Patent Publication Number: US-2022218392-A1

Title: Access Devices, Treatment Devices, and Kits Useful for Performing Treatment under Magnetic Resonance Imaging and Related Methods

Description:
RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application No. 63/135,966, filed Jan. 11, 2021. The entire contents of this related application are hereby incorporated by reference into this disclosure. 
    
    
     FIELD 
     The disclosure relates generally to the field of medical devices. More particularly, the disclosure relates to access devices useful in providing access to a bodily passage under magnetic resonance imaging (MRI), treatment devices useful in performing treatment under MRI, kits useful in performing treatment under MRI, and methods of performing interventional medical treatment under MRI. 
     BACKGROUND 
     The field of interventional MRI is gaining wider acceptance and seeing an increase in the number of procedures that can be performed. Interventional procedures conducted under MRI have several benefits over X-Ray-guided interventions. For example, the patient is not exposed to ionizing radiation. Also, MRI provides the ability to characterize tissue and functional flow during an interventional procedure. 
     The development of interventional procedures conducted under MRI has been limited as a result of the tools needed to perform these procedures being unavailable. Therefore, patients are required to make multiple visits to treatment facilities to visualize, diagnose, and treat various conditions. In addition, multiple imaging modalities are often needed, which impacts the accuracy of utilizing a magnetic resonance image in directing intervention. For example, when addressing prostate cancer, visualization, biopsy, and treatment are currently completed over the course of three patient visits. At a first visit, a scan is completed using a magnetic resonance scanner to produce an image showing the prostate and any abnormalities. The patient then leaves the facility and awaits a review of the image. If abnormalities exist, a second patient visit will occur such that a biopsy sample of the abnormal tissue can be completed. Currently, software is used to fuse the magnetic resonance image with the procedural ultrasound to provide guidance in conducting the biopsy. This fusion decreases the value of the diagnostic magnetic resonance image. The patient then leaves the facility again and awaits a review of the biopsy sample to determine whether further treatment is required (e.g., if the review results in a positive prostate cancer diagnosis). If further treatment is required, the patient will visit the facility a third time such that treatment can be performed. Completion of these three patient visits can take months, prevents the patient from receiving rapid treatment, and increases the overall costs associated with treatment. Furthermore, software used to fuse magnetic resonance images with other images (e.g., those obtained via ultrasound) have drawbacks, such as potential image overlay issues and the potential for compression shifting of tissues (e.g., prostate). 
     A need exists, therefore, for new and improved access devices useful in providing access to a bodily passage under MRI, treatment devices useful in performing treatment under MRI, kits useful in performing treatment under MRI, and methods of performing interventional medical treatment under MRI. 
     SUMMARY OF SELECTED EXAMPLE EMBODIMENTS 
     Various example access devices useful in providing access to a bodily passage under MRI, treatment devices useful in performing treatment under MRI, kits useful in performing treatment under MRI, and methods of performing interventional medical treatment under MRI are described herein. 
     An example access device useful in providing access to a bodily under MRI includes an elongate tubular member moveable between a first, unexpanded configuration and a second, expanded configuration. The elongate tubular member has a central lengthwise axis, a proximal end, a distal end, an axial length, and a main body that defines a circumferential wall, a lumen, a proximal opening, a distal opening, and a main body opening. The main body opening is arranged in a spiral relative to the lengthwise axis and extends circumferentially along the circumferential wall. The main body opening extends along the entire axial length of the elongate tubular member from the proximal end to the distal end. 
     An example treatment device useful in performing treatment under MRI comprises an elongate member and a tubular member partially disposed over the elongate member. The elongate member is moveable between a first, unexpanded configuration and a second, expanded configuration. The elongate member has a lengthwise axis, a proximal end, a distal end, an adaptor, and a plurality of tubular members attached to the adaptor. The adaptor is disposed on the proximal end of the elongate member, has a port, and defines a lumen. Each tubular member of the plurality of tubular members has a tubular member proximal end, a tubular member distal end, and a tubular member main body that defines a tubular member lumen and a predefined curve. 
     An example method of performing an interventional medical treatment under MRI comprises positioning a patient within a magnetic resonance scanner; scanning a first portion of the patient using the magnetic resonance scanner; obtaining a magnetic resonance image of the first portion of the patient; identifying a tissue that has predefined characteristics using the magnetic resonance image; while the patient remains positioned within the magnetic resonance scanner used to scan a portion of the patient, advancing a medical device into a bodily passage and to the tissue while scanning a second portion of the patient that includes the medical device using the magnetic resonance scanner; obtaining a magnetic resonance image of the second portion of the patient that includes the medical device; confirming the position of the medical device within the bodily passage; advancing a biopsy device through the medical device and to the tissue while scanning a third portion of the patient that includes the biopsy device using the magnetic resonance scanner; obtaining a magnetic resonance image of the third portion of the patient that includes the biopsy device; confirming the position of the biopsy device; collecting a tissue sample from the tissue using the biopsy device while scanning a fourth portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner; obtaining a magnetic resonance image of the fourth portion of the patient that includes the biopsy device; confirming the tissue sample has been collected; withdrawing the biopsy device and the tissue sample through the medical device; determining whether the tissue sample meets a predefined criterion; if the tissue sample meets the predefined criterion, advancing an anchor member through the medical device through which the biopsy device was advanced and to the tissue while the patient remains positioned within the magnetic resonance scanner; securing the anchor member to the tissue so that the anchor member is attached to the tissue to retain the position of the medical device relative to the tissue; advancing an access device over the medical device and toward the tissue; removing the anchor member from the tissue so that the anchor member is not attached to the tissue; withdrawing the anchor member from the bodily passage; withdrawing the medical device from the bodily passage; advancing a treatment device through the access device and to the tissue; manipulating the tissue using the treatment device; withdrawing the treatment device from the access device; withdrawing the access device from the bodily passage. 
     Another example method of performing an interventional medical treatment under MRI comprises positioning a patient within a magnetic resonance scanner; scanning a first portion of the patient using the magnetic resonance scanner; obtaining a magnetic resonance image of the first portion of the patient; identifying a tissue that has predefined characteristics using the magnetic resonance image; while the patient remains positioned within the magnetic resonance scanner used to scan a portion of the patient, advancing a medical device into a bodily passage and to the tissue while scanning a second portion of the patient that includes the medical device using the magnetic resonance scanner; obtaining a magnetic resonance image of the second portion of the patient that includes the medical device; confirming the position of the medical device within the bodily passage; advancing an anchor member through the medical device and to the tissue while the patient remains positioned within the magnetic resonance scanner; securing the anchor member to the tissue so that the anchor member is attached to the tissue; withdrawing the medical device from the bodily passage; advancing an access device over the anchor member and toward the tissue; removing the anchor member from the tissue; withdrawing the anchor member from the bodily passage; advancing a biopsy device through the access device and to the tissue while scanning a third portion of the patient that includes the biopsy device using the magnetic resonance scanner; obtaining a magnetic resonance image of the third portion of the patient that includes the biopsy device; confirming the position of the biopsy device; collecting a tissue sample from the tissue using the biopsy device while scanning a fourth portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner; obtaining a magnetic resonance image of the fourth portion of the patient that includes the biopsy device; confirming the tissue sample has been collected; withdrawing the biopsy device and the tissue sample through the access device; determining whether the tissue sample meets a predefined criterion; if the tissue sample meets the predefined criterion, advancing a treatment device through the access device and to the tissue; manipulating the tissue using the treatment device; withdrawing the treatment device from the access device; withdrawing the access device from the bodily passage; removing the patient from the magnetic resonance scanner. 
     An example method of performing treatment on a prostate under MRI comprises positioning a patient within a magnetic resonance scanner; scanning a prostate and surrounding tissue of the patient using the magnetic resonance scanner; obtaining a magnetic resonance image of the prostate and surrounding tissue of the patient; identifying a tissue within the magnetic resonance image that has predefined characteristics; while the patient remains positioned within the magnetic resonance scanner used to scan the prostate and surrounding tissue, advancing a medical device into a bodily passage and to the tissue while scanning a first portion of the patient that includes the medical device using the magnetic resonance scanner; obtaining a magnetic resonance image of the second portion of the patient that includes the medical device; confirming the position of the medical device within the bodily passage; advancing a biopsy device through the medical device and to the tissue while scanning a third portion of the patient that includes the biopsy device using the magnetic resonance scanner; obtaining a magnetic resonance image of the third portion of the patient that includes the biopsy device; confirming the position of the biopsy device; collecting a tissue sample from the tissue using the biopsy device while scanning a fourth portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner; obtaining a magnetic resonance image of the fourth portion of the patient that includes the biopsy device; confirming the tissue sample has been collected; withdrawing the biopsy device and the tissue sample through the medical device; determining whether the tissue sample meets a predefined criterion; if the tissue sample meets the predefined criterion, advancing an anchor member through the medical device through which the biopsy device was advanced and to the tissue while the patient remains positioned within the magnetic resonance scanner; securing the anchor member to the tissue so that the anchor member is attached to the tissue to retain the position of the medical device relative to the tissue; advancing an access device over the medical device and toward the tissue; removing the anchor member from the tissue; withdrawing the anchor member from the bodily passage; withdrawing the medical device from the bodily passage; advancing a treatment device through the access device and to the tissue; manipulating the tissue using the treatment device; withdrawing the treatment device from the access device; withdrawing the access device from the bodily passage. 
     An example kit useful in performing treatment under MRI includes an access device and a plurality of treatment devices according to embodiments. 
     Additional understanding of these example access devices, treatment devices, kits, and methods can be obtained by review of the detailed description, below, and the appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partial perspective view of a first example access device. The access device is shown in a first, unexpanded configuration. 
         FIG. 2  is another partial perspective view of the access device illustrated in  FIG. 1 . The access device is shown in a second, expanded configuration. 
         FIG. 3  is a partial perspective view of a first example treatment device. The treatment device is shown in a first, unexpanded configuration. 
         FIG. 4  is another partial perspective view of the treatment device illustrated in  FIG. 3 . The treatment device is shown in a second, expanded configuration. 
         FIG. 5  is a partial perspective view of a second example treatment device. The elongate member of the treatment device is shown in a first, substantially straight configuration. 
         FIG. 6  is another partial perspective view of the treatment device illustrated in  FIG. 5 . The elongate member of the treatment device is shown in a second, curved configuration. 
         FIG. 7  is a partial perspective view of a third example treatment device. The elongate member of the treatment device is shown in a first, substantially straight configuration. 
         FIG. 8  is another partial perspective view of the treatment device illustrated in  FIG. 7 . The elongate member of the treatment device is shown in a second, curved configuration. 
         FIGS. 9A and 9B  show a schematic illustration of an example method of performing treatment under MRI. 
         FIGS. 10A and 10B  show another schematic illustration of an example method of performing treatment under MRI. 
         FIGS. 11A and 11B  show another schematic illustration of an example method of performing treatment under MRI. 
         FIG. 12  shows a magnetic resonance thermometry (MRT) proton resonant frequency (PRF) (MRT-PRF) temperature contour around a copper wire. 
         FIG. 13  illustrates a MRT-PRF temperature contour around a stent. 
         FIG. 14  illustrates a gradient echo pulse sequence used for MRT based on PRF shift method. 
         FIG. 15  illustrates an example kit that includes an example access device and example treatment devices. 
     
    
    
     DETAILED DESCRIPTION OF SELECTED EXAMPLES 
     The following detailed description and the appended drawings describe and illustrate various example access devices useful in performing treatment under MRI, treatment devices useful in performing treatment under MRI, kits useful in performing treatment under MRI, and methods of performing interventional medical treatment under MRI. The description and illustration of these examples are provided to enable one skilled in the art to make and use an access device, a treatment device, a kit, and to practice a method of performing an interventional medical treatment under MRI. They are not intended to limit the scope of the invention, or the protection sought, in any manner. The invention is capable of being practiced or carried out in various ways and the examples described and illustrated herein are merely selected examples of the various ways of practicing or carrying out the invention and are not considered exhaustive. 
     As used herein, the term “attached” refers to one member being secured to another member such that the members do not completely separate from each other during use performed in accordance with the intended use of an item that includes the members in their attached form. 
     As used herein, the term “circumference” refers an external enclosing boundary of a body, element, or feature and does not impart any structural configuration on the body, element, or feature. 
       FIG. 1  illustrates a first example access device  10 . In this example, the access device  10  is an elongate tubular member  12  that is moveable between a first, unexpanded configuration, as shown in  FIG. 1 , and a second, expanded configuration, as shown in  FIG. 2 , as one or more devices are passed through the elongate tubular member  12 . 
     The elongate tubular member  12  has a central lengthwise axis  13 , a proximal end  14 , a distal end  16 , an axial length  17 , and a main body  18  that defines a circumferential wall  20 , a lumen  22 , a proximal opening  24 , a distal opening  26 , and a main body opening  28 . The axial length  17  extends from the proximal end  14  to the distal end  16 . The circumferential wall  20  extends from the proximal end  14  to the distal end  16 . Each of the proximal opening  24  and the distal opening  26  provides access to the lumen  22 . 
     The main body opening  28  extends along the entire axial length  17  of the elongate tubular member  12  from the proximal end  14  to the distal end  16 . However, in alternative embodiments, a main body opening can extend along a portion of the axial length of an elongate tubular member (e.g., between the proximal end and the distal end). The main body opening  28  is arranged in a spiral relative to the lengthwise axis  13  and extends circumferentially along the circumferential wall  20 . The main body opening  28  comprises a slit that extends through the entire wall thickness of the circumferential wall  20  to provide access to the lumen  22 . 
     The elongate tubular member  12  is moveable between the first, unexpanded configuration in which the lumen  22  has a first inside diameter  23 , and the second, expanded configuration in which the lumen  22  has a second inside diameter  25  that is greater than the first inside diameter  23 . Movement of the elongate tubular member  12  from the first, unexpanded configuration to the second, expanded configuration can be accomplished by passing a device through the lumen  22  that has an outside diameter that is greater than the first inside diameter  23  of the lumen  22 . Movement of the elongate tubular member  12  from the second, expanded configuration to the first, unexpanded configuration can be accomplished by removing a device that has an outside diameter that is greater than the first inside diameter  23  of the lumen  22  that is disposed within the lumen  22 . In the first, unexpanded configuration, the main body opening  28  has a first width  29  and in the second, expanded configuration the main body opening  28  has a second width  31  that is greater than the first width. The structural arrangement of the access device  10  is considered advantageous at least because it can be introduced into a bodily passage and expanded after the treatment site has been reached, reducing potential trauma at the treatment site. 
     While a single main body opening  28  has been illustrated, a main body opening included on an elongate tubular member can comprise any suitable number of openings, formed in any suitable manner, and positioned at any suitable location on an elongate tubular member. For example, a main body opening can comprise a plurality of openings arranged in any suitable configuration (e.g., an interrupted spiral) that extends circumferentially along a circumferential wall of an elongate tubular member. Each opening of the plurality of openings can comprise an elongate slit that extends through the entire wall thickness of a circumferential wall to provide access to a lumen of an elongate tubular member. Examples of methods and techniques of forming a main body opening in an elongate tubular member include laser cutting, stamping, die cutting, and any other method or technique considered suitable for a particular embodiment. 
     Optionally, an elastic polymeric sleeve or jacket can be positioned on an outer surface of the elongate tubular member that is moveable with the elongate tubular member between a first, unexpanded configuration and a second, expanded configuration. The polymeric sleeve can extend the along the entire axial length of the elongate tubular member, or along a portion of the axial length of the elongate tubular member. The polymeric sleeve can be reinforced by including polymeric fibers embedded or woven into the sleeve. Optionally the polymeric sleeve can be coated with a lubricious agent to reduce friction during use, as described herein. The polymeric sleeve can be applied to the outer surface of the elongate tubular member using any suitable method or technique and selection of a suitable method or technique can be based on various considerations, including the intended use of the elongate tubular member. Examples of methods and techniques considered suitable to apply a polymeric sleeve to an elongate tubular member include dipping an elongate tubular member in a solvated polymer solution, thermal bonding, extruding a tube over an elongate tubular member, and any other method or technique considered suitable for a particular embodiment. When an extruded tube is included on an elongate tubular member, the extruded tube can optionally be profiled using heat shrink polymer. The heat shrink polymer tubing can then be removed leaving a thin coating of polymer over the elongate tubular member. 
     In the illustrated embodiment, the elongate tubular member  12  can be formed of any suitable MRI compatible material and can include any suitable type and/or number of markers. In the illustrated embodiment, the elongate tubular member  12  is formed of an MRI compatible metal and has a plurality of passive markers  30  disposed along the axial length  17  of the elongate tubular member  12  and at the distal end  16  that allow for visualization of the elongate tubular member  12  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). In an alternative embodiment, an elongate tubular member can be formed of a shape memory material (e.g., Nitinol) such that it expands upon removal from a restraining tube allowing it to move from a first, unexpanded configuration to a second, expanded configuration due to being biased to the second, expanded configuration or such that it can be moved to the second, expanded configuration using a balloon. Markers of the plurality of passive markers  30  are advantageously formed of a magnetically susceptible material, such as a paramagnetic material or a ferromagnetic material. 
       FIGS. 3 and 4  illustrate a first example treatment device  110 . In this example, the treatment device  110  is an elongate member  112  partially disposed within a tubular member  114 . The elongate member  112  is moveable between a first, unexpanded configuration, as shown in  FIG. 3 , and a second, expanded configuration, as shown in  FIG. 4 . 
     In the illustrated embodiment, the elongate member  112  has a lengthwise axis  113 , a proximal end  120 , a distal end  122 , an adaptor  124 , and a plurality of tubular members  126  attached to the adaptor  124 . The adaptor  124  (e.g., luer fitting) is disposed on the proximal end  120  of the elongate member  112 , has a port  128 , and defines a lumen  130 . The lumen  130  is in fluid communication with the port  128  and a lumen  138  of each tubular member of the plurality of tubular members  126 , as described in more detail herein. 
     Each tubular member of the plurality of tubular members  126  has a proximal end  132 , a distal end  134 , and a main body  136  that defines a lumen  138  and a predefined curve  140 . In the illustrated embodiment, the plurality of tubular members  126  are arranged circumferentially about the lengthwise axis  113 . However, alternative embodiments can include a plurality of tubular members that are positioned in any suitable configuration. Each tubular member of the plurality of tubular members  126  defines the predefined curve  140  when no outside forces are applied on the main body  136 . Each tubular member of the plurality of tubular members  126  is moveable between a substantially straight configuration when the elongate member is in the first, unexpanded configuration, as shown in  FIG. 3 , and a curved configuration when the elongate member is in second, expanded configuration, as shown in  FIG. 4 . The lumen  138  extends from the proximal end  132  to the distal end  134  and is in fluid communication with the lumen  130  defined by the adaptor  124 . In the illustrated embodiment, the plurality of tubular members  126  is formed of a shape memory alloy (e.g., Nitinol) and each tubular member of the plurality of tubular members  126  includes a passive marker  142  on its distal end  134  that allows for visualization of the tubular members  126  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). In an alternative embodiment, a plurality of tubular member can be short relative to the length of the elongate member and be connected at the proximal end to a semi-rigid tube for column strength. 
     The tubular member  114  is disposed over the elongate member  112  and has a proximal end  150 , a distal end  152 , and a main body  154  that defines a lumen  156 . The lumen  156  extends from the proximal end  150  to the distal end  152  and is sized to receive the elongate member  112 . In the illustrated embodiment, the tubular member  114  includes a passive marker  158  on its distal end  152  that allows for visualization of the tubular member  114  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). 
     In the first, unexpanded configuration, the distal end  122  of the elongate member  112  is disposed within the lumen  156  defined by the tubular member  114 . To move the elongate member  112  from the first, unexpanded configuration to the second, expanded configuration a distally-directed force is applied on the elongate member  112  while maintaining the position of the tubular member  114  such that the elongate member  112  is advanced out of the tubular member  114 . Alternatively, the position of the elongate member  112  can be maintained while applying a proximally-directed force on the tubular member  114 , or a distally-directed force can be applied on the elongate member  112  while applying a proximally-directed force on the tubular member  114 . This results in the distal end  122  of the elongate member  112  being advanced out of the tubular member  114  and each tubular member of the plurality of tubular members  126  defining the predefined curve  140 . Force can be applied on the elongate member  112  and/or tubular member  114 , as described above, until a desired amount of the plurality of tubular members  126  is advanced out of the tubular member  114 . Subsequently, a fluid can be passed through the port  128  of the adaptor  124  and through the lumen  138  of each tubular member of the plurality of tubular member  126  to treat tissue. Examples of fluids considered suitable to pass through a tubular member include chemicals, chemotherapeutic agents, cryo-ablatives, ablative therapies, and any other fluid considered suitable for a particular embodiment. The treatment device  110  is considered advantageous at least because it provides a mechanism for injecting a fluid into a larger area of tissue relative to a single needle and because it can be positioned and deployed to a desired diameter within the tissue. 
     Once a desired treatment has been accomplished, the elongate member  112  can be moved from the second, expanded configuration to the first, unexpanded configuration. This can be accomplished by applying a proximally-directed force on the elongate member  112  while maintaining the position of the tubular member  114  such that the elongate member  112  is advanced into the lumen  156  of the tubular member  112 . Alternatively, the position of the elongate member  112  can be maintained while applying a distally-directed force on the tubular member  114 , or a proximally-directed force can be applied on the elongate member  112  while applying a distally-directed force on the tubular member  114 . This results in the distal end  122  of the elongate member  112  being advanced into the lumen  156  of the tubular member  114  and each tubular member of the plurality of tubular members  126  defining a substantially straight configuration within the lumen  156  of the tubular member  114 . Force is applied on the elongate member  112  and/or tubular member  114 , as described above, until a desired amount of the plurality of tubular members  126  is advanced into the lumen  156  of the tubular member  114 . 
       FIGS. 5 and 6  illustrate a second example treatment device  210 . In this example, the treatment device  210  is an elongate member  212  partially disposed within a tubular member  214 . The elongate member  212  is moveable between a first, substantially straight configuration, as shown in  FIG. 5 , and a second, curved configuration, as shown in  FIG. 6 . 
     In the illustrated embodiment, the elongate member  212  has a lengthwise axis  213 , a proximal end  220 , a distal end  222 , a main body  224 , and a cutting member  226 . The main body  224  defines a lumen  228 , a first opening  230 , and a second opening  232 . The lumen  228  extends from the proximal end  220  to the distal end  222 . Each of the first opening  230  and the second opening  232  extends through the main body  224  and is in fluid communication with the lumen  228 . The first opening  230  is disposed between the second opening  232  and the distal end  222  and the second opening  232  is disposed between the first opening  230  and the proximal end  220 . 
     The cutting member  226  has a first end  233 , a second end  234 , a length that extends from the first end  233  to the second end  234 , and a cutting blade  236 . The first end  233  is attached to the distal end  222  of the elongate member  212  within the lumen  226 . The cutting member  226  extends from the first end  233 , through the first opening  230 , along an exterior surface of the elongate member  212 , through the second opening  232  and into the lumen  226 , through the lumen  226  defined by the elongate member  212  to the second end  234 . The cutting blade  236  is disposed between the first and second openings  230 ,  232  defined by the elongate member  212 . The cutting member  226  is moveable between a first position, as shown in  FIG. 5 , and a second position, as shown in  FIG. 6 . The elongate member  212  is in the first, substantially straight configuration when the cutting member  226  is in the first position and the elongate member  212  is in the second, curved configuration when the cutting member  226  is in the second position. In the illustrated embodiment, the elongate member  212  includes a passive marker  242  between its proximal end  220  and its distal end  222  that allows for visualization of the elongate member  212  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). 
     The tubular member  214  is disposed over the elongate member  212  and has a proximal end  250 , a distal end  252 , and a main body  254  that defines a lumen  256 . The lumen  256  extends from the proximal end  250  to the distal end  252  and is sized to receive the elongate member  212 . In the illustrated embodiment, the tubular member  214  includes a passive marker  258  on its distal end  252  that allows for visualization of the tubular member  214  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). 
     The elongate member  212  can be advanced out of the lumen  256  defined by the tubular member  214  by applying a distally-directed force on the elongate member  212  while maintaining the position of the tubular member  214 , applying a distally-directed force on the elongate member  212  while applying a proximally-directed force on the tubular member  214 , or maintaining the position of the elongate member  212  while applying a proximally-directed force on the tubular member  214 . The elongate member  212  can be advanced into the lumen  256  defined by the tubular member  214  by applying a proximally-directed force on the elongate member  212  while maintaining the position of the tubular member  214 , applying a proximally-directed force on the elongate member  212  while applying a distally-directed force on the tubular member  214 , or maintaining the position of the elongate member  212  while applying a distally-directed force on the tubular member  214 . 
     To move the elongate member  212  from the first, substantially straight configuration to the second, curved configuration, tension is applied on the portion of the cutting member  226  that extends from the proximal end  220  of the elongate member  212  (e.g., first end  234 ) in a distal direction while maintaining the position of the elongate member  212  or applying a distally-directed force on the elongate member  212 . Subsequently, torque can be applied on the elongate member  212  such that it rotates relative to tissue being treated and the cutting blade  236  cuts the tissue. Optionally, an elongate member can include a spool with a unidirectional locking gear on the proximal end of the elongate member that can apply tension, maintain tension, or remove tension from a cutting member during use. To move the elongate member  212  from the second, curved configuration to the first, substantially straight configuration, the tension is released from the cutting member  226  while maintaining the position of the elongate member  212  or a proximally-directed force is applied on the elongate member  212 . 
       FIGS. 7 and 8  illustrate a third example treatment device  310 . In this example, the treatment device  310  is an elongate member  312  partially disposed within a tubular member  314 . The elongate member  312  is moveable between a first, unexpanded configuration, as shown in  FIG. 7 , and a second, expanded configuration, as shown in  FIG. 8 . 
     In the illustrated embodiment, the elongate member  312  has a lengthwise axis  313 , a proximal end  320 , a distal end  322 , a main body  324 , and a plurality of cutting members  326  attached to the main body  324 . The main body  324  extends from the proximal end  320  to a location  321  disposed between the proximal end  320  and the distal end  322 . The plurality of cutting members  326  extends from the location  321  disposed between the proximal end  320  and the distal end  322  to the distal end  322 . Optionally, laser cut patterns (e.g., interlocking sections, non-elongating spiral-cut sections) can be introduced into portions of the main body  324  to increase flexibility. 
     Each cutting member of the plurality of cutting members  326  has a proximal end  332 , a distal end  334 , and a main body  336  that defines a predefined curve  338  when free of outside forces. Each cutting member of the plurality of cutting member  326  has a first, substantially straight configuration when disposed within the tubular member  314  and a second, curved configuration when free of the tubular member  314 . In the illustrated embodiment, the plurality of cutting members  326  are arranged circumferentially around the lengthwise axis  313 . However, alternative embodiments can include a plurality of cutting members that are positioned in any suitable configuration. Each cutting member of the plurality of cutting members  326  is moveable between a substantially straight configuration when the elongate member  312  is in the first, unexpanded configuration, as shown in  FIG. 7 , and a curved configuration when the elongate member  312  is in the second, expanded configuration, as shown in  FIG. 8 . In the illustrated embodiment, each cutting member of the plurality of cutting members  326  is formed of a shape memory alloy (e.g., Nitinol, 316 Stainless Steel, MP35N, thermoplastic), the elongate member  312  includes a passive marker  340  on its distal end  322 , and each cutting member of the plurality of cutting members  326  includes a passive marker  342  between the proximal end  332  and the distal end  334 . The markers  340 ,  342  allowing for visualization of the elongate member  212  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). 
     The tubular member  314  is disposed over the elongate member  312  and has a proximal end  350 , a distal end  352 , and a main body  354  that defines a lumen  356 . The lumen  356  extends from the proximal end  350  to the distal end  352  and is sized to receive the elongate member  312 . The tubular member  314  includes a passive marker  358  on its distal end  352  that allows for visualization of the tubular member  314  in a magnetic resonance image and for device conspicuity without obscuring target tissue during treatment (e.g., biopsy, removal). In an alternative embodiment, a wire member disposed through the tubular member  314  and attached to the distal end  334  if the plurality of cutting members  326  can manipulate the shape of the plurality of cutting members  326  by applying and releasing tension on the wire member. For example, applying tension to the wire member can change the shape of the plurality of cutting members from oblong to circular, allowing for different treatment to be performed by the treatment device  310  and changing the volume of tissue sampled or excised by the treatment device. 
     In the first, unexpanded configuration, the distal end  322  of the elongate member  312  is disposed within the lumen  356  defined by the tubular member  314 . To move the elongate member  312  from the first, unexpanded configuration to the second, expanded configuration a distally-directed force is applied on the elongate member  312  while maintaining the position of the tubular member  314  such that the elongate member  312  is advanced out of the tubular member  314 . Alternatively, the position of the elongate member  312  can be maintained while applying a proximally-directed force on the tubular member  314 , or a distally-directed force can be applied on the elongate member  312  while applying a proximally-directed force on the tubular member  314 . This results in the distal end  322  of the elongate member  312  being advanced out of the tubular member  314  and each cutting member of the plurality of cutting members  326  defining the predefined curve  338 . Force can be applied on the elongate member  312  and/or tubular member  314 , as described above, until a desired amount of the plurality of cutting members  326  is advanced out of the tubular member  314 . Subsequently, torque is applied on the elongate member  312  such that it rotates relative to tissue being treated and the plurality of cutting members  326  cuts the tissue. 
     Once a desired treatment has been accomplished, the elongate member  312  can be moved from the second, expanded configuration to the first, unexpanded configuration. This can be accomplished by applying a proximally-directed force on the elongate member  312  while maintaining the position of the tubular member  314  such that the elongate member  312  is advanced into the lumen  356  of the tubular member  314 . Alternatively, the position of the elongate member  312  can be maintained while applying a distally-directed force on the tubular member  314 , or a proximally-directed force can be applied on the elongate member  312  while applying a distally-directed force on the tubular member  314 . This results in the distal end  322  of the elongate member  312  being advanced into the lumen  356  of the tubular member  314  and each cutting member of the plurality of cutting members  326  defining a substantially straight configuration within the lumen  356  of the tubular member  314 . Force can be applied on the elongate member  312  and/or tubular member  314 , as described above, until a desired amount of the plurality of tubular members  326  is advanced into the lumen  356  of the tubular member  314 . 
     An elongate tubular member, elongate member, and a tubular member can be formed of any suitable material and selection of a suitable material to form an elongate tubular member, elongate member, and a tubular member can be based on various considerations, including the intended use of an access device or treatment device of which the member is a component. Examples of MRI compatible materials considered suitable to form an elongate tubular member, elongate member, and/or a tubular member include biocompatible materials, materials that can be made biocompatible, metals, electrically insulating materials, electrically non-conducting materials, non-magnetic materials, shape memory alloys, including nickel-titanium alloys such as Nitinol, stainless steel, including Austenitic stainless steel, stainless steel containing Iron, stainless steel including Inconel, 316 stainless steel, cobalt chromium, cobalt chromium alloys, Inconel, titanium, thermoplastics, polymers, PEEK, carbon-filled PEEK, ceramics, the materials described herein, combinations of the described herein, and any other material considered suitable for a particular embodiment. Examples of markers considered suitable to include in an access device and/or treatment device are described in U.S. Patent Application No. 63/135,801, filed on Jan. 11, 2021, which is hereby incorporated by reference in its entirety for the purpose of describing markers considered suitable to include in an access device and/or treatment device. Any marker included in an access device and/or treatment device can visualized using an image obtained by MRI or identified by a unique pattern recognized and transformed into a virtual instrument within a program and displayed on a screen. 
     Various methods of performing interventional medical treatment under MRI are described herein. While the methods described herein are shown and described as a series of acts, it is to be understood and appreciated that the methods are not limited by the order of acts, as some acts may in accordance with these methods may be omitted, occur in the order shown and/or described, occur in different orders, and/or occur concurrently with other acts described herein. 
       FIGS. 9A and 9B  illustrate a schematic illustration of an example method  400  of performing treatment under MRI. 
     An initial step  402  comprises positioning a patient within a magnetic resonance scanner. Another step  404  comprises scanning a first portion of the patient using the magnetic resonance scanner. Another step  406  comprises obtaining a magnetic resonance image of the first portion of the patient. Another step  408  comprises identifying a tissue that has predefined characteristics using the magnetic resonance image. While the patient remains positioned within the magnetic resonance scanner used to scan a portion of the patient, another step  410  comprises advancing a medical device into a bodily passage and to, within, or adjacent to, the tissue while scanning a second portion of the patient that includes the medical device using the magnetic resonance scanner. Another step  412  comprises obtaining a magnetic resonance image of the second portion of the patient that includes the medical device. Another step  414  comprises confirming the position of the medical device within the bodily passage. Another step  416  comprises advancing a biopsy device through the medical device and to the tissue while scanning a third portion of the patient that includes the biopsy device using the magnetic resonance scanner. Another step  418  comprises obtaining a magnetic resonance image of the third portion of the patient that includes the biopsy device. Another step  420  comprises confirming the position of the biopsy device. Another step  422  comprises collecting a tissue sample from the tissue using the biopsy device while scanning a fourth portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner. Another step  424  comprises obtaining a magnetic resonance image of the fourth portion of the patient that includes the biopsy device. Another step  426  comprises confirming the tissue sample has been collected. Another step  428  comprises withdrawing the biopsy device and the tissue sample through the medical device. Another step  430  comprises determining whether the tissue sample meets a predefined criterion. If the tissue sample does not meet the predefined criterion, additional steps comprise  432  withdrawing the medical device from the bodily passage and  434  removing the patient from the magnetic resonance scanner. If the tissue sample meets the predefined criterion, another step  436  comprises advancing an anchor member through the medical device through which the biopsy device was advanced and to the tissue while the patient remains positioned within the magnetic resonance scanner. Another step  438  comprises securing the anchor member to the tissue to retain the position of the medical device relative to the tissue. Another step  440  comprises advancing an access device over the medical device and toward the tissue. Another step  442  comprises removing the anchor member from the tissue. Another step  444  comprises withdrawing the anchor member from the bodily passage. Another step  446  comprises withdrawing the medical device from the bodily passage. Another step  448  comprises advancing a treatment device through the access device and to the tissue. Another step  450  comprises manipulating the tissue using the treatment device. Another step  452  comprises withdrawing the treatment device from the access device. Another step  454  comprises withdrawing the access device from the bodily passage. 
     Step  402  can be accomplished by positioning a patient within any suitable magnetic resonance scanner, such as conventional magnetic resonance scanners, magnetic resonance scanners that utilize 0.55 T fields, 1.5 T fields, 3 T fields, fields between about 0.055 T and 1.5 T, fields less than 1 T, and any other magnetic resonance scanner considered suitable for a particular embodiment. 
     Step  404  can be accomplished by scanning any suitable portion of a patient and selection of a suitable portion of a patient to scan can be based on various considerations, including the treatment intended to be performed. Examples of portions of a patient considered suitable to scan include the extremities (e.g., arms, legs), chest, breast, spine, neck, head, abdomen, pelvis, prostate, peri-prostatic structures, tissue surrounding the portions described herein, and/or any other portion of the patient considered suitable for a particular embodiment. 
     Step  406  can be accomplished by obtaining the magnetic resonance image from the magnetic resonance scanner used in step  402 . 
     Step  408  can be accomplished by reviewing the magnetic resonance image obtained in step  406  and utilizing conventional techniques and/or methods to determine whether tissue has predefined characteristics (e.g., tissue has characteristics indicative of cancer, is a lesion, abnormal mass). Furthermore, the margins (e.g., borders) of any tissue (e.g., abnormal mass, lesions) can be identified and used in further steps, as described herein, to remove and/or treat the tissue. 
     Step  410  can be accomplished using any suitable medical device, such as the medical devices and/or cannulas described in U.S. Patent Application No. 63/135,801, filed on Jan. 11, 2021, which is hereby incorporated by reference in its entirety for the purpose of describing medical devices considered suitable to complete a step in a method of treatment. Step  410  can be accomplished by applying a distally-directed force on the medical device such that a distal end of the medical device is advanced into a bodily passage and to, within, or adjacent to, the tissue that has been identified as having the predefined characteristics. A bodily passage can include any suitable portion of a body, including existing bodily passages, bodily lumens, and/or bodily passages created through tissues layers and/or fascia using a device described herein. Step  410  can be accomplished by scanning any suitable portion of a patient and selection of a suitable portion of a patient to scan can be based on various considerations, including the location of the tissue that has predefined characteristics. Examples of portions of a patient considered suitable to scan include portions that include the tissue that has predefined characteristics, portions that include the medical device, portions that include the tissue that has predefined characteristics and the medical device, and any other portion of the patient considered suitable for a particular embodiment. For example, a second portion of the patient can be the same as, or different than, the first portion of the patient. 
     Step  412  can be accomplished by obtaining the magnetic resonance image from the magnetic resonance scanner used in step  402 . 
     Step  414  can be accomplished by reviewing the magnetic resonance image obtained in step  412  and confirming the medical device is positioned at a desired location within the bodily passage (e.g., at, within, or adjacent to, the tissue that has been identified as having the predefined characteristics). This can be accomplished by visualizing one or more markers included on the medical device. If the medical device is not positioned at a desired location, an optional step comprises manipulating the position of the medical device. 
     Step  416  can be accomplished by applying a distally-directed force on the biopsy device such that a distal end of the biopsy device is advanced into a lumen defined by the medical device, through the lumen defined by the medical device, and to the tissue that has been identified as having the predefined characteristics. Step  416  can be accomplished by scanning any suitable portion of a patient and selection of a suitable portion of a patient to scan can be based on various considerations, including the location of the tissue that has predefined characteristics. Examples of portions of a patient considered suitable to scan include portions that include the tissue that has predefined characteristics, portions that include the biopsy device, portions that include the tissue that has predefined characteristics and the biopsy device, and any other portion of the patient considered suitable for a particular embodiment. For example, a third portion of the patient can be the same as, or different than, the first portion of the patient and/or the second portion of the patient. 
     Step  416 , step  422 , and step  428  can be accomplished using any suitable biopsy device, such as MRI compatible biopsy devices, the Echotip ProCore provided by Cook Medical, the Echotip Ultra provided by Cook Medical, and any other biopsy device considered suitable for a particular embodiment. Alternatively, step  416 , step  422 , and step  428  can be completed using a biopsy device that is not MRI compatible. This alternative step can comprise advancing the biopsy device through the medical device and to the tissue without scanning a portion of the patient that includes the biopsy device using the magnetic resonance scanner. An alternative to step  422  can comprise collecting a tissue sample using the biopsy device without scanning a portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner. 
     Step  418  can be accomplished by obtaining the magnetic resonance image from the magnetic resonance scanner used in step  402 . 
     Step  420  can be accomplished by reviewing the magnetic resonance image obtained in step  418  and confirming the biopsy device is positioned at a desired location within the bodily passage (e.g., at, within, or adjacent to, the tissue that has been identified as having the predefined characteristics). If the biopsy device is not positioned at a desired location, an optional step comprises manipulating the position of the biopsy device. 
     Step  422  can be accomplished using the biopsy device and conventional methods of obtaining a tissue sample using a biopsy device. Step  422  can be accomplished by scanning any suitable portion of a patient and selection of a suitable portion of a patient to scan can be based on various considerations, including the location of the tissue that has predefined characteristics. Examples of portions of a patient considered suitable to scan include portions that include the tissue that has predefined characteristics, portions that include the biopsy device, portions that include the tissue that has predefined characteristics and the biopsy device, and any other portion of the patient considered suitable for a particular embodiment. For example, a fourth portion of the patient can be the same as, or different than, the first portion of the patient, the second portion of the patient, and/or the third portion of the patient. 
     Step  410 , step  416 , and/or step  422  can optionally be conducted in combination with performing an ultrasound on the portion of the patient that includes the medical device and/or biopsy device. In embodiments in which an ultrasound image is obtained, the magnetic resonance image obtained can be electronically fused with a real-time ultrasound image (e.g., transrectal ultrasound image of a prostate). 
     Step  424  can be accomplished by obtaining the magnetic resonance image from the magnetic resonance scanner used in step  402 . 
     Step  426  can be accomplished by reviewing the magnetic resonance image obtained in step  424  and confirming the biopsy device has collected the tissue sample (e.g., the tissue that has been identified as having the predefined characteristics). If the biopsy device has not collected the tissue sample, optional steps comprise repeating step  416 , step  418 , step  420 , step  422 , step  424 , and/or step  426 . 
     Step  406 , step  412 , step  418 , and/or step  424  can comprise obtaining a single still image. Alternatively, step  404 , step  410 , step  416 , and/or step  422  can be repeated any desired number of times such that step  406 , step  412 , step  418 , and/or step  424  comprises obtaining multiple magnetic resonance images of a portion that can be grouped as a cine to show motion. 
     Step  428  can be accomplished by applying a proximally-directed force on the biopsy device such that it is withdrawn from the lumen defined by the medical device. In an alternative embodiment, step  416 , step  418 , step  420 , step  422 , step  424 , step  426 , and step  428  can be omitted from method  400 , and other methods described herein, and the medical device advanced in step  410  can be utilized to obtain a biopsy and steps similar to those described with respect to a biopsy device can be completed utilizing the medical device. In another alternative embodiment, an anchor can be placed, as described herein, the medical device withdrawn, and the anchor used to track a biopsy device to the tissue. 
     Step  430  can be accomplished using any technique or method considered suitable to determine whether tissue meets predefined criterion. For example, step  430  can utilize conventional techniques and methods for determining whether a tissue sample is malignant, such as frozen section and/or other cytological methods. 
     Each of step  406 , step  408 , step  410 , step  412 , step  414 , step  416 , step  418 , step  420 , step  422 , step  424 , step  426 , step  428 , and/or step  430  can be accomplished without removing the patient from the magnetic resonance scanner within which the patient is positioned in step  402 . 
     Step  432  can be accomplished by applying a proximally-directed force on the medical device until it is withdrawn from the bodily passage. Step  434  can be accomplished by withdrawing the patient from the magnetic resonance scanner such that the patient is free of the magnetic resonance scanner. 
     Step  436  can be accomplished using any suitable anchor member, such as the anchor members described in U.S. Patent Application No. 63/135,801, filed on Jan. 11, 2021, which is hereby incorporated by reference in its entirety for the purpose of describing anchor members considered suitable to complete a step in a method of treatment. Step  436  can be accomplished by applying a distally-directed force on the anchor member such that a distal end of the anchor member is advanced into a lumen defined by the medical device, through the lumen defined by the medical device, and to the tissue, within, or adjacent to the tissue. Optionally, step  436  can be completed while scanning a fifth portion of the patient that includes the anchor member using the magnetic resonance scanner and additional steps that can be completed subsequent to this optional step include obtaining a magnetic resonance image of the fifth portion of the patient that includes the anchor member, and confirming the position of the anchor member. In embodiments in which it is desired to utilize the magnetic resonance scanner on a second patient that is different from the patient, optional steps that can be completed subsequent to step  438  include removing the patient from the magnetic resonance scanner while maintaining the position of the patient on a surface, positioning a second patient within the magnetic resonance scanner, scanning a portion of the second patient using the magnetic resonance scanner, obtaining a magnetic resonance image of the portion of the second patient, removing the second patient from the magnetic resonance scanner, and repositioning the patient within the magnetic resonance scanner. 
     Completion of step  438  of securing the anchor member into the tissue will depend on the structural configuration of the anchor member. Examples of suitable actions that can be performed for this step include, but are not limited to, axially advancing the anchoring member through a lumen defined by a medical device until a portion of the anchor member (e.g., barb) becomes disposed within the tissue, or applying torque on the anchoring member until a portion of the anchor member becomes disposed within the tissue. Alternatively, step  438  can comprise anchoring the anchor member into a second, different tissue disposed adjacent to or within the tissue. Step  438  allows for the medical device and/or anchor to be utilized as a guide rail to a target site such that one or more other devices can be advanced over the medical device and/or anchor to a treatment site. Optionally, step  438  can be completed while scanning a sixth portion of the patient that includes the anchor member using the magnetic resonance scanner and additional steps that can be completed subsequent to this optional step include obtaining a magnetic resonance image of the sixth portion of the patient that includes the anchor member, and confirming the position of the anchor member. Step  438  allows for site retention such that the medical device and/or anchor member stays positioned relative to the tissue after biopsy and prior to treatment and can be used to direct a treatment device to the tissue, as described in more detail herein. 
     Step  440  can be accomplished by applying a distally-directed force on the access device such that a distal end of the access device is advanced over the medical device and to the tissue. Any suitable access device, such as access device  10 , can be used to complete step  440 . Utilization of access device  10  provides a mechanism for dilating a bodily passage subsequent to advancement of the access device  10  to a point of treatment, as described in more detail herein, which can prevent trauma to critical structures by dilating the bodily passage without cutting or tearing. Optionally, step  440  can be completed while scanning a seventh portion of the patient that includes the access device using the magnetic resonance scanner and additional steps that can be completed subsequent to this optional step include obtaining a magnetic resonance image of the seventh portion of the patient that includes the access device, and confirming the position of the access device (e.g., by visualizing the markers disposed on the access device). 
     While an access device has been used in step  440 , an alternative method can substitute the following steps for step  440  to accomplish sequential dilation of a bodily passage: applying a distally-directed force on a first inner sheath such that a distal end of the first inner sheath is advanced over the medical device and to the tissue; applying a distally-directed force on a second inner sheath such that a distal end of the second inner sheath is advanced over the first inner sheath and to the tissue; and applying a distally-directed force on an outer sheath such that a distal end of the outer sheath is advanced over the second inner sheath and to the tissue. 
     Completion of step  442  of removing the anchor member from the tissue will depend on the structural configuration of the anchor member. Examples of suitable actions that can be performed for this step include, but are not limited to, applying a proximally-directed force on the anchor member such that it is withdrawn through the lumen defined by a medical device until a portion of the anchor member (e.g., barb) becomes free of the tissue, applying torque to the anchoring member until the portion of the anchor member disposed within the tissue becomes free of the tissue, or applying a distally-directed force on the anchor member such that it is advanced within the lumen defined by a medical device until a portion of the anchor member (e.g., barb) becomes free of the tissue. Alternatively, step  442  can comprise removing the anchor member from a tissue disposed adjacent to or within the tissue. Optionally, step  442  can be completed while scanning a portion of the patient that includes the anchor member using the magnetic resonance scanner and additional steps that can be completed subsequent to this optional step include obtaining a magnetic resonance image of the portion of the patient that includes the anchor member, and confirming the position of the anchor member. 
     Step  444  can be accomplished by applying a proximally-directed force on the anchor member such that it is withdrawn from the lumen defined by the medical device. In an alternative embodiment, step  436 , step  438 , step  442 , and step  444  can be omitted from method  400  and similar steps can be omitted from other methods described herein. 
     Step  446  can be accomplished by applying a proximally-directed force on the medical device until it is withdrawn from the bodily passage. Optional steps that can be completed in embodiments in which sequential dilation has been accomplished include withdrawing the first inner sheath and withdrawing the second inner sheath. 
     In an alternative embodiment, step  440  can comprise withdrawing the medical device from the bodily passage, step  442  can comprise advancing an access device over the anchor member and toward the tissue, step  444  can comprise removing the anchor member from the tissue, and step  446  can comprise withdrawing the anchor member from the bodily passage. In this alternative embodiment, the access device is advanced over the anchor member rather than the medical device. Sequential dilation can also be accomplished over the anchor member and be completed as described herein. 
     Step  448  can be accomplished by applying a distally-directed force on the treatment device such that a distal end of the treatment device is advanced into a lumen defined by the access device, or in alternative embodiments the outer sheath or dilator, and through the lumen defined by the access device, or in alternative embodiments the outer sheath or dilator, and to the tissue. In embodiments in which the portion of the treatment device that is advanced into the access device has an outside diameter that is greater than the inside diameter of the access device, this step results in dilation of the bodily passage as a result of the access device expanding in response to advancement of the treatment device through the lumen defined by the access device. Any suitable treatment device can be utilized in method  400  and selection of a suitable treatment device can be based on various considerations, such as the intended use of the treatment device. Examples of treatment devices considered suitable to treat tissue for which a tissue sample meets a predefined criterion include treatment device  110 , treatment device  210 , treatment device  310 , dissection tools, optical fibers, optical fibers formed of a material selected from the group consisting of argon, dye, erbium, excimer, Nd:YAG, and CO 2 , optical fibers that include control cables (e.g., ultra-high molecular weight polyethylene, Dyneema) to direct the fibers toward tissue intended to be treated, needles, cannulas, such as those described herein or incorporated by reference, and any other treatment device considered suitable for a particular embodiment. Optionally, step  448  can be completed while scanning a portion of the patient that includes the treatment device using the magnetic resonance scanner and additional steps that can be completed subsequent to this optional step include obtaining a magnetic resonance image of the portion of the patient that includes the treatment device, and confirming the position of the treatment device. 
     Step  450  can be accomplished by physically manipulating the tissue using the treatment device, which can include removing of all or a portion of the tissue, introducing a material into the tissue, applying a treatment to the tissue, and performing any other suitable treatment on the tissue. Examples of treatments considered suitable include laser direct therapy, photodynamic therapy (PDT), chemotherapy, a focal treatment, a radical prostatectomy, infusion of ablative agents, such as acetic acid, ethanol, sclerosants (e.g., sodium tetradecyl sulfate), chemotherapeutic agents, and any other treatment considered suitable for a particular embodiment. Optionally, step  450  can be completed while scanning a portion of the patient that includes the treatment device using the magnetic resonance scanner and additional steps that can be completed subsequent to this optional step include obtaining a magnetic resonance image of the portion of the patient that includes the treatment device, and confirming the position of the treatment device. For example, a magnetic resonance scanner can be utilized to determine areas of tissue that become devitalized during ablative therapies. The heating and devitalization of tissue can be monitored such that it occurs in real time and can be used to guide the targeted treatment of the tissue (e.g., prostate). 
     In embodiments in which treatment device  110  is being utilized to complete step  450 , the following steps can be completed to manipulate the tissue: moving the elongate member from the first, unexpanded configuration to the second, expanded configuration; introducing a fluid through each tubular member of the plurality of tubular members; moving the elongate member from the second, expanded configuration to the first, unexpanded configuration. An optional step comprises confirming placement of the treatment device by visualizing the markers via a magnetic resonance image that can be obtained as described herein. These steps can be accomplished as described herein with respect to treatment device  110 . Use of treatment device  110  provides a mechanism for controlling the advancement of the plurality of tubular members into the tissue and, therefore, the location of the treatment performed. For example, in embodiments in which agents are introduced through the plurality of tubular members, the tissue can be devitalized and the progression of the treatment monitored by MRI (e.g., by scanning the portion of the tissue that includes the treatment device and reviewing the image obtained from the scan). 
     In embodiments in which treatment device  210  is being utilized to complete step  450 , the following steps can be completed to manipulate the tissue: advancing the elongate member out of the lumen defined by the tubular member; applying tension on the cutting member such that elongate member moves from the first, substantially straight configuration to the second, curved configuration; applying torque on the elongate member such that it rotates relative to the tissue and the cutting blade cuts the tissue; releasing tension from cutting member such that the elongate member moves from the second, curved configuration to the first substantially straight configuration; advancing the elongate member into the lumen defined by the tubular member. An optional step comprises confirming placement of the treatment device by visualizing the markers via a magnetic resonance image that can be obtained as described herein. These steps can be accomplished as described herein with respect to treatment device  210 . Use of treatment device  210  provides a mechanism for cutting tissue by rotating the elongate member relative to the tissue as tension is applied to the cutting member and the degree of the curve defined by the elongate member can be manipulated by adjusting the tension applied to the cutting member. 
     In embodiments in which treatment device  310  is being utilized to complete step  450 , the following steps can be completed to manipulate the tissue: moving the elongate member from the first, unexpanded configuration to the second, expanded configuration; applying torque to the elongate member such that it rotates relative to the tissue and the plurality of cutting members cuts the tissue; moving the elongate member from the second, expanded configuration to the first, unexpanded configuration. An optional step comprises confirming placement of the treatment device by visualizing the markers via a magnetic resonance image that can be obtained as described herein. These steps can be accomplished as described herein with respect to treatment device  310 . Use of treatment device  310  provides a mechanism for cutting tissue by rotating the elongate member relative to the tissue and for retrieving the cut tissue using the plurality of cutting members as a retrieval basket. 
     Optionally, step  450  can be repeated. For example, as the space within the body enlarges as step  450  is being completed, more of the treatment device can be introduced into the space created in initial step  450  to increase the area of disruption. Once the space has been maximally enlarged, the treatment device and access device are removed and can then be inserted into different locations of the tissue until the entire tissue that has predefined characteristics is removed. 
     Step  452  can be accomplished by applying a proximally-directed force on the treatment device until it is withdrawn from the lumen defined by the access device, or in alternative embodiments, the outer sheath or dilator. 
     Optional steps that can be completed prior, or subsequent, to step  450  or step  452  include applying suction to the access device or treatment device; introducing a flushing fluid through access device or treatment device; introducing a second treatment device (e.g., basket, grasper) through access device and to tissue; manipulating the tissue (e.g., removing, macerating, disrupting using laser, electrosurgical, thermal, or other disruption or ablative methods) using second treatment device; and withdrawing second treatment device. 
     Step  454  can be accomplished by applying a proximally-directed force on the access device, or in alternative embodiments the outer sheath or dilator, until it is withdrawn from the bodily passage. 
       FIGS. 10A and 10B  illustrate another schematic illustration of an example method  500  of performing treatment under MRI. 
     An initial step  502  comprises positioning a patient within a magnetic resonance scanner. Another step  504  comprises scanning a first portion of the patient using the magnetic resonance scanner. Another step  506  comprises obtaining a magnetic resonance image of the first portion of the patient. Another step  508  comprises identifying a tissue that has predefined characteristics using the magnetic resonance image. While the patient remains positioned within the magnetic resonance scanner used to scan a portion of the patient, another step  510  comprises advancing a medical device into a bodily passage and to, within, or adjacent to, the tissue while scanning a second portion of the patient that includes the medical device using the magnetic resonance scanner. Another step  512  comprises obtaining a magnetic resonance image of the second portion of the patient that includes the medical device. Another step  514  comprises confirming the position of the medical device within the bodily passage. Another step  516  comprises advancing an anchor member through the medical device and to the tissue while the patient remains positioned within the magnetic resonance scanner. Another step  518  comprises securing the anchor member to the tissue to retain the position of the anchor member relative to the tissue. Another step  520  comprises withdrawing the medical device from the bodily passage. Another step  522  comprises advancing an access device over the anchor member and toward the tissue. Another step  524  comprises removing the anchor member from the tissue. Another step  526  comprises withdrawing the anchor member from the bodily passage. Another step  528  comprises advancing a biopsy device through the access device and to the tissue while scanning a third portion of the patient that includes the biopsy device using the magnetic resonance scanner. Another step  530  comprises obtaining a magnetic resonance image of the third portion of the patient that includes the biopsy device. Another step  532  comprises confirming the position of the biopsy device. Another step  534  comprises collecting a tissue sample from the tissue using the biopsy device while scanning a fourth portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner. Another step  536  comprises obtaining a magnetic resonance image of the fourth portion of the patient that includes the biopsy device. Another step  538  comprises confirming the tissue sample has been collected. Another step  540  comprises withdrawing the biopsy device and the tissue sample through the access device. Another step  542  comprises determining whether the tissue sample meets a predefined criterion. If the tissue sample does not meet the predefined criterion, additional steps comprise  544  withdrawing the outer sheath from the bodily passage and  546  removing the patient from the magnetic resonance scanner. If the tissue sample meets the predefined criterion, another step  548  comprises advancing a treatment device through the access device and to the tissue. Another step  550  comprises manipulating the tissue using the treatment device. Another step  552  comprises withdrawing the treatment device from the access device. Another step  554  comprises withdrawing the access device from the bodily passage. Another step  556  comprises removing the patient from the magnetic resonance scanner. 
       FIGS. 11A and 11B  illustrate another schematic illustration of an example method  600  of performing treatment on a prostate under MRI. 
     An initial step  602  comprises positioning a patient within a magnetic resonance scanner. Another step  604  comprises scanning a prostate and surrounding tissue of the patient using the magnetic resonance scanner. Another step  606  comprises obtaining a magnetic resonance image of the prostate and surrounding tissue of the patient. Another step  608  comprises identifying a tissue within the magnetic resonance image that has predefined characteristics. While the patient remains positioned within the magnetic resonance scanner used to scan the prostate and surrounding tissue, another step  610  comprises advancing a medical device into a bodily passage and to the tissue while scanning a first portion of the patient that includes the medical device using the magnetic resonance scanner. Another step  612  comprises obtaining a magnetic resonance image of the second portion of the patient that includes the medical device. Another step  614  comprises confirming the position of the medical device within the bodily passage. Another step  616  comprises advancing a biopsy device through the medical device and to the tissue while scanning a third portion of the patient that includes the biopsy device using the magnetic resonance scanner. Another step  618  comprises obtaining a magnetic resonance image of the third portion of the patient that includes the biopsy device. Another step  620  comprises confirming the position of the biopsy device. Another step  622  comprises collecting a tissue sample from the tissue using the biopsy device while scanning a fourth portion of the patient that includes the biopsy device and the tissue using the magnetic resonance scanner. Another step  624  comprises obtaining a magnetic resonance image of the fourth portion of the patient that includes the biopsy device. Another step  626  comprises confirming the tissue sample has been collected. Another step  628  comprises withdrawing the biopsy device and the tissue sample through the medical device. Another step  630  comprises determining whether the tissue sample meets a predefined criterion. If the tissue sample does not meet the predefined criterion, additional steps comprise  632  withdrawing the medical device from the bodily passage and  634  removing the patient from the magnetic resonance scanner. If the tissue sample meets the predefined criterion, another step  636  comprises advancing an anchor member through the medical device through which the biopsy device was advanced and to the tissue while the patient remains positioned within the magnetic resonance scanner. Another step  638  comprises securing the anchor member to the tissue to retain the position of the medical device relative to the tissue. Another step  640  comprises advancing an access device over the medical device and toward the tissue. Another step  642  comprises removing the anchor member from the tissue. Another step  644  comprises withdrawing the anchor member from the bodily passage. Another step  646  comprises withdrawing the medical device from the bodily passage. Another step  648  comprises advancing a treatment device through the access device and to the tissue. Another step  650  comprises manipulating the tissue using the treatment device. Another step  652  comprises withdrawing the treatment device from the access device. Another step  654  comprises withdrawing the access device from the bodily passage. 
     Method  400 , method  500 , and method  600  are considered advantageous at least because each step of method  400 , method  500 , and method  600  can be performed during a single patient visit and using the same magnetic resonance scanner, which increases efficiency and reduces the number of patient visits and procedures performed. This results in a set of procedures in which a physician can visualize, diagnose, and treat a patient in a single patient visit. Furthermore, these methods are considered advantageous at least because they provide methods for removing abnormal tissue (e.g., tumor). For example, MR offers high spatial and temporal resolution in real time that can image tissue (e.g., prostate) and assess it both from a functional aspect as well as morphologically. The methods described herein provide for non-invasive abnormal tissue (e.g., tumor) detection, staging, and consequent direction of biopsy and interventional therapies. They can be used to guide physicians to the desired treatment strategies for an individual patient since the imaging quality of MRI is superior as compared to ultrasound. The higher resolution procedures described herein lead to a better outcome for the patient, faster recovery time, less perioperative pain, and less blood loss as compared to open surgical techniques allowing a patient to return to normal activity in a shorter period of time. While some steps have been described as being completed while scanning a portion of the patient using a magnetic resonance scanner and other steps have not been described as being performed while scanning a portion of the patient using a magnetic resonance scanner, any step described herein can be completed while scanning a portion of a patient using the magnetic resonance scanner, and/or an ultrasound device or without scanning a portion of a patient using a magnetic resonance scanner. In embodiments in which an ultrasound image is obtained, the magnetic resonance image obtained can be electronically fused with a real-time ultrasound image (e.g., transrectal ultrasound image of a prostate). While some steps have been described as being completed while scanning a portion of the patient using a magnetic resonance scanner, this step can be broken into two separate steps such that a subsequent step of scanning a portion of a patient using the magnetic resonance scanner can be accomplished. Furthermore, any step which is completed while scanning a portion of the patient using the magnetic resonance scanner can comprise obtaining a single still image and be repeated any desired number of times to obtain multiple magnetic resonance images that can be grouped as a cine to show motion and/or any step which is completed while scanning a portion of the patient using the magnetic resonance scanner can comprise obtaining a live image, such as being completed under live real-time MRI visualization. 
     Optionally, any step described herein can include concurrently completing magnetic resonance thermometry (MRT) such that noninvasive temperature monitoring using temperature sensitive magnetic resonance (MR) parameters can be accomplished. Alternatively, an optional step, or steps, that can be included in any method described herein can include completing magnetic resonance thermometry (MRT). These optional steps provide a mechanism for monitoring thermal therapies during intraoperative MRI or monitoring temperature near implanted medical device and/or intraoperative devices. In addition, these optional steps provide a mechanism for monitoring a thermal dose during therapy (e.g., monitoring the application of thermally active ablative technologies), monitoring any potential damage from therapy delivery and/or any unintended RF-inducing heating of a device used for the intraoperative MRI procedure, and real-time monitoring of thermal changes within tissue such that feedback control of a thermal dose being delivered to tissue can be completed. Any MRT scanning protocols can be interleaved with any thermal therapy to avoid RF noise or magnetic field perturbations that would negatively impact MR imaging. A thermal therapy can interface with the MRI scanner for automatic thermal dosing based on near real-time MRT.  FIG. 12  illustrates an MRT-PRF temperature contour around a copper wire.  FIG. 13  illustrates a MRT-PRF temperature contour around a Zilver brand stent.  FIG. 14  illustrates a gradient echo pulse sequence used for MRT based on PRF shift method. 
     While a number of methods have been described herein, it will be appreciated that the method may be a non-invasive method that does not require an invasive intervention by a medical professional. For example, a method may be carried out within a body lumen or passageway, such as the ear canal or a nasal passage, for example in order to place a device within such a passageway. Equally, methods may be implemented on a cadaver or artificial body parts for example for training purposes. Moreover, the skilled person will appreciate that the methods described herein may not be used on the human or animal body at all, but may be used in order to view other types of devices using MRI imaging techniques, for example in an industrial setting. 
       FIG. 15  illustrates an exemplary kit  700  comprising an access device  702  according to an embodiment, such as access device  10  illustrated in  FIGS. 1 and 2 ; a first treatment device  704  according to an embodiment, such as treatment device  110  illustrated in  FIGS. 3 and 4 ; a second treatment device  706  according to an embodiment, such as treatment device  210  illustrated in  FIGS. 5 and 6 ; a third treatment device  708  according to an embodiment, such as treatment device  310  illustrated in  FIGS. 7 and 8 ; and instructions for use  710 . 
     While kit  700  has been illustrated as including one access device  702  and three treatment devices  704 ,  706 , and  708 , any suitable number, and type, of access devices and/or treatment devices can be included in a kit. Selection of a suitable number of access devices and/or treatment devices to include in a kit according to a particular embodiment can be based on various considerations, such as the treatment intended to be performed. Examples of numbers of access devices and/or treatment devices considered suitable to include in a kit include at least one, one, two, a plurality, three, four, five, six, seven, eight, nine, ten, more than ten, and any other number considered suitable for a particular embodiment. 
     Furthermore, while access device  10 , treatment device  110 , treatment device  210 , and treatment device  310 , have been illustrated as included in kit  700 , any suitable access device and/or treatment device can be included in a kit. Selection of a suitable access device and/or treatment device to include in a kit according to a particular embodiment can be based on various considerations, such as the treatment intended to be performed. Examples of access devices and treatment devices considered suitable to include in a kit include access device  10 , treatment device  110 , treatment device  210 , treatment device  310 , and/or any other access device and/or treatment device considered suitable for a particular embodiment. 
     Those with ordinary skill in the art will appreciate that various modifications and alternatives for the described and illustrated examples can be developed in light of the overall teachings of the disclosure, and that the various elements and features of one example described and illustrated herein can be combined with various elements and features of another example without departing from the scope of the invention. Accordingly, the particular arrangement of elements and steps disclosed herein have been selected by the inventor(s) simply to describe and illustrate examples of the invention and are not intended to limit the scope of the invention or its protection, which is to be given the full breadth of the appended claims and any and all equivalents thereof.