Abstract:
A locator device precisely identifies a predetermined spot which is hidden by a skin. The device is an outer washer and an inner washer with both washers being magnetized. The inner washer is positioned underneath the skin to mark the location of the predetermined spot therein. The outer washer aligns with the inner washer when proximate thereto to thereby locate said predetermined spot.

Description:
TECHNICAL FIELD 
   This invention relates generally to the field of spot locator devices, and, more particularly, to a device for locating a specific spot or spots through the skin. 
   BACKGROUND OF THE INVENTION 
   Often time, it is desired to locate a specific spot under the human skin which is covered by said skin. For example, often in the medical profession drug releasing devices are placed underneath a patient&#39;s skin. These devices release medicine at a predetermined rate thereby maintaining a constant level of medicine in the patient&#39;s body without the need for frequent injections or infusions of food. However, periodically the medicines within the drug releasing devices must be replenished which requires the use of a syringe puncturing the skin and injecting the medicine into the drug releasing device. However, because the device is buried beneath the skin, often the wielder of the syringe has a difficult time locating the precise spot to puncture. 
   Thus, there is a need for a device to precisely locate a spot hidden beneath a surface. 
   Inamed Corporation has developed a tissue expanding system for cosmetic surgery in which employs a high gauss level magnet that is mounted on a gimbal outside a patient&#39;s skin. The device is used to detect another high gauss magnet located at the bottom of a dispensing chamber implanted under the skin. The implanted magnet may cause a disruption in the operation of nearby electronic or electrically operated medical devices. In addition, due to its size and complexity, this gimbal mounted magnet is expensive. Further, this device must be sterilized prior to each use. 
   To use, the gimbal mounted magnet is moved in about above the skin approximately where the implanted magnet is located. This scanning is a necessary part of the process since all implanted devices shift position underneath the skin. Thus, the exact location must be determined before each injection. 
   When the implanted magnet is detected, a mark is made with a medical marking pen on the skin. The procedure is repeated several times thereby resulting in a plurality of marks on the skin in a group. A syringe is injected into the center of the grouped markings through the skin and into the dispensing chamber. Resistance to the syringe&#39;s movement is detected when contact is made with the implanted magnet at the bottom of the dispensing chamber. The contact may, in some instances, cause damage to the needle. 
   The Inamed Corporation&#39;s method and apparatus provides an approximate insertion point but does have a margin of error and is time consuming. 
   Thus, none of the known prior art disclose the combination set forth herein. 
   SUMMARY OF THE INVENTION 
   It is an object of this invention to provide a device for precisely locating a spot hidden beneath a skin surface. 
   Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming a part of this specification. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention may be more readily described by reference to the accompanying drawings in which: 
       FIG. 1  is a perspective partial cut away view of one embodiment of the present invention; 
       FIGS. 2 and 2A  are top and side views of a magnetic disc comprising the outer component of the present invention; 
       FIGS. 3 and 3A  are top and side views of another magnetic disc comprising the inner component of the present invention; 
       FIG. 4  is a cross sectional side view of the embodiment of  FIG. 1  in use with a sheet; 
       FIG. 5  is a perspective view of an alternate embodiment of the present invention; 
       FIG. 6  is a perspective view of an alternate method of aligning the present invention; 
       FIG. 7  is a cross sectional side view of an alternate embodiment of the present invention used with a shell; 
       FIG. 8  is a cross sectional side view of an alternate embodiment of the present invention used with a tissue expander; 
       FIG. 9  is a partial cross sectional side view of an alternate embodiment of the present invention; 
       FIG. 10  is side view of one embodiment of a needle useful in the present invention; 
       FIG. 11  is a side view of another embodiment of a needle useful in the present invention; 
       FIG. 12  is a cross sectional side view of an alternate multiport locator embodiment of the present invention; 
       FIG. 13  is a top view of a magnetic disc comprising the outer component of the embodiment of  FIG. 12 ; and 
       FIG. 14  is a top view of another magnetic disc comprising the inner component of the embodiment of  FIG. 12 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring more particularly to the drawings by characters of reference,  FIGS. 1-4  disclose combinations of features which constitute the components of a locator device  10  of the present invention. In the illustrated embodiment, locator device  10  comprises an outer washer  12  and an equal sized inner washer  14 . Washers  12  and  14  are magnetic as described further below. 
   To practice the invention, the user first determines a precise spot  30  to be located under a patient&#39;s skin  18 . Skin  18  is opened and inner washer  14  is positioned on spot  30  with its center marking the location of same. Skin  18  is then re-positioned over inner washer  14  with an axis  28  of said washer  14  oriented perpendicular to skin  18 . Skin  18  will heal naturally over inner washer  14 . 
   For exemplary purposes, spot  30  is the location of a drug dispensing device. Note that these are for exemplary purposes and that the invention is not limited to such uses. Those skilled in the art will recognize that the invention is useful in locating a precise spot through the skin surface and has many other uses than those described herein. For example, the invention&#39;s use in connection with a tissue expander is discussed below. Another use is to precisely locate feeding tubes for those patient&#39;s needing same. In the prior art, feeding tubes often cause infection around the site where said tubes enter the skin. The present invention allows the placement of such feeding tubes underneath the skin thereby lessening this chance of infection. 
   Each washer  14  and  12  is magnetized whereby one flat surface is a north magnetic pole  24  while the other flat surface is a south magnetic pole  26 . Washers  12  and  14  are positioned whereby those surfaces of said washers abutting skin  18  are of opposing poles. In the illustrated example, the surface of inner washer  14  abutting skin  18  is north pole  24  and the surface of outer washer  12  abutting skin  18  is south pole  26 . Those skilled in the art will recognize that having the surface of inner washer  14  abutting skin  18  as south pole  26  and the surface of outer washer  12  abutting skin  18  north pole  24  will not change the functionality of said devices. The key is that the surfaces of washers  12  and  14  abutting skin  18  must be opposing poles. 
   Additionally, the invention is best operated when inner washer  14  is positioned abutting skin  18  and not buried deep within the body. By doing so, the magnetic forces needed to operate device  10  are minimized. The minimization greatly reduces the possibility of disrupting nearby devices which may be implanted in the body or positioned nearby. 
   Center holes  13  and  15  extend through the centers of outer washer  12  and inner washer  14 , respectively. In the preferred embodiment best seen in  FIGS. 2 ,  2   a ,  3  and  3   a , center hole  15  of inner washer  14  is a larger diameter than center hole  13  of outer washer  12  and includes a tapered sidewall  16 . 
   In the preferred embodiments of  FIGS. 1-4 , a layer  17  of a self sealing material is mounted on the surface of inner washer  14  which is opposite skin  18 . If preferred, said self-sealing material extends into center hole  15  as shown in  FIG. 8 . 
   To position the outer washer  12  in one method best seen in  FIG. 4 , a sheet  32  of a slick material such as Teflon® is placed over skin  18 . Sheet  32  includes a hole  33  which is preferably larger than either holes  13  and  15 . Outer washer  12  is brought proximate to sheet  32  with, in this example, south pole  26  abutting sheet  32 . The magnetic attractive forces from the north pole  24  of inner washer  14  and south pole  26  of outer washer  12  forces washers  12  and  14  into alignment along axis  28  which thereby aligns center holes  13  and  15 . Sheet  32  allows easier sliding movement of washers  12  and  14  into alignment. Once washers  12  and  14  are aligned, sheet  32  can be slid about skin  18  to align hole  33  thereof with holes  13  and  15 . Those skilled in the art will recognize other methods of accomplishing same are possible, including, but not limited to, use of lubricating agents such as lotions, jellies or oils applied to skin  18 . 
   In another variation seen in  FIG. 5 , a finger loop  50  is mounted at one end of a string member  52 . The other end of string member  52  is affixed to outer washer  12 . In use, the user suspends washer  12  over the proximate location of inner washer  14  using finger loop  50 . Once the outer washer  12  is magnetically attracted to inner washer  14 , finger loop  50  and string member  52  are used to slowly lower outer washer  12  into contact with skin  18 . Since friction is virtually non-existent, magnetic forces align holes  13  and  15  without the need to slide outer washer  12  over skin  18  thereby obviating the need for a sheet  32  or lubricating agents. 
   In another variation seen in  FIG. 6 , a tweezer device  60  having two juxtaposed arms  62  with inwardly extending grips  64  is employed to grasp outer washer  12 . As in the prior discussion regarding the embodiment of  FIG. 5 , the user suspends washer  12  over the proximate location of inner washer  14  using tweezer device  60 . Once the outer washer  12  is magnetically attracted to inner washer  14 , tweezer device  60  is used to slowly lower outer washer  12  into contact with skin  18 . Since friction is virtually non-existent, magnetic forces align holes  13  and  15  without the need to slide outer washer  12  over skin  18  thereby again obviating the need for a sheet  32  or lubricating agents. 
   The alignment of holes  13  and  15  marks precisely spot  30  for the user outside skin  18 . Once aligned, needles or syringes  19  are employed by inserting same through holes  13  and  15 . 
   The key to the present invention is the use of magnetic fields to align an inner magnet with an outer magnet. This alignment is accomplished without the need to refer to x-y coordinates and the like for placement. The present examples using washers  12  and  14  are illustrative and are not meant to limit the invention to the use of discs only. 
   Those skilled in the art will recognize one advantage to the use of washers  12  and  14  is that such devices are very inexpensive and easy to manufacture. Because of the inexpensive nature of said washers  12  and  24 , outer washer can simply be disposed of after each use thereby avoiding the need for expensive, time consuming re-sterilization. 
   In the alternate embodiment of  FIG. 7 , a dispensing chamber  40  having one or more exit holes  42  is mounted to the surface of inner washer  14  opposite skin  18 . Exit holes  42  allow the contents of dispensing chamber  40  to seep into the surrounding matter at a controlled rate, as, for example, to dispense medicine to a patient. 
   To refill dispensing chamber  40  as needed, outer washer  12  is used as in one of the methods previously described. Syringe needle  19  is then inserted from the outside of skin  18  through center holes  13  and  15  and self sealing material  17  and hence into dispensing chamber  40 . In this variation, self-sealing material  17  includes an extension  41  into center hole  15 . A thickened silicone or a ceramic coating  46  is provided to that portion of dispensing chamber  40  which is aligned with and positioned opposite center holes  13  and  15 . Coating  46  prevents needle  19  from puncturing dispensing chamber  40 . In addition, the added resistance felt when syringe  19  encounters coating  46  tells the user when needle  19  is properly positioned. Once needle  19  is positioned, medicine can be injected to fill or refill dispensing chamber  40 . 
   In the alternate embodiment of  FIG. 8 , the present invention is used in connection with a tissue expander  82 . As described previously in connection with  FIG. 7 , dispensing chamber  40  having exit holes  42  is mounted to the surface of inner washer  14  opposite skin  18 . However, instead of allowing the contents of dispensing chamber  40  to seep into surrounding tissue, in this embodiment, exit holes  42  allow the contents of dispensing chamber  40  to seep into a bladder  80  at a controlled rate thereby expanding bladder  80 , and the surrounding tissue, as desired. 
   To refill dispensing chamber  40  as needed, outer washer  12  is used as in one of the methods previously described. Syringe needle  19  is then inserted from the outside of skin  18  through center holes  13  and  15  and self sealing material  17  and hence into dispensing chamber  40 . In this variation, self-sealing material  17  includes an extension  41  into center hole  15 . A thickened silicone or a ceramic coating  46  is provided to dispensing chamber  40  which is aligned with center holes  13  and  15  from needle  19  from puncturing dispensing chamber  40 . In addition, the added resistance felt when syringe  19  encounters coating  46  tells the user when needle  19  is properly positioned. Once needle  19  is positioned, a solution can be injected to fill or refill dispensing chamber  40 , and hence bladder  80 , until a predetermined amount has been injected. 
   Still another variation seen in  FIG. 9  provides a dispensing chamber  90  positioned as described previously for  FIG. 7  but having a coil  92  extending therefrom deeper into the tissues  37  and  39  underneath skin  18 . At the end of coil  92 , a release mechanism  94  allows medicine to seep into the deeper tissues as desired. This variant allows for dispensing of medicine into deeper tissues while still allowing use of surface magnets with the advantages previously discussed. 
   In addition, use of the variation of  FIG. 9  eliminates or significantly reduces the dangers of nerve damage which can be caused by injection needles as needle or syringe  19  is always injected into a known protected area. Use of coil  92  permits medicines to reach deep within the tissues even though a relatively short needle or syringe  19  is employed. Further, in somewhat of a reverse use, needle or syringe  19  can be used in conjunction with coil  92  and chamber  90  to remove or drain areas deep within the body, for example, after surgery. 
   While the usual needle  19  configuration is operable with the present invention, two variations of needle  19  construction are shown in  FIGS. 10 and 11 . In  FIG. 11 , the distal end of needle  19  includes a larger opening  110  to facilitate movement of liquid  112  therethrough. In  FIG. 10 , the distal end  100  of needle  19  is solid with an opening  102  positioned above said solid distal end whereby liquid  112  flows from needle  19  without potential obstruction from coating  46 . 
   For those patients who require multiple injection points, a multiport locator device  120  is shown in  FIGS. 12-14 . Multiport locator device  120  includes an outer disc  122  and an inner disc  124 . Each disc  122 ,  124  comprises a body portion  126 ,  128 , respectively, made of a non-ferrous (non-magnetic) material. Each body portion  126 ,  128  includes a plurality of paired and matching openings  130 ,  132 . When discs  122 ,  124  are placed in abutting position, the paired and matching openings  130 ,  132  are aligned. In the illustrated embodiment of  FIGS. 12-14 , four openings  130 ,  132  are circular though other shapes are certainly possible as those skilled in the art will recognize. 
   A pair of ferrous (magnetic) washers  134 ,  136  are mounted to each corresponding opening  130 ,  132 , respectively are magnetized whereby one flat surface is a north magnetic pole  24  while the other flat surface is a south magnetic pole  26 . Each of the paired and matching washers  134  and  136  are positioned whereby those surfaces of said washers abutting skin  18  are of opposing poles. The key to the invention is that the surfaces of paired and matching ferrous washers  134 ,  136  abutting skin  18  must be opposing poles. Center holes  135  and  137  extend through the centers of each ferrous washer  134 ,  136 , respectively. 
   To practice the invention, the user first determines the precise location of the corresponding plurality of spots  30  to be located under a patient&#39;s skin  18 . Skin  18  is opened and inner disc  124  is positioned whereby each of the plurality of spots  30  is matched with one of the corresponding plurality of paired center holes  135 ,  137 . Skin  18  is then re-positioned over inner disc  124  with an axis of said ferrous washer  136  oriented perpendicular to skin  18 . Skin  18  will heal naturally over inner disc  124 . 
   The outer disc  126  is aligned with inner disc  124  using methods previously described. Needles  19  are inserted through holes  135 ,  137  and into, for example tube  140 , or directly into the skin, or into mechanisms such as those described previously. Each of the plurality of paired holes  135 ,  137  can lead to a common dispensing chamber, or to differing chambers as desired and predetermined by the medical facts relating to a particular patient. 
   Those skilled in the art will recognize that the present invention is not meant to be limited to the specific shapes and structures described. Other shapes and structures can be employed without departing from the scope of the intended invention. In addition, the present invention is useful in accomplishing other medically related tasks. For example, other uses could include providing a battery check on an implanted battery powered medical device or locating an identification chip now implanted in family pets are certainly contemplated within the scope of the present invention. 
   Although only certain embodiments have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.