U.S. patent application number 10/045657 was filed with the patent office on 2003-05-01 for tissue separator assembly and method.
Invention is credited to Dubrul, William, Laird, Robert, Morrison, George.
Application Number | 20030083656 10/045657 |
Document ID | / |
Family ID | 22930569 |
Filed Date | 2003-05-01 |
United States Patent
Application |
20030083656 |
Kind Code |
A1 |
Morrison, George ; et
al. |
May 1, 2003 |
Tissue separator assembly and method
Abstract
A tissue separator assembly includes a proximal end assembly,
typically a handle, and a catheter assembly, including a shaft and
a tissue separator movable between a retracted state and an
outwardly extending, operational state. An energy source may be
selectively coupled to the tissue separator element. The tissue
separator element may be moved to the operational state and then
automatically rotated to separate a tissue section from the
surrounding tissue. A tissue holding element may be used to help
secure a separated tissue section to the catheter assembly. A
tubular braided element may be used to surround the tissue
separator element and any separated tissue section.
Inventors: |
Morrison, George; (San
Mateo, CA) ; Dubrul, William; (Redwood City, CA)
; Laird, Robert; (Pinole, CA) |
Correspondence
Address: |
HAYNES BEFFEL & WOLFELD LLP
P O BOX 366
HALF MOON BAY
CA
94019
US
|
Family ID: |
22930569 |
Appl. No.: |
10/045657 |
Filed: |
November 7, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60246413 |
Nov 7, 2000 |
|
|
|
Current U.S.
Class: |
606/45 |
Current CPC
Class: |
A61B 2017/1205 20130101;
A61B 2090/3908 20160201; A61B 2017/2215 20130101; A61B 2018/00214
20130101; A61B 18/148 20130101; A61B 2017/2212 20130101; A61B
2017/22061 20130101; A61B 18/1492 20130101; A61B 90/39 20160201;
A61B 17/221 20130101; A61B 2017/00867 20130101; A61B 2018/00601
20130101; A61B 90/02 20160201; A61B 2018/1475 20130101 |
Class at
Publication: |
606/45 |
International
Class: |
A61B 018/14 |
Claims
1. A tissue separator assembly comprising: a proximal end assembly;
a catheter assembly, extending from the proximal end assembly,
comprising: a shaft having a distal portion and defining an axis at
the distal portion; and an elongate tissue separator element having
a proximal part and a distal part, the distal part connected to the
distal portion of the shaft and movable between a retracted state,
adjacent to the distal portion, and an outwardly extending,
operational state; and the proximal end assembly comprising a first
driver, operably coupled to the tissue separator element,
constructed to (1) move the tissue separator element from the
retracted state to the operational state, and (2) automatically
rotate the tissue separator element about the axis, whereby a
tissue section is separable from surrounding tissue by the moving
tissue separator element.
2. The assembly according to claim 1 wherein the first driver is
constructed to automatically rotate the tissue separator element
after the tissue separator element is in the operational state.
3. The assembly according to claim 1 wherein first driver
automatically rotates the shaft and the tissue separator element
therewith about the axis.
4. The assembly according to claim 1 wherein the shaft has at least
one longitudinally extending bore.
5. The assembly according to claim 1 wherein the catheter assembly
comprises a hollow introducer sheath housing the shaft.
6. The assembly according to claim 1 wherein the distal part of the
tissue separator element comprises a wire.
7. The assembly according to claim 1 wherein the distal part of the
tissue separator element bows outwardly when in the operational
state.
8. The assembly according to claim 1 further comprising an energy
source selectively coupled to the tissue separator element.
9. The assembly according to claim 8 wherein the energy source
comprises an RF generator.
10. The assembly according to claim 1 wherein the first driver
comprises an actuator movable along a path from a first position,
to a second position and to a third position, said actuator
comprising a first part engageable with the proximal part of the
tissue separator element as the actuator moves between the first
and second positions so to move the distal part of the tissue
separator element from the retracted state to the operational
state.
11. They assembly according to claim 10 wherein the first driver
comprises a lead screw rotationally coupled to the shaft so
rotation of the lead screw causes the shaft to rotate.
12. The assembly according to claim 11 wherein the lead screw
comprises a rotary position indicator.
13. The assembly according to claim 12 wherein the lead screw has a
proximal end and the proximal end the comprises said indicator.
14. The assembly according to claim 11 wherein the first driver
comprises a lead nut rotationally mounted to the lead screw, said
lead nut and lead screw configured so that axial movement of the
lead nut causes rotational movement of the lead screw and the shaft
therewith.
15. The assembly according to claim 14 wherein the actuator
comprises a second part engageable with the lead nut as the
actuator moves from the second position to the third position
thereby causing the lead screw and the shaft and tissue separator
element therewith to rotate.
16. The assembly according to claim 1 wherein the catheter assembly
comprises a tissue section holding element at the distal portion of
the shaft, said holding element movable from a retracted condition
to an extended, tissue engaging condition so to help secure a
separated tissue section to the catheter assembly.
17. The assembly according to claim 16 wherein the tissue section
holding element comprises at least one wire having a pre-curved
distal end.
18. The assembly according to claim 16 wherein the proximal end
assembly comprises a second driver, operably coupled to the holding
element, constructed to move the holding element from the retracted
condition to the extended, tissue engaging condition.
19. The assembly according to claim 1 wherein the catheter assembly
comprises a tubular braided element at the distal portion of the
shaft movable longitudinally and radially between a proximal,
radially contracted state and a distal, radially expanded state
with said tubular braided element surrounding the tissue separator
element and any separated tissue section when in the distal,
radially expanded state.
20. They assembly according to claim 19 wherein the shaft comprises
an outwardly flaring guide surface to help guide the tubular
braided element along a tissue dissection between a separated
tissue section and surrounding tissue as the tubular braided
element moves from the proximal, radially contracted state to the
distal, radially expanded state.
21. The assembly according to claim 19 wherein the proximal end
assembly comprises a second driver, operably coupled to the tubular
braided element, constructed to move the tubular braided element
from the proximal, radially contracted state to the distal,
radially expanded state.
22. The assembly according to claim 1 wherein the catheter assembly
comprises: a tissue section holding element at the distal portion
of the shaft, said holding element movable from a retracted
condition to an extended, tissue engaging condition so to help
secure a separated tissue section to the catheter assembly; and a
tubular braided element at the distal portion of the shaft movable
longitudinally and radially between a proximal, radially contracted
state and a distal, radially expanded state with said tubular
braided element surrounding the tissue separator element and any
separated tissue section when in the distal, radially expanded
state.
23. The assembly according to claim 27 wherein the proximal end
assembly comprises a second driver, operably coupled to the holding
element and to the tubular braided element, constructed to: move
the holding element from the retracted condition to the extended,
tissue engaging condition and; move the tubular braided element
from the proximal, radially contracted state to the distal,
radially expanded state.
24. The assembly according to claim 23 wherein the second driver is
a manually operated driver.
25. A tissue separator assembly comprising: a proximal end
assembly; a catheter assembly, extending from the proximal end
assembly, comprising: a shaft having a distal portion and defining
an axis at the distal portion; and an elongate tissue separator
element having a proximal part and a distal part, the distal part
connected to the distal portion of the shaft and movable between a
retracted state, adjacent to the distal portion, and an outwardly
bowed, operational state; an energy source selectively coupled to
the tissue separator element; the proximal end assembly comprising
a first driver, operably coupled to the tissue separator element,
constructed to (1) move the tissue separator element from the
retracted state to the operational state, and thereafter (2)
automatically rotate the tissue separator element about the axis,
whereby a tissue section is separable from surrounding tissue by
the moving tissue separator element; the catheter assembly
comprising: a tissue section holding element at the distal portion
of the shaft, said holding element movable from a retracted
condition to an extended, tissue engaging condition so to help
secure a separated tissue section to the catheter assembly; a
tubular braided element at the distal portion of the shaft movable
longitudinally and radially between a proximal, radially contracted
state and a distal, radially expanded state with said tubular
braided element surrounding the tissue separator element and any
separated tissue section when in the distal, radially expanded
state; and the proximal end assembly comprising a second driver,
operably coupled to the holding element and to the tubular braided
element, constructed to: move the holding element from the
retracted condition to the extended, tissue engaging condition; and
move the tubular braided element from the proximal, radially
contracted state to the distal, radially expanded state.
26. The assembly according to claim 25 wherein: the first driver
comprises an actuator movable along a path from a first position,
to a second position and to a third position, said actuator
comprising a first part engageable with the proximal part of the
tissue separator element as the actuator moves between the first
and second positions so to move the distal part of the tissue
separator element from the retracted state to the operational
state; the first driver comprises a lead screw rotationally coupled
to the shaft so rotation of the lead screw causes the shaft to
rotate; the first driver comprises a lead nut rotationally mounted
to the lead screw, said lead nut and lead screw configured so that
axial movement of the lead nut causes rotational movement of the
lead screw; and the actuator comprises a second part engageable
with the lead nut as the actuator moves from the second position to
the third position thereby causing the lead screw and the shaft and
tissue separator element therewith to rotate.
27. A tissue separator assembly comprising: a proximal end
assembly; a catheter assembly, extending from the proximal end
assembly, comprising: a shaft having a distal portion and defining
an axis at the distal portion; and tissue separator means, at the
distal portion of the shaft and movable between a retracted state
and an extended, operational state, for passing through and
separating tissue; the proximal end assembly comprising means for
(1) moving the tissue separator means from the retracted state to
the extended, operational state, and (2) automatically rotating the
tissue separator element about the axis, whereby a tissue section
is separable from surrounding tissue.
28. The assembly according to claim 27 wherein the catheter
assembly comprises means for helping to secure a separated tissue
section to the catheter assembly.
29. The assembly according to claim 27 wherein the catheter
assembly comprises means for selectively enveloping the distal
portion of the shaft, the tissue separator means and any separated
tissue section.
30. A tissue separator assembly comprising: a proximal end
assembly; a catheter assembly, extending from the proximal end
assembly, comprising: a shaft having a distal portion and defining
an axis at the distal portion; and a movable tissue separator
element at the distal portion of the shaft; the proximal end
assembly comprising a first driver, operably coupled to the tissue
separator element, constructed to drive the tissue separator
element through tissue to separate a tissue section from
surrounding tissue; the catheter assembly comprising: a tissue
section holding element at the distal portion of the shaft, said
holding element movable from a retracted condition to an extended,
tissue engaging condition so to help secure a separated tissue
section to the catheter assembly; a tubular braided element at the
distal portion of the shaft movable longitudinally and radially
between a proximal, radially contracted state and a distal,
radially expanded state with said tubular braided element
surrounding the tissue separator element and any separated tissue
section when in the distal, radially expanded state; and the
proximal end assembly comprising a second driver, operably coupled
to the holding element and to the tubular braided element,
constructed to: move the holding element from the retracted
condition to the extended, tissue engaging condition; and move the
tubular braided element from the proximal, radially contracted
state to the distal, radially expanded state.
31. The assembly according to claim 30 wherein the first driver is
constructed to automatically rotate the shaft and the tissue
separator element therewith about the axis after the tissue
separator element is in the operational state.
32. The assembly according to claim 30 wherein the shaft has at
least one longitudinally extending bore.
33. The assembly according to claim 30 wherein the catheter
assembly comprises a hollow introducer sheath housing the
shaft.
34. The assembly according to claim 30 wherein the distal part of
the tissue separator element comprises a wire.
35. The assembly according to claim 30 further comprising an energy
source selectively coupled to the tissue separator element.
36. The assembly according to claim 35 wherein the energy source
comprises an RF generator.
37. The assembly according to claim 30 wherein the first driver
comprises an actuator movable along a path from a first position,
to a second position and to a third position, said actuator
comprising a first part engageable with the proximal part of the
tissue separator element as the actuator moves between the first
and second positions so to move the distal part of the tissue
separator element from the retracted state to the operational
state.
38. They assembly according to claim 37 wherein the first driver
comprises a lead screw rotationally coupled to the shaft so
rotation of the lead screw causes the shaft to rotate.
39. The assembly according to claim 38 wherein the lead screw
comprises a rotary position indicator.
40. The assembly according to claim 39 wherein the lead screw has a
proximal end and the proximal end the comprises said indicator.
41. The assembly according to claim 38 wherein the first driver
comprises a lead nut rotationally mounted to the lead screw, said
lead nut and lead screw configured so that axial movement of the
lead nut causes rotational movement of the lead screw and the shaft
therewith.
42. The assembly according to claim 41 wherein the actuator
comprises a second part engageable with the lead nut as the
actuator moves from the second position to the third position
thereby causing the lead screw and the shaft and tissue separator
element therewith to rotate.
43. The assembly according to claim 30 wherein the tissue section
holding element comprises at least one wire having a pre-curved
distal end.
44. They assembly according to claim 30 wherein the shaft comprises
an outwardly flaring guide surface to help guide the tubular
braided element along a tissue dissection between a separated
tissue section and surrounding tissue as the tubular braided
element moves from the proximal, radially contracted state to the
distal, radially expanded state.
45. The assembly according to claim 30 wherein the second driver is
a manually operated driver.
46. A tissue separator assembly comprising: a proximal end
assembly; a catheter assembly, extending from the proximal end
assembly, comprising tissue separator means for passing through and
separating tissue; the proximal end assembly comprising a first
driving means for driving the tissue separator means through tissue
to separate a tissue section from surrounding tissue; the catheter
assembly comprising; tissue puncturing means for helping to secure
a separated tissue section to the catheter assembly; and means for
surrounding the tissue separator means and any separated tissue
section; and the proximal end assembly comprising a second driving
means for: driving the tissue puncturing means into a separated
tissue section; and driving the surrounding means.
47. A method for creating a tissue section within surrounding
tissue comprising: positioning a distal end of a catheter assembly
at a target location within a patient, the catheter assembly
defining an axis; moving an elongate tissue separator element, at
the distal end of the catheter assembly, from a radially retracted
state to an outwardly extending, operational state; and
automatically, following at least the start of the separator
element moving step, rotating the separator element about the axis
to separate a tissue section from surrounding tissue.
48. The method of according to claim 47 further comprising
supplying energy to the separator element.
49. The method of according to claim the 48 wherein the energy
supplying step comprises supplying RF energy to the separator
element.
50. The method of according to claim 47 wherein the automatically
rotating step begins after the separator element has reached the
operational state.
51. The method according to claim 47 wherein the automatically
rotating step is carried out by rotating the separator element
about 540.degree. about the axis.
52. The method according to claim 47 further comprising moving a
tissue holding element, located at the distal end of the catheter
assembly, from a retracted condition to an extended, tissue
engaging condition.
53. The method according to claim 52 wherein the tissue holding
element moving step is carried out following the automatically
rotating step.
54. The method according to claim 52 wherein the tissue holding
element moving step is carried out using at least one wire having a
pre-curved distal end.
55. The method according to claim 47 further comprising surrounding
the separated tissue section with a tubular braided element by
moving the tubular braided element, located at the distal end of
the catheter assembly, from a proximal, radially contracted state
to a distal, radially expanded state following the automatically
rotating step.
56. A method for creating a tissue section within surrounding
breast tissue of a patient comprising: positioning a distal end of
a catheter assembly at a target location within the breast of a
patient, the catheter assembly defining an axis; moving an elongate
tissue separator element, at the distal end of the catheter
assembly, from a radially retracted state to a radially extended,
outwardly bowed, operational state; supplying energy to the
separator element; automatically, following the separator element
moving step, rotating the separator element about the axis to
separate a tissue section from surrounding tissue; moving a tissue
holding element, located at the distal end of the catheter
assembly, from a retracted condition to an extended, tissue
engaging condition; and surrounding the separated tissue section
with the tubular braided element by moving the tubular braided
element, located at the distal end of the catheter assembly, from a
proximal, radially contracted state to a distal, radially expanded
state following the automatically rotating step.
57. The method of according to claim the 56 wherein the energy
supplying step comprises supplying RF energy to the separator
element.
58. The method of according to claim 56 wherein the automatically
rotating step begins after the separator element has reached the
operational state.
59. The method according to claim 56 wherein the automatically
rotating step is carried out by rotating the separator element
about 540.degree. about the axis.
60. The method according to claim 56 wherein the tissue holding
element moving step is carried out following the automatically
rotating step.
61. The method according to claim 56 wherein the tissue holding
element moving step is carried out using at least one wire having a
pre-curved distal end.
Description
CROSS REFERENCE TO OTHER APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 60/246,413 filed Nov. 7, 2000 and entitled
Tissue Therapy and/or Removal Apparatus and Methods for Use. See
also: (1) U.S. Pat. No. 6,179,860 issued Jan. 30, 2001 and entitled
Target Tissue Localization Device And Method, (2) International
Publication No. WO 00/10471 published Mar. 2, 2000 and entitled
Target Tissue Localization Device And Method, (3) U.S. Pat. No.
6,221,006 issued Apr. 24, 2001 and entitled Entrapping Apparatus
And Method For Use, (4) International Publication No. WO 99/39648
published Aug. 12, 1999 and entitled Entrapping Apparatus And
Method For Use, (5) U.S. patent application Ser. No. 09/588,278
filed Jun. 5, 2000 and entitled Tissue Removal Methods And this
Apparatus, and (6) International Publication No. WO 00/74561
published Dec. 14, 2000 and entitled Tissue Removal Methods And
Apparatus.
BACKGROUND OF THE INVENTION
[0002] The M. D. Anderson Cancer Center in Houston, Texas predicts
that cancer will become the leading cause of death in the United
States by the year 2002. Cancer presently results in over one
thousand five hundred deaths every day in the United States
(550,000 deaths every year). Therapy modalities for cancer are
plentiful and continued to be researched with vigor. Still, the
preferred treatment continues to be physical removal of the cancer.
When applicable, surgical removal is preferred (breast, colon,
brain, lung, kidney, etc.). Open, excisional, surgical removal is
often extremely invasive so that efforts to remove cancerous tissue
in less invasive ways continue, but have not yet been
perfected.
[0003] The only cure for cancer continues to be the early diagnosis
and subsequent early treatment. As cancer therapies continue at
earlier stages of diagnosis, the cancerous tissue being operated on
is also smaller. Early removal of the smaller cancers demand new
techniques for removal and obliteration of these less invasive
cancers.
[0004] There are a variety of techniques that attempt to accomplish
less invasive cancer therapy, but so far without sufficiently
improved results. For example, the ABBI system from U.S. Surgical
Corporation and the Site Select system from ImaGyn Corporation,
attempt to accomplish less invasive cancer therapy. However,
conventional techniques require more than Minimally Invasive
Surgery (MIS) techniques in that they require a large core (that is
more than about 15 mm diameter) incision. Additionally, the
Mammotome system from Johnson and Johnson and MIBB system from U.S.
Surgical Corporation also require large core (over about 4 mm
diameter) access to accomplish biopsy.
[0005] A recent convention held by the American Society of Surgical
Oncologists on Mar. 13, 2000 reported that conventional
stereotactic core biopsy (SCB) procedures fall short in providing
definitive answers to detail precise surgical regimens after this
SCB type vacuum assisted biopsy, especially with ductile carcinoma
in situ (DCIS). Apparently these percutaneous systems damage
"normal" tissue cells so that it is difficult to determine if the
cells are "normal damaged" cells or early pre-cancerous (e.g.
Atypical Ductal Hyerplasia (ADH)) cells.
[0006] A study presented by Dr. Ollila et al. from the University
of North Carolina, Chapel Hill, demonstrated that histology and
pathology is compromised using these conventional techniques
because of the damage done to the removed tissue specimens. Hence,
for many reasons, including the fact that DCIS is becoming more
detectable and hence more prevalent in breast cancer diagnosis in
the U.S., there is a growing need to improve upon conventional
vacuum assisted core biopsy systems.
SUMMARY OF THE INVENTION
[0007] One aspect of the invention is directed to a tissue
separator assembly including the proximal end assembly, typically a
handle, and catheter assembly extending from the proximal end
assembly. The catheter assembly includes a shaft and an elongate
tissue separator element, a distal part of which is movable between
a retracted state and an outwardly extending, operational state.
The proximal end assembly includes a first driver coupled to the
tissue separator element and constructed to (1) to move the tissue
separator element from the retracted state to the operational
state, and (2) automatically rotate the tissue separator element
about the axis, whereby a tissue section is separable from the
surrounding tissue by the moving tissue separator element.
[0008] Another aspect of the invention is directed to a tissue
separator assembly including the proximal end assembly, typically a
handle, and catheter assembly extending from the proximal end
assembly. The catheter assembly includes a shaft and an elongate
tissue separator element, a distal part of which is movable between
a retracted state and an outwardly bowed, operational state. An
energy source is selectively coupled to the tissue separator
element. The proximal end assembly includes a first driver coupled
to the tissue separator element and constructed to (1) to move the
tissue separator element from the retracted state to the
operational state, and (2) automatically rotate the tissue
separator element about the axis, whereby a tissue section is
separable from the surrounding tissue by the moving tissue
separator element. The catheter assembly also includes a tissue
holding element at the distal portion of the shaft movable from a
retracted condition to an extended, tissue engaging condition so to
help secure a separated tissue section to the catheter assembly.
The catheter assembly further includes a tubular braided element at
the distal portion of the shaft movable to a radially expanded
state so to surround the tissue separator element and any separated
tissue section. The proximal end assembly also includes a second
driver coupled to the holding element and to the tubular braided
element. The second driver is constructed to move the holding
element to the extended, tissue engaging condition and move the
tubular braided element to the distal, radially expanded state.
[0009] Another aspect of the invention is directed to a tissue
separator assembly including the proximal end assembly, typically a
handle, and catheter assembly extending from the proximal end
assembly. The catheter assembly includes a shaft and a movable
tissue separator element. The proximal end assembly includes a
first driver coupled to the tissue separator element and
constructed to drive the tissue separator element through tissue to
separate a tissue section from surrounding tissue. The catheter
assembly also includes a tissue holding element at the distal
portion of the shaft movable from a retracted condition to an
extended, tissue engaging condition so to help secure a separated
tissue section to the catheter assembly. The catheter assembly
further includes a tubular braided element at the distal portion of
the shaft movable to a radially expanded state so to surround the
tissue separator element and any separated tissue section. The
proximal end assembly also includes a second driver coupled to the
holding element and to the tubular braided element. The second
driver is constructed to move the holding element to the extended,
tissue engaging condition and move the tubular braided element to
the distal, radially expanded state.
[0010] A further aspect of the invention is directed to a method
for creating a tissue section within surrounding tissue. The method
includes positioning a distal end of a catheter assembly at a
target location within a patient. An elongate tissue separator
element, at the distal end of the catheter assembly, is moved to an
outwardly extending, operational state. The separator element is
automatically rotated about the axis, following at least the start
of the separator element moving step, so to separate a tissue
section from surrounding tissue. The method may also include moving
a tissue holding element, located at the distal end of the catheter
assembly, from a retracted condition to an extended, tissue
engaging condition. Further, the method may include surrounding the
separated tissue section with a tubular braided element.
[0011] A still further aspect of the invention is directed to a
method for creating a tissue section within surrounding tissue. The
method includes positioning a distal end of the catheter assembly
at a target location within a breast of a patient. An elongate
tissue separator element, at the distal end of the catheter
assembly, is moved to a radially extended, outwardly bowed,
operational state. Energy is supplied to the separator element. The
separator element is automatically rotated about the axis,
following at least the start of the separator element moving step,
so to separate a tissue section from surrounding tissue. A tissue
holding element, located at the distal end of the catheter
assembly, is moved from a retracted condition to an extended,
tissue engaging condition. The separated tissue section is
surrounded by a tubular braided element by moving the tubular
braided element, located at the distal end of the catheter
assembly, from a proximal, radially contracted state to a distal,
radially expanded state following the automatically rotating
step.
[0012] Other features and advantages of the invention will appear
from the following description in which the preferred embodiments
have been set forth in detail in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a partially schematic overall view of a tissue
separator assembly made according to the invention with portions of
the handle removed for clarity;
[0014] FIG. 1A is a simplified cross-sectional view taken along
line 1A-1A of FIG. 1 showing the engagement of a pin within a slot
in the lead nut mounted to the lead screw;
[0015] FIG. 2 is schematic view of portions of the drive elements
of the assembly of FIG. 1;
[0016] FIG. 3 is a simplified cross-sectional view of the catheter
assembly taken along line 3-3 of FIG. 1;
[0017] FIG. 4 is an oblique view of the housing half of FIG. 1
together with the drive screw, drive nut and an L-shaped actuator
connected to and movable with the drive nut;
[0018] FIGS. 5 and 6 show the handle and catheter assembly of FIG.
1 after the actuator has moved from the position of FIG. 1 and the
actuator extension has pushed the separator wire pusher screw in a
distal direction causing the separator wire to move radially
outwardly;
[0019] FIG. 7 is a simplified the end view of the block and the
pusher screw just after the pusher screw has exited the slot in the
block showing the off-vertical orientation of the pusher screw;
[0020] FIG. 8 illustrates the proximal end of the lead screw, which
is visible from outside the housing, and a rotary position
indicator marked thereon corresponding to the position of the
separator wire in FIG. 10;
[0021] FIGS. 9 and 10 illustrate the structure of FIGS. 5 and 6
after the drive screw has moved the actuator distally causing the
lead nut to rotate the lead screw, catheter shaft and separator
wire therewith about 540 degrees to create a separated tissue
section;
[0022] FIGS. 11 and 12 illustrate the manual actuation of tissue
section holding elements;
[0023] FIG. 13 is a simplified view of certain of the components of
FIG. 12;
[0024] FIG. 14 is a cross-sectional view of the catheter taken
along line 14-14 of FIG. 13;
[0025] FIGS. 15 and 16 illustrate the manual actuation of a tubular
braided element to surround the separated tissue section; and
[0026] FIG. 17 is a simplified view of certain of the components of
FIG. 16.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0027] FIGS. 1 and 2 illustrate a tissue separator assembly 10 used
to separate target tissue from surrounding tissue, typically within
a patient's breast. The removal of target tissue may be for
diagnostic or therapeutic purposes. The assembly 10 includes a
catheter assembly 12 extending from a handle 14. Introduction of
catheter assembly 12 into the patient, typically through the skin,
is preferably aided by the use of, for example, a trocar or an RF
tip to provide a suitable path through the tissue. A stepper motor
16 is connected to handle 14 by a drive drive cable 18 and a drive
cable connector 20 mounted to the handle housing 22. Note that in
the figures only one-half of handle housing 22 is shown; the other
housing half is substantially similar. RF energy is supplied to
catheter assembly 12 from an RF source 24, along drive cable 18 and
to the interior of handle 14. A controller 26 controls the
operation of stepper motor 16 as well as RF source 24, such as
speed of operation and energy level. Controller 26 also receives
appropriate feedback signals from handle 14 and catheter assembly
12, such as tissue temperature, resistance force signals, rotary
orientation, and so forth.
[0028] Drive cable 18 is connected to and rotates a drive screw 28
rotatably mounted within handle 14 at a fixed axial location by
drive screw supports 30, 32. A drive nut 34 is threadably mounted
to drive screw 28. An L-shaped actuator 36 is secured to drive nut
34. Actuator 36, see FIG. 4, includes a generally horizontal base
portion 38 and a generally vertical upright portion 40 sized and
configured to move within handle 14 parallel to the axis of drive
screw 28. Therefore, rotation of drive screw 28 by stepper motor 16
causes actuator 36 to slide within housing 22 from the initial
position of FIG. 1 to the position of FIG. 10. Reverse and
reciprocating movement is also possible.
[0029] Catheter assembly 12 includes in introducer sheath 42
mounted to and extending from housing 22. Catheter assembly 12 also
includes an actuator tube 43, discussed below with reference to
FIGS. 14-17, passing through sheath 42 and a shaft 44 passing
through tube 43. See FIG. 3. Shaft 44 has a distal portion 46
extending distally of the distal end 48 of sheath 42 and a proximal
portion 50 extending into the interior of handle 14. Proximal
portion 50 is secured to and rotates with a lead screw 52.
Accordingly, shaft 44 rotates with lead screw 52. Lead screw 52 is
mounted within housing 22 in a manner so that it can rotate but not
move axially within housing 22. A tissue separator device 54
extends along shaft 44 and has a separator wire portion 56 secured
to the distal end 58 of shaft 44. The separator wire 56 is
positioned externally of distal portion 46. The majority of tissue
separator device 54 is in the form of a wire and extends through an
axial bore 60 formed in shaft 44. The separator device 54 has a
radially extending pusher screw 62 at its proximal end. The
proximal end of shaft 44 has an axially extending slot 64, see FIG.
2, through which pusher screw 62 extends. Accordingly, pushing
pusher screw 62 distally, that is to the left in the figures,
causes tissue separator wire 56 to move outwardly from its radially
contracted condition of FIG. 1 to its radially extended condition
of FIGS. 5 and 6. This radially outwardly movement is typically
accomplished at the target site within the patient, typically a
patient's breast. To aid movement of separator wire through the
tissue, wire 56 is supplied with RF energy from RF source 24. Other
applications of energy, such as mechanical reciprocation or
mechanical vibration, can also be used.
[0030] The axial movement of pusher screw 62 is caused by the axial
movement of actuator 36. Actuator 36 has an extension 66 extending
distally from upright portion 40. Extension 66 has a downwardly
formed distal end 68 aligned with pusher screw 62. The initial
axial movement of actuator 40, caused by the rotation of drive
screw 28 by stepper motor 16, closes a small gap 70 (see FIG. 2)
between distal end 68 and pusher screw 62. This small gap permits
the initiation of an electrosurgical arc prior to the outwardly
radial movement of separator wire 56. Continued distal movement of
actuator 36 moves pusher screw 62 distally causing separator wire
56 to bow outwardly to the position of FIGS. 5 and 6. FIGS. 5 and 6
(but not FIG. 1) show the use of a support block 72, which is a
part of housing 22, to support the distal end of lead screw 52 and
the proximal end of shaft 44. Support block 72 has an axially
extending slot 74, see FIGS. 5 and 7, which initially houses pusher
screw 62. At the time support wire 56 is fully extended, pusher
screw 62 exits slot 74 and the distal end 68 of extension 66, which
has a chamfered face, causes pusher screw 62, along with shaft 44,
to begin rotating to the off-vertical position of FIG. 7. At the
same time upright portion 40 of actuator 36 closes gap 73 (see FIG.
2) and contacts a lead nut 75 threadably mounted on lead screw 52.
An anti-rotation pin 76 extends from upright portion 40 of actuator
36 and is housed within a U-shaped slot 78 formed in lead nut 74,
see FIG. 1A, to prevent lead nut 74 from rotating around lead screw
52 as lead nut 74 it is moved axially by actuator 36. Instead, the
axial movement of actuator 36 causes lead screw 52 to rotate thus
rotating shaft 44. Assembly 10 is configured so that shaft 44
rotates about 540 degrees to ensure a tissue section 80 is
completely separated from the surrounding tissue by the passage of
separator wire 56 through the tissue. The radial position of
separator wire 56 can be easily determined by looking at the
proximal end 82 of lead screw 52, which is exposed through housing
22. See FIG. 8. Proximal end 82 has a rotary position indicator 84
formed thereon corresponding to the rotary position of separator
wire 56.
[0031] The above described sequence of events, according to this
disclosed embodiment, proceeds automatically once initiated by a
user. Of course operation of the device, including one or more of
extension of separator wire 56, rotation of shaft 44 and energizing
wire 56, can be terminated manually or automatically based on, for
example, an unexpected resistance to the rotation of shaft 44. With
the disclosed embodiment the following events proceed manually;
however, the assembly could be designed so that any or all of the
following could be accomplished automatically.
[0032] Assembly 10 also includes a T-pusher device 86 having a pair
of pusher tabs 88 extending laterally outwardly from slots formed
in housing 22. See FIGS. 11-13. After shaft 44 has completed its
rotation, the user begins pushing tabs 88 distally. This causes an
extension 90 of device 86 to rotate a flipper cam 92 about a pivot
pin 94; flipper cam 92 is connected to the proximal ends of a pair
of tissue section holding elements 96. Holding elements 96 are in
the form of wires passing through axial bores 98 formed in shaft 44
as shown in FIG. 3. The distal ends of holding elements 96 are
preformed hook wires 100, preferably made of a shape memory
material such as nitinol, which pass through openings formed in
distal portion 46 of shaft 44 and engage separated tissue section
80 to help secure tissue section 80 to distal portion 46 of shaft
44.
[0033] Device 86 includes a distal end 102 connected to the
proximal end of actuator tube 43. Thus, the movement of device 86
causes tube 43 to move distally within introducer sheath 42. At
this point, that is with hook wires 100 deployed as an FIGS. 11-13,
a tubular braided element 104, see FIGS. 14-17, secured to the
distal end of actuator tube 43, is still fully housed within sheath
42. Further distal movement of device 86 causes tubular braided
element 104 to extend outwardly past distal end 48 of sheath 42 to
the position of FIGS. 15-17. The purpose of tubular braided element
104 is to surround separated tissue section 80 by passing along the
dissection plane between the separated tissue section and the
surrounding tissue. The open outer end 106 of element 104 naturally
expands radially as it is pushed axially through the tissue. To aid
the proper initial radial expansion of element 104, shaft 44 has an
outwardly tapered guide surface 108, formed on a guide element 110,
positioned adjacent to distal end 48 of introducer shaft 42. Guide
element 110 has a slot in its proximal surface into which the
proximal end of separator wire 56 passes when in the radially
expanded condition of FIG. 9; this helps to keep separator wire 56
from folding over during rotation. If desired, outer end 106 of
tubular braided element 104 could include a drawstring or other
type of closure element. The separated tissue section 80, now
substantially enclosed within tubular braided element 104 and
secured to distal portion 46 of shaft 44 by hook wires 100, may be
removed from the patient.
[0034] With the present invention separated tissue section 80
retains most if not all of its physical integrity once removed from
the patient. Also, the use of tubular braided element 104,
especially when it is sealed or otherwise impermeable to the
passage of material, helps to reduce the possibility of seeding
diseased tissue along the tissue tract during removal of separated
tissue section 80.
[0035] Modification and variation can be made to be disclosed
embodiments without departing from the subject of the invention as
defined in the following claims. For example, a target tissue
localization device, such as disclosed in U.S. Pat. No. 6,179,860,
may be incorporated into assembly 10; such a localization device
would be deployed, as indicated by dashed lines 112 in FIG. 1 and
localization device actuator shaft 114 in FIG. 18, after placement
of distal portion 46 of shaft 44 at the target site and would be
used to help stabilize the assembly and also help contain, in
conjunction with a tubular braided element 104, separated tissue
section 80. Lead screw 52 could be hollow to permit actuator shaft
114, or other medical devices, to pass therethrough and into a
lumen within shaft 44. Instead of stepper motor 16, drive screw 28
and drive nut 34, other driving mechanisms, such as spring driven
drivers with appropriately configured escape mechanisms and/or
movement damping devices, could be used. In the preferred
embodiment shaft 44 does not begin to rotate until after separator
wire 56 has reached its fully radially extended state. In some
situations it may be desired to begin rotating shaft 44 before
and/or during the outward movement of separator wire 56.
[0036] Any and all patents, patent applications and printed
publications referred to above are hereby incorporated by
reference.
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