   storage of tested parameters, including graphical stimulation map(s);   review and selection of tests results for therapy definition;   conversion of graphical stimulation map(s) for use by the user device (e.g., transmitter  102 ); and   download of defined therapies to the user device.
 
Additional features of the software include those also identified in co-pending U.S. patent application Ser. No. 09/587,673, filed Jun. 5, 2000, such disclosure being incorporated by reference herein.
       

   Of the features above, “patient entry and identification” concerns the interface and record-keeping processes to manage the records stored within the computer  128 . Reference is hereby made to  FIG. 8 , which illustrates the database structure used by the software. As can be seen in this figure, each record is indexed by a patient identification (e.g., a patient name), and in many instances, the patient&#39;s physician for verification. The PATIENTS and PHYSN tables  70  and  72  cooperate to maintain various, common identification and personal information, including: a patient name, physician, address, date of birth, etc. The means used to obtain this information, and even the information itself, is not essential to the present invention, excepting its role as a basis to establish an effective relational database. 
   In continued reference to  FIG. 8 , the lines and arrows connecting the various tables illustrate a preferred structure that establishes relationships and avoids duplication of data. Relationships between database tables are designated by a“*”. Moreover, as a further example of this reduction in storage overhead, the TESTRES table  80  is used for both storage of tests and program definition. When considering the relational dependency of the STIMMAP table  82 , there is need for only one stimulation image for every test (i.e., stimulation setting). While the present system could provide for multiple images (or the data representative of multiple images) to be recorded for each stimulation setting, at least this embodiment does not incorporate such variation. Thus, there is a one-to-one correspondence between each test result entry and the STIMMAP table  82 . 
   Real-Time Definition and Testing of Stimulation Parameters 
   In explaining the process of real-time definition and testing of stimulation parameters, reference will be made to the screen shot of the software reproduced in  FIG. 9A . The illustrated screen is the “stimulation parameter adjustment and testing screen.” To define a stimulation parameter, the following steps are followed: 
   Step #1: With an amplitude set to 0 V (Field  206 ), a practitioner defines an electrode configuration (Field  200 ), a frequency value (Field  202 ), and a pulse width value (Field  204 ). 
   Step #2: The amplitude “slider” (Field  205 ) is adjusted, and a patient response is recorded at the amplitude where stimulation is first perceived using screen button  208   a.    
   Step #3: The practitioner highlights all regions of the stimulation image (Region  210 ) that correspond to the actual perceived stimulation experienced by the patient. Of note, the stimulation diagram initially begins as only a bodily outline having a plurality of demarcated, non-highlighted regions ( FIG. 10 ). 
   Step #4: The amplitude slider (Field  205 ) is again adjusted, and a patient response is recorded at the amplitude where bilateral stimulation is first perceived using screen button  208   b.    
   Step #5: The practitioner highlights all regions of the stimulation image (Region  210 ) that correspond to the perceived feeling of the patient at such bilateral perception. Highlighting regions previously highlighted in Step #3 will result in such regions being updated with a bilateral-related value. 
   Step #6: The amplitude slider (Field  205 ) is again adjusted, and a patient response is recorded at the amplitude where maximum stimulation is first perceived using screen button  208   c . Maximum stimulation is usually determined by the invocation of involuntary muscle reaction or other conditions that are equally undesirable. 
   Step #7: The practitioner highlights all regions of the stimulation image (Region  210 ) that correspond to the perceived feeling of the patient at motor perception. Highlighting regions previously highlighted in Steps #3 or Steps #5 will result in such regions being updated with a motor-related value. 
   Step #8: The defined stimulation parameters and related stimulation image is saved by actuating the “log setting” screen button (Region  212 ). The corresponding treatment parameter set is stored in portion  80  of TESTRES table  78  (Step S 102  of  FIG. 14 , discussed hereinbelow), and data representative of the stimulation image are stored in portions  86  and  88  of STIMMAP table  82  (Steps S 108  and S 114  of  FIG. 14 , discussed hereinbelow). The stimulation image is preferably stored on a region-by-region basis and can be represented by binary data or an analog data. While not preferable, the image as a whole (i.e., a bitmap) could be stored. For each region of pain or variation in posture that may require a different stimulation setting, Steps 1–8 are repeated to obtain the necessary number of treatment parameter sets. 
   From the perception, bilateral, and motor amplitude values entered in the above steps, the software defines a minimum amplitude value and a maximum amplitude value for the corresponding stimulation setting. As shown in  FIG. 4 , these values are stored in each stimulation setting data file. While not within the scope of this disclosure, the software can further use the perception, bilateral, and motor amplitude values to calculate an initial stimulation amplitude, or a comfort amplitude. As but one example, the comfort amplitude is equivalent to the perception amplitude plus an incremental value, such incremental value being based on the bilateral and the motor amplitude values (e.g., 60% of a difference between the motor amplitude value and the bilateral value). The comfort amplitude can be downloaded and stored in association with a corresponding treatment parameter set. 
   Further, as may be appreciated, the individual and composite stimulation graphics displayed on the display  50  of the transmitter  102  (see  FIGS. 5 ,  6 , and  7 A–D) are derived from the stimulation images generated in the Steps #3, #5, and #7 described above (e.g., 40→40′ and 42→42′ in  FIGS. 10 and 11 ). As the image of the computer-based images possess significantly greater resolution, however, these images must be reduced to correspond to the display  50  of the transmitter  102 . However, as the stimulation image to be displayed on the transmitter  102  is intended to convey valuable information to a user concerning the effect of a stored, corresponding stimulation setting (i.e., an accurate representation of the stimulation images from the definition and testing session(s)), it is important that the conversion process not vitiate the significance of the data being converted. 
   For a description of the conversion process, reference will be made to FIGS.  9 A and  10 – 15 . 
     FIGS. 12 and 13  illustrate graphic conversion tables that provide a “road map” to effecting a graphical conversion from the graphical platform of the computer  128  to the graphical platform of the transmitter  102 . The content of the conversion tables is a direct function of the display  50  and its display matrix. 
   As background for some of the numerical entries in the tables of  FIGS. 12 and 13 , the display  50  used in this example requires input command signals of a 1 byte form. Each byte represents a vertical column of eight pixels. Either a pixel is “on” or “off” based on the defining bits of each byte. Conventionally, “0” represents an off-state, and “1” represents an on-state. Further to the characteristics of the display  50 , which is said to a 100 column by 32 row field for purposes of this description, addressing a particular column is made by particular reference to  1 – 100 ; however, addressing a particular row is achieved through “page” references. For example, “page 1” is the top page, or rows  1 – 8  of the display  50 ; “page 2” represents rows  9 – 16  of the display  50 ; “page 3” represents rows  17 – 24  of the display  50 ; and “page 4” is the bottom page, or rows  25 – 32  of the display  50 . Moreover, the display related transfer protocol requires that for each “page,” two image-forming instructions must be transferred-one instruction for the right side of the image, and one instruction for the left side of the image. 
   In view of these protocol-established boundaries of this exemplary embodiment, the following meanings  10  can be imparted to the headings of the tables of  FIGS. 11 and 12 .  FIG. 12  concerns ANTERIOR image regions, and  FIG. 13  concerns POSTERIOR image regions. 
   Column 1: Region numbers that directly correspond to the regions of the stimulation images displayed on the computer  128  ( FIG. 10 ). 
   Column 2: Anatomical description of each region. 
   Column 3: A value (0–3) that corresponds to the LCD positional “page” reference, described hereinabove. 
   Column 4: A value (1–20) that corresponds to a pixel column of the left portion of the image. When executed by the transmitter  102 , an offset is applied to the value to allow the image to be properly positioned within the display  50 . 
   Column 5: Decimal equivalent of the hexadecimal byte used to define a pixel representation for the left portion of the image being converted. 
   Column 6: A value (1–20) that corresponds to a pixel column of the right portion of the image. When executed by the transmitter  102 , an offset is applied to the value to allow the image to be properly positioned within the display  50 . 
   Column 7: Decimal equivalent of the hexadecimal byte used to define a pixel representation for the right portion of the image being converted. 
   Each conversion table sets forth an entry for each of the regions shown in the stimulation images (see  FIGS. 10 ,  12 , and  13 ). Notably, where left regions (and right regions) are converted and do not share pixel boundaries with another region, the Column 2 bit mask is set to zero. This allows the relevant left areas (and relevant right areas) to be masked appropriately without adding additional complexity to either the conversion tables or the controlling software. As may also be observed from the conversion tables, there is no provision for the conversion and transfer of the bodily representation displayed on the display  50 . To avoid unnecessary data transfer, preferably such bodily representation is maintained in the transmitter  102 , and thus is not contained in the converted data, or serial message. 
   In cooperation with the description of Step #8 for the process of real-time definition and testing described above,  FIGS. 14 and 15  illustrate an algorithm to effect the conversion from the stimulation images of the computer  128  to the composite bodily image for the transmitter  102 . 
   Upon actuating the “log setting” screen button (Region  212  of  FIG. 9A ; Step #8 of the process for real-time definition and testing), Step S 100  initializes a database record in TESTRES and STIMMAP tables  78  and  82  ( FIG. 8 ). In Step S 102 , the userset treatment parameter set is stored in portion  80  of TESTRES table  78 . In Step S 104 , twenty image bytes, for each of the four display pages of the display  50 , are initialized as Page1Bytes, Page2Bytes, Page3Bytes, Page4Bytes. Prior to the actual storage activities, the Area_Number variable is reset in Step S 105 . 
   The first of several decisions for this algorithm is made at Step S 106 . In particular, a specific region (i.e., Region Area_Number) of the anterior stimulation image, from Region  210  of the computer  128  (also  FIG. 10 ), is analyzed to determine whether such region is highlighted. If the decision returns a “yes,” the amplitude level for such region is stored in portion  86  of the STIMMAP table  82 , and this region is subjected to a graphical conversion using the subroutine of  FIG. 15  (described in detail below). 
   Upon concluding Step S 110  (or receiving a “no” decision from Step S 106 ), a determination is made whether the corresponding region of the posterior stimulation image, from the computer  128  ( FIG. 10 ), is highlighted. If the decision returns a “yes,” the amplitude level for such region is stored in portion  88  of the STIMMAP table  82 , and this region is subjected to a graphical conversion also using the subroutine of  FIG. 15 . 
   After conclusion of Step S 116  (or receiving a “no” decision from Step S 112 ), an inquiry is made whether the last region of both the stimulation images has been considered (Step S 118 ). If not (“no” in Step S 118 ), the Area 13  Number variable is increased by one (Step S 122 ), and the routine returns to the decision of Step S 106 . Alternatively, if the last region has been considered (“yes” in Step S 118 ), variables Page1Bytes, Page2Bytes, Page3Bytes, and Page4Bytes are stored in portion  84  of the STIMMAP table  82 , and the routine is concluded. 
   In reference to the area conversion routine illustrated in  FIG. 15 , a decision is initially made at Step S 124  whether the originating call to the subroutine came from Step S 110  or Step S 116 , or more particularly, whether the subject region derives from the anterior stimulation image or the posterior stimulation image. If “anterior,” the conversion table of  FIG. 12  is referenced (Step S 126 ), and alternatively, the conversion table of  FIG. 13  is referenced (Step S 128 ). 
   In Step S 130 , after correlating the Area_Number variable and the values of Column 1 of the proper conversion table, values are extracted for the “Screen Display Page,” “Left Side Column,” “Left Bit Mask,” “Right Side Column,” and “Right Bit Mask.” From the “Screen Display Page” value extracted in Step S 130 , the Page_Byte_List variable is equated to one of the Page1Bytes, Page2Bytes, Page3Bytes, and Page4Bytes variables in Step S 132 . In Step S 134 , the current byte value is extracted from the page defined by the Page_Byte_List variable. In this instance, the “Left Side Column” value is used as an index into the Page_Byte_List page. Step S 136  effects a logical “ORing” of the extracted current byte value (from Step S 134 ) and the “Left Bit Mask” value (from Step S 130 ). The output of Step S 136  is returned as the subject byte value to the Page_Byte_List page (Step S 138 ). 
   In Step S 140 , the current byte value is extracted from the page defined by the Page_Byte_List variable using the “Right Side Column” value as an index into the Page_Byte_List page. Step S 142  effects a logical “ORing” of the extracted current byte value (from Step S 140 ) and the “Right Bit Mask” value (from Step S 130 ). The output of Step S 142  is returned as the subject byte value to the Page 13  Byte_List page (Step S 144 ). The routine returns following these conversion steps. 
   Consistent with the description of the algorithm of  FIG. 15  and the illustration of  FIG. 10 , it should be noted that the regional segmentation of both the anterior image and the posterior image is designed to produce regionally-compatible images. Specifically, the anterior image and the posterior image should maintain the same number of regions, and the regions should be consistently arranged so that like-numbered (i.e., like-identified) regions will effectively merge upon the symmetrical overlay of the anterior and posterior images. 
   For at least this example, the composite bodily image displayable on the display  50  is provided with a number of regions numerically consistent with one of either the anterior or the posterior stimulation images from the computer  128 . It is contemplated, however, that this will not always be achievable, wherein the composite bodily image for the transmitter  102  will be required to display an abridged version of the image data of the stimulation images. To this end, the algorithm of  FIG. 15  would further be required to assess each region, and a number of adjacent region(s) (the number of adjacent regions being dependent upon the available resolution of the composite bodily graphic), for purposes of combining the graphical data of such regions for display in display  50 . 
   While the above algorithm describes a graphical conversion process that occurs at the time of data storage, it should be appreciated that the timing for such conversion is not critical. Rather, the graphical conversion could instead occur at the time of downloading the stimulation settings and the program controls from the computer  128  to the transmitter  102 . 
   Of further note, much of information conveyed here regarding the conversion algorithm is a function of the very specific display  50  chosen for the described embodiment. Consequently, it should be noted that substantive information within the conversion tables ( FIGS. 12 and 13 ), described means for addressing the display  50  (e.g., 1 byte instructions, coordinate addressing based on columns and pages, etc.), and the like serve only as one exemplary form of the present invention. The use of other displays could alter these particular aspects of the above disclosure; however, any such substitution would not be outside the scope of the disclosed invention. 
   Therapy Definition 
   Upon completing the definition and testing of various stimulation parameters, all of the recorded stimulation settings are displayed in, and are available for selection through, Region  216  of the screen shot of  FIG. 9B . Program, or therapy, creation is achieved by the following steps: 
   Step A: A program is selected from Region  226 . Each program can be named using an alphanumeric designation (e.g., “sleeping,” “sitting,” “standing,” etc.). Depending on the system, such alphanumeric designation may or may not be transferred to the transmitter  102 . If transferred, such designation could be displayed in display  50 . As but one example, such designation could be displayed in at least the program selection mode ( FIGS. 7A–7D ) to better assist a user in appreciating the intended purpose of each program in the event such purpose cannot be gleaned from the displayed composite graphic. As an alternative to displaying the designation, the transmitter  102  could store the designation in memory for later transfer to a newly connected computer  128  to provide additional information to a reviewing physician. 
   Step B: With a program selected, a number of stimulation settings can then be selected from Region  216 . As stated above, for a most preferred embodiment, no more than eight stimulation settings can be attributed to any one program. 
   Step C: With the desired stimulation setting(s) selected, the “Add Stim Set(s) to Prog.” screen button (Region  218 ) is actuated. Upon actuation, the software effects the following actions: (i) corresponding stimulation setting(s) is/are added to the selected program; (ii) entries corresponding to the transferred stimulation settings are created in the STIMSET table  76 , and links are established between such entries and the PROGRAMS table  74 ; and (iii) TESTRES and STIMMAP references are added to the new STIMSET records. 
   Step D: Upon completing the therapy definition, the “download programs” screen button (Region  222 ) can be actuated, and if so, the indicated programs, with related stimulation settings, are transferred to the connected transmitter  102 . 
   During the download process, it is preferred that a status screen ( FIG. 9C ) be provided to inform the user as to the progress of the download. At least in the illustrated embodiment, at Region  224 , stimulation graphics corresponding to at least the individual stimulation settings are shown as they are downloaded. Although the creation of a program&#39;s composite graphic ( FIG. 5 ) can occur at any time after definition of the program, it is preferred that during the downloading process, the individual graphic regions of each stimulation settings are subject to a logical “ORing”, and the result of such process is stored in the COMPOSITE GRAPHIC field of a program data file ( FIG. 4 ). 
   GENERAL 
   While the above description focuses on the use of a general purpose computer (e.g., laptop or desktop systems), using conductive or alternative connection methods (e.g., infrared transmission, radio-frequency transmission, ultrasonic transmission, etc.), it should be appreciated that the “computer” of the present invention could equally be represented by a dedicated hand-held programmer or portable computing devices, e.g., Palm®-type devices, Windows™ CE-based devices, and the like. 
   Although this disclosure has concentrated its examples on RF stimulation systems, there is no limitation that would prevent this invention from being applied to implanted pulse generator (IPG) systems that offer multiple stimulation settings or therapy programs. 
   While the above description further focuses on the present invention being used in the context of spinal cord stimulation systems, it should be noted that the present invention is equally applicable to any application that experiences the frustrations identified above for systems that store multiple applications without sufficient means to readily identify such applications. As but a few examples where the present invention might obviously benefit the current state of the art, deep brain stimulation (DBS), transcutaneous electrical nerve stimulation (TENS), pulsed electromagnetic stimulation (PEMS), biofeedback applications, and programmable drug delivery systems. 
   Although visual imagery is believed to impart the greatest understanding to a user in a limited-sized display, it is not beyond the scope of this invention that the displayed stimulation “graphic” consist of or include a textual description of the specific stimulation setting and/or program. Such textual description could be fully descriptive (e.g., “upper torso”) or simply use abbreviations (e.g., “UT”). Moreover, the textual descriptions could be provided by the user at the. time of defining and testing the stimulation parameters or at the time of assembling the various programs, or the computer could formulate such textual descriptions, from a listing of prescribed options, based on the data used to otherwise generate the transmitter-based graphics. 
   While the invention has been described herein relative to a number of particularized embodiments, it is understood that modifications of, and alternatives to, these embodiments, such modifications and alternatives realizing the advantages and benefits of this invention, will be apparent to those of ordinary skill in the art having reference to this specification and its drawings. It is contemplated that such modifications and alternatives are within the scope of this invention as subsequently claimed herein, and it is intended that the scope of this invention claimed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.
A neuromodulation therapy system includes a programmer and a stimulation system. The stimulation system is capable of storing multiple data sets, each data set effecting an independent therapy. The stimulation system includes a display mechanism that can display certain imagery to distinguish visually one therapy from another therapy.