Abstract:
Multiple seals, internal to a connector block, provide for connecting an implantable medical device and an implanted cable or lead. The forces to engage sealing or releasing the seal are derived from a mechanism so they can be relaxed to permit ease of insertion or withdrawal of a lead, or can be increased to tightly seal against fluid migration, and to provide an electrical insulation between adjacent conductors of the lead and connector block. During implant of the medical device, the lead is inserted and a shaft is rotated with a tool to engage the seals. Later, the seals can be released by rotating the control shaft in the opposite direction to allow extraction of the lead from the connector block. The seals therefore are able to provide improved sealing without increasing the insertion or the extraction forces for the lead.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation-in-part (“CIP”) application of U.S. application Ser. No. 12/061,246, filed Apr. 2, 2008, entitled “A Stackable Electrical Connection Apparatus”, which claims benefit under 35 U.S.C. §119(e) to U.S. Ser. No. 60/915,765, entitled “Electrical Connection Apparatus”, filed May 3, 2007, and this application claims priority to U.S. Application No. 61/242,460, entitled “Electrical Barrier and Moisture Seal for an Implanted Medical Device,” filed Sep. 15, 2009. The content of each application is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    Disclosed herein are apparatuses for connecting a lead or catheter to an implantable medical device, and in particular, are connecting apparatuses for isolating and protecting the conductive components of the lead or catheter from body or other fluids. 
       BACKGROUND 
       [0003]    Active medical devices for delivering stimulation therapy to body organs such as the heart, brain, or other tissues are typically comprised of two major components. One component is an electronic circuit and power source, typically a battery, housed in a hermetically sealed container, often referred to as the implantable pulse generator (IPG), or as the “can”. The container includes feed-throughs allowing electrical signals and power to pass through the hermetic containment in and out of the circuitry to the second major component, the lead. This lead carries electrical signals from the IPG to the target body tissue in order to deliver therapy. The lead may also house conductors that carry signals generated by the human body back to the IPG. 
         [0004]    The connection between the IPG and the lead is made in a so called “connector block” or also known as a “header”, which is attached to the body of the IPG. The connector block is commonly formed from plastic or other materials. It houses the structures to electrically connect the lead&#39;s conductors to the corresponding contacts in the connector block. The connector block also has structures that mechanically secure the lead so that it does not move once it is secured. Providing a connector block facilitates the establishment and maintenance of a stable, low noise electrical connection between the IPG and the leads. In addition to providing the electrical connection between devices, connector blocks may include sealing components that provide isolation between electrical contact structures. However, some apparatuses for providing an electrical connection may not physically lock the connection in place or may not secure the lead position to an extent desired. For example, some leads may be loosely fitted on or in an electrical connection apparatus, and as a result, forces exerted on the lead such as pulling or twisting forces associated with muscle movement, etc. may cause the lead to loosen, create increased signal noise or completely disconnect from the electrical connection apparatus. 
         [0005]    In addition, the conductors within the lead are exposed at electrode sites on the distal end of the lead and interface by direct contact with body tissues. At the proximal end of the lead, the conductors are again exposed. Various forms of metallic rings, or segments, or end protruding pins are used to make the conductors available at the outer surface of the lead. The proximal end of the lead is inserted into the receptacle of the IPG and the lead&#39;s conductors are aligned with mating conductive surfaces inside the receptacle. 
         [0006]    The human body is a hostile environment to implanted medical devices and materials. Conductive, corrosive or otherwise interfering body fluids can compromise the insulation between conductors in the connector block. Thus, long-term implanted connections have seals incorporated into either the body of the lead, or in the structure of the connector block. The seals perform two related functions. The seals are a barrier to the intrusion of body or other fluids while the device is chronically implanted subcutaneously. In the absence of seals these fluids may migrate by various methods, such as capillary action, to the internals of the receptacle. The seals also separate any existing fluids that may have migrated into the connector block during implantation surgery, or thereafter, by making a tight and insulatory fit between the outer surface of the lead and the walls of the lumen in the connector block shaped to be a receptacle for the proximal end of the lead. 
         [0007]    There are two competing requirements for the seals. A tight seal is needed in order to prevent moisture migration; but must not cause frictional or inertial forces that prevent the insertion of the proximal end of the lead into the receptacle of the connector block. Typically, the requirement for reasonable forces to both insert and to withdraw the lead means both the moisture control attributes of the seals and the electrical insulating properties must be compromised. 
         [0008]    Accordingly, there is a need to provide an electrical connection apparatus that couples to implantable leads and that provides sealing properties that block undesirable fluids from entering the electrical connection apparatus. 
       SUMMARY 
       [0009]    Provided herein is an active implanted medical device having both enhanced moisture barrier properties and electrical insulatory properties of seals incorporated into the body of the receptacle of the active implanted medical device. 
         [0010]    Multiple seals, internal to a connector block or electrical connection apparatus, provide for sealing the implantable medical device and an implanted cable or lead. The forces to engage sealing or releasing the seal are derived from a mechanism so they can be relaxed to permit ease of insertion or withdrawal of a lead, or can be increased to tightly seal against fluid migration, and to provide an electrical insulation between adjacent conductors of the lead and connector block. During implant of the medical device, the lead is inserted and a shaft may be rotated with a tool to tighten a cinch around the seals. The seals may be released by rotating the control shaft in the opposite direction to loosen the cinch and allow extraction of the lead from the connector block. The seals therefore are able to provide improved sealing without increasing the insertion or the extraction forces for the lead. Other methods of mechanical engagement may also be used. The shaft which rotates and engages the seals may be the same shaft that engages the electrical contacts in the device, or the shaft may be dedicated to the seals. Additionally, where the connector block accommodates more than one lead, a common shaft may engage all contacts and seals simultaneously, or a shaft may be dedicated to each lead. 
         [0011]    In particular, connector blocks may establish the connections by using eccentric shafts and contacts configured to allow an engaging or latching of the lead into the connector block. 
         [0012]    According to certain embodiments, an electrical connection apparatus includes at least one stackable block operably coupleable to another stackable block, at least one pin receiving portion defined by an inner wall within the stackable block, at least one electrical connection contact having a first portion disposed within the at least one pin receiving portion of the at least one stackable block for receiving a pin, and a second portion disposed at a location exterior to the stackable block, where the first portion and the second portion integrally form the at least one electrical connection contact, and a fluid seal arranged in the stackable block adjacent to the electrical connection contact. The fluid seal includes a seal tube defining a pin receiving portion for receiving the lead pin and a cinch for reducing the diameter of the seal tube around the pin. When the diameter of the seal tube is reduced around a diameter of the pin, the seal tube fluidly isolates the at least one electrical connection contact associated with one stackable block from another electrical connection contact associated with the another stackable block. 
         [0013]    In other embodiments, an electrical connection apparatus includes a plurality of stackable blocks operably coupleable to each other, at least one pin receiving portion defined by an inner wall within one of the plurality of stackable blocks, at least one electrical connection contact with a first portion arranged in the at least one pin receiving portion of the one stackable block and for receiving a pin, and a second portion disposed at a location exterior to the one stackable block, where the first portion and the second portion integrally form the at least one electrical connection contact, and a fluid seal arranged in another of the plurality of stackable blocks. The fluid seal includes a seal tube defining a pin receiving portion for receiving the lead pin, and a cinch for reducing the diameter of the seal tube around the pin. When the diameter of the seal tube is reduced around a diameter of the pin, the seal tube fluidly isolates the at least one electrical connection contact associated with the one stackable block from the another stackable block having the fluid seal. 
         [0014]    While multiple embodiments of the present invention are disclosed herein, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, by those of ordinary skill in the art upon reading the following disclosure, the invention is capable of modifications in various aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0015]      FIG. 1  is cutaway view of one embodiment of an electrical connection apparatus. 
           [0016]      FIGS. 2A-B  depict a first side and a second side of a connector block. 
           [0017]      FIGS. 3A-B  depict electrical connection contacts according to certain implementations. 
           [0018]      FIGS. 4A-B  depict a first and second side of a connector block with four electrical connection contacts according to certain implementations. 
           [0019]      FIGS. 5A-5F  depict additional embodiments of electrical connection contacts. 
           [0020]      FIG. 6  depicts a seal component according to certain implementations. 
           [0021]      FIG. 7  depicts a seal component according to another implementation. 
           [0022]      FIGS. 8A-8D  depict additional embodiments of seal components. 
           [0023]      FIG. 9  depicts an alternative embodiment of an electrical connection apparatus having stackable connector blocks. 
           [0024]      FIG. 10  depicts an electrical connection apparatus according to another implementation. 
           [0025]      FIGS. 11A-C  depict a block of the apparatus depicted in  FIG. 10 . 
           [0026]      FIGS. 12A-B  depict a first and second sides of a cam component. 
           [0027]      FIG. 13  depicts a cross-sectional view of the an electrical connection apparatus according to an alternative configuration. 
           [0028]      FIGS. 14A-B  depict a first and second perspective view of another electrical connection apparatus according to certain implementations. 
           [0029]      FIGS. 15A-F  depict perspective views of a first and second side of a first end block, a stackable block and a second end block of the apparatus of  FIGS. 14A-B . 
           [0030]      FIGS. 16A-B  depict perspective views of a first and second side of a stackable block with a segmented contacting pin in place. 
           [0031]      FIGS. 17A-B  depict perspective views of the slider and contact in both the insertion and contact position relative to the pin. 
           [0032]      FIGS. 18A-B  depict perspective views of a first and second side of a cam according to certain implementations. 
           [0033]      FIGS. 19A-B  depict perspective views of electrical connection contacts for use on a left and a right side of the stackable block. 
           [0034]      FIGS. 20A-B  depict perspective views of a first and second side of a slider for use with the stackable block. 
           [0035]      FIGS. 21A-B  depict perspective views of a first and second side of the stackable block with a seal plate. 
           [0036]      FIGS. 22A-B  depict perspective views of a first and second side of the seal plate depicted in  FIGS. 21A-B . 
           [0037]      FIGS. 23A-B  depict perspective views of a first and second perspective view of another electrical connection apparatus having a two pin configuration. 
           [0038]      FIG. 24  is a flowchart of a method for electrically connecting an implanted medical device and an implanted stimulation electrode according to the present invention. 
           [0039]      FIG. 25  is an isometric view of an active seal, according to certain embodiments. 
           [0040]      FIG. 26  depicts a proximal end of an implanted lead. 
           [0041]      FIG. 27A  is an isometric view of a two lumen active seal incorporating a controlling mechanism, according to certain embodiments. 
           [0042]      FIG. 27B  is a magnified view of the active seal mechanism, according to certain embodiments. 
           [0043]      FIG. 27C  is a magnified view of the active seal mechanism with the cam rotated to the latched position. 
           [0044]      FIG. 28  is a cross-sectional view of a connector block assembly for an implantable device, according to certain embodiments. 
           [0045]      FIG. 29  is a schematic view of an alternative method of operating the seal 
       
    
    
     DETAILED DESCRIPTION 
       [0046]    The present invention, according to one embodiment, is an electrical connection apparatus. 
         [0047]    In one aspect, an electrical connection apparatus may be used in conjunction with implantable medical devices such as neurostimulators or pacemakers. For example, such an apparatus may be used to provide an electrical connection between the implanted device and an implanted stimulation electrode. In one embodiment, the implanted device is a pacemaker. Alternatively, the implanted device may be an implantable cardioverter defibrillator (“ICD”), an implantable pulse generator, or any other implanted device requiring an electrical connection. 
         [0048]      FIG. 1  is a cutaway view of one embodiment of an electrical connection apparatus  10 . The apparatus is comprised of stackable blocks  12  operably connected in a stacked fashion, with end blocks  14 ,  16  disposed at each end. Each block  12 ,  14 ,  16  defines pin receiving portions  18  configured to receive a pin such as pin  20  depicted in  FIG. 1 . In addition, a seal component  22  is disposed between each block  12 , 14 , 16 . Each block  12 , in this implementation, also has electrical connection contacts  24  having exterior contact points  26  (also referred to herein as “leads”) disposed on an exterior portion of the device  10  and integrally formed C-shaped interior contact portions  28  disposed within the pin receiving portions  18 . 
         [0049]    Generally, the connection apparatus  10  depicted in  FIG. 1  connects two devices or components in the following fashion. The pin  20 , which is electrically coupled to one device via the lead wires  30 , is positioned in one of the pin receiving portions  18  and thereby contacts one or more of the interior contact portions  28  of the electrical connection contacts  24 . The other device is positioned or configured such that it is in electrical contact with one more of the exterior contact portions  26  of the electrical connection contacts  24 . Thus, the two devices are electrically coupled to each other via the electrical connections contacts  24  disposed within each block  12  of the apparatus  10 . 
         [0050]    In the embodiment depicted in  FIG. 1 , the apparatus  10  has eight connector blocks  12 . However, it is understood that the apparatus  10  may be comprised of one block  12 , two blocks  12 , or any number of blocks  12  in order to provide a connection device  10  with the desired size and configuration. End blocks  14 ,  16  may be used as the end termination for each end of the electrical apparatus  10 . End block  14  is also referred to herein as an “insertion end block,” while end block  16  is also referred to herein as an “end cap block.” The blocks  14 ,  16  may be manufactured out of metals such as titanium, stainless steel or other biocompatible metals or metallic alloys. Alternatively, the blocks  12 ,  14 ,  16  may be made of biocompatible thermoset or thermoplastic resins, or any other known biocompatible material for use in connection devices 
         [0051]    According to the implementation depicted in  FIG. 1 , the insertion end block  14  defines mechanical fastening ports  32  for each of the pins  20 . Each port  32  may be configured to be in communication with one of the pin receiving portions  18  such that each port  32  may receive a fastening component (not shown) that may be used to fasten or otherwise secure the pin  20  into its position in that pin receiving portion  18 . In one embodiment, the fastening component is a threaded set screw made from biocompatible material and each port  32  is a threaded hole configured to receive such a set screw. Alternatively, any known fastening component may be incorporated into the insertion end block  14 . In one implementation, a cap or other type of cover may be provided and positioned over the fastening port  32 , thereby presenting a relatively smooth external profile for the device  10 . In a further alternative, the insertion end block  14  has no fastening ports or fastening components, and the pin  20  is at least partially secured within the pin receiving portions via frictional forces created by contact with the C-shaped contact portions  28 . 
         [0052]    In use, and in accordance with one aspect, after the pin  20  is positioned in the pin receiving portion  18 , the set screw is threaded into the port  32  such that the set screw contacts the pin  20  at an electrically isolated portion of pin  20 , and secures pin  20  in the pin receiving portions  18 . It acts to supplement the frictional forces exerted by the C-shaped contact portions  28  and helps prevent outward migration of the pin from the housing caused by vibration or excessive tensile or torsional forces on the pin  20  or lead wires  30  during use. 
         [0053]    In one implementation as shown in  FIG. 1 , pin  20  has electrically-isolated circumferential contacts  34  distributed along its length. When the pin  20  is positioned in a pin receiving portion  18 , each of the circumferential contacts  34  are positioned to correspond with and contact a C-shaped contact portion  28 . Each circumferential contact  34  is electrically connected to one of the lead wires  30 , each of which is embedded in the pin  20 . Each individual wire or lead  30  may be potted within the pin  20  and may be electrically isolated and insulated from other leads. The pin  20  may contain one or more separate isolated lead wires  30  for each contact  34 . Each wire  30  may be capable of maintaining signal integrity from the circumferential contact area  34  through the wire  30  and to a desired location within the body, such as a target tissue, nerve, or some other target area. In one embodiment, a wire  30  terminates with a specialized electrode (not shown) to improve signal delivery to the desired location. 
         [0054]    The configuration of a connector block  12  with electrical connection contacts  24 , according to one embodiment, is shown in  FIGS. 2A ,  2 B,  3 ,  4 A, and  4 B.  FIGS. 2A and 2B  depict both sides of a connector block  12  without electrical connection contacts, with  FIG. 2A  depicting a first side and  FIG. 2B  depicting a second side. The block  12  has a housing  40  that defines the pin receiving portions  18  and further defines slots or passages  42  in which portions of the electrical connection contacts may be disposed. 
         [0055]      FIG. 3  depicts an electrical connection contact  24 , in accordance with one implementation. The electrical connection contact  24  in this embodiment has a C-shaped contact portion  28  and an external lead portion  26 . The contact portion  28  and lead portion  26  are connected via the link portion  44 . In one embodiment as shown in  FIG. 3 , the C-shaped contact portion  28  defines slots or gaps. Alternatively, the contact portion  28  is a continuous, solid component with no slots or gaps. 
         [0056]      FIGS. 4A and 4B  depict a first and second of connector block  12  with four electrical connection contacts  24 , according to certain embodiments. Each electrical connection contact  24  may be positioned such that the C-shaped interior contact portion  28  is disposed within a pin receiving portion  18 , the exterior contact portion  26  may be disposed on an exterior portion of the housing  40 , and the link portion  44  may be disposed in one of the slots  42  as discussed above with respect to  FIGS. 2A and 2B . 
         [0057]    Each of the contact portions  28 , according to one embodiment, is configured to contact any pin positioned in the pin receiving portion  18 . In one embodiment, each contact portion  28  contacts a corresponding pin contact area  34  on the pin  20 . Such contact results in an electrical connection between the lead  30  and the exterior contact points  26 , via the electrical path from the lead  30  to the pin contact area  34  to the contact portion  28  to the link portion  44  to the exterior contact portion  26 . 
         [0058]    In accordance with one implementation, each C-shaped contact portion  28  is configured to have elastic properties and to have an unconstrained diameter (also referred to as its “unconstrained position,” “natural position,” “starting position,” or “original position”) that is smaller than the outside diameter (“OD”) of the pin  20 . “Elastic properties” as used herein means capable of recovering shape after deformation. Thus, when a pin  20  is positioned in the pin receiving portion  18 , the contact portion  28  is deformed from its unconstrained diameter to a larger diameter that accommodates the pin  20 . The elasticity of the contact portion  28  urges it back toward its unconstrained diameter such that the contact portion  28  is forced into contact with the pin  20  and results in a normal force being exerted across the contact interface. According to one embodiment, the contact portion  28  is forced into contact with a circumferential contact portion  34  on the pin  20 . When the pin  20  is removed, the elastic properties of the contact portion  28  cause the contact portion  28  to return to its unconstrained diameter. 
         [0059]    In another embodiment, the C-shaped contact portion  28  also has a maximum diameter that is limited by the diameter of the pin receiving portion  18 . That is, the contact portion  28  may only expand to its maximum diameter, at which diameter the contact portion  28  is in contact with the walls of the pin receiving portion  18  and cannot expand further. 
         [0060]      FIGS. 5A-5F  depict additional embodiments of electrical connection contacts. 
         [0061]    According to one embodiment, the electrical connection contacts are made out of a precious metal. For example, the contacts may be constructed of a platinum or PGM (Platinum Group Metal) alloy such as, but not limited to, Pt-10% Ir, Pt-20% Ir, Pt-8% W, Paliney® 500, Paliney® 1100, or Paliney® 1200. Alternatively, the contacts may be formed out of a base metal such as a copper alloy or stainless steel that is overplated with an appropriate electrically and environmentally stable contact material such as Au, Pt, Pd, Pd—Ni, etc. It is also envisioned that the overplate might cover the entire connection  24  or just the terminal contacts  26 ,  28 . According to one embodiment, one advantage of precious metal contact surfaces in comparison to other conductive materials is that the precious metal contact surfaces are capable of maintaining stable electrical signal integrity at reduced force levels. This results in reduced force requirements at the mating of the contact portion  28  and the pin  20 , thereby allowing for greater design flexibility in selecting the spring characteristics of the contact member  28 . Alternatively, the electrical connection contacts may be made out of a non-PGM metal such as stainless steel, niobium, tantalum, MP35N, or other such non-PGM metals. Certain of these non-PGM metals may require higher contact forces to maintain a stable interface, which may be accomplished by selecting a material with a higher elastic modulus and/or a higher yield stress or by increasing the thickness of the spring member. 
         [0062]    The seal component  22 , as depicted in  FIG. 1  according to one embodiment, is configured to be disposed between any two blocks (including the end blocks) and operates to create two seals. The first seal is a seal between the pin  20  and the rest of the block  12 . The second seal is a seal between two connected blocks  12  and associated pin contact areas  34 . 
         [0063]      FIGS. 6 and 7  depict a seal component  22 , according to another embodiment. In the embodiment depicted in  FIG. 6 , a seal plate  50  having four seal components  22  is positioned on one side of a connector block  12 . Each seal component  22  disposed in the plate  50  has a “vertical” seal  52  and a “horizontal” seal  54  that completely encircle the pin  20  receiving portion  18  of the block  12 . The terms “vertical” and “horizontal” are used solely to describe the seals with respect to each other and the connector blocks and are not intended to be limiting. It is understood that the vertical seal  52  could also be positioned horizontally and that the horizontal seal  54  could also be positioned vertically, depending on the disposition of the entire block. The combination of seals  52  and  54  result in a t-shaped seal component. 
         [0064]    As best shown in  FIG. 7 , the vertical seal  52  of seal component  22  arranged in seal plate  50  provides a seal between the pin receiving portion  18  and the areas exterior to the pin receiving portion  18 . In one embodiment, one end  56  of the vertical seal  52  contacts the block  12  next to which the plate  50  has been positioned and the other end  58  of the seal  52  contacts the adjacent block  14 . According to one embodiment, the vertical seal  52  may form a seal that prevents body fluids from entering into the pin receiving portion  18 , which may cause a short. In accordance with one implementation, the horizontal seal  54  of seal component  22  contacts any pin positioned in the pin receiving portion  18  and thereby provides a seal in the pin receiving portion  18  between blocks  12  and  14 . As depicted by the positioning of seal plates  50  in  FIG. 7 , and in view of the discussion above, it should be understood that seal plate  50  may also be provided between adjacent stackable blocks  12  and between blocks  12  and  16 . 
         [0065]      FIGS. 8A-8D  depict additional embodiments of seal components. As shown in  FIG. 8C , certain seal plates define a central opening  60 . In certain embodiments, this central opening  60  may define a portion of a bolt shaft configured to receive a rotating cam or an assembly bolt, both of which are described below. Alternatively, certain seal plate embodiments such as that depicted in  FIG. 8D  have no central opening. 
         [0066]    In one embodiment, a seal component is made out of biocompatible, compliant thermoset or thermoplastic polymer, such as, but not limited to, a silicone rubber. Alternatively, the seal component may be made of any known compliant biocompatible material that may be used for providing a seal in a medical device. 
         [0067]      FIG. 9  depicts an alternative embodiment of a connector apparatus  80  having stackable connector blocks  82 . In this embodiment, each block  82  has a D-shaped configuration and defines nine pin receiving portions  84 . Alternatively, the block  82  may define any number of pin receiving portions that will fit on the block  82  and operate to provide an electrical connection. It is understood that the blocks  82  and pin receiving portions  84  may also have any other configuration. That is, the blocks  82  might be formed in another shape and/or the pin receiving portions  84  might be arranged in any other configuration on the blocks  82 . It is also understood that any of these alternative embodiments could incorporate any of the various components described herein. 
         [0068]    In a further alternative, the stackable blocks are secured in another fashion. That is, according to one embodiment, in the absence of the cam assembly, the blocks may be secured via a bolt that is disposed through a central hole in each of the stackable blocks  12  and the insertion end block  14 . One example of such a central hole  60  is depicted in  FIG. 8C . According to one embodiment, the bolt may be secured to the end block  16  via a mating feature. For example, the bolt may have a threaded end that mates with a threaded hole in the end block  16 . Alternatively, any known components for securing such a bolt to an end block may be used. The bolt may be fabricated from a high strength biocompatible material such as stainless steel, a titanium alloy, a Co—Cr alloy such as MP35N, an Inconel alloy, or any other known high strength biocompatible material. In one implementation, the proximal portion of the bolt has a drive mechanism to allow for proper tightening on the assembly and may also have an over cap to minimize potential exposed surface crevices after assembly. In one embodiment, the bolt is the only feature for securing the blocks together. Alternatively, the bolt may be used in conjunction with the external clip  110 . 
         [0069]      FIG. 10  depicts an electrical connection apparatus  100 , according to another embodiment. This apparatus  100  provides for easy insertion and removal of contact pins. The apparatus  100  has four pin receiving portions  104  defined within the blocks  102  of the apparatus  100 . As discussed above with the embodiment depicted in  FIG. 1 , the pin receiving portions  104  are disposed through almost the entire length of the device  100 . A pin (not shown) may be inserted into each of the pin receiving portions  104  and once activated, will be placed in contact with each of the C-shaped contact points  108  (see  FIG. 11A ) as described below. As in the previous embodiment depicted in  FIG. 1 , each pin has internal wires or leads that are electrically connected to the circumferential contact areas of the pin, similar to areas  34  as shown in shown in  FIG. 1 . 
         [0070]      FIG. 10  also depicts one embodiment for securing the stackable blocks  102 . That is, the blocks  102  are secured with an external clip  110  that connects the end cap block  16  to the insertion end block  14 . In one implementation, the clip  110  is a single U-shaped spring that has two ends. The first end is secured at a first attachment point  109  on the end block and the second end is secured at a second attachment point  111 . The length of the U-shaped clip  110  runs along the outside of the device  100  and wraps around the other end block along a channel defined in the other end block, thereby securing the stackable blocks  102  together. Alternatively, the external clip  110  may be two C-shaped clips, each having a hook-like feature at each end of the clip. In this embodiment, there are two attachment points in each end block (instead of just one end block as shown in  FIG. 10 ) such that one C-shaped clip  110  is disposed on one exterior side of the connector  100  and the other C-shaped clip is disposed on the opposite side and both are attached to the end blocks with the hook feature. 
         [0071]      FIG. 11A  depicts a block  102  of the apparatus depicted in  FIG. 10 . Like the blocks depicted in  FIGS. 4A and 4B , block  102  has C-shaped contact portions  108  disposed within pin receiving portions  104 . However, the C-shaped contact portions  108  in this embodiment differ from the C-shaped contact portions  28  described above with respect to  FIGS. 3 ,  4 A, and  4 B. More specifically, the C-shaped contact portions  108  do not have an unconstrained diameter that is smaller than the OD of the pin. To the contrary, the natural configuration of the C-shaped contact portions  108  in this embodiment have a diameter that is greater than the OD of the pin. 
         [0072]    In addition, the block  102  has a cam component  112  disposed in a central portion of the block  102  such that the cam component  112  is in contact with each of the pin receiving portions  104 . The cam component  112 , which is depicted in further detail according to one embodiment in  FIGS. 12A and 12B  (which depict both sides of a cam component  112 ), has four indentations  114  and four contact portions  116  around the circumference of the component  112 . In addition, the component  112  has a drive receiving component  118  on one side as shown in  FIG. 12B  and drive component  120  on the other side as shown in  FIG. 12A . According to one embodiment, the drive receiving component  118  is an inset hexagon  118  and the drive component  120  is a coupleable hexagon drive component  120 . 
         [0073]    Each block  102  in this embodiment has a similar cam component  112  such that when the blocks  102  are connected to each other, the drive components  120  of each cam component  112  are inserted into the adjacent drive receiving component  118  on the adjacent block  102 , thereby resulting in each of the cam components  112  in each of the blocks  102  being connected. In this embodiment, the connected cam components  112  may be turned using a tool  122  depicted in  FIG. 13 , e.g., a wrench such as a torque wrench. 
         [0074]    According to the electrical connection apparatus  100  depicted in  FIG. 13 , the tool  122  is inserted through a central hole  124  defined in the end block  14  and positioned into the drive receiving component  118  of the cam component  112  of the block  102  connected to the end block  14 , whereby the tool  122  may be used to turn the connected cam components  112 . 
         [0075]    In one embodiment, the tool  122  has on its distal end  126  (the end that contacts the drive receiving component  118 ) certain features that may improve torque transmission. According to one embodiment, the feature may be a shaped end (such as a hexagonal shape, for instance) that is engageable with the drive receiving feature  118  of the cam  112 . Additionally, in one implementation, the proximal end  127  of the tool  122  may have screw drive features (such as slots, hex, torx, etc.), external knurling, increased circumference flange, or any other known features for improving torque transmission. In one implementation, the proximal end  127  of tool  122  is configured as a hex driver. 
         [0076]    As best depicted in both  FIGS. 11A-C , it is understood that the configuration of blocks  102  is slightly different from the blocks depicted in  FIGS. 4A and 4B . That is, the slots in blocks  102  have a different configuration to accommodate the slightly different configuration of the electrical connection contacts. According to one embodiment, this configuration allows for a central hole defined in each of the assembly blocks  102 . 
         [0077]    In use, the cam component  112  provides for the easy insertion and removal of the pins. That is, when the cam component  112  is rotatably disposed such that the four indentations  114  are adjacent to the pin receiving portions  104  (the “insertion position”), each C-shaped contact portion  108  is disposed at its largest diameter, which is greater than the OD of a pin. Thus, when the cam component  112  is in the insertion position, a pin may easily be inserted into or removed from a pin receiving portion  104  while experiencing little or no frictional contact with the C-shaped contact portion  108 . Thus, the pin may be inserted or removed with little or no force. 
         [0078]    In contrast, when the cam component  112  is rotatably disposed such that the four contact portions  116  are adjacent to the pin receiving portions  104  and in contact with the C-shaped contact portions  108  (the “contact position”), each C-shaped contact portion  108  is urged into contact with the pin by the force of the contact portion  116  of the cam component  112 , thereby resulting in electrical contact between the C-shaped contact portion  108  and the pin. An example of the contact position is depicted in  FIG. 11A . In one embodiment, the C-shaped contact portion  108  is in electrical contact with the circumferential contact area of the pin similar to the contact area  34  depicted in  FIG. 1 . 
         [0079]    Thus, the tool  122  may be used to turn the connected cam components  112 , thereby moving the C-shaped contacts  108  between the insertion position and the contact position. That is, the tool  122  may be used to turn the cam components  112  such that the contact portions  116  are positioned in contact with the C-shaped contacts  108 , thereby urging them into contact with the pins. In addition to establishing a stable electrical contact interface between the C-shaped contacts  108  and the pin, the pressure of the C-shaped contacts  108  against the pin acts to prevent movement of the pin or otherwise secure the pin in its position within the pin receiving portion  104 . 
         [0080]    Further, the tool  122  may be used to turn the cam component  112  such that the four indentations  114  are in contact with the four C-shaped contacts  108 , thereby allowing each C-shaped contact  108  to expand and to return to the insertion/withdrawal position. 
         [0081]    In certain embodiments, after the cams  112  are set to the appropriate position, the tool  122  may be removed and replaced with a lower profile cap. Alternatively, no cap is provided. 
         [0082]    According to one implementation, the combined force of the C-shaped contacts  108  in contact with the pin creates a sufficiently large mechanical force on the pin such that the pin is not easily dislodged or otherwise disconnected via physical movement of the device  100  or pin. As such, the device  100  may withstand outside physical forces, including shaking, twisting, and/or other such forces, without disrupting the connection between the pins and the contact portions  108  as a result of the stable configuration of the contact adjustment component  112  and contact portions  108 . As an example, this stability may, in some embodiments, allow a patient requiring such a device  100  to be more physically active than is possible with known devices. In another embodiment, the apparatus  100  may also have a mechanical fastening port (not shown) similar to that described above with respect to  FIG. 1 , thereby providing further stability. 
         [0083]    In the embodiment shown in  FIG. 13 , an apparatus may provide a tactile response to rotation of the cam component  112  such that a user may properly position the cam component  112 . In one embodiment, the tactile response is provided by mated detent features disposed on the drive component  120  of the cam component  112  as shown in  FIG. 12A  and on the portion of that end block  16  that contacts the cam component  112  as shown in  FIG. 13 . More specifically, the drive component  120  has female detent features  130  shaped as hemispheres formed into the end of the component  120 . Further, the end block  16  has male detent features  132  shaped as hemispheres that may mate with the female detent features  130 . In use, as the cam component  112  is turned, the user may feel the mating and unmating of the detent features and thereby may easily determine the position of the cam component  112 . According to one embodiment, the detent features  130 ,  132  are positioned such that the features mate when the cam component  112  is positioned in the contact position, such that the tactile response of the detent features  130 ,  132  mating indicates to the user that the cam component  112  is in the contact position. 
         [0084]    In an alternative embodiment, a tactile response is achieved through a set of small indentations (not shown) disposed on the contact portions  116  of the cam component  112 . These indentations are much smaller and shallower than the indentations  114  and are placed at the optimal contact points  116  on the cam component  112 . These indentations provide a tactile response to the user, indicating that the cam component  112  is in the contact position. 
         [0085]    In a further embodiment, a visual method of positioning the cam component  112  is provided. In this embodiment, alignment markers are placed on the end block  14  and the top of the cam tool  122 . 
         [0086]      FIGS. 14A-B  depict a first and second perspective view of another electrical connection apparatus  210 , according to certain implementations. The electrical connection apparatus  210  includes stackable blocks  220  arranged between end blocks  240 ,  260 . The assembly of blocks  220 ,  240  and  260  may be held together by external spring clip  280  or by a U-shaped clip (not shown) with the terminal ends of the U-shaped clip terminating at end block  240 . Electrical connection apparatus  210  may connect two implantable components, e.g., leads and a medical device, in the manner discussed above in relation to the electrical connection apparatus  10  of  FIG. 1 . However, according to the presently described implementation, the electrical connection apparatus  210  is configured so that cam action is initiated from one end, e.g., the end corresponding to end block  240 , and pins enter from another end of apparatus  210 , e.g., the end corresponding to end block  260 . This embodiment may provide certain advantages because, due to the small allowable space for active implantable devices and the small sizing of the electrical connectors, placing leads at one end of the device and rotating the cam at the opposite end may reduce the chance of entanglement between the leads and the rotating mechanism, hands, tool, torque wrench, etc., during manual rotation or operation of the cam. 
         [0087]      FIGS. 15A-F  depict perspective views of a first and second side of a first end block  240 , a stackable block  220  and a second end block  260  of apparatus  210  shown in  FIGS. 14A-B . 
         [0088]    In  FIGS. 15A-B , end block  240  is configured with grooves  241  on opposite sides of the block for accommodating external clip  280 , an opening  242 , which provides access to a cam or other adjustment component (not shown) situated in an adjacent stackable block  220 , and receivers  243  for receiving retaining clips  222  arranged on stackable block  220  (shown in  FIG. 15C ). End block  240  serves as an access point for accessing a cam or other adjustment component arranged on the interior of the assembled apparatus  210  and may have a configuration similar to insertion end block  14  of  FIG. 1 , except that end block  240  does not include the pin receiving portions described in relation to  FIG. 1 . 
         [0089]      FIGS. 15C-D  depict perspective views of a first and second side of a stackable block  220 . In  FIGS. 15C-D , block  220  includes grooves  221 , retaining clip  222 , receivers  222 ′ for retaining clips  222 , knife edges  223 , slots  224 , potting pockets  225 , cam receiving portion  226 , cam detents  227 , cam hard stops  228  and pin receiving portions  229 . Grooves  221  on opposite sides of the block accommodate spring clip  280  and may facilitate maintaining the desired positioning of spring clip  280  on the assembled apparatus  210 . Retaining clips  222  arranged near the periphery of an interior facing portion of block  220  may facilitate holding seals  250  in place (See  FIG. 21A ) and may aid in assembly of adjacent blocks, e.g., adjacent end blocks  240 ,  260  or other stackable blocks  220 . For example, during assembly, retaining clips  222  may engage with receivers  222 ′ arranged near the periphery of an interior facing portion of another block  220  or from receivers  243  arranged near the periphery of an interior facing portion of an adjacent end block  240 . Knife edges  223  provided on stackable blocks  220  may facilitate providing a seal between seal plate  250  and stackable blocks  220 . 
         [0090]    Each stackable block includes four slots  224  for providing an electrical connection contact (not shown) access to the exterior of the block  220 . Four potting pockets  225  are arranged in an area proximate the slot  224  and may accommodate an epoxy or other polymeric resin, which may seal slots  224  and prevent moisture ingress to the interior of apparatus  210 . Cam receiving portion  226  is defined by interior walls of stackable block  220  and is configured to receive a cam (not shown) or other adjustment component and includes cam hard stops  228  that cooperate with the cam  330  and serve as stop points for the cam rotating from a locking or contact to an unlocking or insertion position. Cam detents  227  are arranged adjacent the cam hard stops  228  and serve as an indicator to a user rotating the cam that the cam has reached a locking or contact position or an unlocking or insertion position. Four pin receiving portions  229  are each configured to accept a pin (not shown) and are defined by interior walls of stackable block  220 . 
         [0091]      FIGS. 15E-F  depict perspective views of a first and second side of a second end block  260 , which may be configured similar to end cap block  16  described in relation to  FIG. 1 , except that end block  260  may include pin receiving portions and/or fastening ports similar to those provided in insertion end block  14 . End block  260  also includes a groove  261  for accommodating external spring clip  280  or a U-shaped spring that would traverse exterior of the second end block along the length of the groove. 
         [0092]      FIGS. 16A-B  depict perspective views of a first and second side of the stackable block  220  with a pin  300  inserted through the block.  FIG. 16A  depicts a drive component of cam  330  in an insertion position.  FIG. 16B  depicts the assembly from the back side and the cam  330  with the drive receiving component is set in the open or initial insertion position. 
         [0093]      FIG. 17A  depicts one of the contact assemblies in the unlocked position. The cam  330  is loosely coupled to a slider  350 , which is mechanically engaged to an electrical connection contact  340  via a tab  342  (see  FIG. 19A ). In the unlocked position, slider  350  is in a lowered position relative to the periphery of stackable block  220  and loosely engaged with electrical connection contact  340 . Electrical connection contact  340  is in a relaxed state, and as a result, pin  300  arranged in block  220  may be slidable through the C-shaped connection  346  in the contact  340 . Thus, in  FIG. 17A , the cam  330 , slider  350  and tab  342  are in an insertion position, and a pin may be inserted into or removed from a pin receiving portion  229  while experiencing little or no frictional contact with the C-shaped contact portion  346 , resulting in the pin being insertable or removable with little or with zero insertion force. 
         [0094]    In  FIG. 17B , a first side of the contact assembly is shown in its locked position. Cam  330  has raised the position of slider  350  and C-shaped contact portion  346  is clinched around pin  300  at an electrically-isolated circumferential contact  304 . As a result, when cam  330  is in a locked position, pin  300  is locked into position about its circumferential contact  304  by the reduction of the circumference of the C-shaped portion of electrical C-shaped contact  346 . This action completes the electrical path from the external contacts  344  through the C-shaped contact  346  to the isolated pin contact  304  to the internal pin lead  30  (see  FIG. 1 ). When four pins  300  are provided in apparatus  210 , each slider  350  is responsible for raising the position of two tabs  342 ,  362  (see  FIGS. 19A  and B), which in turns clinches two of the four pins  300 . Providing sliders  350  that engage with tabs  342 ,  362  to cause the C-shaped contacts  346  to tighten around and couple to pins  300  in response to cam action, according to the present implementation, may reduce or prevent buckling of the C-shaped portion  346 ,  366  of the electrical connection contacts  340 ,  360 . 
         [0095]    According to  FIG. 17B , in addition to establishing a stable electrical contact interface between the C-shaped contacts  346  and the pin  300 , the pressure of the C-shaped contacts  346  against pin  300 , due to the positioning of slider  350  in a contact position, may prevent movement of the pin or secure the pin in its position within the pin receiving portion  229 . The force of the C-shaped contact  346  in contact with the pin may provide a sufficiently large mechanical force on the pin such that the pin may not be dislodged or dislodged easily, or otherwise disconnected via physical movement of the device  210  or pin  300 . Thus, the device  210  may withstand outside physical forces, including shaking, twisting, and/or other such forces, without disrupting the connection between the pins and the contact portions  346  as a result of the stable configuration of the cam  330 , slider  350  and tab  342 . 
         [0096]      FIGS. 18A-B  depict perspective views of a first and second side of cam  330 . Cam  330  includes a drive component  331 , eccentric paths  332  for sliders  350 , detent feature  333  and a drive receiving component  334 . In  FIG. 18A , the drive component  331  having a tapered hexagonal male portion is configured such that it fits into an adjacent cam by way of a complementary drive receiving component  334  having a tapered hexagonal female receiving configuration. When cam  330  is arranged in block  220 , the drive component  331  protrudes beyond the an exterior surface of block  220 , see e.g.,  FIGS. 16A and 17A . Eccentric paths  332  for slider  350  may be configured so that when cam  330  is arranged in block  220 , eccentric paths  332  loosely couple to the sliders  350  when in an insertion or unlocked position, and moves sliders  350  up or down when in a contact or locked position. Detent feature  333  engages with cam detents  227  of block  220  when cam  330  is moved to either a locked or an unlocked position. When detent feature  333  reaches one of the cam detents  227 , a user exerting torque, e.g., by way of a tool such as a wrench or a torque wrench, on the cam assembly may feel detent feature  333  engage with the cam detent. Where a user continues to exert torque on the cam assembly after the detent feature  333  engages with cam detent, detent feature  333  may abut an adjacent cam of the pair of cam hard stops  228  provided on block  220  preventing cams from further rotational movement. In use, cams  330  from adjacent blocks  220  interlock via the drive and drive receiving components  331 ,  334 , respectively. Accordingly, actuation of a cam  330  arranged in a stackable block  220  adjacent to end block  240  results in actuation of each of the cams  330  arranged in the electrical connection apparatus  210 . Furthermore, because detents  227  and hard stops  228  in stackable block  220  cooperate with cam  330 , initiating cam action with a torque wrench may provide for precise engagement and rotation of cams  330  within electrical connection apparatus  110 . 
         [0097]      FIGS. 19A-B  depict perspective views of electrical connection contact  340 ,  360  for use on a left and a right side of the stackable block  220 .  FIGS. 20A-B  depict perspective views of a first and second side of a slider  350  for use with the stackable block  220  and include recesses  351  and  352  for engaging with electrical connection contact  340 ,  360 . According to certain implementations, sliders  350  may be constructed of plastic, ceramic, other insulating material, or may be coated with an insulating material. 
         [0098]    With reference to  FIG. 19A , a left side electrical connection contact  340  includes tab  342  for engaging with slider recess  351 , exterior contact portion  344  for contacting an external device and for aligning along an exterior length of the stackable block  220 , and C-shaped interior contact portion  346  for aligning with pin receiving portion  229  and for contacting pin  300 . In  FIG. 19B , a right side electrical connection contact  360  includes tab  362  configured for engaging with slider recess  351 , exterior contact portion  364  for contacting an external device, and C-shaped interior contact portion  366  for aligning with pin receiving portion  229  and contacting pin  300 . Tab  342 ,  362  provides slider recess  351  with a desirable length of the electrical connection contact  340 ,  360  such that the contact may be moved from an insertion to a contact position as a result of an upward or downward movement of the slider  350 . Electrical connection contacts  340 ,  360  may also include features described above in relation to the electrical connection contacts of  FIGS. 3A-B ,  5 A-G and  11 . 
         [0099]      FIGS. 21A-B  depict perspective views of a first and second side of the stackable block  220 .  FIGS. 22A-B  depict perspective views of a first and second side of a seal component  250 , which may be arranged on stackable block  220  at a position corresponding to the recessed portion R of seal block  220  depicted in  FIG. 21A . Assembled electrical connection apparatus  210  ( FIGS. 14A-B ) may be provided with a seal component  250  between each block, e.g. between end block  240  and stackable block  220 , between stackable blocks  220 , and between stackable block  220  and end block  260  in order to prevent biological fluids from contacting pins  300 , for example. In addition, stackable blocks  220  associated with the presently described apparatus  210  include clips  222 , which may facilitate holding seal component  250  in place as well as engage with receivers  222 ′, as shown in  FIG. 21B . Moreover, knife edges  223  provided on stackable block  220  in the areas corresponding to the cam receiving portion  226 , pin receiving portions  229 , and an area surrounding each of the cam and pin receiving portions. Knife edges  223  may mate with vertical seal portions provided on seal component, which are shown and described in relation to  FIG. 7 . 
         [0100]      FIGS. 23A-B  depict a first and second perspective view of another electrical connection apparatus  410  having a two pin configuration. Electrical connection apparatus  410  may otherwise be configured in a manner similar to that of electrical connection apparatus  10 ,  80 ,  100 , and  210 . 
         [0101]    In certain implementations, all or a portion of electrical connection apparatus  10 ,  80 ,  100 ,  210  and  410  may be over-molded in silicone or another polymer in order to reduce or eliminate the chance of moisture ingress. In addition, in certain implementations, pin  20  and pin  300  may have a variety of diameters and configurations. For example, pins coupled to leads that deliver electrical pulses may be larger than pins coupled to sensing leads. Accordingly, the pin receiving portions of apparatus  10 ,  80 ,  100 ,  210  and/or  410  may be configured to accept a pin having a desirable cross-section or configuration. 
         [0102]      FIG. 24  is a flowchart of a method ( 500 ) for electrically connecting an implanted medical device and an implanted stimulation electrode according to the present invention. According to  FIG. 24 , method ( 500 ) includes providing ( 510 ) a connection device having at least one stackable block and a first end block and a second end block arranged on a first and a second end of the at least one stackable block, where each of the at least one stackable block includes at least one pin receiving portion, and at least one electrical connection contact. Method ( 500 ) also includes inserting ( 520 ) a pin into at least one pin receiving portion such that the pin is electrically coupled to an implanted medical device or to an implanted stimulation electrode, and electrically coupling ( 530 ) to the lead portion the other of the implanted medical device or the implanted stimulation electrode. 
         [0103]    According to certain embodiments, the electrical connection apparatus passageway through which the proximal end of the lead must pass, with its exposed conductive surfaces in segments along its longitudinal axis, has a series of actively engageable seals or barriers alternating longitudinally with the conductive surfaces in the receptacle. When engaged, the active seals block the incursion of fluid along the lead&#39;s path, and prevent the migration of fluid from the region of one conductive surface in the receptacle to any other, and in the instance where there are already existing fluid bridges between conductors, forces the fluid out and breaks the electrical pathway. 
         [0104]      FIG. 25  is an isometric view of an active seal, according to certain embodiments. A single lead lumen is shown for clarity; but a plurality of lead lumens may also be provided in a single seal. The figure depicts a fluid seal  600  with a substantially planar body  601 . The perimeter  606  of the body  601  may be captured and compressed to form a boundary seal. The seal incorporates a cylindrical extension, or seal tube  602 , which has a lumen defining a pin receiving portion with diameter just large enough to permit passage of a lead  608  with little or no clearance. According to certain embodiments, the seal tube  602  is surrounded at one point by a metallic ring or cinch  603  that can be reduced in diameter in order to reduce the diameter of the seal tube  602  around the lead  608 . According to  FIG. 25 , the cinch  603  includes fixed position tabs  604  at one terminal end, which are captured by part of the housing of the connector block (see, e.g.,  FIG. 27A ). The other, opposite end of the cinch  603  comprises a moveable tab or tabs  605 , which is/are engaged by a moving a mechanism pushed by a cam (see, e.g.,  FIGS. 27A-27C ). Moveable tab  605  is forced towards and past fixed position tabs  604 , thus reducing the diameter of the cinch  603 . This compresses the material of the seal tube  602 , which then is pressed tightly to the outer surface of the lead  608 . Of course, both tabs may be movable towards and away from each other in order to constrict and relax the cinch  603 . 
         [0105]      FIG. 26  depicts a proximal end of an implanted lead  608 . The body of the lead comprises an insulating flexible polymer with internal conductors. At the proximal end, the conductors are exposed by means of external metal contacts such as rings  609 , with sections of insulator  610  between them to isolate them from each other. This proximal end of the implanted lead, commonly called a “pin” is the portion of the lead which enters the connector block. Dummy pins are also used which have the same diameter and proximal length as the lead pin. These dummy pins fit into the seal tubes  602  of  FIG. 25 , when the surgical scenario does not present with a sufficient number of lead pins to fill all the seal tubes on a device. 
         [0106]      FIG. 27A  is an isometric view of a two lumen  611  active seal incorporating a controlling mechanism, according to certain embodiments. The seal is composed of a base or body  601 , which includes two lead port seal tubes  602  with pin receiving portions formed of lumens  611  to accept passage of a lead  608 . A separate moving element of the structure is a rotating cam  612 . As the cam  612  is rotated, the ramp  613  on the surface of the cam  612  contacts and moves a slider  614 . Further rotation of the cam  612  will then force the slider  614  to rotate around its fixed anchor point  615  in the plastic block (not shown). The opposite end of the slider  614  contains a slot  616 , which entraps the moveable tab  605  of the seal&#39;s cinch  603  (See  FIG. 25 ). Moving the moveable tab  605  of the cinch  603  engages or activates the seal by compressing seal tube  602  outer diameter to a smaller dimension. In this state, the lead&#39;s conductive surfaces are isolated and the lead  608  is held in place by the increased frictional forces. The activated seal also fluidly isolates adjacent electrical connection contacts from each other. As a result, the lead conductive surface with its associated electrical connection contact together are fluidly isolated from other adjacent electrical connections and stackable blocks. 
         [0107]    According to  FIG. 27A , the cam  612  comprises a shaped opening  617  at its center. This opening  617  accommodates the central shaft (See, e.g.,  FIG. 28 ) having a shape complementary to the opening  617  so that when rotated, the shaft forces the cam  612  to rotate. Once the mechanism rotates the cam  612  to its fully engaged position, it will remain in that position. Reverse rotation of the cam  612  will relax the forces on the slider  614 , allowing the spring forces from the metallic cinch  603 , to expand the cinch  603  and release the seal. In this relaxed state, the lead  608  can move freely. 
         [0108]      FIG. 27B  is a magnified view of the active seal mechanism. The lead  608  can be seen inserted into one of the lumens  611  of the seal  601 . The cam  612 , in this instance, is not yet pressing against the slider  614 . However, the slider  614 , still grasps the moveable tab  605  of the cinch. The fixed position tabs  604  of the cinch are visible in their retained position. 
         [0109]      FIG. 27C  is a magnified view of the active seal mechanism with the cam  612  rotated to the latched position. Slider  614  is moved maximally to force the moveable tab  605  so that the cinch has its smallest diameter and tightly grasps the lead body  608 . Fixed position tab  604  remains fixed to its position, retained in place by in the block(not shown). 
         [0110]    According to certain embodiments, the cam  612  and/or the slider  614  may also be associated with a portion of an electrical connection contact such as tab  342 ,  362 . In this embodiment, a stackable block, e.g., block  220 , may include both the seal  600  as well as the electrical connection contacts  340 ,  360 . Rotation of a shaft associated with cam  612  and/or slider  614  may result in engagement of the seals and the electrical connection contacts. That is, the same controlling mechanism may be responsible for engaging both the seals and the electrical contacts. Accordingly, rotating cam  612  may rotate slider  614  causing each of the movable tab  605  and one or more of tabs  342 ,  362  provided on electrical connection contacts  340  and  360  to rotate into an activated position. In other embodiments, separate rotatable cams are associated with each of the electrical contacts and the seals, and each cam is responsible for causing its corresponding seal or electrical connection to move between the active and relaxed positions. For example, one stackable block  220  may be associated with an electrical connection contact  340 ,  360  and a cam  330  for controlling the diameter of the contact, while another stackable block  622  may be associated with a seal  600  and a cam  612 , and the stackable blocks  220 ,  622  may be operably coupled to one another. As a result, in an active seal state, the seal  600  fluidly isolates the electrical connection contact in the adjacent stackable block  220  from the stackable block  622  having the seal  600 . 
         [0111]      FIG. 28  is a cross-sectional view of a connector block assembly for an implantable device, according to certain embodiments. The examples of leads  608  show conductors as three rings  609  and an end pin  624  on each lead  608 . The lead  608  is shown inserted into the connector assembly which is comprised of a plurality of blocks  622 , which sandwich active seals, e.g., including seal tubes  602 , between the blocks. Along the body of the lead  608 , the seals partition the electrical contacts  621 , which connect to the lead&#39;s conductors  609 ,  624  into separate isolated sections. The centrally located activating shaft  625 , which powers the cam of  FIG. 27A , runs the full length of the assembly. 
         [0112]      FIG. 29  is a schematic of a cross section of a connector block  630  showing an alternative driving mechanism. The connector block  630  incorporates a seal  600  in one or more places. The cinch  603  with its attached moveable tab  605  surrounds the seal tube  602  as in previous figures. The connector block  630  body is penetrated by a threaded screw hole  631  that allows a screw  632  to travel from the outer edge of the connector  630  and impinge on the moveable tab  605 . Further travel of the screw  632  will then force the tab  605  to move. The moveable tab  605  movement will reduce the diameter of the cinch  603  and compress the seal tube  602  in a manner similar to that depicted in  FIGS. 27A and 27B . The screw serves as an alterative forcing structure to actuate the seal. Release of the seal tube&#39;s  602  compression is accomplished by reversing and removing the screw  632 . 
         [0113]    Additionally, according to certain embodiments, the active forces of the seal may isolate intentional fluids introduced in the body of the connector. Intentional fluids may include dielectric fluids such as mineral oil or mixtures containing mineral oil and may be included in, for example, pin receiving portions in order to provide lubricating properties, which may reduce the friction between the pin and inner surface of the seal tube and/or the electrical connection contact, thus reducing insertion forces. The intentional fluid may also serve as a hydrophobic fluid to oppose the intrusion of body fluids and other fluids, as an insulator by incorporating an intentional fluid with an appropriate dielectric coefficient, and/or as an isolator for isolating one contact from another. The intentional fluid may be a cleaning agent for dissolving organic debris such as blood. An antimicrobial chemical may be emulsified or dissolved into the fluid to prevent the growth of infectious entities such as bacteria or viruses on internal surfaces of the electrical connection apparatus or on the outer surface of the pin. 
         [0114]    While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
         [0115]    Although the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.