Patent Publication Number: US-2020289789-A1

Title: Steerable medical device and method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of and claims the benefit of priority under 35 U.S.C. § 120 to Scheibe et al., U.S. patent application Ser. No. 15/917,953, filed on Mar. 12, 2018, entitled “STEERABLE MEDICAL DEVICE AND METHOD,” which claims the benefit of priority to U.S. Provisional Application Ser. No. 62/471,003, filed on Mar. 14, 2017, entitled “CATHETER STEERING HANDLE,” each of which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     The present invention relates to a steerable device, and more specifically relates to a medical device that is steerable in multiple directions. 
     In various medical procedures, steerable catheters or other devices can allow for navigation to a location within a patient and/or articulation within the patient in order to access the location and/or achieve a particular orientation or series of orientations within the patient. In many cases, such devices include limited degrees of motion, making it difficult to achieve particular orientations and or locations. In turn, such devices make some medical procedures more difficult than the medical procedures would otherwise be with a device having more degrees of motion. 
     OVERVIEW 
     This overview is intended to provide an overview of subject matter of the present patent document. It is not intended to provide an exclusive or exhaustive explanation of the invention. The detailed description is included to provide further information about the present patent document. 
     The present inventors have recognized, among other things, that the subject matter can be used with respect to a medical device with multidirectional steering capability. In various examples, the present subject matter can be used with a device, an apparatus, a system, and/or a method to provide for increased maneuverability within a patient. The present inventors have recognized that the present subject matter can be used to provide a catheter or other medical device with multiple degrees of motion to allow for a tip of the device having a 360-degree range of deflection. To better illustrate the apparatuses, systems, and methods described herein, a non-limiting list of examples is provided here: 
     Example 1 can include subject matter that can include a steerable medical device including a handle including a longitudinal axis. An elongate shaft extends distally from the handle. The elongate shaft includes a distal tip and a lumen through the elongate shaft. At least four pullwires are disposed within the handle and extend to and are anchored proximate the distal tip of the elongate shaft. The at least four pullwires include a first pullwire, a second pullwire, a third pullwire, and a fourth pullwire. At least two actuators are associated with the handle. The at least two actuators include a first actuator and a second actuator. The at least two actuators are operably coupled to the at least four pullwires. Actuation of the first actuator in a first actuator direction causes tension in the first pullwire and deflection of the distal tip in a first tip direction. Actuation of the first actuator in a second actuator direction causes tension in the second pullwire and deflection of the distal tip in a second tip direction substantially opposite the first tip direction. Actuation of the second actuator in a first actuator direction causes tension in the third pullwire and deflection of the distal tip in a third tip direction different from the first tip direction and the second tip direction. Actuation of the second actuator in a second actuator direction causes tension in the fourth pullwire and deflection of the distal tip in a fourth tip direction substantially opposite the third tip direction. 
     In Example 2, the subject matter of Example 1 is optionally configured such that the at least four pullwires extend within the elongate shaft to proximate the distal tip of the elongate shaft. 
     In Example 3, the subject matter of any one of Examples 1-2 is optionally configured such that the first actuator is rotatable about the longitudinal axis of the handle. 
     In Example 4, the subject matter of any one of Examples 1-3 is optionally configured such that the second actuator is rotatable about the longitudinal axis of the handle. 
     In Example 5, the subject matter of any one of Examples 1-4 is optionally configured such that the first actuator and the second actuator are each independently rotatable about the longitudinal axis of the handle. 
     In Example 6, the subject matter of any one of Examples 1-5 optionally includes a first threaded member disposed within the handle and movable with actuation of the first actuator. The first threaded member is operably coupled to the first and second pullwires, wherein movement of the first threaded member causes tension in at least one of the first pullwire and the second pullwire. 
     In Example 7, the subject matter of Example 6 is optionally configured such that actuation of the first actuator causes rotation of the first threaded member. 
     In Example 8, the subject matter of Example 7 optionally includes a first drive nut theadably coupled to the first threaded member. The first and second pullwires are operably coupled to the first drive nut, wherein rotation of the first threaded member causes translation of the first drive nut along the longitudinal axis of the handle and, in turn, tension in at least one of the first pullwire and the second pullwire. 
     In Example 9, the subject matter of Example 8 is optionally configured such that proximal translation of the first drive nut causes tension in the first pullwire and distal translation of the first drive nut causes tension in the second pullwire. 
     In Example 10, the subject matter of Example 9 optionally includes a first U-shaped member configured to change a direction of the second pullwire. The second pullwire extends proximally from the first drive nut to the first U-shaped member, around the first U-shaped member, and distally from the first U-shaped member to proximate the distal tip of the elongate shaft. 
     In Example 11, the subject matter of any one of Examples 6-10 optionally includes a second threaded member disposed within the handle and movable with actuation of the second actuator. The second threaded member is operably coupled to the third and fourth pullwires, wherein movement of the second threaded member causes tension in at least one of the third pullwire and the fourth pullwire. 
     In Example 12, the subject matter of Example 11 is optionally configured such that actuation of the second actuator causes rotation of the second threaded member. 
     In Example 13, the subject matter of Example 12 optionally includes a second drive nut theadably coupled to the second threaded member. The third and fourth pullwires are operably coupled to second drive nut, wherein rotation of the second threaded member causes translation of the second drive nut along the longitudinal axis of the handle and, in turn, tension in at least one of the third pullwire and the fourth pullwire. 
     In Example 14, the subject matter of Example 13 is optionally configured such that proximal translation of the second drive nut causes tension in the third pullwire and distal translation of the second drive nut causes tension in the fourth pullwire. 
     In Example 15, the subject matter of Example 14 optionally includes a second U-shaped member configured to change a direction of the fourth pullwire. The fourth pullwire extends proximally from the second drive nut to the second U-shaped member, around the second U-shaped member, and distally from the second U-shaped member to proximate the distal tip of the elongate shaft. 
     In Example 16, the subject matter of any one of Examples 11-15 is optionally configured such that the first threaded member at least partially overlaps the second threaded member. The second threaded member is disposed at least partially within the first threaded member. 
     Example 17 can include, or can optionally be combined with any one of Examples 1-16 to include subject matter that can include a steerable medical device including a handle including a longitudinal axis. An elongate shaft extends distally from the handle. The elongate shaft includes a distal tip and a lumen through the elongate shaft. At least four pullwires are disposed within the handle and extend to and are anchored proximate the distal tip of the elongate shaft. The at least four pullwires include a first pullwire, a second pullwire, a third pullwire, and a fourth pullwire. At least two actuators are associated with the handle. The at least two actuators include a first actuator and a second actuator. At least two threaded members are disposed within the handle. The at least two threaded members include a first threaded member and a second threaded member. The first threaded member is movable with actuation of the first actuator, and the second threaded member is movable with actuation of the second actuator. At least two drive nuts are disposed within the handle. The at least two drive nuts include a first drive nut and a second drive nut. The first drive nut is theadably coupled to the first threaded member and translatable along the longitudinal axis of the handle with movement of the first threaded member. The second drive nut is theadably coupled to the second threaded member and translatable along the longitudinal axis of the handle with movement of the second threaded member. The first and second pullwires are operably coupled to the first drive nut, and the third and fourth pullwires are operably coupled to the second drive nut. Actuation of the first actuator in a first actuator direction causes tension in the first pullwire and deflection of the distal tip in a first tip direction. Actuation of the first actuator in a second actuator direction causes tension in the second pullwire and deflection of the distal tip in a second tip direction substantially opposite the first tip direction. Actuation of the second actuator in a first actuator direction causes tension in the third pullwire and deflection of the distal tip in a third tip direction different from the first tip direction and the second tip direction. Actuation of the second actuator in a second actuator direction causes tension in the fourth pullwire and deflection of the distal tip in a fourth tip direction substantially opposite the third tip direction. 
     In Example 18, the subject matter of Example 17 is optionally configured such that proximal translation of the first drive nut causes tension in the first pullwire and distal translation of the first drive nut causes tension in the second pullwire. Proximal translation of the second drive nut causes tension in the third pullwire and distal translation of the second drive nut causes tension in the fourth pullwire. 
     In Example 19, the subject matter of any one of Examples 17-18 is optionally configured such that the first threaded member at least partially overlaps the second threaded member. The second threaded member is disposed at least partially within the first threaded member. 
     In Example 20, the subject matter of any one of Examples 17-19 is optionally configured such that the first actuator and the second actuator are each independently rotatable about the longitudinal axis of the handle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a steerable medical device in accordance with at least one example of the invention. 
         FIG. 2  is a side view of the steerable medical device of  FIG. 1 . 
         FIG. 3  is a proximally-facing perspective view of a handle of the steerable medical device of  FIG. 1 , the handle having part of a handle housing removed. 
         FIG. 4  is a distally-facing perspective view of the handle of  FIG. 3 , the handle having part of the handle housing removed. 
         FIG. 5  is a side elevational view of the handle of  FIG. 3 , the handle having part of the handle housing removed. 
         FIG. 6  is a side elevational view of the handle of  FIG. 3 , the handle having part of the handle housing and some internal components of the handle removed. 
         FIG. 7  is a perspective cross-sectional view of the handle of  FIG. 3 . 
         FIG. 8  is an exploded perspective view of a distal end the handle of  FIG. 3 . 
         FIG. 9  is an exploded perspective view of a distal end the handle of  FIG. 3 . 
         FIG. 10  is a perspective view of a pullwire connection ring of the steerable medical device of  FIG. 1 . 
         FIG. 11  is a perspective view of movement of a tip of the steerable medical device of  FIG. 1  with actuation of a one control in one direction. 
         FIG. 12  is a perspective view of movement of the tip of the steerable medical device of  FIG. 1  with actuation of a one control in both directions. 
         FIG. 13  is a perspective view of movement of the tip of the steerable medical device of  FIG. 1  with actuation of both controls in both directions. 
     
    
    
     DETAILED DESCRIPTION 
     The present patent application relates to a device, an apparatus, a system, and a method for providing multidirectional steering capability. In various examples, as described herein, the device, apparatus, system, and method can include multiple degrees of motion to allow for increased maneuverability within a patient. The present inventors have recognized that, in some examples, the present subject matter can be used to provide a device with multiple degrees of motion to allow for a tip of the device having a 360-degree range of deflection. In some examples, the device can include a medical device, such as, but not limited to a catheter, a sheath, an introducer, a guidewire, or the like. 
     In various medical procedures, it can be desirable to have a medical device that includes a tip that can articulate in multiple directions, such as, for instance, a 360-degree range of deflection. Medical procedures for which such a device would be helpful include, but are not limited to, an intravascular ultrasound (IVUS) procedure. In some examples, a catheter handle mechanism configured to articulate four individual pullwires can be used to achieve this range of motion. Additionally, in some examples, such a medical device can be used with one hand to steer the distal end of the medical device. In various examples, such a handle mechanism can be used in any steerable/deflectable catheter, therapy device, or other medical device. 
     The following co-owned applications relate to steerable medical devices and are hereby incorporated by reference in their entireties: U.S. application Ser. No. 12/463,570, now U.S. Pat. No. 8,308,659, filed May 11, 2009 and entitled “BI-DIRECTIONAL SHEATH DEFLECTION MECHANISM”; and U.S. application Ser. No. 13/269,858, now U.S. Pat. No. 9,149,607, filed Oct. 10, 2011 and entitled “BI-DIRECTIONAL CATHETER STEERING HANDLE.” 
     Referring now to  FIGS. 1 and 2 , in some examples, a steerable medical device  100  is configured to provide multiple degrees of motion to facilitate navigation and/or articulation of the steerable medical device  100  within a patient. For instance, in some examples, the steerable medical device  100  includes a 360-degree range of deflection. In some examples, the steerable medical device  100  includes a handle  104  including a longitudinal axis  105 . In some examples, the handle  104  includes two handle portions  104 A,  104 B that are coupled together to enclose at least a portion of a handle mechanism  140  (described in greater detail below) within the handle  104 . Although shown and described herein as halving two portions  104 A,  104 B, in other examples, the handle  104  can include fewer or more than two portions, provided the handle mechanism  140  is able to be placed within the handle  104 . In some examples, the handle portions  104 A,  104 B can be coupled together in various ways, including, but not limited to, the handle portions  104 A,  104 B being configured to be snap fit or otherwise frictionally engaged together; the handle portions  104 A,  104 B being welded (ultrasonic, vibration, laser, or the like) together; the handle portions  104 A,  104 B being adhered together using an adhesive (epoxy, silicone, polyurethane, or the like); or a combination thereof. In some examples, the handle portions  104 A,  104 B are shaped and sized to allow for at least a portion of the handle mechanism  140  to be housed within an interior  104 C of the handle  104  with the handle portions  104 A,  104 B coupled together. 
     In some examples, the steerable medical device  100  includes an elongate shaft  108  extending distally from the handle  104 . The elongate shaft, in some examples, includes a distal tip  108 A and a lumen  108 B (see  FIG. 7 ) through the elongate shaft  108 . In some examples, the elongate shaft  108  extends from a distal end of the handle  104 . In some examples, at least a portion of the elongate shaft  108  is disposed within the handle  104 . In further examples, the elongate shaft  108  extends from a valve member  112  disposed at a proximal end of the handle  104 , through the handle  104 , and out of the distal end of the handle  104 . The elongate shaft  108 , in some examples, can include an over-molded hub on a proximal end of the elongate shaft  108  with keying ribs that secure the hub and, in turn, the elongate shaft  108  within the handle  104 . 
     The valve member  112 , in some examples, includes a valve housing  112 A engageable with the handle  104 , for instance, within the proximal end of the housing  104 . The valve member  112 , in some examples, includes a valve cap  112 B disposed at a proximal end of the valve housing  112 A and capturing a valve  112 C between the valve cap  112 B and the valve housing  112 A. The valve  112 C, in some examples, is configured to limit expelling of fluid (for instance, a bodily fluid, a fluid introduced for the procedure, or a combination of the two) to allow insertion of an introducible device (such as, for instance, a guidewire, a catheter, a delivery device, a sensing device, an ablation device, or another medical device) into the steerable medical device  100 . In some examples, it is contemplated that the valve member  112  need not include a valve  112 C, for instance, when fluid being expelled from the device  100  is not an issue. In this way, in some examples, the valve member  112  allows insertion of the introducible device into the steerable medical device  100  and through the elongate shaft  108  to a location within a patient. In some examples, the valve member  112  can include a sideport  112 D in the valve housing  112 A. The sideport  112 D, in some examples, allows for a tube  113  and/or stopcock  114  to fluidly couple to the valve member  112  to allow for introduction of a fluid (such as, but not limited to, saline, water, air, and/or nitrogen) or connection to a suction device, for stance, to remove a bodily fluid from within the patient and/or the steerable medical device  100 . In other examples, the valve member  112  need not include a sideport if introduction and/or removal of one or more fluids is not necessary for the steerable medical device  100 . 
     In some examples, the elongate shaft  108  extends through a nose member  116  disposed at the distal end of the handle  104 . The nose member  116 , in some examples, provides strain relief for the elongate shaft  108 . In some examples, the nose member  116  is substantially conically shaped, although this is not intended to be limiting. As such, in various examples, other shapes of the nose member  116  are contemplated herein. 
     In some examples, a support tube  120  is disposed within the handle  104 . In some examples, the support tube  120  includes a lumen  121  through the support tube  120  sized and shaped to accept a portion of the elongate shaft  108  therein. The support tube  120 , in some examples, is formed from a rigid material such as, but not limited to, plastic, metal, or the like. In some examples, the support tube  120  includes one or more windows  120 C formed in the support tube  120 . In some examples, the support tube  120  includes four windows  120 C. In further examples, the support tube  120  includes four windows  120 C formed in the support tube  120  and equidistantly spaced from one another around a circumference of the support tube  120 . 
     In some examples, the support tube  120  includes a proximal notch  120 A formed in a proximal end of the support tube  120  and a distal notch  120 B formed in a distal end of the support tube  120 . In some examples, the proximal notch  120 A is configured to accept a key  122 A of a proximal insert  122  when the proximal end of the support tube  120  is placed within an opening  122 B of the proximal insert  122 . In this way, interaction between the proximal notch  120 A of the support tube  120  and the key  122 A of the proximal insert  122  inhibits rotation of the support tube  120  relative to the proximal insert  122 . The proximal insert  122 , in some examples, is configured to engage with the handle  104  to inhibit rotation of the proximal insert  122  relative to the handle  104 . In some examples, the distal notch  120 B is configured to accept a key  124 A of a distal support  124  when the distal end of the support tube  120  is placed within an opening  124 B of the distal support  122 . In this way, interaction between the distal notch  120 B of the support tube  120  and the key  124 A of the distal support  124  inhibits rotation of the support tube  120  relative the distal support  124 . In this way, in some examples, each of the handle  104 , the support tube  120 , the proximal insert  122 , and the distal support  124  are engaged with one another and inhibited from rotating with respect to one another. In some examples, the nose member  116  is configured to engage with the distal support  124 . In some examples, the nose member  116  is configured to snap onto the distal support  124 . 
     In some examples, the support tube  120  provides central support to the handle  104  and the handle mechanism  140 . In some examples, the support tube  120  allows components of the handle mechanism  140  to rotate about an outer diameter of the support tube  120  while inhibiting the nose member  116  from rotating. 
     In some examples, at least two actuators  128 ,  132  are associated with the handle  104 . In some examples, the at least two actuators  128 ,  132  include a first actuator  128  and a second actuator  132 . In other examples, the at least two actuators  128 ,  132  include more than two actuators to allow for increased control of the device  100  or aspects of the device  100  if desirable for the particular application of the device  100 . In some examples, at least one of the two actuators  128 ,  132  is rotatable about the longitudinal axis  105  of the handle  104 . That is, in some examples, the first and second actuators  128 ,  132  include knobs that are rotatable with respect to the handle  104  about the longitudinal axis  105  to control the device  100  (for instance, to control deflection of the distal tip  108 A of the elongate shaft  108  of the device  100 ). While the first and second actuators  128 ,  132  are shown as knobs herein, in other examples, it is contemplated that the first and second actuators  128 ,  132  include a slider, a toggle switch, a knob rotatable about an axis other than the longitudinal axis  105 , or a combination of two different types of actuators, provided the first and second actuators  128 ,  132  are capable of controlling the device  100  to perform the particular function of the device  100 . In some examples, the first actuator  128  and the second actuator  132  are each independently rotatable about the longitudinal axis  105  of the handle  104 . That is, rotation of one of the first and second actuators  128 ,  132  does not cause rotation of the other of the first and second actuators  128 ,  132 , thereby allowing independent control of each of the first and second actuators  128 ,  132  by the physician or other user. 
     Referring to  FIGS. 1-7 , at least four pullwires  167 ,  169 ,  187 ,  189 , in some examples, are disposed within the handle  104  and extend to and are anchored proximate the distal tip  108 A of the elongate shaft  108 . In some examples, the at least four pullwires  167 ,  169 ,  187 ,  189  include a first pullwire  167 , a second pullwire  169 , a third pullwire  187 , and a fourth pullwire  189 . In some examples, the at least four pullwires  167 ,  169 ,  187 ,  189  extend within the elongate shaft  108  to proximate the distal tip  108 A of the elongate shaft  108 . In some examples, the at least four pullwires  167 ,  169 ,  187 ,  189  are operably coupled to the first and second actuators  128 ,  132 , such that actuation of the first actuator  128  and/or the second actuator  132  causes tension in at least one of the at least four pullwires  167 ,  169 ,  187 ,  189 , thereby causing the distal tip  108 A of the elongate shaft  108  to deflect, as will be described in more detail below. In some examples, the handle mechanism  140  is configured to cause deflection of the distal tip  108 A of the elongate shaft  108  with actuation of the first actuator  128  and/or the second actuator  132 . 
     In some examples, the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  extend out from the elongate shaft  108  within the handle  104  in order to operably couple with the first and second actuators  128 ,  132 . Because, in some examples, the support tube  120  is disposed over the elongate shaft  108 , the support tube  120  can include one or more windows  120 C formed in a sidewall of the support tube  120  at one or more locations around the support tube  120  to allow for the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  to extend out from the elongate shaft  108  and the support tube  120  to the handle mechanism  140  in order to operably couple the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  to the first and second actuators  128 ,  132 . In some examples, the support tube  120  includes four windows  120 C disposed around the support tube  120 , such that each of the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  exits through its own window  120 C in the support tube  120 . In other examples, the support tube  120  can include fewer than four windows  120 C, such that one or more of the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  share at least one of the windows  120 C. 
     In some examples, the handle mechanism  140  includes a first threaded member  154  disposed within the handle  104  and movable with actuation of the first actuator  128 . In some examples, the first threaded member  154  includes at least one thread  154 A disposed in an outer surface of the first threaded member  154 . The first threaded member  154 , in some examples, is operably coupled to the first and second pullwires  167 ,  169 , such that movement of the first threaded member  154  causes tension in at least one of the first pullwire  167  and the second pullwire  169 . In some examples, rotation of the first actuator  128  causes rotation of the first threaded member  154 . In some examples, the first actuator  128  is coupled directly to the first threaded member  154 . In some examples, the first actuator  128  is coupled to a first drive ring  150 , and the first drive ring  150  is coupled to the first threaded member  154 . The first actuator  128 , in some examples, includes a notch  128 A that is complementarily sized and shaped to accept a key  150 A of the first drive ring  150 , such that, with the first drive ring  150  disposed within an opening of the first actuator  128 , the key  150 A interacts with the notch  128 A to inhibit relative rotation between the first actuator  128  and the first drive ring  150 . In some examples, the first drive ring  150  can be similarly coupled with a keyed configuration to the first threaded member  154  to inhibit relative rotation between the first drive ring  150  and the first threaded member  154 . In this way, in some examples, rotation of the first actuator  128  can cause rotation of the first threaded member  154 . 
     In some examples, the handle mechanism  140  includes a first drive nut  158  theadably coupled to the first threaded member  154 . In some examples, the first drive nut  158  includes a substantially semi-tubular shape configured to partially wrap around the first threaded member  154  with at least one thread  158 B disposed on an inside surface of the first drive nut  158  and sized and shaped to threadably engage with the at least one thread  154 A of the first threaded member  154 . In some examples, the first drive nut  158  is constrained from rotating when threadably coupled to the first threaded member  154  and disposed in place within the interior  104 C of the handle  104 . In further examples, the handle  104  includes a ridge  104 D or other interior surface feature configured to abut or otherwise interact with the first drive nut  158  to inhibit the first drive nut  158  from rotating within the handle  104 . In this way, in some examples, rotation of the first threaded member  154  (for instance, via rotation or other actuation of the first actuator  128 ) causes translation of the first drive nut  158  along the longitudinal axis  105  of the handle  104  as the at least one thread  154 A rotates and, through interaction with the at least one thread  158 B of the first drive nut  158 , imparts translational motion to the first drive nut  158  within the handle  104 . 
     In some examples, the first and second pullwires  167 ,  169  are operably coupled to first drive nut  158 , such that, with rotation of the first threaded member  154 , the first drive nut  158  translates along the longitudinal axis  105  of the handle  104  and, in turn, causes tension in at least one of the first pullwire  167  and the second pullwire  169 . For instance, in some examples, the first and second pullwires  167 ,  169  are coupled to first and second pullwire blocks  166 ,  168 , respectively. In some examples, ends of the first and second pullwires  167 ,  169  are respectively coupled to the first and second pullwire blocks  166 ,  168 . In some examples, the first and second pullwire blocks  166 ,  168  are disposed within the interior  104 C of the handle  104  and on opposite sides of an abutment  158 A of the first drive nut  158 . In some examples, the first pullwire block  166  is disposed on a proximal side of the abutment  158 A with the first pullwire  167  extending distally from the first pullwire block  166 , and the second pullwire block  168  is disposed on a distal side of the abutment  158 A with the second pullwire  169  extending proximally from the second pullwire block  168 . In this way, in some examples, proximal translation of the first drive nut  158  along the longitudinal axis  105  of the handle  104  causes the abutment  158 A of the first drive nut  158  to abut and push the first pullwire block  166  in a proximal direction, thereby causing tension in the first pullwire  167 . Additionally, in some examples, distal translation of the first drive nut  158  along the longitudinal axis  105  of the handle  104  causes the abutment  158 A of the first drive nut  158  to abut and push the second pullwire block  168  in a distal direction, thereby causing tension in the second pullwire  169 . The first pullwire  167 , in some examples, runs directly from the elongate shaft  108  through a first through hole in the abutment  158 A of the first drive nut  158  from the distal side of the abutment  158 A. The first pullwire block  166  can then be threaded over and tightened down onto the first pullwire  167  on the proximal side of the abutment  158 A of the first drive nut  158 , allowing the first pullwire  167  to be tensioned when the first drive nut  158  is translated proximally along the longitudinal axis  105  of the handle  104  while remaining without load when the first drive nut  158  is translated distally along the longitudinal axis  105  of the handle  104 . 
     Because the second pullwire  169  ultimately extends distally down the elongate shaft  108  to proximate the distal tip  108 A of the elongate shaft  108 , in some examples, the second pullwire  169 , which initially extends proximally from the second pullwire block  168 , needs to change direction. To that end, in some examples, a change of direction member can be used to route the second pullwire  169  from a proximally extending direction to a distally extending direction. In various examples, the change of direction member can take various forms, including, but not limited to, a pulley; a substantially U-shaped channel, member, or other such structure; a pin, a rod, or another similar structure; a substantially U-shaped tube; or the like. In some examples, a first U-shaped member  162  is configured to change a direction of the second pullwire  169 , such that the second pullwire  169  initially extends proximally from the second pullwire block  168  and/or the first drive nut  158  to the first U-shaped member  162 . From there, the second pullwire  169  extends around the first U-shaped member  162  and then distally from the first U-shaped member  162  to proximate the distal tip  108 A of the elongate shaft  108 . In this way, by translating the first drive nut  158  proximally within the handle  104  along the longitudinal axis  105 , the first pullwire  167  can be put under tension, and, by translating the first drive nut  158  distally within the handle  104  along the longitudinal axis  105 , the second pullwire  169  can be put under tension. In some examples, the first U-shaped member  162  is formed from a tube, such as, but not limited to, a hypotube, that is formed into substantially a U-shape. The second pullwire  169 , in some examples, extends proximally from the second pullwire block  168 , through a lumen of the first U-shaped member  162 , and then distally from the first U-shaped member  162  through the elongate shaft  108  to proximate the distal tip  108 A of the elongate shaft  108 . In some examples, once the second pullwire  169  exits the elongate shaft  108 , the second pullwire  169  is routed through the first U-shaped member  162  (for instance, a curved hypotube). In some examples, a composite tubing jacket can be used to shield the second pullwire  169  within the first U-shaped member  162 . In some examples, the composite tubing jacket can include a lubricious inner surface to reduce friction on the second pullwire  169 . In some examples, the second pullwire  169  can include a braid reinforcement to maintain durability and wear resistance. The second pullwire  169 , in some examples, then runs through a second through hole on the proximal face of the abutment  158 A of the first drive nut  158 . On the distal side of the second through hole, in some examples, the second pullwire block  168  can be threaded over the second pullwire  169  and tightened onto the second pullwire  169 , thereby locking the second pullwire  169  in place. Such a configuration, in some examples, allows the second pullwire  169  to be tensioned when the first drive nut  158  is translated distally along the longitudinal axis  105  of the handle  104  while remaining without load when the first drive nut  158  is translated proximally along the longitudinal axis  105  of the handle  104 . 
     In some examples, the handle mechanism  140  includes a second threaded member  174  disposed within the handle  104  and movable with actuation of the second actuator  132 . In some examples, the second threaded member  174  includes at least one thread  174 A disposed in an outer surface of the second threaded member  174 . The second threaded member  174 , in some examples, is operably coupled to the third and fourth pullwires  187 ,  189 , such that movement of the second threaded member  174  causes tension in at least one of the third pullwire  187  and the fourth pullwire  189 . In some examples, rotation of the second actuator  132  causes rotation of the second threaded member  174 . In some examples, the second actuator  132  is coupled directly to the second threaded member  174 . In some examples, the second actuator  132  is coupled to a second drive ring  170 , and the second drive ring  170  is coupled to the second threaded member  174 . The second actuator  132 , in some examples, includes a notch  132 A that is complementarily sized and shaped to accept a key  170 A of the second drive ring  170 , such that, with the second drive ring  170  disposed within an opening of the second actuator  132 , the key  170 A interacts with the notch  132 A to inhibit relative rotation between the second actuator  132  and the second drive ring  170 . In some examples, the second drive ring  170  can be similarly coupled with a keyed configuration to the second threaded member  174  to inhibit relative rotation between the second drive ring  170  and the second threaded member  174 . In this way, in some examples, rotation of the second actuator  132  can cause rotation of the second threaded member  174 . In some examples, the second drive wheel  170  is attached to a distal lock  126 , which, in turn, is coupled to the distal support  124 . In this way, in some examples, the distal lock  126  allows rotation of the second actuator  132 , the distal lock  126  and the second drive ring  170  around the distal support  124  but inhibits distal or proximal movement of the second actuator  132 , the distal lock  126  and the second drive ring  170  relative the handle  104  and the first actuator  128 . In some examples, the distal lock  126  includes a first distal lock portion  126 A and a second distal lock portion  126 B that are engageable together to form the distal lock  126 , for instance, to facilitate assembly of the handle mechanism  140 . 
     In some examples, the handle mechanism  140  includes a second drive nut  178  theadably coupled to the second threaded member  174 . In some examples, the second drive nut  178  includes a substantially semi-tubular shape configured to partially wrap around the second threaded member  174  with at least one thread  178 B disposed on an inside surface of the second drive nut  178  and sized and shaped to threadably engage with the at least one thread  174 A of the second threaded member  174 . In some examples, the second drive nut  178  is constrained from rotating when threadably coupled to the second threaded member  174  and disposed in place within the interior  104 C of the handle  104 . In further examples, one or more catches  179  or other structures are included within the handle  104  and configured to abut or otherwise interact with the second drive nut  178  to inhibit the second drive nut  178  from rotating within the handle  104 . In some examples, the second drive nut  178  abuts two catches  179  to constrain the second drive nut  178  from rotating within the handle  104 . In this way, in some examples, rotation of the second threaded member  174  (for instance, via rotation or other actuation of the second actuator  132 ) causes translation of the second drive nut  178  along the longitudinal axis  105  of the handle  104  as the at least one thread  174 A rotates and, through interaction with the at least one thread  178 B of the second drive nut  178 , imparts translational motion to the first drive nut  178  within the handle  104 . 
     In some examples, the third and fourth pullwires  187 ,  189  are operably coupled to second drive nut  178 , such that, with rotation of the second threaded member  174 , the second drive nut  178  translates along the longitudinal axis  105  of the handle  104  and, in turn, causes tension in at least one of the third pullwire  187  and the fourth pullwire  189 . For instance, in some examples, the third and fourth pullwires  187 ,  189  are coupled to third and fourth pullwire blocks  186 ,  188 , respectively. In some examples, ends of the third and fourth pullwires  187 ,  189  are respectively coupled to the third and fourth pullwire blocks  186 ,  188 . In some examples, the third and fourth pullwire blocks  186 ,  188  are disposed within the interior  104 C of the handle  104  and on opposite sides of an abutment  178 A of the second drive nut  178 . In some examples, the third pullwire block  186  is disposed on a proximal side of the abutment  178 A with the third pullwire  187  extending distally from the third pullwire block  186 , and the fourth pullwire block  188  is disposed on a distal side of the abutment  178 A with the fourth pullwire  189  extending proximally from the fourth pullwire block  188 . In this way, in some examples, proximal translation of the second drive nut  178  along the longitudinal axis  105  of the handle  104  causes the abutment  178 A of the second drive nut  178  to abut and push the third pullwire block  186  in a proximal direction, thereby causing tension in the third pullwire  187 . Additionally, in some examples, distal translation of the second drive nut  178  along the longitudinal axis  105  of the handle  104  causes the abutment  178 A of the second drive nut  178  to abut and push the fourth pullwire block  188  in a distal direction, thereby causing tension in the fourth pullwire  189 . The third pullwire  187 , in some examples, runs directly from the elongate shaft  108  through a first through hole in the abutment  178 A of the second drive nut  178  from the distal side of the abutment  178 A. The third pullwire block  186  can then be threaded over and tightened down onto the third pullwire  187  on the proximal side of the abutment  178 A of the second drive nut  178 , allowing the third pullwire  187  to be tensioned when the second drive nut  178  is translated proximally along the longitudinal axis  105  of the handle  104  while remaining without load when the second drive nut  178  is translated distally along the longitudinal axis  105  of the handle  104 . 
     Because the fourth pullwire  189  ultimately extends distally down the elongate shaft  108  to proximate the distal tip  108 A of the elongate shaft  108 , in some examples, the fourth pullwire  189 , which initially extends proximally from the fourth pullwire block  188 , needs to change direction. To that end, in some examples, a change of direction member can be used to route the fourth pullwire  189  from a proximally extending direction to a distally extending direction. In various examples, the change of direction member can take various forms, including, but not limited to, a pulley; a substantially U-shaped channel, member, or other such structure; a pin, a rod, or another similar structure; a substantially U-shaped tube; or the like. In some examples, a second U-shaped member  182  is configured to change a direction of the fourth pullwire  189 , such that the fourth pullwire  189  initially extends proximally from the fourth pullwire block  188  and/or the second drive nut  178  to the second U-shaped member  182 . From there, the fourth pullwire  189  extends around the second U-shaped member  182  and then distally from the second U-shaped member  182  to proximate the distal tip  108 A of the elongate shaft  108 . In this way, by translating the second drive nut  178  proximally within the handle  104  along the longitudinal axis  105 , the third pullwire  187  can be put under tension, and, by translating the second drive nut  178  distally within the handle  104  along the longitudinal axis  105 , the fourth pullwire  189  can be put under tension. In some examples, the second U-shaped member  182  is formed from a tube, such as, but not limited to, a hypotube, that is formed into substantially a U-shape. The fourth pullwire  189 , in some examples, extends proximally from the fourth pullwire block  188 , through a lumen of the second U-shaped member  182 , and then distally from the second U-shaped member  182  through the elongate shaft  108  to proximate the distal tip  108 A of the elongate shaft  108 . 
     In some examples, once the fourth pullwire  189  exits the elongate shaft  108 , the fourth pullwire  189  is routed through the second U-shaped member  182  (for instance, a curved hypotube). In some examples, a composite tubing jacket can be used to shield the fourth pullwire  189  within the second U-shaped member  182 . In some examples, the composite tubing jacket can include a lubricious inner surface to reduce friction on the fourth pullwire  189 . In some examples, the fourth pullwire  189  can include a braid reinforcement to maintain durability and wear resistance. The fourth pullwire  189 , in some examples, then runs through a second through hole on the proximal face of the abutment  178 A of the second drive nut  178 . On the distal side of the second through hole, in some examples, the fourth pullwire block  188  can be threaded over the fourth pullwire  189  and tightened onto the fourth pullwire  189 , thereby locking the fourth pullwire  189  in place. Such a configuration, in some examples, allows the fourth pullwire  189  to be tensioned when the second drive nut  178  is translated distally along the longitudinal axis  105  of the handle  104  while remaining without load when the second drive nut  178  is translated proximally along the longitudinal axis  105  of the handle  104 . 
     In some examples, the first threaded member  154  at least partially overlaps the second threaded member  174 , such that the second threaded member  174  is disposed at least partially within the first threaded member  154 . In this way, in some examples, use of space within the interior  104  can be substantially optimized in order to keep an overall size of the handle  104  relatively small and manageable by the physician or other user. In some examples, the second threaded member  174  rotates around the support tube  120  with actuation of the second actuator  132 . The first threaded member  154 , in some examples, rotates around the second threaded member  174  and/or the second drive nut  178  with actuation of the first actuator  128 . In this way, in some examples, multidirectional control of the distal tip  108 A can be achieved, and the relatively numerous components of the handle mechanism  140  to achieve such multidirectional control can be fit within the confines of the interior  104 C of the handle  104 , while keeping the size of the handle  104  relatively manageable by the physician or other user, without interference between various components of the handle mechanism  140 . 
     Referring to  FIG. 10 , the pullwire ring  109 , in some examples, can be disposed proximate the distal tip  108 A of the elongate shaft  108 . In various examples, the pullwire ring  109  can be adhered to, molded into, welded to, or otherwise attached to the elongate shaft  108  proximate the distal tip  108 A of the elongate shaft  108 . In some examples, the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  are attached to the pullwire ring  109 . In various examples, the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  can be attached to the pullwire ring  109  by welding, soldering, brazing adhesive, mechanical fastener, or a combination thereof. In some examples, the first, second, third, and fourth pullwires  167 ,  169 ,  187 ,  189  are equidistantly spaced around the pullwire ring  109  from one another. In some examples, the first and second pullwires  167 ,  169  are spaced around the pullwire ring  109  substantially 180 degrees from one another. In some examples, the third and fourth pullwires  187 ,  189  are spaced around the pullwire ring  109  substantially 180 degrees from one another. 
     Referring now to  FIGS. 11-13 , various examples of deflection of the distal tip  108 A of the elongate shaft  108  are shown. Through actuation of one or both of the first and second actuators  128 ,  132 , various positions of the distal tip  108 A of the elongate shaft  108  can be achieved. For instance, in some examples, actuation of the first actuator  128  in a first actuator direction causes tension in the first pullwire  167  and deflection of the distal tip  108 A in a first tip direction A. In further examples, actuation of the first actuator  128  in a second actuator direction causes tension in the second pullwire  169  and deflection of the distal tip  108 A in a second tip direction B substantially opposite the first tip direction A. In some examples, rotation of the first actuator  128  in a first rotational direction (for instance, counterclockwise) causes tension in the first pullwire  167  to deflect the distal tip  108 A in the first tip direction A, and rotation of the first actuator  128  in a second rotational direction (for instance, clockwise) causes tension in the second pullwire  169  to deflect the distal tip  108 A in the second tip direction B. In further examples, actuation of the second actuator  132  in a first actuator direction causes tension in the third pullwire  187  and deflection of the distal tip  108 A in a third tip direction C different from the first tip direction A and the second tip direction B. In still further examples, actuation of the second actuator  132  in a second actuator direction causes tension in the fourth pullwire  189  and deflection of the distal tip  108 A in a fourth tip direction D substantially opposite the third tip direction C. In some examples, rotation of the second actuator  132  in a first rotational direction (for instance, counterclockwise) causes tension in the third pullwire  187  to deflect the distal tip  108 A in the third tip direction C, and rotation of the second actuator  132  in a second rotational direction (for instance, clockwise) causes tension in the fourth pullwire  189  to deflect the distal tip  108 A in the fourth tip direction D. Referring specifically to  FIG. 13 , in some examples, by actuating each of the first and second actuators  128 ,  132 , the elongate shaft  108  can be deflected in various ways and a plurality of positions of the distal tip  108 A can be achieved. As demonstrated in  FIG. 13 , substantially any position of the distal tip  108 A can be achieved within a spherical area at the distal end of the elongate shaft  108 A. In this way, such maneuverability can facilitate navigation of the distal tip  108 A and/or the elongate shaft  108  within the patient and, once in place within the patient, articulation of the distal tip  108 A in substantially any direction to facilitate any of various procedures intended to be performed by the device  100  or with assistance from the device  100 . 
     Referring back to  FIG. 2 , the placement of the first and second actuators  128 ,  132 , in some examples, allows for one-handed operation by the physician or other user. That is, having both the first actuator  128  and the second actuator  132  at the distal end of the handle  104 , the physician or other user can hold onto the handle  104  with one hand and use a thumb and/or a finger (for instance, the index finger) to control each of the first and second actuators  128 ,  132 . One-handed control of the device  100  is advantageous in that it frees up the other hand of the physician or other user to do other things and/or control other devices during the procedure for which the device  100  is being used. Moreover, each of the first and second actuators  128 ,  132  can be actuated independently without interfering with the actuation of the other of the first and second actuators  128 ,  132 . This is achieved, in some examples, by constraining each of the first and second actuators  128 ,  132  from translating during rotation of the first and second actuators  128 ,  132 , as described herein. Additionally, actuation of the various components of the handle mechanism  140  associated with the first actuator  128  can be accomplished without impacting actuation of the various components of the handle mechanism  140  associated with the second actuator  132  and vice versa. For instance, translating the first drive nut  158  does not affect translating the second drive nut  178  and vice versa. In this way, independent control of the first and second actuators  128 ,  132  can be achieved. 
     In some examples, the four pullwires  167 ,  169 ,  187 ,  189  can be tensioned at different rates using the first and second actuators  128 ,  132  to provide distal tip  108 A deflection in substantially 360 degrees. Additionally, in some examples, the handle mechanism  140  enables substantially 360-degree steering of the elongate shaft  108  of the device by using only two sliding components (the first and second drive nuts  158 ,  178 ) within the handle  104 . Having only two sliding members can allow for more/easier control over the location of the pullwire blocks  166 ,  168 ,  186 ,  188  which can impact the amount of “dead zone” when at least one of the first and second actuators is rotated (the amount of rotation in which neither pullwire associated with that actuator is engaged). Minimizing such “dead zone” can be advantageous. 
     In some examples, by using two U-shaped members  162 ,  182  (for instance, two curved hypotube segments), two pullwires  169 ,  189  of the four pullwires  167 ,  169 ,  187 ,  189  are redirected substantially 180 degrees, which reverses the direction of the pull required to activate these two wires  169 ,  189 . This allows each of the two independent sliding components (the first and second drive nuts  158 ,  178 ) to each be used on a pair of pullwires (pullwires  167 ,  169  for the first drive nut  158  and pullwires  187 ,  189  for the second drive nut  178 ). Each sliding component  158 ,  178  is independently mated to the respective actuator  128 ,  132 . In this way, the distal tip  108 A can achieve a full range of deflection/steering through a coordinated rotation of each of the first and second actuators  128 ,  132 . 
     The present inventors have recognized various advantages of the subject matter described herein. For instance, in some examples, the examples of devices, apparatuses, systems, and methods described herein can be used to provide multidirectional steering capability. In some examples, the subject matter described herein can provide multiple degrees of motion to a medical device to allow for increased maneuverability within a patient. In various examples, the device, apparatus, system, and method can be used to provide a device with multiple degrees of motion to allow for a tip of the device to have a 360-degree range of deflection. Such a device is further advantageous, in some examples, since such a range of deflection can be achieved using one hand to steer the distal end of the medical device, thereby freeing the other hand for other things, such as controlling another device used in the procedure. While various advantages of the example apparatuses are listed herein, this list is not considered to be complete, as further advantages may become apparent from the description and figures presented herein. 
     Although the subject matter of the present patent application has been described with reference to various examples, workers skilled in the art will recognize that changes can be made in form and detail without departing from the scope of the subject matter recited in the below claims. 
     The above Detailed Description includes references to the accompanying drawings, which form a part of the Detailed Description. The drawings show, by way of illustration, specific examples in which the present apparatuses and methods can be practiced. These embodiments are also referred to herein as “examples.” 
     The above Detailed Description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more elements thereof) can be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. Also, various features or elements can be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter can lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. 
     In this document, the terms “a” or “an” are used to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “about” and “approximately” or similar are used to refer to an amount that is nearly, almost, or in the vicinity of being equal to a stated amount. 
     In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, an apparatus or method that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. 
     The Abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.