Patent Publication Number: US-2013253256-A1

Title: Apparatuses, systems, and methods for use and transport of magnetic medical devices with transport fixtures or safety cages

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention relates generally to magnetic medical devices and, more particularly, but not by way of limitation, to apparatuses, systems, and methods for use and transport of magnetic platforms or positioning apparatuses (that are configured to be magnetically coupled to medical devices) with spacers or safety cages, and/or transport fixtures. 
     2. Description of Related Art 
     For illustration, the background is described with respect to medical procedures (e.g., surgical procedures), which can include laparoscopy, transmural surgery, and endoluminal surgery, including, for example, natural orifice transluminal endoscopic surgery (NOTES), single-incision laparoscopic surgery (SILS), and single-port laparoscopy (SLP). 
     Compared with open surgery, laparoscopy can result in significantly less pain, faster convalescence and less morbidity. NOTES, which can be an even less-invasive surgical approach, may achieve similar results. However, issues such as eye-hand dissociation, a two-dimensional field-of-view, instrumentation with limited degrees of freedom, and demanding dexterity requirements can pose challenges for many laparoscopic and endoscopic procedures. One limitation of laparoscopy can be the fixed working envelope surrounding each trocar. As a result, multiple ports may be used to accommodate changes in position of the instruments or laparoscope, for example, to improve visibility and efficiency. However, the placement of additional working ports may contribute to post-operative pain and increases risks, such as additional bleeding and adjacent organ damage. 
     The following published patent applications include information that may be useful in understanding the present medical devices, systems, and methods: (1) International Application No. PCT/US2009/063987, filed on Nov. 11, 2009, and published as WO 2010/056716; (2) U.S. patent application Ser. No. 10/024,636, filed Dec. 14, 2001, and published as Pub. No. US 2003/0114731; (3) U.S. patent application Ser. No. 10/999,396, filed Nov. 30, 2004, published as Pub. No. US 2005/0165449, and issued as U.S. Pat. No. 7,429,259; (4) U.S. patent application Ser. No. 11/741,731, filed Apr. 28, 2007, published as Pub. No. US 2007/0255273 and issued as U.S. Pat. No. 7,691,103; (5) U.S. patent application Ser. No. 12/146,953, filed Jun. 26, 2008, and published as Pub. No. US 2008/0269779; (6) International Patent Application No. PCT/US10/21292, filed Jan. 16, 2010, and published as WO 2010/083480. 
     SUMMARY 
     This disclosure includes embodiments of apparatuses, systems, and methods. 
     Some embodiments of the present apparatuses (e.g., for use with a magnetic platform configured to be magnetically coupled to a medical device disposed within a body cavity of a patient through a tissue) comprise: a spacer having a coupling portion and a ridge defining an interior region, the coupling portion configured to be coupled to the magnetic platform such that a user can grasp the magnetic platform with at least a part of the user&#39;s hand disposed in the interior region. In some embodiments, the ridge of the spacer has an outer surface that defines an outer perimeter of the spacer, and an inner surface that defines the interior region. In some embodiments, the spacer includes a bottom surface configured to contact a surface on which the magnetic platform is disposed if the spacer is coupled to the magnetic platform. In some embodiments, the bottom surface is substantially planar. In some embodiments, the bottom surface is curved. In some embodiments, the spacer includes a curved surface between the bottom surface and the outer surface. In some embodiments, the ridge has a top end and a bottom end, and the cross-sectional thickness between the inner surface and the outer surface is larger at the bottom end than at the top end. In some embodiments, the ridge has a triangular cross-sectional shape. In some embodiments, the ridge includes one or more projections extending from the outer surface and away from the interior region. In some embodiments, the one or more projections includes a single projection extending around the outer perimeter of the spacer. In some embodiments, the coupling portion is configured to be coupled to the magnetic platform such that the strength of the magnetic field at the outermost point on the outer surface of the ridge is less than half of the strength of the strongest magnetic field immediately adjacent to the magnetic platform. In some embodiments, the coupling portion is configured to be coupled to the magnetic platform such that the strength of the magnetic field at the outermost point on the outer surface of the ridge is less than 150 Gauss. 
     In some embodiments of the present apparatuses, the ridge has a top end and a bottom end, and the cross-sectional thickness between the inner surface and the outer surface is substantially constant along a majority of a height of the ridge between the bottom end and the top end. In some embodiments, the ridge has a rectangular cross-sectional shape. In some embodiments, the ridge is circular. In some embodiments, the ridge has an outer transverse dimension of at least 6 inches. In some embodiments, the coupling portion is configured to be coupled to the magnetic platform such that the magnetic platform is tiltable relative to the spacer and at least a portion of the platform is substantially fixed laterally relative to the spacer. In some embodiments, the coupling portion of the spacer is coupled to a magnetic platform that is configured to be magnetically coupled to a medical device disposed within a body cavity of a patient through a tissue. Some embodiments further comprise: a second identical spacer coupled to a magnetic platform that is configured to be magnetically coupled to a medical device disposed within a body cavity of a patient through a tissue; where the magnetic platforms and spacers are configured such that if placed on a surface with the outer surfaces of the spacers in contact, the attractive force between the magnetic platforms will not exceed 2000 grams. 
     Some embodiments of the present apparatuses (e.g., for transport and/or storage of a magnetic platform configured to be magnetically coupled to a medical device disposed within a body cavity of a patient through a tissue) comprise: a sidewall configured to define an interior region sized to receive a magnetic platform that is configured to be magnetically coupled to a medical device disposed within a body cavity of a patient through a tissue; and a plurality of projections extending into the interior region and configured to hold a magnetic platform in the interior region in a substantially fixed orientation relative to the sidewall. In some embodiments, the sidewall comprises a plurality of openings extending through the sidewall. In some embodiments, the plurality of projections are configured to hold a magnetic platform received in the interior region such that the magnetic platform is spaced apart from the sidewall. In some embodiments, the plurality of projections are configured to hold the magnetic platform such that the strength of the magnetic field immediately outside a non-horizontal portion of the sidewall is less than 200 Gauss. In some embodiments, a magnetic platform is received in the interior region. Some embodiments further comprise: a second identical apparatus in which a second identical magnetic platform is received; where the magnetic platforms and apparatuses are configured such that if the apparatuses are placed on a horizontal planar surface with their sidewalls in contact, the attractive force between the magnetic platforms will not exceed 2000 grams. In some embodiments, the interior region is rectangular. In some embodiments, the apparatus further comprises: a first member comprising a first portion of the sidewall; and a second member comprising a second portion of the sidewall; where the first and second members are coupled together to be movable between: (i) a closed configuration in which the first and second members cooperate to define the interior region; and (ii) an open configuration in which a magnetic platform can be inserted into or removed from the interior region. In some embodiments, the first member is movably coupled to the second member by a hinge. In some embodiments, the first member is unitary with the second member. In some embodiments, at least one of the plurality of protrusions is coupled to the first member, and at least one of the plurality of protrusions is coupled to the second member. In some embodiments, the at least one protrusion coupled to the first member comprises a first plurality of ribs, and the at least one protrusion coupled to the second member comprises a second plurality of ribs. In some embodiments, the first plurality of ribs and second plurality of ribs are configured to hold a magnetic platform in a substantially fixed position relative to the sidewall if the first and second members are in the closed configuration. In some embodiments, the first plurality of ribs is unitary with the first member, and the second plurality of ribs is unitary with the second member. 
     In some embodiments of the present apparatuses, the interior region is circular. In some embodiments, the sidewall defines a cylinder. Some embodiments further comprise: one or more supports coupled to the sidewall and configured to support the magnetic platform in the interior region. Some embodiments further comprise: a lid configured to be coupled to sidewall; and one or more projections coupled to the lid and configured to extend into the interior region if the lid is coupled to the sidewall; where the apparatus is configured to substantially fix the position of a magnetic platform received in the interior region between the one or more projections coupled to the lid and the one or more supports coupled to the sidewall. In some embodiments, at least one of the one or more projections coupled to the lid comprises a tip biased in a direction that extends into the interior region if the lid is coupled to the sidewall. 
     Any embodiment of any of the present apparatuses, systems, and methods can consist of or consist essentially of—rather than comprise/include/contain/have—any of the described steps, elements, and/or features. Thus, in any of the claims, the term “consisting of” or “consisting essentially of” can be substituted for any of the open-ended linking verbs recited above, in order to change the scope of a given claim from what it would otherwise be using the open-ended linking verb. 
     Details associated with the embodiments described above and others are presented below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following drawings illustrate by way of example and not limitation. For the sake of brevity and clarity, every feature of a given structure is not always labeled in every figure in which that structure appears. Identical reference numbers do not necessarily indicate an identical structure. Rather, the same reference number may be used to indicate a similar feature or a feature with similar functionality, as may non-identical reference numbers. The figures are drawn to scale (unless otherwise noted), meaning the sizes of the depicted elements are accurate relative to each other for at least the embodiment depicted in the figures. 
         FIG. 1  depicts a graphical representation of one of the present medical devices positioned within a body cavity of a patient and magnetically coupled to a positioning apparatus that is located outside the cavity. 
         FIG. 2  is an end view of the medical device and positioning apparatus shown in  FIG. 1 . 
         FIGS. 3A-3B  depict a bottom view and a side cross-sectional view, respectively, respectively, of an embodiment of the positioning apparatus shown in  FIG. 1 . 
         FIG. 4  depicts a perspective view of an alternate positioning apparatus. 
         FIG. 5  depicts a perspective view of a first embodiment of the present spacer apparatuses that is configured to be coupled to the positioning apparatus of  FIG. 4 . 
         FIG. 6  depicts a side view of the spacer apparatus of  FIG. 5 . 
         FIG. 7  depicts a perspective view of the spacer apparatus of  FIG. 5  coupled to the positioning apparatus of  FIG. 4 . 
         FIGS. 8A and 8B  depict perspective and side views, respectively, of a second embodiment of the present spacer apparatuses. 
         FIGS. 9 and 10  depict perspective views of a first embodiment of the present enclosure apparatuses in closed and open configurations, respectively. 
         FIGS. 10-14  depict various views of a second embodiment of the present enclosure apparatuses. 
     
    
    
     DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     The term “coupled” is defined as connected, although not necessarily directly, and not necessarily mechanically; two items that are “coupled” may be unitary with each other. The terms “a” and “an” are defined as one or more unless this disclosure explicitly requires otherwise. The term “substantially” is defined as largely but not necessarily wholly what is specified (and includes what is specified; e.g., substantially 90 degrees includes 90 degrees and substantially parallel includes parallel), as understood by a person of ordinary skill in the art. 
     The terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”) and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a device or kit that “comprises,” “has,” “includes” or “contains” one or more elements possesses those one or more elements, but is not limited to possessing only those elements. Likewise, a method that “comprises,” “has,” “includes” or “contains” one or more steps possesses those one or more steps, but is not limited to possessing only those one or more steps. 
     Further, a device or system that is configured in a certain way is configured in at least that way, but it can also be configured in other ways than those specifically described. 
     Referring now to the drawings, shown in  FIGS. 1 and 2  by reference numeral  10  is one embodiment of a system for medical procedures that can be used with the present invention. System  10  is shown in conjunction with a patient  14 , and more particularly in  FIG. 1  is shown relative to a longitudinal cross-sectional view of the ventral cavity  18  of a human patient  14 , and in  FIG. 2  is shown relative to a transverse cross-sectional view of the ventral cavity of the patient. For brevity, cavity  18  is shown in simplified conceptual form without organs and the like. Cavity  18  is at least partially defined by wall  22 , such as the abdominal wall, that includes an interior surface  26  and an exterior surface  30 . The exterior surface  30  of wall  22  can also be an exterior surface  30  of the patient  14 . Although patient  14  is shown as human in  FIGS. 1 and 2 , various embodiments of the present invention (including the version of system  10  shown in  FIGS. 1 and 2 ) can also be used with other animals, such as in veterinary medical procedures. 
     Further, although system  10  is depicted relative to ventral cavity  18 , system  10  and various other embodiments of the present invention can be utilized in other body cavities of a patient, human or animal, such as, for example, the thoracic cavity, the abdominopelvic cavity, the abdominal cavity, the pelvic cavity, and other cavities (e.g., lumens of organs such as the stomach, colon, or bladder of a patient). In some embodiments of the present methods, and when using embodiments of the present devices and systems, a pneumoperitoneum may be created in the cavity of interest to yield a relatively-open space within the cavity. 
     As shown in  FIGS. 1 and 2 , system  10  comprises a positioning apparatus or magnetic platform  34  and a medical device  38 ; the apparatus is configured to magnetically position the device with a body cavity of a patient. In some embodiments, apparatus  34  can be described as an exterior apparatus and/or external unit and device  38  as an interior device and/or internal unit due the locations of their intended uses relative to patients. As shown, apparatus  34  can be positioned outside the cavity  18  near, adjacent to, and/or in contact with the exterior surface  30  of the patient  14 . Device  38  is positionable (can be positioned), and is shown positioned, within the cavity  18  of the patient  14  and near, adjacent to, and/or in contact with the interior surface  26  of wall  22 . Device  38  can be inserted or introduced into the cavity  18  in any suitable fashion. For example, the device  18  can be inserted into the cavity through a puncture (not shown) in wall  22 , through a tube or trocar (not shown) extending into the cavity  18  through a puncture or natural orifice (not shown), or may be inserted into another portion of the patient  14  and moved into the cavity  18  with apparatus  34 , such as by the methods described in this disclosure. If the cavity  18  is pressurized, device  38  can be inserted or introduced into the cavity  18  before or after the cavity  18  is pressurized. 
     Additionally, some embodiments of system  10  include a version of device  38  that has a tether  42  coupled to and extending away from the device  38 . In the depicted embodiment, tether  42  extends from device  38  and out of the cavity  18 , for example, through the opening (not shown) through which device  38  is introduced into the cavity  18 . The tether  42  can be flexible and/or elongated. In some embodiments, the tether  42  can include one or more conduits for fluids that can be used, for example, for actuating a hydraulic cylinder or irrigating a region within the cavity  18 . In some embodiments, the tether  42  can include one or more conductors for enabling electrical communication with the device  38 . In some embodiments, the tether  42  can include one or more conduits for fluid and one or more conductors. In some embodiments, the tether does not include a conduit or conductor and, instead, includes a cord for positioning, moving, or removing device  38  from the cavity  18 . The tether  14 , for example, can be used to assist in positioning the device  34  while the device  34  is magnetically coupled to the apparatus  38 , or to remove the device  34  from the cavity  18  when device  38  is not magnetically coupled to apparatus  34 . 
     As is discussed in more detail below, apparatus  34  and device  38  can be configured to be magnetically couplable to one another such that device  38  can be positioned or moved within the cavity  18  by positioning or moving apparatus  34  outside the cavity  18 . “Magnetically couplable” means capable of magnetically interacting so as to achieve a physical result without a direct physical connection. Examples of physical results are causing device  38  to move within the cavity  18  by moving apparatus  34  outside the cavity  18 , and causing device  38  to remain in a position within the cavity  18  or in contact with the interior surface  26  of wall  22  by holding apparatus  34  in a corresponding position outside the cavity  18  or in contact with the exterior surface  30  of wall  22 . Magnetic coupling can be achieved by configuring apparatus  34  and device  38  to cause a sufficient magnetic attractive force between them. For example, apparatus  34  can comprise one or more magnets (e.g., permanent magnets, electromagnets, or the like) and device  38  can comprise a ferromagnetic material. In some embodiments, apparatus  34  can comprise one or more magnets, and device  38  can comprise a ferromagnetic material, such that apparatus  34  attracts device  38  and device  38  is attracted to apparatus  34 . In other embodiments, both apparatus  34  and device  38  can comprise one or more magnets such that apparatus  34  and device  38  attract each other. 
     The configuration of apparatus  34  and device  38  to cause a sufficient magnetic attractive force between them can be a configuration that results in a magnetic attractive force that is large or strong enough to compensate for a variety of other factors (such as the thickness of any tissue between them) or forces that may impede a desired physical result or desired function. For example, when apparatus  34  and device  38  are magnetically coupled as shown, with each contacting a respective surface  26  or  30  of wall  22 , the magnetic force between them can compress wall  22  to some degree such that wall  22  exerts a spring or expansive force against apparatus  34  and device  38 , and such that any movement of apparatus  34  and device  38  requires an adjacent portion of wall  22  to be similarly compressed. Apparatus  34  and device  38  can be configured to overcome such an impeding force to the movement of device  38  with apparatus  34 . Another force that the magnetic attractive force between the two may have to overcome is any friction that exists between either and the surface, if any, that it contacts during a procedure (such as apparatus  34  contacting a patient&#39;s skin). Another force that the magnetic attractive force between the two may have to overcome is the force associated with the weight and/or tension of the tether  42  and/or frictional forces on the tether  42  that may resist, impede, or affect movement or positioning of device  38  using apparatus  34 . 
     In some embodiments, device  38  can be inserted into cavity  18  through an access port having a suitable internal diameter. Such access ports includes those created using a conventional laparoscopic trocar, gel ports, those created by incision (e.g., abdominal incision), and natural orifices. Device  38  can be pushed through the access port with any elongated instrument such as, for example, a surgical instrument such as a laparoscopic grasper or a flexible endoscope. 
     In embodiments where the tether  42  is connectable to a power source or a hydraulic source (not shown), the tether can be connected to the power source or the hydraulic source (which may also be described as a fluid source) either before or after it is connected to device  38 . 
     In some embodiments, when device  38  is disposed within cavity  18 , device  38  can be magnetically coupled to apparatus  34 . This can serve several purposes including, for example, to permit a user to move device  38  within cavity  18  by moving apparatus  34  outside cavity  18 . The magnetic coupling between the two can be affected by a number of factors, including the distance between them. For example, the magnetic attractive force between device  38  and apparatus  34  increases as the distance between them decreases. As a result, in some embodiments, the magnetic coupling can be facilitated by temporarily compressing the tissue (e.g., the abdominal wall) separating them. For example, after device  38  has been inserted into cavity  18 , a user (such as a surgeon) can push down on apparatus  34  (and wall  22 ) and into cavity  18  until apparatus  34  and device  38  magnetically couple. 
     In  FIGS. 1 and 2 , apparatus  34  and device  38  are shown at a coupling distance from one another and magnetically coupled to one another such that device  38  can be moved within the cavity  18  by moving apparatus  34  outside the outside wall  22 . The “coupling distance” between two structures (e.g., apparatus  34  and device  38 ) is defined as a distance between the closest portions of the structures at which the magnetic attractive force between them is great enough to permit them to function as desired for a given application. 
     Referring now to  FIGS. 3A and 3B , a bottom view and a side cross-sectional view are shown, respectively, of an embodiment of apparatus  34 . Apparatus  34  has a width  50 , a depth  54 , and a height  58 , and includes a housing  46 . The apparatus (and, more specifically, housing  46 ) is configured to support, directly or indirectly, at least one magnetic assembly in the form of one or more magnetic field sources. In the embodiments shown, apparatus  34  is shown as including a first magnetic field source  62   a  and a second magnetic field source  62   b . Each magnetic field source  62   a ,  62   b  has a coupling end  66  and a distal end  70 . As described in more detail below, the coupling ends face device  38  when apparatus  34  and device  38  are magnetically coupled. The depicted embodiment of housing  46  of apparatus  34  also includes a pair of guide holes  68  extending through housing  46  for guiding, holding, or supporting various other devices or apparatuses, as described in more detail below. In other embodiments, the housing of apparatus  34  can have any other suitable number of guide holes  68  such as, for example, zero, one, three, four, five, or more guide holes  68 . In some embodiments, housing  46  comprises a material that is minimally reactive to a magnetic field such as, for example, plastic, polymer, fiberglass, or the like. In other embodiments, housing  46  can be omitted or can be integral with the magnetic field sources such that the apparatus is, itself, a magnetic assembly comprising a magnetic field source. 
     Magnets, in general, have a north pole (the N pole) and a south pole (the S pole). In some embodiments, apparatus  34  can be configured (and, more specifically, its magnetic field sources can be configured) such that the coupling end  66  of each magnetic field source is the N pole and the distal end  70  of each magnetic field source is the S pole. In other embodiments, the magnetic field sources can be configured such that the coupling end  66  of each magnetic field source is the S pole and the distal end  70  of each magnetic field source is the N pole. In other embodiments, the magnetic field sources can be configured such that the coupling end of the first magnetic field source  62   a  is the N pole and the recessed end of the first magnetic field source  62   a  is the S pole, and the coupling end of the second magnetic field source  62   b  is the S pole and the recessed end of the second magnetic field source  62   b  is the N pole. In other embodiments, the magnetic field sources can be configured such that the coupling end of the first magnetic field source  62   a  is the S pole and its recessed end is the N pole, and the coupling end of the second magnetic field source  62   b  is the N pole and its recessed end is the S pole. 
     In the embodiment shown, each magnetic field source includes a solid cylindrical magnet having a circular cross section. In other embodiments, each magnetic field source can have any suitable cross-sectional shape such as, for example, rectangular, square, triangular, fanciful, or the like. In some embodiments, each magnetic field source comprises any of: any suitable number of magnets such as, for example, one, two, three, four, five, six, seven, eight, nine, ten, or more magnets; any suitable number of electromagnets such as, for example, one, two, three, four, five, six, seven, eight, nine, ten or more electromagnets; any suitable number of pieces of ferromagnetic material such as, for example, one, two, three, four, five, six, seven, eight, nine, ten or more pieces of ferromagnetic material; any suitable number of pieces of paramagnetic material such as, for example, one, two, three, four, five, six, seven, eight, nine, ten or more pieces of paramagnetic material; or any suitable combination of magnets, electromagnets, pieces of ferromagnetic material, and/or pieces of paramagnetic material. 
     In some embodiments, each magnetic field source can include four cylindrical magnets (not shown) positioned in end-to-end in linear relation to one another, with each magnet having a height of about 0.5 inch and a circular cross-section that has a diameter of about 1 inch. In these embodiments, the magnets can be arranged such that the N pole of each magnet faces the S pole of the next adjacent magnet such that the magnets are attracted to one another and not repulsed. 
     In some embodiments, device  38  can also include one or more magnets or other magnetically-attractive elements that can be attracted to magnetic field sources  62   a  and  62   b  to enable magnetic coupling between apparatus  34  and  38 . 
     Examples of suitable magnets can include: flexible magnets; Ferrite, such as can comprise Barium or Strontium; AlNiCo, such as can comprise Aluminum, Nickel, and Cobalt; SmCo, such as can comprise Samarium and Cobalt and may be referred to as rare-earth magnets; and NdFeB, such as can comprise Neodymium, Iron, and Boron. In some embodiments, it can be desirable to use magnets of a specified grade, for example, grade 40, grade 50, or the like. Such suitable magnets are currently available from a number of suppliers, for example, Magnet Sales &amp; Manufacturing Inc., 11248 Playa Court, Culver City, Calif. 90230 USA; Amazing Magnets, 3943 Irvine Blvd. #92, Irvine, Calif. 92602; and K &amp; J Magnetics Inc., 2110 Ashton Dr. Suite 1A, Jamison, Pa. 18929. In some embodiments, one or more magnetic field sources can comprise ferrous materials (e.g., steel) and/or paramagnetic materials (e.g., aluminum, manganese, platinum). 
     In some embodiments, apparatus  34  and device  38  can be configured to have a minimum magnetic attractive force or “coupling force” at a certain distance. For example, in some embodiments, apparatus  34  and device  38  can be configured such that at a distance of 50 millimeters between the closest portions of apparatus  34  and device  38 , the magnetic attractive force between apparatus  34  and device  38  is at least about: 20 grams, 25 grams, 30 grams, 35 grams, 40 grams, or 45 grams. In some embodiments, apparatus  34  and device  38  can be configured such that at a distance of about 30 millimeters between the closest portions of apparatus  34  and device  38 , the magnetic attractive force between them is at least about: 25 grams, 30 grams, 35 grams, 40 grams, 45 grams, 50 grams, 55 grams, 60 grams, 65 grams, 70 grams, 80 grams, 90 grams, 100 grams, 120 grams, 140 grams, 160 grams, 180 grams, or 200 grams. In some embodiments, apparatus  34  and device  38  can be configured such that at a distance of about 15 millimeters between the closest portions of apparatus  34  and device  38 , the magnetic attractive force between them is at least about: 200 grams, 250 grams, 300 grams, 350 grams, 400 grams, 45 grams, 500 grams, 550 grams, 600 grams, 650 grams, 700 grams, 800 grams, 900 grams, or 1000 grams. In some embodiments, apparatus  34  and device  38  can be configured such that at a distance of about 10 millimeters between the closest portions of apparatus  34  and device  38 , the magnetic attractive force between them is at least about: 500 grams, 1000 grams, 2000 grams, 2200 grams, 2400 grams, 2600 grams, 2800 grams, 3000 grams, 3200 grams, 3400 grams, 3600 grams, 3800 grams, or 4000 grams. 
       FIG. 4  depicts a perspective view of an alternate positioning apparatus or magnetic platform  34   a . Apparatus  34   a  is substantially similar to apparatus  34 , with the primary exception that housing  46   a  has a distal end  70   a  that is enlarged relative to coupling end  66   a  to facilitate being grasped by a user&#39;s hand. 
     Referring now to  FIGS. 5-7 ,  FIG. 5  depicts a perspective view of a first embodiment  100  of the present spacer apparatuses that is configured to be coupled to the apparatus  34   a ;  FIG. 6  depicts a side view of spacer  100 ; and  FIG. 7  depicts a perspective view of spacer  100  coupled to apparatus  34   a . In the embodiment shown, spacer  100  has a coupling portion  104  and a ridge  108  defining an interior region  112 . Coupling portion  104  is configured to be coupled to apparatus or platform  34   a  (e.g., to coupling end  66   a , as in the embodiment shown) such that a user can grasp apparatus  34   a  with at least a part of the user&#39;s hand (e.g., up to all of the user&#39;s hand) disposed in interior region  112  (e.g., such that ridge  108  may protect the user&#39;s hand from impacting adjacent apparatuses  34   a  and/or certain other objects to which apparatus  34   a  may be attracted). In the embodiment shown, ridge  108  has an outer surface  116  that defines an outer perimeter of the spacer, and an inner surface  120  that defines the interior region (e.g., defines a cylindrical interior region, as in the embodiment shown). 
     In the embodiment shown, spacer  100  includes a bottom surface  124  configured to contact a surface (e.g., the skin of a patient&#39;s abdomen during use, a shelf during storage and/or cleaning, and/or the like) on which a magnetic platform (e.g., apparatus  34   a ) is disposed if the spacer is coupled to the magnetic platform. In the embodiment shown, bottom surface  124  is substantially planar. In other embodiments, the bottom surface can be curved (e.g., concave) to facilitate sliding along a surface. For example, during laparoscopic surgery, a patient&#39;s abdomen may be pressurized and become notably convex, such that the bottom surface of the spacer can be made concave to more closely correspond to the shape of the patient&#39;s pressurized abdomen to increase the surface area of the bottom surface that contacts the patient&#39;s skin. In the embodiment shown, spacer  100  also includes a curved surface  128  (e.g., a filet) between bottom surface  124  and outer surface  116 , such as, for example, to facilitate sliding relative to a patient&#39;s skin during use. 
     In the embodiment shown, ridge  108  is circular (when viewed from the top). In the embodiment shown, ridge  108  has a top end  132  and a bottom end  136 , and the cross-sectional thickness  140  between inner surface  120  and outer surface  116  is larger at bottom end  136  than at top end  132 . For example, in the embodiment shown, ridge  108  has a triangular cross-sectional shape (e.g., at any point along ridge  108 , as in the embodiment shown which has a substantially constant cross-sectional shape). In some embodiments, ridge  108  includes one or more projections extending from the outer surface and away from the interior region. For example, in the embodiment shown, ridge  108  includes a single projection  144  extending from outer surface  116  and away from interior region  112  around the outer perimeter of spacer  100 . In some embodiments, ridge  108  has an outer transverse dimension of at least 6 inches. For example, in the embodiment shown, ridge  108  has a diameter  148  measured to the outermost portion of outer surface  116  of at least 4 inches (e.g., equal to, or between any two of: 4, 5, 6, 7, 8, 9, 10, 11, 12, or more inches). In some embodiments, ridge  108  has a non-circular shape (e.g., ellipse, rectangular, or other shape corresponding to the outer shape of the coupling end of apparatus  34   a ) with a first transverse dimension (e.g., minor diameter) of at least 5 inches and a second transverse dimension (e.g., major diameter) of at least 7 inches. For example, in some embodiments, ridge  108  is configured to have an outer perimeter that is spaced from the outer perimeter of the coupling end of apparatus  34   a  by a distance of at least 1.5 inches (e.g., 2 inches or more). 
     In the embodiment shown, coupling portion  104  is configured to be coupled to apparatus  34   a  such that the strength of the magnetic field (of the magnetic field source(s) of apparatus  34   a ) at the outermost (relative to the center of interior region  112 ) point (e.g., point  152 ) on outer surface  116  of the ridge is less than half of the strength of the strongest magnetic field immediately adjacent to apparatus  34   a  (e.g., at a point  156  on the outer surface  160  of apparatus  34   a  in the same horizontal (relative to apparatus  34   a ) plane as the outermost point  152  of spacer  100 ). Stated another way, spacer  100  is configured to be coupled to apparatus  34   a  such that the distance between outer surface  116  of ridge  108  and outer surface  160  of apparatus  34   a  is large enough that, at any point on along the outermost perimeter of the spacer (e.g., the intersection of outer surface  116  and curved surface  128  in the embodiment shown), the strength of the magnetic field of apparatus  34   a  is less than half (e.g., equal to, or between any two of: 40%, 30%, 20%, or less) of its strongest point on surface  160 . For example, in some embodiments, coupling portion  104  is configured to be coupled to apparatus  34   a  such that the strength of the magnetic field (of the magnetic field source(s) of apparatus  34   a ) at the outermost (relative to the center of interior region  112 ) point (e.g., point  152 ) on outer surface  116  of the ridge is less than 200 Guass (e.g., less than, or between any two of: 200, 150, and 100 Guass). 
     In the embodiment shown, coupling portion  104  is configured to be coupled to the apparatus  34   a  such that if the spacer and the apparatus are disposed on a horizontal planar surface such that the spacer (e.g., outer surface  116 ) contacts an identical second spacer (e.g., the outer surface  116  of the identical second spacer) that is coupled to an identical second magnetic platform  34   a , an attractive force between the two magnetic platforms will not exceed 2000 grams. Stated another way, spacer  100  is configured (e.g., coupling portion  104  is positioned relative to outer surface  116  of ridge  108 ) such that if two spacers  100  are coupled to apparatuses  34   a  and the spacers are positioned in contact with each other, the attractive force (the force that a user must overcome to separate one apparatus/spacer assembly from the other apparatus/spacer assembly) will not exceed 2000 grams (e.g., equal to, or between any two of: 1500 grams, 1000 grams, 500 grams, or less). 
     Some of the present embodiments comprise two identical spacers (e.g.,  100 ) coupled to a identical magnetic platforms (e.g.,  34   a ); where the magnetic platforms and spacers are configured such that if placed on a surface with the outer surfaces of the spacers in contact, the attractive force between the magnetic platforms will not exceed 2000 grams. 
     In the embodiment shown, coupling portion  104  includes an opening  164  configured (e.g., sized and shaped) to receive coupling end  66   a  of apparatus  34   a . In some embodiments, coupling portion  104  is configured to be coupled to apparatus  34   a  such that apparatus  34   a  is tiltable relative to spacer  100  and at least a portion of apparatus is substantially fixed laterally relative to the spacer. For example, in the embodiment shown, opening  164  is larger than coupling end  66   a  of apparatus  34   a , and/or a bottom portion  168  of spacer  100  is flexible, such that coupling end  66   a  is prevented from moving laterally more than a minimal distance relative to the spacer, while still permitting distal end  70   a  to move relative to spacer  100  to tilt apparatus  34   a . Spacer  100  can, for example, comprise a non-ferrous and/or magnetically-inert material (e.g., a polymer). 
       FIGS. 8A and 8B  depict perspective and side views, respectively, of a second embodiment  100   a  of the present spacer apparatuses. Spacer  100   a  is substantially similar to spacer  100 , with the primary exception that the cross-sectional thickness  140  is substantially constant along a majority of a height  172  of the ridge between the bottom end  136  and the top end  132  (e.g., ridge  108   a  has a rectangular cross-sectional shape). In the embodiment shown, spacer  100   a  includes a ledge  176  around the bottom end  136  of ridge  108   a  (between curved surface  128   a  and outer surface  116   a ). 
     Referring now to  FIGS. 9 and 10 , shown therein are perspective views of a first embodiment  200  of the present enclosure apparatuses (shown in a closed configuration in  FIG. 9  and an open configuration in  FIG. 10 ). Embodiments of enclosure  200  can, for example, be used for transport, sterilization, and/or storage of magnetic platforms to prevent undesirable magnetic interactions with other magnetic platforms (e.g., to prevent to adjacent magnetic platforms from becoming magnetically attracted to one another to a degree that separation becomes difficult). In the embodiment shown, enclosure  200  comprises: a sidewall  204  configured to define an interior region  208  sized to receive a magnetic platform (apparatus  34   b ); and a plurality of projections  212  extending into the interior region and configured to hold a magnetic platform  34   b  ( FIG. 10 ) in the interior region in a substantially fixed orientation relative to the sidewall. In this embodiment, interior region  208  is rectangular. In the embodiment shown, sidewall  204  comprises a plurality of openings  216  extending through the sidewall. Openings  216  can, for example, be used to introduce a cleaning and/or sterilizing agent (e.g., liquid) into interior region  208  to clean and/or sterilize an apparatus  34   b  disposed in the enclosure. In the embodiment shown, apparatus  34   b  is substantially similar to apparatuses  34  and  34   a , with the primary difference that distal end  70   b  has a different shape that is enlarged relative to coupling end  66   b , but not as much so as distal end  70   a  of apparatus  34   a  relative to coupling end  66   a . Sidewall  204  can comprise, for example, a polymer (e.g., a substantially rigid plastic). 
     In the embodiment shown, projections  212  are configured to hold a magnetic platform (e.g., apparatus  34   b ) received in the interior region (as shown in  FIG. 10 ) such that the magnetic platform apparatus is spaced apart from sidewall  204 . In the embodiment shown, enclosure  200  comprises: a first member  220  comprising a first portion  224  of sidewall  204 ; and a second member  228  comprising a second portion  232  of sidewall  204 . In this embodiment, first member  220  and second member  228  are coupled together to be movable between: (i) a closed configuration ( FIG. 9 ) in which the first and second members cooperate to define the interior region; and (i) an open configuration ( FIG. 10 ) in which a magnetic platform (e.g., apparatus  34   b ) can be inserted into or removed from the interior region. First and second members  220  and  228  can be coupled together by a hinge  234 . In other embodiments, first member  220  can be unitary with second member  228  (e.g., coupled together by a “living hinge” unitary with first and second members  220  and  228 ). 
     In the embodiment shown, at least one protrusion  212  is coupled to first member  220 , and at least one protrusion  212  is coupled to second member  228 . In the embodiment shown, the at least one protrusion coupled to the first member comprises a plurality of ribs  236  (e.g., a plurality of intersecting planar ribs extending inward from first portion  224  of sidewall  204 ), and the at least one protrusion coupled to the second member comprises a plurality of ribs  240  (e.g., a plurality of intersecting planar ribs extending inward from second portion  232  of sidewall  204 ). In this embodiment, ribs  236  and ribs  240  are configured to hold a magnetic platform (e.g., apparatus  34   b ) in a substantially fixed position relative to the sidewall if the first and second members are in the closed configuration ( FIG. 10 ). In the embodiment shown, ribs  236  are unitary with first member  220 , and ribs  240  are unitary with second member  228 . As shown, in this embodiment, ribs  236  and ribs  240  are contoured to correspond to the shape of the magnetic platform. In the embodiment shown, enclosure  200  comprises a plurality of latches  242  configured to couple first member  220  to second member  228  in the closed configuration. 
     In some embodiments, projections are configured to hold the magnetic platform (e.g., apparatus  34   b ) such that the strength of the magnetic field immediately outside a non-horizontal portion  244  of sidewall  204  is less than 300 Guass (e.g., less than 250 Gauss, less than 200 Gauss, or less). For example, in the embodiment shown, apparatus  200  is configured such that if apparatus  34   b  is disposed in enclosure  200 , a distance of at least 3.5 centimeters (cm) separates each point on the exterior surface of apparatus  34   b  and the closest point on sidewall  244  (e.g., resulting in a maximum magnetic field strength immediately outside sidewall  244  of 200 Guass or less). 
     In some embodiments, projections  212  are configured to hold a magnetic platform (e.g., apparatus  34   b ) such that if the enclosure is disposed on a horizontal planar surface in contact with an identical second enclosure that is also disposed on the planar surface, and an identical second magnetic platform (e.g., apparatus  34   b ) is received in the second apparatus, an attractive force between the two magnetic platforms will not exceed 2000 grams (e.g., equal to, or between any two of: 1500 grams, 1000 grams, 500 grams, or less). Some of the present embodiments comprise two identical enclosures (e.g.,  200 ) each holding a different one of two identical magnetic platforms (e.g.,  34   b ); where the magnetic platforms and enclosures are configured such that if placed on a surface with the sidewalls of the enclosures in contact, the attractive force between the magnetic platforms will not exceed 2000 grams (e.g., equal to, or between any two of: 1500 grams, 1000 grams, 500 grams, or less). 
       FIGS. 10-14  depict various views of a second embodiment  200   a  of the present enclosure apparatuses. Enclosure  200   a  is similar in some respects to enclosure  200 , with the primary exceptions being that enclosure  200   a  sidewall  204   a  defines a cylinder having a circular interior region  208   a . In some embodiments, enclosure  200   a  comprises one or more supports coupled to sidewall  204   a  and configured to support the magnetic platform (e.g., apparatus  34   b ) in the interior region. For example, in the embodiment shown, enclosure  200   a  comprises a plurality of supports  256  coupled to sidewall  204   a  and configured to support apparatus  34   b  in the interior region (e.g., in a substantially fixed orientation relative to sidewall  204   a ). In this embodiment, sidewall  204   a  and lid  260  each includes a plurality of holes  216   a.    
     In this embodiment, apparatus  200   a  further comprises a lid  260  configured to be coupled to sidewall  204   a , where at least one of the plurality of supports  256  is coupled to the lid and configured to extend into the interior region if the lid is coupled to the sidewall. As shown, in this embodiment, the apparatus is configured to substantially fix the position of a magnetic platform (e.g., apparatus  34   b ) received in the interior region between the at least one support  256  coupled to the lid and the one or more supports  256  coupled to the sidewall. In the embodiment shown, the support  256  coupled to lid  260  comprises a tip or plunger  264  biased in a direction  268  that extends into the interior region if the lid is coupled to the sidewall such that tip  264  is compressed as lid is coupled to sidewall  204   a  to provide downward pressure on magnetic platform  34   b  and thereby securely hold platform  34   b  in interior region. In the embodiment shown, some of supports  256  (bottom supports) extend across the entire interior region to support the magnetic platform  34   b  at a lower end of the interior region, some of supports  256  (side supports) are configured to extend between sidewall  204   a  and magnetic platform  34   b , and at least one support  256  (top support) is configured to extend between lid  260  and magnetic platform  34   b . In the embodiment shown, one of lid  260  and sidewall  204   a  includes a protrusion  272 , and the other of lid  260  and sidewall  204   a  includes an L-shaped grooved  276 , such that lid  260  can be inserted and turned relative to sidewall  204   a  to lock lid  260  relative to sidewall  204   a . In this embodiment, lid  260  includes a handle  280  configured to be used to carry enclosure  200   a  when lid  260  is coupled to sidewall  204   a  (e.g., if a magnetic platform is in the interior region). Supports  256  can comprise, for example, aluminum and/or polymer (e.g., a substantially rigid plastic). 
     Embodiments of the present methods can include coupling each of one or more of the present magnetic platforms (e.g.,  34 ,  34   a ,  34   b ) to an embodiment of the present spacers (e.g.,  100 ,  100   a ), magnetically coupling the magnetic platform to a medical device (e.g., in a body cavity of a patient), disposing one or more of the present magnetic platforms (e.g.,  34 ,  34   a ,  34   b ) in an embodiment of the present enclosures (e.g.,  200 ,  200   a ). For example, multiple ones of the present magnetic platforms ( 34 ,  34   a ,  34   b ) coupled to the present spacers can be used in proximity to one another with a distance (and attractive force) between the magnetic platforms that is limited by the spacers. Similarly, multiple ones of the present magnetic platforms disposed in the present enclosures ( 200 ,  200   a ) can be placed adjacent to one another with a distance (and attractive force) between the magnetic platforms that is limited by the enclosures. 
     The above specification and examples provide a complete description of the structure and use of exemplary embodiments. Although certain embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the scope of this invention. As such, the various illustrative embodiments of the present devices are not intended to be limited to the particular forms disclosed. Rather, they include all modifications and alternatives falling within the scope of the claims, and embodiments other than the one shown may include some or all of the features of the depicted embodiment. For example, components may be combined as a unitary structure, and/or connections may be substituted. Further, where appropriate, aspects of any of the examples described above may be combined with aspects of any of the other examples described to form further examples having comparable or different properties and addressing the same or different problems. Similarly, it will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments. 
     The claims are not intended to include, and should not be interpreted to include, means-plus- or step-plus-function limitations, unless such a limitation is explicitly recited in a given claim using the phrase(s) “means for” or “step for,” respectively.