MARKING DEVICE WITH RETRACTABLE CANNULA
An actuator for a marking device includes a cannula mount, a stylet mount, and a trigger. The cannula mount is configured to slidably support a cannula. The cannula mount includes an elongated cannula support shaft. The stylet mount is configured to slidably support a stylet. The stylet mount includes an elongated stylet support shaft. The trigger is rotatably mounted to a trigger mount of a handle. The actuator is mounted to the handle to effect movement of a stylet and a cannula to eject an imaging marker from the marking device and to retract the cannula into the handle following the ejection of the imaging marker from the marking device
The invention relates generally to a device for implanting an imaging marker in a tissue mass and particularly to a marking device having a cannula that retracts into a handle following implantation of the imaging marker in the tissue mass.
DESCRIPTION OF THE RELATED ARTSubcutaneous imaging markers are commonly implanted in humans to identify a particular location in various areas and organs of the body. For example, markers are positioned at biopsy sites so that a practitioner can readily identify the tissue sample location after the biopsy procedure is completed. Markers are also used to denote the locations of lesions for therapeutic procedures, such as chemotherapy. Typically, markers located within the body can be viewed by various imaging techniques, such as radiography, ultrasound, and magnetic resonance imaging (MRI).
Various devices and methods have been developed for implanting a marker at a predetermined site in a tissue mass. One method of implanting a marker involves inserting a probe into the tissue mass and, with guidance from imaging systems, placing the tip of the probe near a predetermined location. Once the probe is in place and the biopsy is executed, a device comprising a flexible cannula, a stylet slidably mounted in the cannula, and the imaging marker positioned in the cannula distally of the stylet is manually threaded through the probe and positioned with the tip of the cannula at the predetermined location. Thereafter, the stylet is advanced distally to eject the imaging marker from the cannula at the predetermined location, and the cannula and the stylet are removed from the probe.
Other marking devices are self-contained in that they do not require a pre-inserted probe to guide the device to the predetermined location. Rather, such self-contained devices typically comprise a handle that supports a rigid cannula with a sharpened tip and a stylet mounted in the cannula. The imaging marker is positioned in the cannula distally of the stylet. In operation, the cannula is inserted into the body, and its sharpened, distal tip is placed at the predetermined location using imaging systems for guidance. The imaging marker can be implanted in one of two ways: the stylet advances distally to eject the marker from the cannula, or the cannula retracts relative to the stationary stylet to expose the marker to the predetermined location. Following implantation, the handle is pulled proximally to remove the cannula and the stylet from the body. The practitioner must be careful when pulling the marking device from the body because the sharpened tip of the cannula, which has been in contact with the patient's blood, is exposed and can potentially stab the practitioner, other persons assisting with the marking procedure, or even the patient if the practitioner accidentally moves the marking device towards the patient after removal of the marking device from the body. Thus, it is desirable for a self-contained marking device to comprise a cannula that retracts entirely into the handle following implantation of the imaging marker at the predetermined location.
SUMMARY OF THE INVENTIONA marking device according to one embodiment of the invention comprises a handle having a handle proximal end and a handle distal end and defining a hollow interior, a cannula having a cannula distal end and slidably mounted to the handle for slidable movement between an extended position where the cannula distal end extends beyond the handle distal end and a retracted position where the cannula distal end is received within the hollow interior, a stylet having a stylet distal end and slidably mounted to the handle for slidable movement between a ready position where the stylet distal end is proximal of the cannula distal end to form a marker recess in the cannula between the cannula distal end and the stylet distal end and an implant position where the stylet distal end extends into at least the marker recess, an imaging marker located within the marker recess, and an actuator operably coupled to the stylet and the cannula to effect movement of the stylet from the ready position to the implant position to eject the marker from the marker recess and movement of the cannula from the extended position to the retracted position.
The movement of the cannula from the extended position to the retracted position can occur after the movement of the stylet from the ready position to the implant position.
The stylet distal end can extend to at least the cannula distal end when in the implant position. The stylet distal end can extend beyond the cannula distal end when in the implant position.
The actuator can be configured to effect movement of the stylet from the implant position to a withdrawn position where the stylet is retracted into the hollow interior of the handle. The actuator can be configured to effect movement of the stylet from the implant position to the withdrawn position when effecting movement of the cannula from the extended position to the retracted position. The stylet distal end can be received within the hollow interior of the handle when in the withdrawn position.
The actuator can manually move the stylet from the ready position to the implant position. The actuator can automatically move the cannula from the extended position to the retracted position. The actuator can automatically effect movement of the stylet from the implant position to a withdrawn position where the stylet is retracted into the hollow interior of the handle when automatically moving the cannula from the extended position to the retracted position. The stylet distal end can be received within the hollow interior of the handle when in the withdrawn position.
The actuator can comprise a cannula biasing element operably coupled with the cannula in the handle to bias the cannula to the retracted position. The actuator can further comprise a trigger mounted to the handle and operable between a locked position where the trigger prevents movement of the cannula to the retracted position by the biasing element and a cannula release position where the trigger does not prevent movement of the cannula to the retracted position by the biasing element. The actuator can further comprise a cannula mount that supports a proximal end of the cannula for sliding movement in the hollow interior and operably couples the biasing element with the cannula. The actuator can further comprise a stylet mount that supports a proximal end of the stylet in the hollow interior. The actuator can further comprise a stylet biasing element operably coupled with the stylet mount in the hollow interior to bias the stylet to the ready position. The cannula mount can be operably coupled with the stylet mount so that the cannula mount directs the stylet mount proximally in the hollow interior to move the stylet to a withdrawn position where the stylet is retracted into the hollow interior when the cannula moves to the retracted position. The trigger can comprise a cam surface that rides along the stylet mount as the trigger moves from the locked position to the cannula release position to displace the stylet mount and move the stylet to the implant position. The cam surface can ride off the stylet mount as the trigger reaches the stylet advance position to the cannula release position to effect proximal movement of the stylet mount and the cannula mount.
The cannula distal end can comprise at least one imageable marking. The cannula can be rigid. The cannula can terminate at a sharpened tip at the cannula distal end. Alternatively, the cannula can be flexible.
A marking device according to another embodiment of the invention comprises a handle having a handle proximal end and a handle distal end and defining a hollow interior, a cannula having a cannula distal end and slidably mounted to the handle for slidable movement between an extended position where the cannula distal end extends beyond the handle distal end and a retracted position where the cannula distal end is received within the hollow interior, a stylet having a stylet distal end located in the cannula proximal of the cannula distal end to form a marker recess in the cannula between the cannula distal end and the stylet distal end, an imaging marker located within the marker recess, and an actuator operably coupled to the cannula to effect movement of the cannula from the extended position to the retracted position to expose the marker.
The stylet can be slidably mounted to the handle for slidable movement to a withdrawn position where the stylet is retracted into the hollow interior. The stylet distal end can be received within the hollow interior of the handle when in the withdrawn position. The stylet can be operably coupled to cannula so that the stylet moves to the withdrawn position when the cannula moves to the retracted position. Movement of the stylet to the withdrawn position can be delayed until the cannula distal end is at least at the stylet distal end to eliminate the marker recess.
The actuator can comprise a cannula biasing element operably coupled with the cannula in the handle to bias the cannula to the retracted position. The stylet can be operably coupled with the cannula so that movement of the cannula to the retracted position by the biasing element moves the stylet with the cannula to a withdrawn position where the stylet is retracted into the hollow interior.
The cannula distal end can comprise at least one imageable marking.
A method according to one embodiment of the invention of implanting an imaging marker into a tissue mass with a marking device comprising a handle defining a hollow interior, a cannula having a cannula distal end and slidably mounted to the handle, a stylet having a stylet distal end located in the cannula proximal of the cannula distal end to form a marker recess in the cannula between the cannula distal end and the stylet distal end, and an imaging marker located within the marker recess comprises implanting the imaging marker from the marker recess into the tissue mass, and retracting the cannula entirely into the handle.
The retracting of the cannula entirely into the handle can comprise retracting the cannula distal end into the hollow interior. The retracting of the cannula entirely into the handle can comprise automatically retracting the cannula entirely into the handle. The method can further comprise retracting the stylet with the cannula. The method can further comprise positioning the cannula distal end in the tissue mass with an imaging system.
The method can further comprise retracting the stylet into the handle. The retracting of the stylet into the handle can occur during the retracting of the cannula entirely into the handle. The retraction of the stylet can be delayed until the cannula distal end is retracted to at least at the stylet distal end to eliminate the marker recess. The implanting of the imaging marker can occur during the retracting of the cannula to expose the imaging marker to the tissue mass. Alternatively, the implanting of the imaging marker can comprise extending the stylet at least into the marker recess to expel the imaging marker from the marker recess. The extending of the stylet at least into the marker recess can comprise manually extending the stylet at least into the marker recess.
In the drawings:
Referring now to the figures,
As best seen in
Together, the distal section 30 and the proximal section 34 have an inner surface 60 that defines a generally cylindrical hollow interior 62. As best seen in
Referring again to
The actuator 20 comprises a cannula mount 90 and a stylet mount 92 that slidably support the cannula 16 and the stylet 18, respectively, in the handle 14. As shown in
The stylet mount 92, as shown in
Referring back to
In addition to the cannula mount 90, the stylet mount 92, and the trigger 150, the actuator 20 comprises a pair of biasing members: a cannula mount biasing member 170 and a stylet mount biasing member 172. According to the illustrated embodiment of the invention, the biasing members 170, 172 are compression springs. Preferably, the cannula mount biasing member 170 tapers from a distal end 174 to a proximal end 176.
The cannula 16 is generally hollow and comprises a distal end 180 defining a tip 182 and a proximal end 184 mounted to the cannula support shaft 94 of the cannula mount 92. The cannula 16 is preferably sufficiently rigid to permit the direct insertion of the cannula 16 into a tissue mass. Alternatively, the cannula 16 can be flexible for use with a probe or the like. The tip 182 is preferably pointed for insertion through skin and into the tissue mass; however, the tip 182 can optionally be blunt, for example, if the marking apparatus 10 is utilized with a probe or the like. Further, the distal end 180 of the cannula 16 can be beveled, as best seen in
When the marking device 10 is in an assembled condition, as shown in
As best seen in
The trigger 150 is movable from the locked position shown in
Continuing rotation of the trigger 150 beyond the stylet advance position to a cannula release position shown in
In operation, a practitioner grasps the marking device 10 at the hand rest area 56 and inserts the cannula tip 182 through the skin of patient's body into a tissue mass 196. An exemplary tissue mass 196 is a breast, as shown in
A marking device 210 according to another embodiment of the invention for implanting an imaging marker 212 at a predetermined location in a tissue mass is illustrated in
The handle 214 of the marking device 210 is similar to the handle 14 of the first embodiment marking device 10 and comprises a distal section 230 that terminates in an open distal end 232 and an integral proximal section 234 that terminates at a closed proximal end 236. A trigger mount 238 in the distal section 230 comprises a pivot mount 240 for mounting a portion of the actuator 220, as will be described in more detail below. Together, the distal section 230 and the proximal section 234 have an inner surface 242 that defines a generally cylindrical hollow interior 244. The handle 214 comprises a pair of stops 245 extending radially inward from the inner surface 242 in the hollow interior 244. The handle 214 further includes a proximal stop 268 projecting into the hollow interior 244 from the proximal end 236. The hollow interior 244 is closed at the distal end 232 of the handle 214 by a handle cap 246. The handle cap 246 comprises a generally hollow frustoconical body 248 with a distal endwall 250 from which extends a nose 252 sized to slidably receive the cannula 216. For convenience of this description, the handle cap 246 is described as being separate from the handle 214. However, the handle cap 246 can be considered as part of the handle 214 and can even be integrated with the handle 214.
The actuator 220 comprises a cannula mount 260 and a stylet mount 262 that slidably support the cannula 216 and the stylet 218, respectively, in the handle 214. The cannula mount 260 includes an elongated cannula support shaft 264 integral with a generally orthogonal annular body 266 with a peripheral wall 274 having a trigger detent 272 formed therein. A pair of legs 269 having a sloped terminal cam surface 270 extends proximally from the annular body 266. The stylet mount 262 comprises an elongated stylet support shaft 276 integral with a generally orthogonal body 278 having a pair of diametrically opposed resilient arms 280 extending distally from the body 278 on opposite sides of the stylet support shaft 276. Each arm 280 comprises a proximal sloped stop surface 282 near the body 278 and terminates at an inclined cam follower surface 284.
With continued reference to
The cannula 216 is generally hollow and comprises a distal end 294 defining a tip 296 and a proximal end 298 mounted to the cannula support shaft 264 of the cannula mount 260. The tip 296 is preferably pointed for insertion through skin and into the tissue mass; however, the tip 296 can optionally be blunt, for example, if the marking apparatus 210 is utilized with a probe or the like. Preferably, the cannula 216 is a 17-gage (0.058 inch outer diameter) cannula, with an inner diameter ranging from 0.049 to 0.051 inches. Furthermore, the distal end 294 of the cannula 216 can be designed for enhanced visibility using common imaging techniques, such as radiography, ultrasonography, and magnetic resonance imaging (MRI), similar to the first embodiment cannula 16. The cannula 216 slidingly receives the stylet 218, which comprises a distal end 295 located in the cannula 216 and a proximal end 297 mounted to the stylet support shaft 276 of the stylet mount 262. Prior to use of the marking device 210, the distal end 295 of the stylet 216 is spaced inwardly from the tip 296 to form a marker recess 299 for housing the imaging marker 212.
When the marking device 210 is in an assembled condition, as shown in
Referring now to
After exposing the imaging marker 212, the cannula 216 continues to retract into the handle 214, and the cannula mount 260 contacts the stylet mount 262, as shown in
Proximal movement of the cannula mount 260 and the stylet mount 262 retracts the cannula 216 and the stylet 218 into the hollow interior 244 to a second retracted position and a withdrawn position, respectively. Proximal movement of the cannula mount 260 and the stylet mount 262 ceases when the stylet mount 262 abuts the proximal stop 268. Preferably, when the cannula 216 is in the retracted position, the entire cannula 216, including the tip 296, is received within the handle 214. Similarly, the entire stylet 218 is preferably received within the handle 214 when in the withdrawn position, but it within the scope of the invention for the distal end 295 to project from the nose 252 when the stylet 218 is in the withdrawn position.
In operation, a practitioner grasps the marking device 210 and inserts the cannula tip 296 through the skin of patient's body into a tissue mass. The practitioner places the tip 296 typically under the guidance of aforementioned imaging systems at or near a predetermined site, such as a biopsy site. Once the cannula tip 296 is at the predetermined site, the practitioner places an index finger or other suitable finger on the finger rest 290 of the trigger 288 and pivots the trigger 288 to move the trigger 288 from a locked position of
While the embodiments of the marking device 10, 210 according to invention have been shown and described as comprising an actuator that automatically retracts the cannula and the stylet, such as by force of a biasing element, the actuator can alternatively move the cannula and the stylet manually. For example, the actuator can comprise a slide operably coupled to the cannula mount, and proximal movement of the slide by the user can retract the cannula and the stylet or the cannula alone into the handle. The actuator can comprise a single actuator to effect movement of the cannula and the stylet or, alternatively, individual actuators for the cannula and the stylet. Further, while the first embodiment of the marking device 10 according to invention has been shown and described as comprising an actuator that manually advances the stylet to eject the imaging marker from the marker recess, the actuator can alternatively automatically advance the stylet, such as under the force of a biasing member.
The marking device according to the invention accurately implants the imaging marker at the predetermined site and, due to the retraction of the cannula into the handle, is safe to use. With the tip of the cannula retracted into the handle, the potential for the practitioner to injure himself/herself or others is eliminated. As a result, the practitioner can focus on the implanting procedure and does not have to be concerned with safety while withdrawing the marking device from the patient. Additionally, the actuator is easy to use and facilitates accurate implantation of the imaging marker.
While the embodiments of the marking device according to the invention have been shown and described with respect to implanting a single imaging marker, it is within the scope of the invention for the marking device to implant multiple imaging markers, either at the same location or different locations in the tissue mass. Additionally, the biasing element of the actuator is not limited to a spring, as shown and described in the above embodiments. It is within the scope of the invention to employ other types of baising elements. For example, the biasing element can comprise a source of compressed gas so that the stylet is advanced with air pressure, and the cannula and the stylet are retracted with a decrease in air pressure. Another example of a biasing element is a electric coil powered by a battery, and the coil in an energized size deploys the stylet and in de-energized state retracts the cannula and the stylet.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.
Claims
1-42. (canceled)
43. An actuator for a marking device comprising:
- a cannula mount configured to slidably support a cannula, the cannula mount comprises an elongated cannula support shaft;
- a stylet mount configured to slidably support a stylet, the stylet mount comprises an elongated stylet support shaft; and
- a trigger rotatably mounted to a trigger mount of a handle,
- wherein the actuator is mounted to the handle to effect movement of the stylet and the cannula to eject an imaging marker from the marking device and to retract the cannula into the handle following the ejection of the imaging marker from the marking device.
44. The actuator of claim 43, wherein the trigger is configured to move from a locked position to a stylet advance position to displace the stylet proximally and eject the imaging marker from the marking device.
45. The actuator of claim 43, wherein the trigger is configured to rotate relative to the cannula mount and stylet mount, wherein rotation of the trigger causes the stylet mount to move distally relative to the cannula mount.
46. The actuator of claim 43, wherein the trigger comprises:
- a distally-facing arcuate finger rest;
- an irregularly-shaped body;
- a first pivot member coupled to a first side of the irregularly-shaped body; and
- a second pivot member coupled to a second side of the irregularly-shaped body, wherein the first side is opposite the second side.
47. The actuator of claim 46, wherein the irregularly-shaped body is bounded by:
- a sloped upper surface extending proximally of the distally-facing arcuate finger rest;
- a generally-straight proximal surface, the sloped upper surface joined to the generally-straight proximal surface by a fillet; and
- a curved cam surface having a distal cam surface and a lower cam surface, the distal cam surface extends from the distally-facing arcuate finger rest to the lower cam surface, the lower cam surface terminates at the generally-straight proximal surface.
48. (canceled)
49. (canceled)
50. The actuator of claim 43, wherein
- the cannula mount further comprises: an annular body having an annular distal face, and a pair of diametrically opposed resilient prongs extending proximally from the annular body, and
- the stylet mount further comprises: a cylindrical body having a distal face, and a pair of diametrically opposed prong apertures on the distal face,
- wherein the pair of diametrically opposed prong apertures are configured to receive the pair of diametrically opposed resilient prongs of the cannula mount.
51. An actuator for a marking device comprising:
- a cannula mount configured to slidably support a cannula, the cannula mount comprising: an elongated cannula support shaft, an annular body having an annular distal face, a pair of diametrically opposed resilient prongs;
- a stylet mount configured to slidably support a stylet, the stylet mount comprising: an elongated stylet support shaft, a cylindrical body having a distal face, a pair of diametrically opposed prong apertures on the distal face, the pair of diametrically opposed prong apertures are configured to receive the pair of diametrically opposed resilient prongs of the cannula mount; and
- a trigger rotatably mounted to a trigger mount of a handle,
- wherein the actuator is mounted to the handle to effect movement of the stylet and the cannula to eject an imaging marker from the marking device and to retract the cannula into the handle following the ejection of the imaging marker from the marking device.
52. The actuator of claim 51, the cannula mount further comprising a pair of opposed legs, a first leg of the pair of opposed legs having a first arcuate outer surface and a first inner surface, a second leg of the pair of opposed legs having a second arcuate outer surface and a second inner surface, the pair of opposed legs extend proximally from the annular body.
53. The actuator of claim 51, wherein a first channel is formed on the first inner surface and a second channel is formed on the second inner surface.
54. The actuator of claim 52, wherein the pair of diametrically opposed resilient prongs is positioned between the pair of opposed legs of the cannula mount.
55. The actuator of claim 51, wherein the trigger is configured to move from a locked position to a stylet advance position to displace the stylet proximally and eject the imaging marker from the marking device.
56. The actuator of claim 51, wherein the trigger is configured to rotate relative to the cannula mount and stylet mount, wherein rotation of the trigger causes the stylet mount to move distally relative to the cannula mount.
57. (canceled)
58. (canceled)
59. The actuator of claim 51, further comprising:
- a cannula mount biasing member arranged to abut the annular distal face; and
- a stylet mount biasing member arranged between the annular body of the cannula mount and the distal face of the cylindrical body of the stylet mount.
60. The actuator of claim 59, wherein the cannula mount biasing member tapers from a cannula mount biasing member distal end to a cannula mount biasing member proximal end.
61. The actuator of claim 59, wherein a first prong of the pair of diametrically opposed resilient prongs comprises a first raised stop and a first outwardly-projecting tang on a first proximal end of the first prong, a second prong of the pair of diametrically opposed resilient prongs comprises a second raised stop and a second outwardly-projecting tang on a second proximal end of the second prong.
62. The actuator of claim 61, wherein the first raised stop and the second raised stop prevent proximal movement of the cannula mount.
63. An actuator for a marking device comprising:
- a cannula mount configured to slidably support a cannula, the cannula mount comprises an elongated cannula support shaft;
- a stylet mount configured to slidably support a stylet, the stylet mount comprises an elongated stylet support shaft; and
- a trigger rotatably mounted to a trigger mount of a handle, the trigger comprises: a distally-facing arcuate finger rest and an irregularly-shaped body, the irregularly-shaped body is bounded by: a sloped upper surface extending proximally of the distally-facing arcuate finger rest, a generally-straight proximal surface, the sloped upper surface joined to the generally-straight proximal surface by a fillet, and a curved cam surface having a distal cam surface and a lower cam surface, the distal cam surface extends from the distally-facing arcuate finger rest to the lower cam surface, the lower cam surface terminates at the generally-straight proximal surface,
- wherein the trigger is configured to rotate, the curved cam surface is configured to in sequence: ride along the stylet mount as the trigger rotates from a locked position to a cannula release position to displace the stylet mount to eject an imaging marker, and ride off the stylet mount as the trigger reaches a cannula release position to facilitate simultaneous proximal movement of the stylet mount and the cannula mount.
64. The actuator of claim 63, the cannula mount further comprising a pair of opposed legs, a first leg of the pair of opposed legs having a first arcuate outer surface and a first inner surface, a second leg of the pair of opposed legs having a second arcuate outer surface and a second inner surface, the pair of opposed legs extend proximally from the annular body.
65. The actuator of claim 64, wherein a first channel is formed on the first inner surface and a second channel is formed on the second inner surface.
66. The actuator of claim 64, wherein the pair of diametrically opposed resilient prongs is positioned between the pair of opposed legs of the cannula mount.
Type: Application
Filed: Feb 7, 2022
Publication Date: May 19, 2022
Inventors: Steven E. Field (Grand Rapids, MI), Ryan L. Goosen (Caledonia, MI), Richard E. Davis (Belding, MI), Richard M. Chesbrough (Bloomfield Hills, MI)
Application Number: 17/666,019