Abstract:
A suture bar for securing an implantable medical device into a body. The suture bar including a body member having a length disposed between a first and a second end, the body member being formed of a generally elongate tube that is piercable by a suture needle. The suture bar also including a first and second connector fixedly attached on the first and second end of the body member, the first and second connector operable to connect the implantable medical device to a pocket in a body.

Description:
TECHNICAL FIELD 
       [0001]    This disclosure relates to structures for securing an implantable device into an implant pocket. More specifically, the disclosure relates to a suture ring for securing an implantable device into a body. 
       BACKGROUND 
       [0002]    A variety of medical devices are used for chronic, i.e., long-term, delivery of therapy to patients suffering from a variety of conditions, such as chronic pain, tremor, Parkinson&#39;s disease, epilepsy, urinary or fecal incontinence, sexual dysfunction, obesity, spasticity, or gastroparesis. As examples, electrical stimulation generators are used for chronic delivery of electrical stimulation therapies such as cardiac pacing, neurostimulation, muscle stimulation, or the like. Pumps or other fluid delivery devices may be used for chronic delivery of therapeutic agents, such as drugs. Typically, such devices provide therapy continuously or periodically according to parameters contained within a program. A program may comprise respective values for each of a plurality of parameters, specified by a clinician. The devices may be implantable medical devices that receive the program from a programmer controlled by the clinician. 
         [0003]    Examples of such implantable medical devices include implantable fluid delivery devices, implantable neurostimulators, implantable cardioverters, implantable cardiac pacemakers, implantable defibrillators, cochlear implants, and others that now exist or may exist in the future. These devices are intended to provide a patient with a therapeutic output to alleviate or assist with a variety of conditions. Typically, such devices are implanted in a patient and provide a therapeutic output under specified conditions on a recurring basis. 
         [0004]    One type of implantable medical device (IMD) is an implantable fluid delivery device that delivers a drug, medication or other substance, typically in fluid form, to a patient at a selected therapy site. An implantable fluid delivery device may be implanted at a location in the body of a patient and deliver a fluid through a catheter to a selected delivery site in the body. Drug IMDs, such as implantable fluid delivery pumps, typically include fluid reservoirs that may be self-sealing and may be percutaneously accessible through ports. A fluid delivery device may be configured to deliver a therapeutic agent, such as a drug, from the fluid reservoir to a patient according to a therapy program. The therapy program may specify, for example, the amount of the therapeutic agent delivered to the patient, the concentration of the therapeutic agent, and/or the delivery rate of the therapeutic agent. 
         [0005]    IMDs are normally sutured into the body of the patient using sutures placed through suture loops located on the outside of the housing of the medical device. Typically, four suture loops may be positioned on the housing to secure the IMD. However, depending on how the IMD is positioned in the implant pocket, the surgeon implanting the device may not be able to utilize all of the suture loops to secure the IMD. Improvements in structures and methods for securing IMDs are therefore useful. 
       SUMMARY 
       [0006]    The present description includes a suture ring that can be secured into a pocket of a patient and thereafter secured so as to provide a place onto which to snap an implantable medical device. 
         [0007]    The suture ring provides improved ease of implantation for the IMD. The suture ring provides a more robust selection of suture sites for the clinician (surgeon) to attach the IMD to the implant pocket. The suture ring may free the clinician from only having four distinct points in which to place sutures to secure the IMD 
         [0008]    The present invention includes a device for facilitating the attachment of an implantable medical device in a body, comprising a suture ring, suture retention means located on the suture ring for securing the suture ring into a desired position, and an attachment means located on the suture ring for engaging corresponding attachment points on the implantable medical device, the attachment means removably securing the implantable medical device to the suture ring. 
         [0009]    Also included herein is a method of securing an implantable medical device into a body comprising providing an implantable medical device and a suture ring, the implantable medical device including a plurality of attachment points that corresponding to and will matingly engage to connectors on the suture ring, creating a pocket in a body, securing the suture ring into the pocket by suturing it into a desired position, and securing the implantable medical device into the pocket in a desired position by attaching the medical device to the suture ring through engagement of the corresponding attachment points and connectors. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0010]      FIG. 1  is a conceptual diagram illustrating an example of a fluid delivery system, which includes an implantable medical device that is configured to deliver a therapeutic agent to a patient via a catheter. 
           [0011]      FIG. 2  is a conceptual diagram illustrating the placement of an implantable medical device of the present invention. 
           [0012]      FIG. 3  is functional block diagram illustrating an example of an implantable fluid delivery device. 
           [0013]      FIG. 4  is a functional block diagram illustrating example components of an external programmer for an implantable medical device. 
           [0014]      FIG. 5A  is a diagram illustrating an implantable medical device with an example suture ring of the present invention. 
           [0015]      FIG. 5B  is a perspective view of the implantable medical device and suture ring of  FIG. 5A  with the implantable medical device attached to the suture ring. 
           [0016]      FIG. 5C  is a plan view of the implantable medical device and suture ring of  FIG. 5B . 
           [0017]      FIG. 6A  is diagram illustrating an implantable medical device with an alternative embodiment suture ring. 
           [0018]      FIG. 6B  is a perspective view of the implantable medical device and suture ring of  FIG. 6A  with the implantable medical device attached to the suture ring. 
           [0019]      FIG. 6C  is a plan view of the implantable medical device and suture ring of  FIG. 6B . 
           [0020]      FIG. 7A  is a diagram illustrating an implantable medical device with another alternative embodiment suture ring. 
           [0021]      FIG. 7B  is a perspective view of the implantable medical device and suture ring of  FIG. 7A  with the implantable medical device attached to the suture ring. 
           [0022]      FIG. 8A  is a diagram illustrating an implantable medical device with another alternative embodiment suture ring. 
           [0023]      FIG. 8B  is a perspective view of the implantable medical device and suture ring of  FIG. 8A  with the implantable medical device attached to the suture ring. 
           [0024]      FIG. 9A  is a diagram illustrating an implantable medical device with another alternative embodiment suture ring. 
           [0025]      FIG. 9B  is a perspective view of the implantable medical device and suture ring of  FIG. 9A  with the implantable medical device attached to the suture ring. 
           [0026]      FIG. 10A  is a diagram illustrating an implantable medical device with another alternative embodiment suture ring. 
           [0027]      FIG. 10B  is a perspective view of the implantable medical device and suture ring of  FIG. 10A  with the implantable medical device attached to the suture ring. 
           [0028]      FIG. 11A  is a diagram illustrating an implantable medical device with another alternative embodiment suture ring. 
           [0029]      FIG. 11B  is a perspective view of the implantable medical device and suture ring of  FIG. 11A  with the implantable medical device attached to the suture ring. 
           [0030]      FIG. 11C  is a perspective view of the pin illustrated in  FIG. 11A . 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    Medical devices are useful for treating, managing or otherwise controlling various patient conditions or disorders, such as, but not limited to, pain (e.g., chronic pain, post-operative pain or peripheral and localized pain), tremor, movement disorders (e.g., Parkinson&#39;s disease), diabetes, epilepsy, neuralgia, chronic migraines, urinary or fecal incontinence, sexual dysfunction, obesity, gastroparesis, mood disorders, or other disorders. Some medical devices may be configured to deliver one or more therapeutic agents, alone or in combination with other therapies, such as electrical stimulation, to one or more target sites within a patient. For example, in some cases, a medical device may deliver one or more pain-relieving drugs to patients with chronic pain, insulin to a patient with diabetes, or other fluids to patients with different disorders. The medical device may be implanted in the patient for chronic therapy delivery (e.g., longer than a temporary, trial basis) or temporary delivery. 
         [0032]    The following detailed description is of the presently contemplated mode of implementing the invention. The embodiment herein is described in terms of an implantable medical device (IMD) that could be any type of device implanted into a body, including, for example, a drug pump, a stimulator, a monitor, a catheter, etc. This description is not to be taken in a limiting sense, but is merely for the purpose of illustrating the general principles of embodiments of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description of the invention. The scope of the invention is defined by the appended claims. 
         [0033]      FIG. 1  shows an IMD  10 . The illustrated IMD  10  is configured to be surgically implanted into a patient, for example, in the abdominal region, between the skin and the abdominal wall, and is part of a therapy system that may include a catheter connected to the IMD  10 . The catheter may deliver infusion medium to the patient, for example, but not limited to, by feeding infusion medium to a particular location in the venous system, within the spinal column, or in the peritoneal cavity of the patient. The therapy system may also include a programmer or other device for controlling the functions of the IMD. For purposes of simplifying the present disclosure, the term “patient” is used herein to refer to any environment in which an implantable device is implanted, whether or not the implant or connection is carried out for medical purposes. The patient may also be referred to by the term “body” to refer to the patient&#39;s body. Also, the term “infusion medium” is used herein to refer to any suitable medium delivered by the IMD  10 . 
         [0034]    The IMD  10  may include a generally disc-shaped housing  14 . While a generally circular disc-shaped embodiment is illustrated in  FIG. 1 , it will be understood that further embodiments of the IMD  10  may employ housing of other shapes, including, but not limited to, oval, oblong, rectangular, or other curved or polygonal shapes. Generally, the housing  14  is made of a biocompatible material and most often has a relatively small diameter and thickness to reduce patient trauma during implant surgery and after implantation. Generally, IMD  10  has an outer housing that is constructed of a biocompatible material that resists corrosion and degradation from bodily fluids, such as titanium or biologically inert polymers. 
         [0035]    The housing  14  includes a reservoir  16  for holding a volume of infusion medium, such as, but not limited to, a liquid medication to be administered to the patient. Housing  14  may also contain a drive mechanism  18  (e.g. a pump), a power source  13 , and control electronics  20 . Pump  18  may be configured to receive infusion media from reservoir  16  via a pump inlet  22 . Inlet structure  22  may provide a closeable and sealable fluid flow path to the reservoir in the reservoir portion of the housing. The inlet structure may include a port for receiving a needle through which fluid may be transferred to the IMD, for example, to fill or re-fill the reservoir of the device with the infusion media or a rinsing fluid as will be more fully discussed below. In particular embodiments, the inlet structure may be configured to re-seal after a fill or re-fill operation, and to allow multiple re-fill and re-seal operations. One example of an inlet structure is described in U.S. Pat. No. 6,652,510, titled “Implantable Medical Device and Reservoir for Same,” which is incorporated by reference herein in its entirety and for everything it teaches and discloses. However, further embodiments may employ other suitable inlet structures, including, but not limited to, those described in U.S. Pat. Nos. 5,514,103 and 5,176,644, each to Srisathapat et al.; U.S. Pat. No. 5,167,633 to Mann et al.; U.S. Pat. No. 4,697,622 to Swift; and U.S. Pat. No. 4,573,994 to Fischell et al., also incorporated by reference. Representative examples of reservoir housing portions and reservoirs which may be employed in embodiments of the invention are described in the above referred to U.S. Pat. No. 6,652,510, and further embodiments may employ other suitable reservoir configurations, including, but not limited to, those described in the above referred to U.S. Pat. Nos. 5,514,103; 5,176,644; 5,167,633; 4,697,622; and 4,573,994. The IMD  10  may further include an outlet  12 . The outlet  12  illustrated is sized and shaped to connect to a catheter  22  (see below) and to operably attach the catheter  22  to the IMD  10  to receive the therapeutic agent as further discussed below. 
         [0036]      FIG. 2  is a conceptual diagram illustrating an example of a therapy system, which includes IMD  10  configured to deliver at least one therapeutic agent, such as a pharmaceutical agent, insulin, pain relieving agent, anti-inflammatory agent, gene therapy agent, or the like, to a target site within patient  23  via catheter  22 , which is coupled to IMD  10 . In one example, catheter  22  may comprise a plurality of catheter segments. In the example of  FIG. 2 , the therapeutic agent is a therapeutic fluid. IMD  10  may be, for example, an implantable fluid delivery device that delivers therapeutic agents in fluid form to patient  23 . In the example shown in  FIG. 1 , the target site is proximate to spinal cord  19  of patient  23 . A proximal end of catheter  22  is coupled to IMD  10 , while a distal end of catheter  22  is located proximate to the target site. In the present embodiment, therapy system  10  may also include an external programmer  80 , which wirelessly communicates with IMD  10  as needed, such as to provide or retrieve therapy information or control aspects of therapy delivery (e.g., modify the therapy parameters, turn IMD  10  on or off, and so forth). Programmer  80  may include a user interface that may display a representation of a portion of an implantable fluid delivery device and simultaneously display an indication of a location of fluid within the implantable fluid delivery device during a delivery phase, as discussed in greater detail below. While patient  23  is generally referred to as a human patient, other mammalian or non-mammalian patients are also contemplated. In other examples, IMD  10  may be implanted within other suitable sites within patient  23 , which may depend, for example, on the target site within patient  23  for the delivery of the therapeutic agent. 
         [0037]    The IMD  10  and catheter  22  are typically implanted by a clinician (e.g., surgeon) within the body  23  during a surgical procedure. A proximal end of the catheter  22  may be tunneled through the tissue to the IMD  10  location and coupled to a catheter port of the IMD  10 . If implanted, the medical device  10  is typically positioned subcutaneously, e.g., from 1 centimeter (0.4 inches) to 2.5 centimeters (1 inch) beneath the skin, where there is sufficient tissue for supporting the IMD  10 , e.g., with sutures or the like. 
         [0038]    Therapy system may be used, for example, to reduce pain experienced by patient  23 . IMD  10  may deliver one or more therapeutic agents to patient  23  according to one or more therapy programs that set forth different therapy parameters, such as bolus size, frequency of bolus delivery, time during which a bolus is to be delivered, and so forth. In some examples, the therapeutic agent may be a liquid. The therapy programs may be may be a part of a program group for therapy, where the group includes a plurality of therapy programs. In some examples, IMD  10  may be configured to deliver a therapeutic agent to patient  23  according to different therapy programs on a selective basis. IMD  10  may include a memory to store one or more therapy programs, instructions defining the extent to which patient  23  may adjust therapy parameters, switch between programs, or undertake other therapy adjustments. Patient  23  may select and/or generate additional therapy programs for use by IMD  10  via external programmer  80  at any time during therapy or as designated by the clinician. 
         [0039]    In some examples, multiple catheters  18  may be coupled to IMD  10  to target the same or different tissue or nerve sites within patient  23 . Thus, although a single catheter  22  is shown in  FIG. 1 , in other examples, system  12  may include multiple catheters or catheter  22  may define multiple lumens for delivering different therapeutic agents to patient  23  or for delivering a therapeutic agent to different tissue sites within patient  23 . Accordingly, in some examples, IMD  10  may include a plurality of reservoirs for storing more than one type of therapeutic agent. In some examples, IMD  10  may include a single long tube that contains the therapeutic agent in place of a reservoir. However, for ease of description, an IMD  10  including a single reservoir is primarily discussed herein with reference to the example of  FIG. 1 . 
         [0040]      FIG. 3  is a functional block diagram illustrating components of an example of IMD  10 , which includes refill port  22 , reservoir  16 , processor  20 , memory  40 , telemetry module  42 , power source  13 , fluid delivery pump  18 , internal tubing  32 , and catheter access port  36 . Fluid delivery pump  18  may be a mechanism that delivers a therapeutic agent in a metered or desired flow rate to the therapy site within patient  23  from reservoir  16  via the catheter  22 . Refill port  21  may comprise a self-sealing membrane to prevent loss of therapeutic agent delivered to reservoir  16  via refill port  21 . After a delivery system, e.g., a hypodermic needle, penetrates the membrane of refill port  21 , the membrane may seal shut when the needle is removed from refill port  21 . 
         [0041]    Internal tubing  32  is a segment of tubing that runs from reservoir  16 , around or through fluid delivery pump  18 , to catheter access port  36 . In one example, fluid delivery pump  18  may be a squeeze pump that squeezes internal tubing  32  in a controlled manner, e.g., such as a peristaltic pump, to progressively move fluid from reservoir  16  to the distal end of catheter  22  and then into the patient  23  according to parameters specified by a set of program information. Fluid delivery pump  18  may, in other examples, comprise an axial pump, a centrifugal pump, a pusher plate, a piston-driven pump, or other means for moving fluid through internal tubing  32  and catheter  22 . 
         [0042]    Processor  20  controls the operation of fluid delivery pump  18  with the aid of program information stored in memory  40 . For example, the program information may include instructions that define therapy programs to specify the amount of a therapeutic agent that is delivered to a target tissue site within patient  23  from reservoir  16  via catheter  22 . The instructions may further specify the time at which a bolus will be delivered and the time interval over which the bolus will be delivered, e.g., as defined by a start and an end time. The therapy programs may also include other therapy parameters, such as the frequency of bolus delivery, the type of therapeutic agent delivered (if IMD  10  is configured to deliver more than one type of therapeutic agent), and so forth. Components described as processors within IMD  10 , external programmer  80 , or any other device described in this disclosure may each comprise one or more processors, such as one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), programmable logic circuitry, or the like, either alone or in any suitable combination. 
         [0043]    Memory  40  may include any volatile or non-volatile media, such as a random access memory (RAM), read only memory (ROM), non-volatile RAM (NVRAM), electrically erasable programmable ROM (EEPROM), flash memory, and the like. As mentioned above, memory  40  may store program information including instructions for execution by processor  20 , such as, but not limited to, therapy programs, historical therapy programs, timing programs for delivery of fluid from reservoir  16  to catheter  22 , and any other information regarding therapy of patient  23 . A program may indicate the bolus size or flow rate of the drug, and processor  20  may accordingly deliver therapy. Memory  40  may include separate memories for storing instructions, patient information, therapy parameters (e.g., grouped into sets referred to as “therapy programs”), therapy adjustment information, program histories, and other categories of information such as any other data that may benefit from separate physical memory modules. Therapy adjustment information may include information relating to timing, frequency, rates and amounts of patient boluses or other permitted patient modifications to therapy. In some examples, memory  40  stores program instructions that, when executed by processor  20 , cause IMD  10  and processor  20  to perform the functions attributed to them in this disclosure. 
         [0044]    Telemetry module  42  in IMD  10 , as well as telemetry modules in other devices described herein, such as programmer  80 , may accomplish communication by RF communication techniques. In other embodiments, telemetry module  42  may communicate with the programmer  80  in other methods, such as, for instance, telemetry module  42  may communicate with programmer  80  via proximal inductive interaction. Accordingly, telemetry module  42  may send information to external programmer  80  on a continuous basis, at periodic intervals, or upon request from the programmer. Processor  20  controls telemetry module  42  to send and receive information. 
         [0045]    Power source  13  delivers operating power to various components of IMD  10  (connection lines not shown). Power source  13  may include a small rechargeable or non-rechargeable battery and a power generation circuit to produce the operating power. In the case of a rechargeable battery, recharging may be accomplished through proximal inductive interaction between an external charger and an inductive charging coil within IMD  10 . In other embodiments, power requirements may be small enough to allow IMD  10  to utilize patient motion and implement a kinetic energy-scavenging device to trickle charge a rechargeable battery. In other examples, traditional batteries may be used for a limited period of time. As a further alternative, an external inductive power supply could transcutaneously power IMD  10  whenever measurements are needed or desired. 
         [0046]    Programmer  80 , as further discussed and detailed herein, may be an external computing device that is configured to wirelessly communicate with IMD  10 . For example, programmer  80  may be a clinician programmer that the clinician uses to communicate with IMD  10 . Alternatively, programmer  80  may be a patient programmer that allows patient  23  to view and modify therapy parameters. The clinician programmer may include additional or alternative programming features than the patient programmer. For example, more complex or sensitive tasks may only be allowed by the clinician programmer to prevent patient  23  from making undesired changes to the operation of IMD  10 . 
         [0047]    Programmer  80  may be a hand-held computing device that includes a display viewable by the user and a user input mechanism that can be used to provide input to programmer  80 . For example, programmer  80  may include a small display screen (e.g., a liquid crystal display or a light emitting diode display) that presents information to the user. In addition, programmer  80  may include a keypad, buttons, a peripheral pointing device, touch screen or another input mechanism that allows the user to navigate though the user interface of programmer  80  and provide input. 
         [0048]    If programmer  80  includes buttons and a keypad, the buttons may be dedicated to performing a certain function, i.e., a power button, or the buttons and the keypad may be soft keys that change in function depending upon the section of the user interface currently viewed by the user. Alternatively, the screen (not shown) of programmer  80  may be a touch screen that allows the user to provide input directly to the user interface shown on the display. The user may use a stylus or their finger to provide input to the display. 
         [0049]    In other examples, rather than being a handheld computing device or a dedicated computing device, programmer  80  may be a larger workstation or a separate application within another multi-function device. For example, the multi-function device may be a cellular phone, personal computer, laptop, workstation computer, or personal digital assistant that can be configured to an application to simulate programmer  80 . Alternatively, a notebook computer, tablet computer, or other personal computer may enter an application to become programmer  80  with a wireless adapter connected to the personal computer for communicating with IMD  10 . 
         [0050]    When programmer  80  is configured for use by the clinician, programmer  80  may be used to transmit initial programming information to IMD  10 . This initial information may include hardware information for system  10  such as the type of catheter  22 , the position of catheter  22  within patient  23 , the type of therapeutic agent(s) delivered by IMD  10 , a baseline orientation of at least a portion of IMD  10  relative to a reference point, therapy parameters of therapy programs stored within IMD  10  or within programmer  80 , and any other information the clinician desires to program into IMD  10 . 
         [0051]    Whether programmer  80  is configured for clinician or patient use, programmer  80  may communicate to IMD  10  or any other computing device via wireless communication. Programmer  80 , for example, may communicate via wireless communication with IMD  10  using radio frequency (RF) telemetry techniques known in the art. Programmer  80  may also communicate with another programmer or computing device via a wired or wireless connection using any of a variety of local wireless communication techniques, such as RF communication according to the 802.11 or Bluetooth specification sets, infrared (IR) communication according to the IRDA specification set, or other standard or proprietary telemetry protocols. Programmer  80  may also communicate with another programming or computing device via exchange of removable media, such as magnetic or optical disks, or memory cards or sticks. Further, programmer  80  may communicate with IMD  10  and another programmer via remote telemetry techniques known in the art, communicating via a local area network (LAN), wide area network (WAN), public switched telephone network (PSTN), or cellular telephone network, for example. 
         [0052]    In other applications of therapy system  10 , the target therapy delivery site within patient  23  may be a location proximate to sacral nerves (e.g., the S 2 , S 3 , or S 4  sacral nerves) in patient  23  or any other suitable nerve, organ, muscle or muscle group in patient  23 , which may be selected based on, for example, a patient condition. For example, therapy system  10  may be used to deliver a therapeutic agent to tissue proximate to a pudendal nerve, a perineal nerve or other areas of the nervous system. In some instances catheter  22  may be implanted and substantially fixed proximate to the respective nerve. As further examples, catheter  22  may be positioned to deliver a therapeutic agent to help manage peripheral neuropathy or post-operative pain mitigation, ilioinguinal nerve therapy, intercostal nerve therapy, gastric stimulation for the treatment of gastric motility disorders and/or obesity, muscle stimulation, for mitigation of other peripheral and localized pain (e.g., leg pain or back pain). As another example, catheter  22  may be positioned to deliver a therapeutic agent to a deep brain site or within the heart (e.g., intraventricular delivery of the agent). Delivery of a therapeutic agent within the brain may help manage any number of disorders or diseases. Example disorders may include depression or other mood disorders, dementia, obsessive-compulsive disorder, migraines, obesity, and movement disorders, such as Parkinson&#39;s disease, spasticity, and epilepsy. Catheter  22  may also be positioned to deliver insulin to a patient with diabetes. 
         [0053]    Examples of therapeutic agents that IMD  10  may be configured to deliver include, but are not limited to, insulin, morphine, hydromorphone, bupivacaine, clonidine, other analgesics, genetic agents, antibiotics, nutritional fluids, analgesics, hormones or hormonal drugs, gene therapy drugs, anticoagulants, cardiovascular medications or chemotherapeutics. Various embodiments of the present invention may be utilized with any type of medical device that is to be implanted into the body to aid in securing the medical device into the desired position. 
         [0054]      FIG. 4  is a functional block diagram illustrating various components of one example external programmer  80  for IMD  10 . As shown in  FIG. 4 , external programmer  80  includes processor  84 , memory  86 , telemetry module  88 , user interface  82 , and power source  90 . A clinician or patient  23  interacts with user interface  82  in order to manually change the parameters of a program, change programs within a group of programs, view therapy information, view historical therapy regimens, establish new therapy regimens, or otherwise communicate with IMD  10  or view programming information. 
         [0055]    User interface  82  may include a screen and one or more input buttons, as discussed in greater detail below, that allow external programmer  80  to receive input from a user. Alternatively, user interface  82  may additionally or only utilize a touch screen display, as in the example of clinician programmer  60 . The screen may be a liquid crystal display (LCD), dot matrix display, organic light-emitting diode (OLED) display, touch screen, or any other device capable of delivering and/or accepting information. For visible indications of therapy program parameters or operational status, a display screen may suffice. For audible and/or tactile indications of therapy program parameters or operational status, programmer  80  may further include one or more audio speakers, voice synthesizer chips, piezoelectric buzzers, or the like. 
         [0056]    Input buttons for user interface  82  may include a touch pad, increase and decrease buttons, emergency shut off button, and other buttons needed to control the therapy, as described above with regard to patient programmer  80 . Processor  84  controls user interface  82 , retrieves data from memory  86  and stores data within memory  86 . Processor  84  also controls the transmission of data through telemetry module  88  to IMD  10 . The transmitted data may include therapy program information specifying various drug delivery program parameters. Memory  86  may include operational instructions for processor  84  and data related to therapy for patient  23 . User interface  82  may be configured to present therapy program information to the user. User interface  82  enables a user to program IMD  10  in accordance with one or more therapy delivery programs, schedules, or the like. The therapy program information may also be stored within memory  86  periodically during therapy, whenever external programmer  80  communicates within IMD  10 , or only when the user desires to use or update the therapy program information. 
         [0057]    Telemetry module  88  allows the transfer of data to and from IMD  10 . Telemetry module  88  may communicate automatically with IMD  10  at a scheduled time or when the telemetry module detects the proximity of IMD  10 . Alternatively, telemetry module  88  may communicate with IMD  10  when signaled by a user through user interface  82 . To support RF communication, telemetry module  88  may include appropriate electronic components, such as amplifiers, filters, mixers, encoders, decoders, and the like. Power source  90  may be a rechargeable battery, such as a lithium ion or nickel metal hydride battery. Other rechargeable or conventional batteries may also be used. In some cases, external programmer  80  may be used when coupled to an alternating current (AC) outlet, i.e., AC line power, either directly or via an AC/DC adapter. 
         [0058]    In some examples, external programmer  80  may be configured to recharge IMD  10  in addition to programming IMD  10 . Alternatively, a recharging device may be capable of communication with IMD  10 . Then, the recharging device may be able to transfer programming information, data, or any other information described herein to IMD  10 . In this manner, the recharging device may be able to act as an intermediary communication device between external programmer  80  and IMD  10 . The techniques described in this disclosure may be communicated between IMD  10  via any type of external device capable of communication with IMD  10 . 
         [0059]      FIGS. 5A-C  illustrates an IMD  10  with a suture ring  100  of the present invention. The suture ring  100  includes a body member  102  in the shape of a generally circular ring or hoop. The body member  102  is the main structural element of the suture ring  100  and includes a number of suture holes  104  and prongs  106 . The suture holes  104  are bores or openings through the body member  102  and may be placed at any desired pattern or spacing around the circumference of the body member  102 . The suture ring  100  may be secured into the pocket of the patient by suturing suture ring  100  to the patient through the suture holes  104 . The suture ring  100  provides a platform for anchoring the IMD  10  into the desired position. 
         [0060]    The prongs  106  are placed at positions around the body member  102  to correspond to complementary attachment points  108  on the IMD  10 . As further described below, the prongs  106  are sized and shaped to couple or detachably connect to the attachment points  108  on the IMD  10  so that the IMD  10  can be locked or secured to the suture ring  100 . In various embodiments the prongs  106  may be replaced by any type of attachment member known to those of skill in the art, some embodiments of which are further discussed below. 
         [0061]    The suture ring  100  may include one or more guides  109 . The guides  109  may be of a size and shape to engage the outer bottom surface of the IMD  10  to guide IMD  10  into the desired alignment with suture ring  100 . The guides  109  may improve the mating of the prongs  106  to the attachment points  108  of the suture ring  100  by insuring proper alignment. In addition, the guides  109  and the guide receptors may help to guard against movement of the IMD  10  relative to the suture ring  100 . In further embodiments, guides  109  may be received into the housing  14  of the IMD  10  in guide receptors (not shown) that further help to align and lock the IMD  10  to the suture ring  100 . 
         [0062]    An inner diameter of the body member  102  may have a shape and size that matches or closely conforms to an outer bottom edge  110  of the IMD  10 . The body member  102  may also have a width W. The width W should be large enough for placement of the suture holes  104  and the prongs  106  and for the desired structural integrity of the suture ring. As may be appreciated, the width W may vary depending on the material selected to manufacture suture ring  100 . 
         [0063]    The sutures placed through the suture holes  104  of the suture ring  100  allow for the IMD  10  to be secured into the desired location with more selectivity as to the suturing site, depending on the number of suture holes  104  provided in the body member  102 . In further embodiments, the suture holes  104  may be of any shape or size, such as ovals or long cutouts. Such embodiments may provide the implanter with a greater choice in the number of sutures and the placement of the sutures in the pocket. The number of suture holes  104  and the size thereof may be in part dictated by the type of material used to make the suture body  102  such that the desired structural stiffness is maintained. As may be appreciated, the suture holes  104  may be any type of structure to which a suture may be attached. Some embodiments of different structures are discussed below. 
         [0064]    In other embodiments the cross section of the body member  102  may be circular or oval so as to reduce any sharp edges and provide less irritability to the tissue of the patient. In still further embodiments, the suture bar  100  may be made of a hollow tubular structure that is of sufficient stiffness to retain the IMD  10 . In still further embodiments, the body member  102  my have a variety of cross section shapes and widths at different points to enhance the structural integrity or to reduce the overall volume of the space occupied. 
         [0065]    The suture ring  100  may be made of any biocompatible material that is known to those of skill in the art that provides sufficient strength to retain the IMD  10  in the desired position after being sutured into the pocket of the patient. For example, the body member  102  may be made of a biocompatible metal such as titanium. In further embodiments the body member  102  may be made of a polymer, such as, for example, polyethylene terephthalate (PET). Other suitable materials may be material that is used in making suture materials, such as polypropylene, polyester, or nylon. Other materials may have various properties as desired, such as being elastic. Elastic materials may include copolymers of styrene-butadiene, polybutadiene, polymers formed from ethylene-propylene diene monomers, polychloroprene, polyisoprene, copolymers of acrylonitrile and butadiene, copolymers of isobutyldiene and isoprene, polyurethanes and the like. In still further embodiments, the suture ring  100  may be made of a combination of materials that exhibit different properties. The prongs  106  may be made of a stiffer material such as a metal or hard polymer to effectuate attachment to the attachment points  108  while the body member  102  may be made of a relatively more flexible material, but one that still provides sufficient strength to secure the IMD  10  into the desired position. 
         [0066]    As illustrated, the attachment points  108  may be placed on a side of the housing  14  of IMD  10 . In further embodiments, the attachment points  108  may be placed at any point on the housing  14 , such as on the bottom surface of the housing  14 , whereby the attachment points  108  do not increase the overall diameter of the IMD  10 . In such an embodiment the corresponding prongs  106  and attachment points may be a male and female snap, claps, or other connection means. In still further embodiments, the attachment points  108  may be arranged as a recess into the IMD  10  housing  14  itself, such that the prongs  106  are secured into the IMD  10 . In still further alternative embodiments, the prongs  106  and the attachment points  108  on the IMD  10  may be switched. 
         [0067]    The prongs  106  and attachment points  108  may be any complimentary mating shapes or structures known to those in the art. Complimentary mating structures may include, for example, complimentary shaped snap fit or press fit connectors such as snaps, buttons, latches, balls and sockets, bayonet connectors, springs, etc. In further embodiments the connectors may simply be shaped structures that friction fit into a receptacle or may be spring connectors. The prongs  106  and attachment points  108  may operate such that the IMD  10  can be placed onto the suture ring  100  by pressing the IMD  10  onto the suture ring  100  with only the side wall of the pocket supporting the suture ring  100 . In one embodiment the friction connection between prongs  106  and attachment points  108  should not be so strong as to require the implanter to grasp or otherwise support the suture ring  100  during engagement. In still further embodiments, a loop or removable cord may be placed behind the suture ring  100  to provide additional support for snapping the IMD  10  to the suture ring  100 , after which time the cord may be removed by pulling it out. Increased functional connectivity between the IMD  10  and the suture ring  100  may present different issues with removing the IMD  10  from the suture ring  100  during explantation. Such issues may be overcome, however, with simply removing the suture ring  100  and the IMD  10  as one unit. 
         [0068]      FIGS. 7-11  illustrate further alternative embodiments of the suture ring  100 . In each figure, the various components are numbered utilizing the same number as is utilized in the original description of the suture ring  100  in  FIGS. 5A-C , but with a suffix of different letters indicative of the different figure. The numbering for  FIGS. 6A-C  include an ‘a’ to indicate that particular embodiment, while  FIGS. 7A-B  utilize a ‘b’ suffix,  FIGS. 8A-B  utilize a ‘c’ suffix, etc. 
         [0069]      FIGS. 6A-C  illustrate another embodiment of a suture ring  100   a . The suture ring  100   a  includes a suture body  102   a . The suture ring  100   a  includes female connectors  120   a  that operably engage corresponding attachment points  108   a  disposed on an outer bottom edge  100  of the housing  14  of the IMD  10 . The female connectors  120   a  may be snap fit connectors or other type of engagement members known in the art. As illustrated, the female connectors  120   a  are channels in the body member  102   a . When the IMD  10  is placed in the correct orientation, the attachment points  108   a  access the channel of the female connector  120   a  through an opening. The IMD  10  can then be secured into the connectors  120   a  by twisting the IMD  10  to lockingly engage the attachment points  108   a  to the connectors  120   a . As further described in relation to other embodiments above and below, the connectors  120  may have a number of different releasable locking mechanisms that secures the attachment points  108   a  when engaged. As illustrated, the attachment points  108   a  are substantially similar or the same as the prior suture loops discussed above. Designing the attachment points  108   a  in such a manner may give the person implanting the IMD  10  the choice to suture the IMD  10  directly into the cavity of the patient  23  or to utilize the suture ring  100   a.    
         [0070]    Suture ring  100   a  does not include suture holes  102 . Rather, the suture ring  100   a  includes a number of suture channels  124   a . The suture channels  124   a  are indentations in the suture ring  100   a  around which sutures are looped and tightened to secure the suture ring  100   a . The channels  124   a  are of a size and shape that will promote retention of the suture ring  100   a  in a desired position and prevents the suture ring  100   a  and the IMD  10  from spinning in the pocket. As may be appreciated, the channels  124   a  can be of a variety of sizes, depths, and shapes to help secure the sutures and, therefore the suture ring  100   a , in the desired position. 
         [0071]    The suture ring  100   a  may also include a cut out  122   a  formed into the suture body  102   a . Because the IMD  10  must be placed to a certain extent inside of the suture ring  100   a  for proper engagement of the connectors  120   a  and the corresponding attachment points  108   a , the cut out  122   a  may allow for the outlet  12  and the catheter  22  to not be pinched against the suture body  102   a.    
         [0072]    To secure IMD  10  to the suture loop  100   a  one or more sutures may be placed through the female connectors  120   a  and through the attachment points  108   a  of the IMD  10 . The sutures may be placed through the suture ring  100   a  through the female connectors  120   a , and more specifically through the small half circles  121   a , to secure the IMD  10  to the suture loop  100   a . As further explained below, in other embodiments a variety of different ways of securing the attachment points  108   a  to the female connectors  121   a  may be employed, including snaps, clips, sutures, etc. 
         [0073]    As illustrated in  FIGS. 7A-B , another alternative embodiment suture ring  100   b  includes a body member  102   b  with suture holes  104   b  in combination with female connectors  120   b . As previously discussed, the IMD  10  may include attachment points  108   b  that engage the female connectors  120   b  and rotationally engage the suture ring  100   b  to secure the IMD  10  in place. 
         [0074]    In another embodiment illustrated in  FIGS. 8A-B , the suture ring  100   c  may include a body member  102   c  with suture holes  104   c  in combination with a type of suture channel  124   c . In the present embodiment the suture channels  124   c  operate in tandem with the suture holes  104   c  to guide the sutures when securing the suture ring  100   c  in the body of a patient  23 . In other embodiments, the suture channels  124   c  may be positioned separately (not in alignment) with the suture holes  104   c  such that the user would have a choice in which to utilize during placement of the suture ring  100   c . The present embodiment further includes prongs  106   c  to lockingly engage with attachment points  108   c  on the IMD  10  to secure the IMD  10  to the suture ring  100   c.    
         [0075]      FIGS. 9A-B  illustrate another embodiment suture ring  100   d  that has a low profile width Dd. Though the body member  102   b  is narrow it can still secure the IMD  10  if made of a suitable material. The suture ring  100   d  further includes suture channels  124   d  and a cut out  122   d  to engage the catheter  22  and the outlet  12 . The suture ring  100   d  may engage the attachment points  108   d  using female connectors  120   d . The female connector  120   d  may have a prong, pawl, or other connector that flexes out of the way as the attachment point  108   d  is rotated through the female connector  120   d  or may also be secured using a suture as previously described. 
         [0076]      FIGS. 10A-B  illustrate another suture ring  100   e . Suture ring  100   e  includes elements as previously described, such as a body member  102   e , suture channels  124   e , and female connectors  120   e  that receive attachment points  108   e . In addition, suture ring  100   e  includes a locking tab  128   e . The locking tab  128   e  is a clip or other member that is generally biased in a downward direction. The locking tab  128   e  may have a pawl or other hook, joint, latch, seat, etc. that will engage the attachment point  108   e  of the IMD  10  when the attachment point  108   e  is rotated into operational engagement with the locking tab  128   e . The locking tab  128   e  then helps retain the IMD  10  in engagement with the suture ring  100   e . The locking tab  128   e  is shown as only being present on one of the connectors  120   e  but in alternative embodiments may be present on one or more of the connectors  120   e . During removal, the locking tab  128   e  may be lifted up with a specialized tool or a general surgical instrument or may simply release when enough rotational force is placed on the IMD  10  it disengage the pawl or other hook, joint, latch, seat, etc. 
         [0077]      FIGS. 11A-C  illustrate yet another embodiment of suture ring  100   f . Suture ring  100   f  includes elements previously described, such as a body member  102   f , suture channels  124   f , and connectors  120   f  that receive attachment points  108   f . In addition, suture ring  100   f  includes at least one connector  120   f  with a slot  132   f  that receives a pin  130   f . The pin  130   f  also includes a head  134   f  and a finger  136   f.    
         [0078]    In one embodiment, before placement of the IMD  10  onto the suture ring  100   f , the pin  130   f  is inserted through a bottom side of the suture ring  100   f  and partially into the slot  132   f . (The pin  130   f  may be positioned partially through the bottom side of the suture ring  100   f  before the suture ring  100   f  is sutured into the cavity to avoid difficulty in insertion after the suture ring  100   f  is sutured into position.) Once the IMD  10  is placed and rotated into position such that the attachment points  108   f  engage the connectors  120   f , the pin  130   f  may be inserted fully through a receptacle in the attachment point  108   f  to secure the IMD  10 . In addition, the finger  136   f  of the pin  130   f  may be snapped, fitted, or otherwise secured to the connector  120   f  or the body member  102   f  to prevent the pin  130   f  from “backing out” of the slot  132   f  and releasing the attachment member  108   f . The pin  130   f  secures the attachment point  108   f  in place and therefore helps to secure the IMD  10  to the suture ring  100   f  in the desired position. In further embodiments the pin  130   f  may be inserted from a top down orientation into the slot  132   f  and secured in a number of different ways to prevent it from releasing the attachment point  108   f.    
         [0079]    As may be appreciated, any combination of the described suture holes  104 , prongs  106 , attachment points  108 , guides  109 , cut out  12 , suture channel  124 , female connectors  120 , locking tabs  128   f  or pins  130   f  and slots  132   f  may be utilized to form a suture ring  100  without deviating from the scope of the present invention. 
         [0080]    In further embodiments, the suture ring  100  may also be designed to promote tissue in-growth after implantation of the IMD  10 . Tissue in-growth may further secure the IMD  10  in the implant pocket and reduce surgical revisions that may be necessary to correct a flipped or migrated IMD  10 . 
         [0081]    In further embodiments the suture ring  100  may incorporate radiopaque materials in order to be visible through standard imaging methods. 
         [0082]    In further embodiments, the suture ring  100  may also provide a platform for dispensing a therapeutic agent. Such materials may include antibiotic, antiviral, antiseptic, anti-infective, or other therapeutic agents or pharmaceuticals that can be eluted from a polymer or other material incorporated into the suture ring  100 . Such materials may help to reduce infections or other physiological reactions after the IMD  10  is implanted. In further embodiments, the suture ring  100  may incorporate a pouch or other pocket that allows for a desired material to be loaded into the suture ring  100  before placement by the clinician. As may be appreciated, the location of the pocket should not interfere with the primary purpose of providing an area to secure the IMD  10  during implantation. Further, the therapeutic agent should be selected to be compatible with the material forming the suture ring  100 . 
         [0083]    In further embodiments, a specialized tool or other instrument may be used to secure the attachment point  108  to the prong  106  and also be used to remove the attachment point  108  from the prong  106  during removal of the IMD  10 . In such instances, the attachment point  108  and prong  106  may be a variety of corresponding locking structures that can be fastened. 
         [0084]    While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing exemplary embodiments of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.