Abstract:
Tools for determining and adjusting the setting of an adjustable valve are disclosed. These tools allow a medical professional to locate and non-invasively determine the setting of an implanted valve. After the valve has been located and the setting of the valve determined, the valve may be re-adjusted non-invasively. There are three tools: a locator tool, an indicator tool and an adjustment tool. The locator tool allows the physician to locate the adjustable valve of interest and align the locator tool with a specific orientation of the valve. The indicator tool indicates the current setting of the adjustable valve and confirms new settings of the valve after the new settings have been implemented. The adjustment tool interacts magnetically with the implanted adjustable valve to couple with a movable internal element to change the setting of the valve. The indicator tool and the adjustment tool physically cooperate with the locator tool to accomplish the respective functions of the tools.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/148,151 filed on Jan. 6, 2014, which is a continuation of U.S. patent application Ser. No. 09/745,108 filed on Dec. 20, 2000, now U.S. Pat. No. 8,622,978 issued on Jan. 7, 2014, which is a continuation of U.S. patent application Ser. No. 09/270,540 filed on Mar. 17, 1999, now abandoned. The entire disclosures of the above applications are incorporated herein by reference. 
     
    
     FIELD 
       [0002]    The present disclosure relates to surgically implanted physiological shunt systems and related flow control devices. More particularly, the present invention relates to a position indicator and adjustment tool for such shunt systems having variable pressure settings for the one-way flow control valves controlling the flow of Cerebral Spinal Fluid (CSF) out of a brain ventricle and preventing backflow of fluid into the brain ventricle. 
       BACKGROUND 
       [0003]    This section provides background information related to the present disclosure which is not necessarily prior art. 
         [0004]    A typical adult has a total of about 120-150 cc of CSF with about 40 cc in ventricles in the brain. A typical adult also produces about 400-500 cc/day of CSF, all of which is reabsorbed into the blood stream on a continuous basis. 
         [0005]    Sometimes, the brain produces excess CSF. One common cause of the excess production of CSF is hydrocephalus. Hydrocephalus is a condition of excessive accumulation of CSF in the ventricles or brain tissue. Hydrocephalus can result from genetic conditions or from trauma to the brain. 
         [0006]    Excessive accumulation of CSF, due to hydrocephalus or other causes, manifests itself as increased pressure within the brain. Whatever the cause, over time, this increased CSF pressure causes damage to the brain tissue. It has been found that relieving the CSF pressure is therapeutically beneficial. This is usually done by draining CSF from the ventricles. 
         [0007]    Patients with hydrocephalus often continue to produce excess CSF, at least over some time period. Therefore, it is often desirable to continuously drain excess CSF to maintain normal CSF pressure in the brain. Excessive CSF accumulated in the ventricles of the brain is typically drained away from the brain using a shunt system. 
         [0008]    Where hydrocephalus is a chronic condition, the shunt system typically drains the CSF into the patient&#39;s peritoneal cavity or into the patient&#39;s vascular system. Such shunt systems typically have a catheter implanted in the ventricle of the brain. The catheter is connected to a fluid control device which is in turn connected to a catheter which empties in to the patient&#39;s peritoneal cavity or into the patient&#39;s vascular system. 
         [0009]    An example of a fluid control device is shown in U.S. Pat. No. 5,637,083 issued to William J. Bertrand and David A. Watson on Jun. 10, 1997 entitled “Implantable Adjustable Fluid Flow Control Valve”, the teaching of which is incorporated herein in its entirety by reference. The valve of the &#39;083 patent is shown in  FIGS. 1-3  generally labeled  10  ( 20 ). (Reference numbers in parentheses correspond to the reference numbers in the &#39;083 patent. After the corresponding reference number to the &#39;083 patent has been given once, no further reference to the &#39;083 will be given although the connection to the &#39;083 patent is intended to be implied throughout this description.) The valve  10  includes a an inlet connector  12  ( 22 ) and an outlet connector  14  ( 24 ). A elastomeric casing  16  ( 30 ) covers the inner workings of the valve  10 . A dome  18  ( 60 ) extends upward from the elastomeric casing  16 . Fluid flows through the valve  10  in the direction indicated by the arrow “A”. 
         [0010]    Valve  10  includes a mechanism to control fluid flow through the valve  10 . The mechanism includes a magnet  20  ( 120 ) embedded within a base  22  ( 122 ). Rotating the base  22  changes the internal configuration of the mechanism. Changing the internal configuration of the mechanism produces a variety of pressure or flow characteristics for the valve. The base  22  may be rotated by magnetically coupling an external magnet  24  ( 140 ) to the valve&#39;s magnet  20  and rotating the external magnet  24 . Because magnet  20  is coupled to the external magnet  24 , when magnet  24  rotates, magnet  20  also rotates. As magnet  20  rotates, base  22  rotates and the internal configuration of the mechanism changes as described in detail in the &#39;083 patent. As the internal configuration of the valve  10  changes, the pressure/flow characteristics of the valve  10  change. In use, the valve  10  is subcutaneously placed on the patient&#39;s skull. The catheter going to the patient&#39;s ventricle in attached to inlet connector  12 . The catheter going to the patient&#39;s peritoneal cavity or vascular system is attached to outlet connector  14 . In this way, a direction of flow is established from the inlet connector  12  through the valve  10  to the outlet connector  14 . As stated above and described in detail in the &#39;083 patent, changing the internal configuration of the mechanism by coupling the external magnet to the internal magnet and rotating the base produces a variety of pressure or flow characteristics through the valve  10 . 
         [0011]    A problem with current adjustable valves, such as the one described in the &#39;083 patent is that once implanted, it is difficult to determine the setting of the valve. Further, it is difficult to adjust the setting of the valve. With some adjustable valves, x-ray images are used to determine the current state or post adjustment state of the valve. 
       SUMMARY 
       [0012]    This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
         [0013]    Tools for determining and adjusting the setting of an adjustable valve are disclosed. These tools allow a medical professional to locate and non-invasively determine the setting of an implanted valve. After the valve has been located and the setting of the valve determined, the valve may be re-adjusted non-invasively. 
         [0014]    There are three tools: a locator tool, an indicator tool and an adjustment tool. The locator tool allows the physician to locate the adjustable valve of interest and align the locator tool with a specific orientation of the valve. The indicator tool indicates the current setting of the adjustable valve and confirms new settings of the valve after the new settings have been implemented. The adjustment tool interacts magnetically with the implanted adjustable valve to couple with a movable internal element to change the setting of the valve. The indicator tool and the adjustment tool physically cooperate with the locator tool to accomplish the respective functions of the tools. 
         [0015]    In this invention a hand held indicator tool allows instant determination of the device setting with no requirement for using x-rays. This is accomplished in the present invention by providing a locator tool with an opening that allows tactile determination of the implanted valve&#39;s position and orientation. In the preferred embodiment, the indicator tool in this invention is keyed to the locator tool so that it can only be inserted in a correct orientation with respect to the locator tool that has previously been aligned with the valve. The “keyed” relationship minimizes the possibility of erroneous readings of the valve setting. 
         [0016]    In the current invention, the adjuster tool is inserted into the locator tool. The adjustment tool couples an external magnetic field to the magnet of the valve to switch the valve through a variety of pressure/flow characteristics. The adjuster tool rotates through a series of “detents” corresponding with setting positions on the valve. As the adjuster tool rotates, the user feels a click when the adjuster tool is aligned with a position of the valve as a positive tactile indication the user that a setting position has been reached. In the current invention, mechanical stops in the tool mirror mechanical stops inside the implanted valve at the range limit of rotating base of the valve. This helps prevent the user from improperly adjusting the valve. 
         [0017]    Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0018]    The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
           [0019]      FIG. 1  is a perspective view of an adjustable flow control valve. 
           [0020]      FIG. 2  is a side cross-sectional view of the valve of  FIG. 1 . 
           [0021]      FIGS. 3A-3E  are top x-ray views of the valve of  FIG. 1  with the magnet in a variety of orientations corresponding to varying levels of pressure/flow through the valve. 
           [0022]      FIG. 4  is a perspective view of the locator tool of the present invention. 
           [0023]      FIG. 4 a    is a perspective view of an alternate embodiment of the locator tool of the present invention. 
           [0024]      FIG. 5  is a top view of the locator tool of  FIG. 4 . 
           [0025]      FIG. 6  is a side cross-sectional view of the locator tool of  FIG. 4 . 
           [0026]      FIG. 7  is a bottom view of the locator tool of  FIG. 4 . 
           [0027]      FIG. 8  is a perspective view of the indicator tool of the present invention. 
           [0028]      FIG. 9  is a top view of the indicator tool of  FIG. 8 . 
           [0029]      FIG. 10  is a side cross-sectional view of the indicator tool of  FIG. 8 . 
           [0030]      FIG. 11  is a side view of the indicator tool of  FIG. 8 . 
           [0031]      FIG. 12  is a top view of the compass of the indicator tool of  FIG. 8 . 
           [0032]      FIG. 13  is a side view of the compass of  FIG. 12 . 
           [0033]      FIG. 14  is a perspective view of the adjustment tool of the present invention. 
           [0034]      FIG. 15  is a top view of the adjustment tool of  FIG. 14 . 
           [0035]      FIG. 16  is a bottom view of the adjustment tool of  FIG. 14 . 
           [0036]      FIG. 17  is a side cross-sectional view of the adjustment tool of  FIG. 14  without the magnet in place. 
           [0037]      FIG. 18  is a side cross-sectional view of the adjustment tool of  FIG. 14  with the magnet in place. 
           [0038]      FIG. 19  is a top view of the locator tool of  FIG. 4  in position on an adjustable valve. 
           [0039]      FIG. 20  is a top view of the indicator tool of  FIG. 8  in place in the locator tool of  FIG. 19 . 
           [0040]      FIG. 21  is a perspective view of the adjustment tool of  FIG. 14  being moved into contact with the locator tool of  FIG. 19 . 
           [0041]      FIG. 22  is a top view of the adjustment tool of  FIG. 21  in place in the locator tool of  FIG. 19 . 
       
    
    
       [0042]    Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
       DETAILED DESCRIPTION 
       [0043]    Example embodiments will now be described more fully with reference to the accompanying drawings. 
         [0044]    The invention comprises three tools, a locator tool  26 , an indicator tool  28  and an adjustment tool  30 . Although these tools are intended to be used cooperatively in a sequential way, it is clear and within the scope of the invention that they may also be used individually are in paired relationships as will be explained hereafter. 
         [0045]    The locator tool is shown in  FIGS. 4-7  generally labeled  26 . Locator tool  26  allows the physician to locate the adjustable valve  10  of interest and align the locator tool  26  with a specific orientation of the valve  10 . 
         [0046]    Locator tool  26  has a substantially planar deck  32  and a substantially cylindrical tube  34 . The outer edge  36  of deck  32  is attached to the inner surface  38  of tube  34 . Tube  34  has in inner diameter “D”. Tube  34  has an upper surface  40 . Deck  32  has a locator central axis  42 . Deck  32  has a locator central opening  44  extending entirely therethrough. In the preferred embodiment, locator central axis  42  extends through a portion of locator central opening  44 . In addition, locator central opening  44  has a shape as will be described below such that it allows an orientation to be ascribed to it. Deck  32  also has an arrow  46  or other means for pointing out the preferred direction of orientation of the locator tool  26 . 
         [0047]    Tube  34  preferably has a slot  48  on its inner surface  38  that extends into the material of tube  34  from the upper surface  40  downward at substantially a right angle to the plane of deck  32 . Slot  48  is intended to interact with the indicator tool  28  as will be described hereafter. 
         [0048]    In the preferred embodiment, as seen in  FIG. 6 , tube  34  has a tab  50  that extends as part of “wall” of tube  34 . Tab  50  is formed between two side slots  52  and a bottom slot  54  that extend entirely through the material of tube  34 . Tab  50  preferably extends along tube  34  in a direction substantially perpendicular to the plane of deck  32 . 
         [0049]    A protrusion  56  extends inwardly from the bottom of tab  50  into the central portion of tube  34 . Because tab  50  is attached to the main body of tube  34  only at its upper dimension, tab  50  is biased to remain positioned within the dimensions of the “wall” of tube  34 . If protrusion  56  is pushed outwardly, for example with contact with the adjustment tool  30  as will be explained hereafter, tab  50  is biased to resist such displacement and to tend to move itself and protrusion  56  back to their original unstressed position. 
         [0050]    In an alternate embodiment shown in  FIG. 4 a   , the upper surface  40  of tube  34  has a series of indentations  58  located at certain locations around the upper surface  40 . The purpose of these indentations  58  will be explained in more detail hereafter. 
         [0051]    An index  59  may be placed on the upper surface  40  of tube  34 . Index  59  visually indicates the settings of valve  10  when locator tool  26  is correctly oriented with valve  10 . 
         [0052]    In many adjustable valves, such as the valve  10  shown in U.S. Pat. No. 5,637,083, the dome  18  of the valve  10  has a direction of orientation. For example, in the valve  10  shown in the &#39;083 patent, the width “W” of the dome  18  is narrower transverse to the direction of fluid flow “A” than is the length “L” of the dome  18  along the direction of fluid flow “A” as shown in  FIGS. 1-3 . This difference in dimensions allows the dome  18  itself to have a direction of orientation. In this case, the elongated dimension of the dome  18  is aligned with the direction of fluid flow “A” through the valve  10 . 
         [0053]    In use, the valve  10  is implanted under the patient&#39;s skin on the skull. The skin around the skull is relatively thin. Thus, the physician can palpate the valve  10  through the skin. By feeling the dome  18  and other physical characteristics of the valve  10 , the physician can identify the orientation of the dome  18 . 
         [0054]    Locator central opening  44  is slightly larger than and essentially the same shape as the dome  18  on the adjustable valve  10 . As a result, locator central opening  44  also has a direction of orientation that will correspond to the orientation of the dome  18 . Once the physician has palpated the dome  18  of the implanted valve  10  and determined its orientation, he sets the locator tool  26  over the dome  18 . The dome  18  will extend into the locator central opening  44 . Because the dome  18  and the locator central opening  44  have similar shape, by rotating the deck  32  about the locator central axis  42 , the physician will eventually bring the dome  18  and the locator central opening  44  into alignment. This will occur where the clearance between the locator central opening  44  and the dome  18  is minimized. When this alignment occurs, the locator tool  26  will be aligned with the valve  10  ( FIG. 19 ). In this position, the arrow  46  will point in the direction of fluid flow through the valve  10 . 
         [0055]    As described, in the preferred embodiment, the locator central opening  44  has a similar shape to the dome  18 . In particular, the locator central opening  44  has an elongated shape that corresponds to the shape of the dome  18 . Although this is the preferred shape of locator central opening  44 , other shapes may also be used. For example, if dome  18  has a different shape, cylindrical, circular, spherical, slot-shaped, diamond, triangular, rectangular or irregular, to name but a few of the many possible choices that will occur to those skilled in the art, locator central opening  44  would also have a corresponding shape. The key here is to have a shape for the locator central opening  44  that allows the locator tool  26  to be oriented to and aligned with the valve  10  in a precise predictable manner. Additionally, in the preferred embodiment, locator central opening  44  should allow the physician to palpate the implanted valve  10  through the locator central opening  44 . 
         [0056]    The indicator tool is shown in  FIGS. 8-13  generally labeled  28 . The indicator tool  28  indicates the current setting of the adjustable valve  10  and confirms new settings of the valve  10  after the new settings have been implemented. 
         [0057]    Indicator tool  28  has two main parts: an indicator central body  60  and a compass  62 . Indicator central indicator central body  60  has an annular portion  64 . Annular portion  64 , in the preferred embodiment, is cylindrical with an outer diameter “E” that is slightly less than the inner diameter “D” of tube  34 . An indicator lip  66  extends outward from the upper surface  68  of indicator central body  60 . The outer diameter “T” of indicator lip  66  is larger than the inner diameter “D” of tube  34 . 
         [0058]    In the preferred embodiment corresponding to the embodiment of the locator tool  26  having a slot  48  on the inner surface  38  of tube  34 , central body  60  has a ridge  70  extending outward from its outer surface  72 . Ridge  70  extends upward from the bottom  74  of the central body  60  at substantially a right angle to indicator lip  66 . Ridge  70  is dimensioned to slide into slot  48  so that the interaction between slot  48  and ridge  70  will keep central body  60  from rotating with respect to the locator tool  26  in use as will be described hereafter. 
         [0059]    In an embodiment corresponding to the embodiment of the locator tool  26  having indentations  58  described above, protrusions  76  extend downward from the underside  78  of lip  56 . These protrusions  76  are positioned to correspond to the indentations  58  on the upper surface  40  of tube  34 . In this way, when indicator tool  28  is used with locator tool  26  and the protrusions  76  are aligned with the indentations  58 , indicator tool  28  is precisely oriented with locator tool  26  and central body  60  is inhibited from rotating with respect to locator tool  26  as will be described hereafter. 
         [0060]    Indicator central body  60  has a indicator central opening  80  extending around an indicator central axis  82 . A compass  62  is fixed in place in indicator central opening  80 . Compass  62  has a magnetized pointer  84  that rotates around a spindle  86  so that pointer  84  may align itself with magnetic fields it encounters. 
         [0061]    Although the preferred embodiment has compass  62  fixed in central opening  80 , in another embodiment, indicator central body  60  has no central opening. In this embodiment, compass  62  may be attached directly to indicator central body  60  by means such as adhesives as will be clear to those skilled in the art. 
         [0062]    An index  88  is affixed to the upper surface  68  of indicator central body  60  around compass  62 . Index  88  indicates the possible positions of the mechanism of the adjustable valve  10  corresponding to the different settings of the valve  10 . 
         [0063]    In use, after the orientation of the valve  10  has been established by locator tool  26  as described above, the indicator central body  60  of indicator tool  28  is placed within tube  34  of locator tool  26 . Because the outer diameter “E” of the annular portion  64  of the indicator central body  60  is slightly smaller than and is conformal to the inner diameter of tube  34 , indicator central body  60  should pass into tube  34  until lip  56  contacts and rests upon the upper surface  40  of tube  34 . 
         [0064]    In the preferred embodiment, ridge  70  will align with and interact with slot  48  to precisely orient indicator tool  28  with locator tool  26 . In the alternate embodiment, indicator lip  66  is rotated until protrusions  76  are in contact with the indentations  58  in locator tool  26 . In either configuration, locator tool  26  and indicator tool  28  are aligned and oriented with respect to the preferred orientation of valve  10  ( FIG. 20 ). Pointer  84  will then interact with the magnet  20  of valve  10  so that pointer  84  will align itself with the magnet  20  of valve  10 . This will cause pointer  84  to point to a spot on index  88 . Where the pointer  84  points to on index  88  indicates the position of the magnet  20  of the valve  10 . The position of the magnet  20  indicates the setting of the valve  10 . 
         [0065]    The adjustment tool is shown in  FIGS. 14-18  generally labeled  30 . The adjustment tool  30  interacts magnetically with the implanted adjustable valve  10  to couple with the magnet  20  fixed to a movable internal element in valve  10  to change the setting of the valve  10 . 
         [0066]    Adjustment tool  30  has two main parts: an adjustment central body  90  and a magnet  92 . Magnet  92  performs the function of the external magnet  24  described above. Adjustment central body  90  has an adjustment annular portion  94  made up of an outer wall  96 , an inner wall  98  and an upper wall  100 . Adjustment annular portion  94  has an annular open area  102  between outer wall  96  and inner wall  98  and opposite upper wall  100 . In the preferred embodiment, outer wall  96  is cylindrical with an outer diameter “G” that is slightly less than the inner diameter “D” of tube  34 . An adjustment lip  104  extends outward from the upper edge  106  of adjustment central body  90 . The outer diameter “H” of adjustment lip  104  is larger than the inner diameter “D” of tube  34 . In the preferred embodiment, adjustment lip  104  is made of a clear material so that index  59  may be viewed through adjustment lip  104  when adjustment tool  30  is in place on locator tool  26 . 
         [0067]    Adjustment central body  90  has a series of indentations  108  near its bottom  110 . These indentations  108  are located a distance from adjustment lip  104  and configured so that the indentations  108  will interact with protrusion  56  on tab  50  when adjustment tool  30  is mated to locator tool  26  as described below. Indentations  108  are spaced around the periphery of adjustment central body  90  corresponding to the location of the settings of the valve  10 . 
         [0068]    Magnet  92  is fixed in place in within adjustment central body  90 . Magnet  92  has a north pole N and a south pole S aligned along an axis “J” of adjustment central body  90 . Axis J is aligned with a direction indicator which is preferentially in the form of an arrow  112 . 
         [0069]    In use, the orientation of the valve  10  is first established by locator tool  26  and indicator tool  28  as described above. Then, the adjustment tool  30  is used, as necessary or as desired, to change the position of the magnet  20  and consequently the setting of the valve  10 . This is done by first removing indicator tool  28  from locator tool  26 . Then, adjustment tool  30  is positioned above locator tool  26  with the arrow  112  aligned with the pressure level setting on index  59  determined by the indicator tool  28  ( FIG. 21 ). Maintaining this alignment, the adjustment tool  30  is lowered toward the locator tool  26  until the adjustment central body  90  enters tube  34  and adjustment lip  104  contacts the upper surface  26  of tube  34 . At this time, protrusion  56  should interact with one of the indentations  108  on adjustment central body  90  that corresponds to the current setting of the valve  10  ( FIG. 22 ). 
         [0070]    In this position, magnet  92  couples with magnet  20  in valve  10 . Adjustment central body  90  is then rotated so that the arrow  112  points to the desired setting of valve  10  indicated on index  59 . Because magnet  20  is magnetically coupled to magnet  92 , as magnet  92  rotates with adjustment central body  90 , magnet  20  will also rotate and thereby move to the desired setting of valve  10 . As central body  90  rotates, protrusion  56  will be moved out of contact with the indentation  108  corresponding to the last setting of the valve and move against the outer surface outer wall  96  of central body  90 . When magnet  92  has moved to the next setting of the valve  10 , protrusion  56  should contact the next indentation  108  corresponding to the next setting of the valve  10 . The user should feel the protrusion  56  moving into or out of this indentation  108 . In this way, the user has tactile confirmation that the adjustment tool  30  has moved to and is aligned with a new valve setting. This process may be repeated as desired until the adjustment tool  30  has moved the magnet  92 , and correspondingly the magnet  20 , to the new ultimate valve setting. 
         [0071]    After the magnet  20  of valve  10  has been moved to a new setting, indicator tool  28  should be used again as described above to confirm that magnet  20  is in the desired position and that, therefore, valve  10  is at the desired valve setting. 
         [0072]    In the described preferred embodiment, locator tool  26  is mechanically coupled to either indicator tool  28  or adjustment tool  30  through the interaction of tube  34  and either indicator central body  60  or adjustment central body  90 , respectively. In this embodiment, the hollow cylinder formed by tube  34  “captures” the cylindrical bodies of indicator central body  60  or adjustment central body  90  within the central portion of tube  34 . Although this is the preferred embodiment, it is clear that locator tool  26  may be mechanically coupled to either indicator central indicator central body  60  or adjustment central body  90  by other means. For example, a cylindrical tube  34  could be “captured” within a downward extending cylinder from indicator tool  28  or adjustment tool  30 . In this embodiment, there may also be slots  48  and ridges  70  or other alignment means to orient and align the indicator tool  28  with the locator tool  26 . 
         [0073]    Alternately, with respect to the interaction between the locator tool  26  and the indicator tool  28 , instead to the inner surface  38  of tube  34  and indicator central body  60  both being conformally cylindrical, the inner surface  38  and indicator central body  60  may have other conformal shapes that allow the two tools to be mated together and maintain a desired orientation. For example, the inner surface  38  of tube  34  may be square, rectangular, hexagonal, elliptic or any other shape. Indicator central body  60  would also have a corresponding conformal shape. In this way, when indicator tool  28  is mated with locator tool  26 , indicator tool  28  would be precisely located and oriented with respect to locator tool  26 . Other means may occur to those skilled in the art. 
         [0074]    All such means for mechanically coupling the locator tool  26  to either indicator central indicator central body  60  or adjustment central body  90  are intended to be within the scope of the invention. The key function of such mechanical coupling means is to ensure that the indicator central indicator central body  60  or adjustment central body  90  are aligned with the locator tool  26 . Further, whatever the design, it is a key function of the mechanical coupling means to ensure that the magnet  92  of the adjustment central body  90  is allowed to be magnetically coupled to and rotate the magnet  20  of the valve  10  in a controllable fashion. 
         [0075]    Further, the interaction of slot  48  or protrusions  76  on tube  34  with ridge  70  or indentations  58  of indicator tool  28 , respectively, helps to align the indicator tool  28  with the locator tool  26 . Although this is the preferred method of aligning these tools, other ways of aligning the tools will occur to those skilled in the art in addition to the means for mechanically coupling locator tool  26  to indicator tool  28  described above, which provides an alignment of the locator tool  26  and indicator tool  28 . These additional means include, but are not limited to, reversing the placement of the slots and ridges or protrusions and detents on the respective tools. In addition, other means of mechanical alignment will occur to those skilled in the art. 
         [0076]    Further, another aid in aligning the locator tool  26  and the indicator tool  28  include visual indicators of position on the respective devices. Examples of these visual means to aid in aligning the respective tools include, but are not limited to aligning indicator marks, line, templates or the like on the respective devices. 
         [0077]    In addition, locator tool  26  has been described in the preferred embodiment having a locator central opening  44  to allow the physician to palpate the valve  10  through the locator central opening  44 . Although this is the preferred embodiment, locator tool  26  may also not have a locator central opening  44 . In this embodiment, the physician would align the locator tool  26  with the valve  10  by other means. One such means could be determining the orientation of the valve  10  by palpating the valve  10  and then noting the direction of orientation on the patient&#39;s skin by a marking on the patient&#39;s skin. Locator tool  26  would then be aligned with the marking on the patient&#39;s skin. 
         [0078]    In this description, the use of the tools has been described as being cooperative and substantially sequential. So for example, the locator tool  26  is used first to establish an orientation aligned with the valve  10 . Thereafter, the indicator tool  28  is used to indicated the current setting of the valve  10 . Then, the adjustment tool  30  is used, if needed, to move the valve  10  to a new setting. Finally, the indicator tool  28  is used again to confirm that the new setting is in fact the desired setting. 
         [0079]    It is within the scope of the invention to use the locator tool  26  and the indicator tool  28  without ever using adjustment tool  30 . In this embodiment of the invention, the information on the current setting of the valve  10  may be sufficient or may be used with some other means to change the setting of the valve  10 . 
         [0080]    It is also within the scope of the invention to use the locator tool  26  and the adjustment tool  30  without using the indicator tool  28 . In this embodiment of the invention, the setting of the valve  10  would be determined by other means, such as by x-ray, or inferred. In any case, the setting of the valve  10  would be determined without using the indicator tool  28 . Thereafter, the adjustment tool  30  would operate as described above to change the setting of the valve  10 . 
         [0081]    The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.