U.S. patent application number 15/486078 was filed with the patent office on 2017-12-28 for esophageal ablation technology.
The applicant listed for this patent is Seth Crozier, Sohail Desai, Bryce Alexander Igo, Dan Kasprzyk. Invention is credited to Seth Crozier, Sohail Desai, Bryce Alexander Igo, Dan Kasprzyk.
Application Number | 20170367760 15/486078 |
Document ID | / |
Family ID | 60675759 |
Filed Date | 2017-12-28 |
United States Patent
Application |
20170367760 |
Kind Code |
A1 |
Crozier; Seth ; et
al. |
December 28, 2017 |
ESOPHAGEAL ABLATION TECHNOLOGY
Abstract
An esophageal ablation system including a positioner, an
elongated, flexible shaft extending from the positioner, and a
microwave emitter assembly disposed near the distal end of the
shaft. The emitter assembly includes one or more microwave antennae
and a balloon tor spacing the antennae relative to target tissue.
The device may have an inner balloon for deploying the antenna. The
systems, devices and methods disclosed are useful for treating
Barrett's Esophagus, Esophageal Adenocarcinoma, and Squamous Cell
Carcinoma.
Inventors: |
Crozier; Seth; (Flagstaff,
AZ) ; Desai; Sohail; (Sacramento, CA) ;
Kasprzyk; Dan; (Flagstaff, AZ) ; Igo; Bryce
Alexander; (Flagstaff, AZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Crozier; Seth
Desai; Sohail
Kasprzyk; Dan
Igo; Bryce Alexander |
Flagstaff
Sacramento
Flagstaff
Flagstaff |
AZ
CA
AZ
AZ |
US
US
US
US |
|
|
Family ID: |
60675759 |
Appl. No.: |
15/486078 |
Filed: |
April 12, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62321239 |
Apr 12, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 2018/00255
20130101; A61B 2018/00982 20130101; A61B 2018/1876 20130101; A61B
2018/0022 20130101; A61B 2018/00208 20130101; A61B 2018/1823
20130101; A61B 2018/00791 20130101; A61B 2018/00196 20130101; A61B
18/1815 20130101; A61B 2018/00488 20130101; A61B 2018/1861
20130101; A61B 2018/00184 20130101; A61B 2018/00577 20130101 |
International
Class: |
A61B 18/18 20060101
A61B018/18 |
Claims
1. An microwave thermal ablation system for human medical therapy,
comprising: a microwave generator; at least one microwave emitter
communicatively connected to the microwave generator, the microwave
emitter being adapted to being inserted into the body of a patient;
a medical balloon inflation means; and a positioning balloon
connected to the balloon inflation means and to the at least one
microwave emitter for holding the at least one microwave emitter in
a desired position relative to a target tissue or tissues within
the body of a patient.
2. The microwave thermal ablation system of claim 1, wherein the
microwave generator provides 17-18 GHz frequency power to the at
least one microwave emitter via a power line.
3. The microwave thermal ablation system of claim 1, wherein the at
least one microwave emitter is selected from the group of emitters
consisting of coaxial antenna, planar antenna, patch type,
tri-axial antenna, slot antenna, helical antenna, bow-tie antenna,
dipole antenna, broad band antennas and narrow band antennas.
4. The microwave thermal ablation system of claim 3, wherein the at
least one emitter is constructed, and arranged of a plurality of
individual emitters in an array.
5. The microwave thermal ablation system of claim 3, wherein the at
least one emitter is single, direct fed, patch type antenna that
has a radius curved surface.
6. The microwave thermal ablation system of claim 3 wherein the
balloon inflation means provides a one way or reversible gas or
liquid fluid to the positioning balloon via a fluid conduit.
7. The microwave thermal ablation system of claim 1, wherein the
positioning balloon is disposed on a catheter having at least one
lumen for power connection between the microwave generator and the
at least one microwave emitter, and fluid communication between the
balloon inflation means and the positioning balloon.
8. The microwave thermal ablation system of claim 7, wherein the
positioning balloon is disposed around the at least one microwave
emitter.
9. The microwave thermal ablation system of claim 8, whereby, in
use, (a) the catheter is inserted into a patient's body with the
balloon in an uninflated state, (b) the at least one microwave
emitter and surrounding positioning balloon are moved to a desired
position near target tissue that is to be thermally ablated, (c)
the positioning balloon is inflated to a desired diameter, (d) the
at least one microwave emitter is held in a fixed position near the
target tissue by the positioning balloon, and (e) microwave power
is delivered from the microwave generator to the at least one
microwave for a predetermined period of time, at a predetermined
frequency and at a predetermined phase.
10. The microwave thermal ablation system of claim 9, wherein the
predetermined time, frequency, and/or phase is modulated.
11. The microwave thermal ablation system of claim 8, wherein the
at least one microwave antenna is disposed in a fixed position on
the catheter, whereby the at least one microwave antenna is at
least generally centrally disposed within the positioning
balloon.
12. The microwave thermal ablation system of claim 8, wherein the
at least one microwave antenna is movable away from the catheter
when, in use, the positioning balloon is in an inflated state.
13. The microwave thermal ablation system of claim 12, wherein the
system further comprises an emitter deployment balloon connected to
the catheter and disposed within the positioning balloon, the
emitter deployment balloon being constructed and arranged to be
inflatable to move the at least one microwave emitter a
predetermined distance away from the catheter, whereby the at least
one microwave emitter is disposed off center relative to a central
axis of the catheter/positioning balloon assembly, and thereby
closer to one portion of the circumferential wall of the inflated
positioning balloon.
14. The microwave thermal ablation system of claim 13, wherein the
catheter includes an emitter deployment balloon inflation fluid
lumen communicatively extending from the emitter deployment balloon
to the balloon inflation means.
15. The microwave thermal ablation system of claim 12, wherein the
system further comprises an extendable scaffolding assembly
connected to the catheter and to the at least one microwave
emitter, and disposed within the positioning balloon, the
scaffolding system having a low profile, non-extended state where
the at least one microwave emitter is disposed near the center axis
of the catheter and an extended state to move the at least one
microwave emitter a predetermined distance away from the catheter,
whereby the at least one microwave emitter is disposed off center
relative to a central axis of the catheter/positioning balloon
assembly, and thereby closer to one portion of the circumferential
wall of the inflated positioning balloon.
16. The microwave thermal ablation system of claim 15, wherein the
scaffolding assembly comprises a centering bottom link connected to
the catheter, a mandrel connected to the centering bottom link, a
pull link connected to the mandrel, a pair of pivotable expansion
links connected at their lower ends to the centering bottom link
and the pull link, and an antenna mount connected to the upper ends
of the expansion link.
17. The microwave thermal ablation system of claim 16, wherein the
catheter includes (a) a tip extending distally away from the
positioning balloon, (b) the tip having a central lumen open to the
distal end of the system, and (c) a telescoping slide shaft is
disposed on the central lumen of the distal tip and connecting the
distal end of the centering bottom link.
18. The microwave thermal ablation system of claim 1, further
comprising a catheter shaft including (a) at least power line
electrically connecting the microwave generator and the at least
one microwave generator, and (b) at least one lumen communicatively
fluidly connecting the balloon inflation means and the positioning
balloon, the at least one microwave emitter and the positioning
balloon being coupled to the catheter shaft at a predetermined
position, the catheter shaft being adapted to being inserted into
the body of a patient and for translating the at least one
microwave emitter and the positioning balloon within and through
the patient's body.
19. The microwave thermal ablation system of claim 18, further
comprising a handle connected to a proximal, end of the catheter
shaft.
20. The microwave thermal ablation system of claim 8, further
comprising means to visually track the position of the at least one
microwave emitter in the patient's body during use of the
system.
21. The microwave thermal ablation system of claim 20, wherein the
means to visually track includes the positioning balloon being at
least partially constructed of material that is transparent to
users during radiographic and/or endoscopic visualization.
22. The microwave thermal ablation system of claim 1, wherein at
least a portion of the positioning balloon is constructed of
material that shields microwave radiation.
23. The microwave thermal ablation system of claim 1 further
comprising at least one sensor selected from the group consisting
of thermocouples, temperature sensors, and thermistors.
24. The microwave thermal ablation system of claim 1 for use to
treat Barrett's Esophageal cells via non-contact dielectric
heating.
25. An microwave thermal ablation system for use in treating
Barrett's Esophageal ceils via non-contact dielectric heating,
comprising: a. a microwave generator for providing 915 MHz to 20
GHz microwave energy; b. at least one microwave emitter
communicatively connected to the microwave generator, the microwave
emitter being adapted to being inserted into the body of a patient;
c. a medical balloon inflation means; d. a positioning balloon
connected to the balloon inflation means and to the at least one
microwave emitter for holding the at least one microwave emitter in
a desired position relative to a target tissue or tissues within
the body of a patient, the positioning balloon being disposed
around the at least one microwave emitter; and e. a catheter shaft
including: ii) at least power line electrically connecting the
microwave generator and the at least one microwave generator, and
(ii) at least one lumen communicatively fluidly connecting the
balloon inflation means and the positioning balloon, the at least
one microwave emitter and the positioning balloon being coupled to
the catheter shaft at a predetermined position, the catheter shaft
being adapted to being inserted into the body of a patient and for
translating the at least one microwave emitter and the positioning
balloon within and through the patient's body.
26. A microwave thermal ablation method for human medical therapy,
comprising the steps of: a. providing a system including i. a
microwave generator; ii. at least one microwave emitter
communicatively connected to the microwave generator, the microwave
emitter being adapted to being inserted into the body of a patient;
iii. a medical balloon inflation means; iv. a positioning balloon
connected to the balloon inflation means and to the at least one
microwave emitter for holding the at least one microwave emitter in
a desired position relative to a target tissue or tissues within
the body of a patient; and v. wherein the positioning balloon is
disposed on a catheter having at least one lumen for power
connection between the microwave generator and the at least one
microwave emitter, and fluid communication between the balloon
inflation means and the positioning balloon; b. inserting the
catheter into a patient's body with the balloon in an uninflated
state, c. moving the at least one microwave emitter and surrounding
positioning balloon to a desired position near target tissue that
is to be thermally ablated, d. inflating the positioning balloon to
a desired diameter, thereby holding the at least one microwave
emitter in a fixed position near the target tissue by the
positioning balloon, and e. delivering microwave power from the
microwave generator to the at least one microwave for a
predetermined period of time, at a predetermined frequency and at a
predetermined phase.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS, IF ANY
[0001] This application claims the benefit under 35 U.S.C.
.sctn.119(e) of co-pending U.S. Provisional Patent Application Ser.
No. 62/321,239, filed Apr. 12, 2016, which is hereby incorporated
by reference.
37 C.F.R. .sctn.1.71(e) AUTHORIZATION
[0002] A portion of the disclosure of this patent document contains
material which is subject to copyright protection. The copyright
owner has no objection to the facsimile reproduction by anyone of
the patent document or the patent disclosure, as it appears in the
US Patent and Trademark Office patent file or records, but
otherwise reserves all copyright rights whatsoever.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0003] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX, IF ANY
[0004] Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0005] The present invention relates, generally, to thermal
ablation systems, apparatus and methods. Particularly, the
invention relates to a thermal ablation device and method for
treating abnormal tissue in the esophagus. Most particularly, the
invention relates to a device and method for use in treatments for
Barrett's Esophagus, Esophageal Adenocarcinoma, Esophageal Squamous
Cell Carcinoma, and the like.
2. Background Information
[0006] Barrett's esophagus is a condition in which tissue in the
esophagus (a tube connecting the mouth and stomach) is replaced by
tissue similar to the stomach lining. It is often diagnosed in
persons who have long term gastroesophageal reflux disease (GERD).
It is associated with an increased risk of developing esophageal
cancer. Treatment includes management of GERD, drug therapy, and
laser therapy. Treatment also includes balloon-based radio
frequency ablation.
[0007] Esophageal adenocarcinoma and Esophageal squamous cell
carcinoma are forms of esophageal cancer that occurs in the
esophagus. Treatment typically involves chemotherapy, radiation and
surgery.
[0008] Existing technology in this field is believed to have
significant limitations and shortcomings. For this and other
reasons, a need exists for the present invention.
[0009] US Patent Application 2012/0143180 (Lee et al.) discloses a
microwave antenna housed within a balloon for treatment of
Barrett's esophagus and to keep the antenna in the center of the
esophagus.
[0010] 2010/0168727 (Hancock et al.) discloses a balloon device for
delivery of microwave radiation to the esophagus.
[0011] U.S. Pat. No. 8,442,645 (Zelickson et al.) discloses a
balloon encapsulating an energy transmitting device for treatment
of esophageal tissue.
[0012] U.S. Pat. No. 7,530,979 (Ganz et al.) discloses a device
including a balloon member for application of microwave energy to
treat Barrett's esophagus.
[0013] U.S. Pat. No. 6,846,312 (Edwards et al.) discloses a GERD
treatment device having an expandable member with a microwave
energy source.
[0014] U.S. Pat. No. 6,238,392 (Long) discloses a bipolar electro
surgical device for treatment of Barrett's esophagus using RF
ablation and a balloon electrode.
[0015] U.S. Pat. No. 6,230,060 (Mawhinney) discloses a medical
device with a balloon structure enclosing a microwave antenna.
[0016] All US patents and patent applications, and all other
published documents mentioned anywhere in this application are
incorporated by reference in their entirety.
BRIEF SUMMARY OF THE INVENTION
[0017] The invention provides a thermal, esophageal ablation
apparatus and method which are safe and effective, and which are
believed to fulfill a need and to constitute an improvement over
the background technology.
[0018] In one aspect, the invention provides an microwave thermal
ablation system for human medical therapy, comprising:
[0019] a microwave generator;
[0020] at least one microwave emitter communicatively connected to
the microwave generator, the microwave emitter being adapted to
being inserted into the body of a patient;
[0021] a medical balloon inflation means; and
[0022] a positioning balloon connected to the balloon inflation
means and to the at least one microwave emitter for holding the at
least one microwave emitter in a desired position relative to a
target tissue or tissues within the body of a patient.
[0023] In another, narrower, aspect, the invention provides a
microwave thermal ablation system for use in treating Barrett's
Esophageal cells via non-contact dielectric heating,
comprising:
[0024] a. a microwave generator for providing preferably 17-18 GHz
microwave energy;
[0025] b. at least one microwave emitter communicatively connected
to the microwave generator, the microwave emitter being adapted to
being inserted into the body of a patient;
[0026] c. a medical balloon inflation means;
[0027] d. a positioning balloon connected to the balloon inflation
means and to the at least one microwave emitter for holding the at
least one microwave emitter in a desired position relative to a
target tissue or tissues within the body of a patient, the
positioning balloon being disposed around the at least one
microwave emitter; and
[0028] e. a catheter shaft including: [0029] (i) at least power
line electrically connecting the microwave generator and the at
least one microwave generator, and [0030] (ii) at least one lumen
communicatively fluidly connecting the balloon inflation means and
the positioning balloon, the at least one microwave emitter and the
positioning balloon being coupled to the catheter shaft at a
predetermined position, the catheter shaft being adapted to being
inserted into the body of a patient and for translating the at
least one microwave emitter and the positioning balloon within and
through the patient's body.
[0031] In a further aspect, the invention also provides a microwave
thermal ablation method for human medical therapy, comprising the
steps of:
[0032] a. providing a system including [0033] i. a microwave
generator; [0034] ii. at least one microwave emitter
communicatively connected to the microwave generator, the microwave
emitter being adapted to being inserted into the body of a patient;
[0035] iii. a medical balloon inflation means; [0036] iv. a
positioning balloon connected to the balloon inflation means and to
the at least one microwave emitter for holding the at least one
microwave emitter in a desired position relative to a target tissue
or tissues within the body of a patient; and [0037] v. wherein the
positioning balloon is disposed on a catheter having at least one
lumen for power connection between the microwave generator and the
at least one microwave emitter, and fluid communication between the
balloon inflation means and the positioning balloon;
[0038] b. inserting the catheter into a patient's body with the
balloon in an uninflated state,
[0039] c. moving the at least one microwave emitter and surrounding
positioning balloon to a desired position near target tissue that
is to be thermally ablated,
[0040] d. inflating the positioning balloon to a desired diameter,
thereby holding the at least one microwave emitter in a fixed
position near the target tissue by the positioning balloon, and
[0041] e. delivering microwave power from the microwave generator
to the at least one microwave for a predetermined period of time,
at a predetermined frequency and at a predetermined phase.
[0042] The aspects, features, advantages, benefits and objects of
the invention will become clear to those skilled in the art by
reference to the following description, claims and drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0043] FIG. 1 is a perspective view of a first embodiment of the
thermal ablation device of the present invention
[0044] FIG. 2 is a detailed view of a distal portion of the
device.
[0045] FIG. 3 is a crossectional view of a portion of the device
taken along line 3-3 of FIG. 2.
[0046] FIG. 4 is an illustration of the anatomy of a patient with
Barrett's' esophagus.
[0047] FIG. 5 is a schematic of an embodiment of the handset of
FIG. 1 with a microwave generator.
[0048] FIGS. 6A-C are proximal end, side elevation, and distal end
views, respectively, of a second embodiment of the thermal ablation
device, including a deployable antenna array with an inner
deployment balloon both shown in a deployed state.
[0049] FIGS. 6D-F are proximal end, side elevation, and distal end
views, respectively, of the embodiment shown in FIGS. 6A-C, with
surface shading.
[0050] FIGS. 7A-C are proximal end, side elevation, and distal end
views, respectively, of the embodiment of FIGS. 6A-F, including an
outer positioning balloon, also deployed, and in phantom to show
the relationship of internal elements.
[0051] FIG. 8 is an view, partially in phantom to reveal interior
elements, of a third embodiment of the thermal ablation device.
[0052] FIGS. 9A-C are proximal end, side elevation, and distal end
views, respectively of the device of FIG. 8, with another
embodiment of an antenna array and an inner deployment balloon,
showed deployed.
[0053] FIGS. 9D-F are views similar to those shown in FIGS. 9A-C,
with surface shading.
[0054] FIGS. 10A-C are proximal end, side elevation, and distal end
views, respectively, of the embodiment of FIGS. 9A-F, including an
outer positioning balloon, also deployed, and in phantom to show
the relationship of layered elements.
[0055] FIG. 11 is a side elevation view of a fourth embodiment of
the device of the invention, including a balloon in an expanded
state.
[0056] FIG. 12 is an elevation view of the device showing certain
internal components thereof in phantom in an expanded or actuated
state.
[0057] FIG. 13 is an isometric view of certain internal components
of the device in an actuated state.
[0058] FIG. 14 is an isometric view of the device showing the
device operatively disposed in the esophagus of a patient.
[0059] FIG. 15 is a side elevation view of the scaffolding assembly
and antennae of the device in a collapsed state.
[0060] FIG. 16 is an opposite side elevation view of the
scaffolding assembly.
[0061] FIG. 17 is an end view of the scaffolding assembly.
[0062] FIG. 18 is a side elevation view of the scaffolding assembly
and antennae of the device in an expanded state.
[0063] FIG. 19 is an opposite side elevation view of the
scaffolding assembly.
[0064] FIG. 20 is an end view of the scaffolding assembly.
[0065] FIG. 21 is a side elevation view of a fifth embodiment of
the device of the invention, including an external balloon in an
expanded state.
[0066] FIG. 22 is an elevation view of the device showing certain
internal components thereof in phantom, including an internal
balloon and antennae in an expanded or actuated state
[0067] FIG. 23 is an isometric view of the device showing the
device.
[0068] FIG. 24 is an isometric view of certain internal components
of the device.
[0069] FIG. 25 is a side elevation of an embodiment of the device
including the balloon assembly of FIGS. 21-24 and a handle
assembly.
[0070] FIG. 26 is a detailed view of the balloon assembly, with
internal components visible.
[0071] FIG. 27 is a detailed view of the handle assembly.
[0072] FIG. 28 is an isometric view of the system of FIG. 25.
[0073] FIG. 29 illustrates an embodiment of a generator assembly
useable with the system of the invention.
DETAILED DESCRIPTION
[0074] The present invention provides a system, device and method
for treating abnormal tissue in the esophagus. The invention is
useful for treating Barrett's esophagus, esophageal adenocarcinoma,
esophageal squamous cell carcinoma, and the like. The invention
functions, in general, via ablation and particularly thermal
ablation. The system preferably uses microwave power.
[0075] FIGS. 1-3 show a first embodiment of the esophageal ablation
system of the present invention. The system 10 comprises a handset
including an elongated, flexible shaft 11 and an emitter assembly
12 at the terminal, distal end of the shaft 11. The system
preferably includes a hand piece type positioner 13 which is
manipulated by a user to insert and steer the shaft 11 and emitter
assembly 12 into and through the mouth and esophagus of a patient.
The hand piece 13 has a connection end 14 for communicative mating
with fluid systems and power systems. The hand piece 13 also has a
distal end 15 from which the shaft 11 extends.
[0076] Referring also to FIGS. 2 and 3, the elongated, flexible
shaft 11 comprises a central power cable 20, which is preferably
coaxially surrounded by an inner layer 21 and an outer layer 22.
The power cable 20 conducts microwave power from a power generator
(shown in FIG. 5 and discussed below) to the emitter assembly 12.
An outer lumen 23 is formed between the outer layer 22 and the
inner layer 21, and permits inflow of fluids (air, gas, water or
other liquids) used to actuate an optional balloon. An inner lumen
24 formed between the inner layer 21 and the power cable 20 permits
outflow of fluids in embodiments where a balloon is used. Inflow
terminates at orifice 25. Outflow initiates at orifice 26. The
shaft 11 has a predetermined preferred length and outside diameter.
Flow is preferably reversible.
[0077] Referring to FIG. 2, the emitter assembly 12 comprises at
least one emitter antennae 30 which is communicatively connected to
the distal, terminal end of the power cable 20. The emitter
antennae emits microwave radiation to target tissues selected by
the user clinician. The emitter 30 is preferably a broadband
emitter capable of emitting a range of microwave frequencies and
phases. The emitter may alternatively be a narrow-band antenna.
Preferably, the antenna structurally is a coaxial antenna, patch
antenna or planar antenna array. It is within the purview of the
invention that the antenna may alternatively have a tri-axial,
slot, helical, bow-tie, dipole or a multi-array antennae structure.
The emitter may be positioned laterally, longitudinally or
rotationally via the shaft 11. Additionally, the emitter may be
moved in 3 dimensions during actuation. Energy may be emitted
circumferentially.
[0078] During microwave emission, the antennae 30 is preferably
spaced apart from the target tissue a predetermined distance. This
provides non-contact dielectric heating of the tissue. The balloon
40 is preferably used for such positioning. The balloon 40 is
inflated and deflated by fluid conducted to and from the inlet and
outlet lumens 23 and 24. The balloon 40 may be used to position the
emitter 30 centrally or off center in the esophagus relative to
target tissue. The balloon 40 may be compliant, non-compliant or
semi-compliant. In one embodiment, the balloon has a length of
10-60 mm, and a diameter of 14-40 mm. The balloon 40 is preferably
constructed of a transparent material to permit visualization of
positioning by the user via an endoscope or the like. Visualization
may be made before or during emitter actuation. The device
preferably has visual indicator to show target ablation zone. This
could be a marking on the outer balloon such as an outline of the
target ablation zone. Alternatively, it may take the form of an
optical cue such as an LED/laser projection on to target ablation
zone. Alternatively or additionally, the distance from the emitter
30 to the target tissue may be detected via microwave topography.
The balloon's surface may include one or more shielded areas that
permit or inhibit microwave transmission to control ablation.
Further, the shielding may be adjustable by the user during a
procedure.
[0079] In the embodiment shown the balloon 40 and emitter 30 are
fixed in position relative to each other. It is within the purview
of the invention that the position of the balloon 40 and emitter 30
may be varied and may be adjustable.
[0080] It is within the purview of the invention that multiple
emitters may be used with the system. And although the embodiment
of the system includes a balloon to position the emitter relative
to the target tissue, it is also within the purview of the
invention that other means of spacing may be used, including other
expandable/retractable devices or assemblies. Further, the position
of multiple emitters may be adjusted (rotationally. laterally and
longitudinally) relative to each other. And, the emitters may be
actuated independently from each other.
[0081] An alternative version of the embodiment discussed above,
the hand set 10 includes a temperature sensor such as a
thermocouple, thermistor, optical temperature sensor, or the like
to measure tissue temperature. Alternatively, tissue properties may
be measured via radiometric sensing using the emitter 30 as a
receiver.
[0082] Referring to FIG. 5, the handset 10 is connectable to a
microwave generator 16. The generator 16 may provides variable
frequency, phase and power duty cycle to modify the thermal profile
of the tissue and to control the depth of penetration of energy
into the tissue. In one embodiment, the generator 16 provides a
17-18 GHz frequency range. A gas supply 17 is also connected to the
handset 10. The gas supply may comprise a pump and/or a control
valve connected to source of gas. Alternatively, the gas supply 17
may be integrated with the generator 16.
[0083] FIGS. 6 and 7 show a second embodiment of the device 60 of
the invention with a compliant inner deployment balloon 62, an
antenna array 64 mounted there over and with fixed angular spacing,
and a compliant outer positioning balloon 66. The device 60 also
has a proximal shaft assembly 68 and a distal tip assembly 69. The
inner balloon 62 diameter may is controllable to fix or optimize
the distance between the antenna 64 and the ablation target. The
antenna array is rotatable from the handle to enable
circumferential ablation. The antenna 64 struts constrain the arc
length between adjacent antennas. This maintains the distance
between antennas thereby fixing the amount of overlap between
electric fields. The overlap is constant over a full diameter
range.
[0084] Alternatively, the antennas may also be constructed and
arranged in a linear array to cover a greater axial distance.
Lastly, it is within the purview of the invention that the device
60 could be constructed of a self expanding scaffold antenna array,
thereby obviating the inner balloon 62.
[0085] FIGS. 8-10 show a third embodiment of the device 70 of the
invention featuring planar scaffold guides 82. The device 70 has a
compliant inner deployment balloon 72, an array of four (4)
antennas 74 mounted there over and with fixed angular spacing, and
a compliant outer positioning balloon 76. The device 70 also has a
proximal shaft assembly 78 and a distal tip assembly 79. This
embodiment 70 has four antennas in a radial array. It is believed
to be optimal, however, from 2 to 12 antennas may be used to
practice the principles of the invention. Multiple antennas may be
activated at once. Or, a single antenna may activated to ablate a
narrow patch of target tissue.
[0086] This device 70 may also use a self expanding, or
mechanically expandable (controlled from the handle) antenna array.
However, the use of an inner balloon 72 is believed to be
advantageous because the inflation fluid can be controlled and the
dielectric properties of the fluid chosen for inflation modified to
control ablation. A linear array may also be used to cover a
greater axial surface in certain circumstances.
[0087] Referring to FIGS. 11-14, a fourth embodiment of the device
100 comprising a balloon 112 attached proximally to an outer shaft
114 and distally to a tip 116 with a thru lumen 118. The balloon
112 is preferably constructed of urethane. The balloon 112 is shown
in an expanded state. It can expand to accommodate the full range
of esophagi lumen diameters. The urethane balloon 112 is preferably
inflated with air. The function of the urethane balloon 112 and
outer shaft 114 is to create a deterministic circular lumen of
known diameter inside the esophagus of a patient. The outer shaft
114 is connected to a handle and allows for the insertion of the
entire assembly 110 down the mouth of the patient to the target in
the esophagus. Exemplary handles embodiments are shown in FIGS. 1,
25 and 28.
[0088] As is best shown in FIGS. 12-14, inside the balloon 112 and
outer shaft 114 is an inner shaft 120. The inner shaft 120 contains
a coaxial cable 122 and a pull wire 124. The coaxial cable 122
connects to an antenna or emitter 130. The connection is preferably
a solder connection. The microwave antenna 130 is preferably a
direct fed, patch type antenna that is curved around a radius.
Applicants have found that curving provides mechanical advantages,
and also increases the ablation zone. The antenna 130 is designed
to operate preferably between 17-18 GHz. The antenna 130 and
coaxial cable 122 assembly is soldered to an antenna mount 132.
Referring also to FIGS. 15-20, the antenna mount 132 connects to a
scaffold assembly via expansion links 136 A and B. The antenna
mount 132 also serves as a transition from the coaxial cable 122 to
the antenna 130. This arrangement maximizes energy transfer from
the cable 122 to the antenna 130 and reduces reflected power. The
expansion links 136 attach to a centering/bottom link 138 and a
pull link 140. The pull link 140 further connects to a pull wire
142 or mandrel. The pull wire 142 connects to a mechanism in the
handle that creates the expansion and contraction of the scaffold
assembly 134 arid allows the user to position the antenna 130 at
the correct offset from the tissue which will result in the most
efficient heating of the target tissues.
[0089] The bottom/centering link 138 keeps the entire antenna
assembly 130 on centerline. A telescoping shaft 144 inserts into
the through lumen 118 of the outer balloon tip 116. This allows the
user to rotate the antenna assembly 360.degree. for circumferential
ablations and also traverse the antenna assembly 130 longitudinally
along the axis of the esophagus so that the user can perform
ablations along the length of the esophagus.
[0090] It is within the purview of the invention that all
mechanical movements (rotation, scaffold expansion/contraction,
longitudinal movement) can be automated through the use of motors
(not shown).
[0091] The most preferred frequency range of 17-18 GHz limits the
depth of penetration of the ablation zone to the first 1.5 mm of
tissue, which is desired for treatment of Barrett's Esophagus.
Modulating input power and dwell time can further control depth of
ablation.
[0092] Referring to FIGS. 21-23, a fifth embodiment of a device 200
of the invention comprises a balloon 212 connected proximally to an
outer shaft 214 and distally to a tip 218 assembly. This balloon
212 is also preferably constructed of urethane. The functions of
these elements are substantially the same the same as similar
structures in the previous embodiment of FIGS. 11-20.
[0093] Inside the outer balloon 212 and outer shaft 214 is an inner
shaft 218, which consists of two lumens. A coaxial cable 222
extends through the first lumen. The second lumen is used to push
saline through to inflate the balloon 212. The coaxial cable 222
emerges through the inner shaft 218 and attaches to an antenna 230.
The antenna 230 preferably has the same structure and function as
the antenna described and shown in the previous embodiment of FIGS.
11-20. The antenna 230 and coaxial cable 222 assembly once again is
attached to an antenna mount 232, which serves the same purpose of
efficiently transferring energy from the cable 222 to the antenna
230.
[0094] Referring also to FIG. 24, attached to the distal end of the
inner shaft 218 is an inner, semi-compliant balloon 240. The inner
balloon 240 is capable of multiple diametrical positions over a
total diameter range increase of 1 mm-5 mm growth. The antenna
mount 233 is also attached to the balloon 240. The inner balloon
240 replaces the mechanical scaffold from the previous embodiment.
The balloon 240 is inflated with saline, and depending on the input
pressure of the fluid, it will expand to a deterministic diameter.
This permits the user to deliver the antenna 230 to the correct
offset from the target tissue.
[0095] The semi-compliant balloon 240 is distally attached to the
telescoping tip/shaft 250. The telescoping shaft 250 inserts into
the through lumen 224 of the outer balloon tip 216. This allows the
user to rotate the antenna assembly 230 360.degree. for
circumferential ablations and also traverse the antenna assembly
230 longitudinally along the axis of the esophagus so that the user
can perform ablations along the length of the esophagus.
[0096] Once again, all the mechanical actions can be adapted to be
fully automated. Motors can rotate and longitudinally move the
inner shaft assembly. Further, an automated pump can be constructed
and arranged inflate the inner, semi-compliant balloon 240 with
saline to the correct diameter.
[0097] FIGS. 25-28 show an embodiment of the system 300 including
the emitter assembly 200 described above with an alternative
embodiment of a handle assembly 310. The handle assembly 310
includes a handle body 312 with a cavity in which is disposed a
thumb wheel 320 for rotating the inner balloon 240 of the emitter
200. The thumb wheel 320 is connected at one end to an SMC push to
connect rotary fitting 322. A rotating connector is disposed at the
opposite end of the thumb wheel 320 for connection to an antenna
power cable. A ball screw 316 provides precise longitudinal
movement. The handle body 312 preferably has ergonomic grooves to
facilitate optimal manual manipulation by the user.
[0098] FIG. 29 shows an embodiment of a control assembly 400. The
control assembly 400 comprises a power supply 402 communicatively
connected to a controller 408 containing control electronics. A
pump 404 and microwave power amplifier 406 are communicatively
connected to the controller 408. The pump 404 delivers fluid (such
as Saline) or gas (such as air) for hydraulic or pneumatic control
of the balloons of the emitter assembly 200. The amplifier 406
powers the antenna of the emitter 200. The amplifier 406 operates
in a frequency range of 915 MHz to 20 GHz. Preferred operating
frequencies are 2.45 GHz, 5 GHz and 17-18 GHz. Presently, the most
preferred frequency is approximately 18 GHz. Hydraulics, pneumatics
and microwave power are provided via a wiring harness 414
containing applicable coaxial cable, wiring and tubing, preferably
via a system handle 13 or 310 discussed above. User interface
controls such as an LCD Touch Screen monitor and input 410 and/or a
foot activated switch 412 are preferably communicatively connected
to the controller 408.
[0099] The embodiments above are chosen, described and illustrated
so that persons skilled in the art will be able to understand the
invention and the manner and process of making and using it. The
descriptions and the accompanying drawings should be interpreted in
the illustrative and not the exhaustive or limited sense. The
invention is not intended to be limited to the exact forms
disclosed. While the application attempts to disclose all of the
embodiments of the invention that are reasonably foreseeable, there
may be unforeseeable insubstantial modifications that remain as
equivalents. It should be understood by persons skilled in the art
that there may be other embodiments than those disclosed which fall
within the scope of the invention as defined by the claims. Where a
claim, if any, is expressed as a means or step for performing a
specified function it is intended that such claim be construed to
cover the corresponding structure, material, or acts described in
the specification and equivalents thereof, including both
structural equivalents and equivalent structures, material-based
equivalents and equivalent materials, and act-based equivalents and
equivalent acts.
* * * * *