U.S. patent application number 16/055769 was filed with the patent office on 2018-12-06 for system and method for variable depth ultrasound treatment.
The applicant listed for this patent is Guided Therapy Systems, LLC. Invention is credited to Peter G. Barthe, Michael H. Slayton.
Application Number | 20180345045 16/055769 |
Document ID | / |
Family ID | 35517513 |
Filed Date | 2018-12-06 |
United States Patent
Application |
20180345045 |
Kind Code |
A1 |
Barthe; Peter G. ; et
al. |
December 6, 2018 |
System and Method for Variable Depth Ultrasound Treatment
Abstract
A non-invasive variable depth ultrasound treatment method and
system comprises a variable depth transducer system configured far
providing ultrasound treatment to a patient. An exemplary variable
depth transducer system can comprise a transducer configured to
provide treatment to more than one region of interest, such as
between a deep treatment region of interest and a superficial
region of interest and/or a subcutaneous region of interest. The
variable depth transducer can comprise a transduction element
having a piezoelectrically active layer, matching layers and/or
other materials for generating radiation or acoustical energy. The
variable depth transducer may be configured to operate at moderate
frequencies within the range from approximately 750 kHz to 20 MHz
or more. In addition, the transduction element may be configured
with a variable depth device comprising one or more materials
configured to allow for control and focusing/defocusing of the
acoustic energy to more than one region of interest.
Inventors: |
Barthe; Peter G.; (Phoenix,
AZ) ; Slayton; Michael H.; (Tempe, AZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Guided Therapy Systems, LLC |
Mesa |
AZ |
US |
|
|
Family ID: |
35517513 |
Appl. No.: |
16/055769 |
Filed: |
August 6, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14264732 |
Apr 29, 2014 |
10039938 |
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16055769 |
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12834754 |
Jul 12, 2010 |
8708935 |
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14264732 |
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10944500 |
Sep 16, 2004 |
7824348 |
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12834754 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61N 7/00 20130101; A61N
2007/0069 20130101; A61N 2007/0065 20130101; A61N 2007/0073
20130101; A61B 34/30 20160201; A61B 2017/22028 20130101; A61N
2007/0095 20130101; A61B 2017/22024 20130101 |
International
Class: |
A61N 7/00 20060101
A61N007/00 |
Claims
1. A non-invasive ultrasound treatment system for providing
treatment to a patient, the system comprising: a variable depth
transducer system comprising: a transducer having a surface and
comprising at least one transduction element, and a variable depth
element comprising a reflective surface, wherein: the variable
depth transducer system operable to provide treatment to a region
of interest between a superficial and subcutaneous region of a
patient, and the reflective surface is configured to be inclined at
any angle with respect to the transducer such that energy emitted
by the surface of the transducer is bent, redirected or reflected
from the reflective surface towards the region of interest; wherein
the variable depth transducer comprises a spatial operable to
change the angle of inclination of the reflective surface to focus
the energy emitted by the surface of the transducer to any depth in
the region of interest; and a controller in communication with the
transducer and the variable depth element, the controller
comprising a control of the spatial control and a control of a
frequency of the energy.
2. The non-invasive ultrasound treatment system according to claim
1, wherein the variable depth transducer is configured for variable
control of the energy to change a depth location for lesion created
with the region of interest.
3. The non-invasive ultrasound treatment system according to claim
1, further comprising a coupling system configured for acoustic
coupling between the variable depth transducer system and the
region of interest.
4. The non-invasive ultrasound treatment system according to claim
3, wherein the coupling system is configured for temperature
control a the transducer to facilitate adjustment of a focal depth
of the energy emitted by the surface of the transducer.
5. The non-invasive ultrasound treatment system according to claim
1, further comprising a mechanical scanning device configured to
move the variable depth transducer system in at least one of a
translational movement and a rotational movement.
6. The non-invasive ultrasound treatment system according to claim
1, wherein the variable depth transducer system is configured to
image the region of interest.
7. The non-invasive ultrasound treatment system according to claim
1, wherein the frequency of the energy is in a range of 750 kHz to
20 MHz.
8. The no ultrasound treatment system according to claim 1, wherein
the frequency of the energy is in a range of 750 kHz to 8 MHz.
9. The non-invasive ultrasound treatment system according to claim
1, wherein the frequency of the energy is in a range of 8 MHz to 20
MHz.
10. The non-invasive ultrasound treatment system according to claim
1, wherein the transducer is coupled to the variable depth element
and is configured to focus the energy emitted by the surface of the
transducer to any depth in more than one region of interest.
11. The non-invasive ultrasound treatment system according to claim
1, wherein the reflective surface comprises at least one
mirror.
12. The non-invasive ultrasound treatment system according to claim
11, wherein the mirror is substantially flat in shape.
13. The non-invasive ultrasound treatment system according to claim
11, wherein the mirror is curved in shape.
14. The non-invasive ultrasound treatment system according to claim
1, wherein the transducer is configured with spatial control to
change at least one of a distance from the transducer to the
reflective surface, and an angle of the energy delivered into the
region of interest.
15. The non-invasive ultrasound treatment system according to claim
1, wherein the transducer is configured in a curved manner.
16. The non-invasive ultrasound treatment system according to claim
1, wherein the at least one transduction element is a plurality of
transduction elements configured to be activated by a plurality a
frequencies separated by at least one phase delay.
17. The non-invasive ultrasound treatment system according to claim
1, wherein the controller further comprises a display unit for
displaying at least one of imaging information, positional
information, and temperature information of a treatment region.
18. The non-invasive ultrasound treatment system according to claim
1, wherein the controller farther comprises a robotic arm
arrangement for controlling movement of the variable depth
transducer system.
19. The non-invasive ultrasound treatment system according to claim
18, wherein the controlling movement of the variable depth
transducer system is configured to create a plurality of lesions at
varying depths in the region of interest.
20. The non-invasive ultrasound treatment system according to claim
1, wherein the energy is focused to a first depth in the
superficial region and the energy is focused to a second depth in
the subcutaneous region, wherein the first depth and the second
depth is in a range from 0 mm to 5 cm, and the first depth is less
than the second depth.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/834,754 entitled "SYSTEM AND METHOD FOR
VARIABLE DEPTH ULTRASOUND TREATMENT" filed on Jul. 12, 2010, issued
as U.S. Pat. No. 8,708,935 on Apr. 29, 2014; which is a
continuation of U.S. patent application Ser. No. 10/944,500
entitled "SYSTEM AND METHOD FOR VARIABLE DEPTH ULTRASOUND
TREATMENT" filed on Sep. 16, 2004, issued as U.S. Pat. No.
7,824,348 on Nov. 2, 2010, all of which are incorporated herein by
reference.
FIELD OF INVENTION
[0002] This invention generally relates to an ultrasound system,
and more particularly, to a method and system for variable depth
ultrasound treatment.
BACKGROUND OF THE INVENTION
[0003] Many conventional applications of therapeutic ultrasound
have employed low frequency transducers. These transducers have
operational frequencies that typically range from 500 kHz to 1.5
MHz. Such low frequency transducers are often preferred because
they allow for acoustical energy to he focused deep into the body,
without harming the overlying tissue structures.
[0004] A conventional application of non-invasive therapeutic
ultrasound using a low frequency transducer is depicted in FIG. 1.
A conventional therapeutic system 100 comprises a transducer 102
that uses low frequency energy to treat a deep treatment region
110. Deep treatment region 110 is located at a deep depth 106 below
a superficial region 112, e.g., tissue layers and structures, and a
subcutaneous region 114 of a patient. Deep depth 106 may range from
several millimeters to 5-7 centimeters or more. Conventional system
100 cannot treat superficial regions 112 or subcutaneous regions
114 through use of low-frequency transducer 102, thus limiting the
applications of such systems. For example, some cosmetic surgeries
may also need to provide treatment to superficial and/or
subcutaneous, as well as deep treatment regions, thus eliminating
the use of lower frequency transducers.
[0005] Another undesirable side effect of low-frequency therapy is
that the acoustic energy must pass through intervening tissue
layers before reaching the desired deep treatment area. The
intervening layers tend to defocus the rays and absorb some of the
acoustic energy. This causes the focal spot size to widen, making
it difficult in control the location of the focal spot.
SUMMARY OF THE INVENTION
[0006] In accordance with various aspects of the present invention,
a variable depth ultrasound treatment method and system are
provided. An exemplary method and system comprise a variable depth
transducer system configured for providing ultrasound treatment to
more than one region of interest, such as between at least two of a
deep treatment region of interest, a superficial region of
interest, and/or a subcutaneous region of interest.
[0007] In accordance with various exemplary embodiments, a variable
depth transducer system can be configured for spatial control, as
by changing the distance from an exemplary transducer to a
reflecting surface, of changing the angles of energy focused or
unfocused to the region of interest, and/or configured for temporal
control, such as by controlling changes in the frequency, drive
amplitude and timing of the exemplary transducer. As a result,
changes in the location of the treatment region, the shape and size
and/or volume of the spot or region of interest, as well as the
thermal conditions, can be dynamically controlled versus time.
[0008] In accordance with an exemplary embodiment of the present
invention, the variable depth transducer can comprise a
transduction element having a piezoelectrically active layer,
matching layers and/or other materials for generating radiation or
acoustical energy. The variable depth transducer may be configured
to operate at moderate frequencies to provide variable depth
treatment. For example, an exemplary variable depth transducer
system can be configured for providing treatment to a superficial
region of interest, and/or to a subcutaneous region of interest
utilizing moderate frequencies below 20 MHz, such as within a range
from approximately 750 kHz to 20 MHz, or higher frequencies of 35
MHz or more.
[0009] In accordance with another exemplary embodiment of the
present invention, the transduction element may be configured with
a variable depth element comprising one or more materials
configured to allow for control and focusing/defocusing of the
acoustic energy to more than one region of interest, such as
between a deep treatment region of interest and a superficial
region of interest, and/or a subcutaneous region of interest. The
materials utilized for the variable depth element for control and
focusing/defocusing may be configured in a variety of manners and
shapes, such as substantially flat, curved, or other arrangements
for bending, reflecting and/or redirecting radiation and acoustical
energy. In addition, the variable depth element be configured
within, or comprise a device coupled to, the transduction element
in a variety of manners to provide for focusing/defocusing and
control of the treatment energy.
[0010] In accordance with another exemplary embodiment of the
present invention, an exemplary transducer may be configured to
enable energy deposition not only proximate a fundamental frequency
of a piezoelectric material within the transduction element, but
also at harmonic frequencies of the material, above a fundamental
frequency, as well as resonances below a fundamental frequency.
These multiple resonances may be controlled and enabled through
various focusing techniques and transducer structures, including
the adding of matching layers and/or backing layers to shape the
resonant characteristics of the transducer.
[0011] In accordance with another exemplary embodiment of the
present invention, a variable depth acoustic transducer can also be
configured for generating high acoustic power for treatment
purposes, while also providing for good imaging capabilities. For
example, to allow for the treatment spot size to be optimally
controlled at various treatment depths an exemplary embodiment of
the present invention may comprise a transducer configured into an
array of sub-elements, each sub-element configured for processing
acoustic waves with a sufficient bandwidth for good axial
resolution.
[0012] In accordance with another exemplary embodiment of the
present invention, a variable depth transducer may be configured in
a probe arrangement to provide treatment. The variable depth
transducer may also be configured with various mechanical devices
to allow for optimal treatment and therapy, for example to provide
controlled positioning of the variable depth transducer, such as
through a non-invasive configuration. Further, the variable depth
transducer may also be configured for one-dimensional,
two-dimensional and annular arrays, and/or for three-dimensional
treatment applications.
[0013] In accordance with another aspect of the present invention,
an exemplary variable depth treatment system and method may also be
configured to provide therapeutic heating, cooling and/or imaging
of a treatment region as well as acoustically monitoring the
temperature profile or other tissue parameter monitoring of the
treatment region and the general vicinity thereof. For example, in
accordance with an exemplary embodiment, an exemplary variable
depth system may be configured with a dynamic feedback arrangement
based on monitoring of temperature or other tissue parameters,
and/or based on imaging information to suitably adjust the spatial
and/or temporal characteristics of the variable depth
transducer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The subject matter of the invention is particularly pointed
out and distinctly claimed in the concluding portion of the
specification. The invention, however, both as to organization and
method of operation, may best be understood by reference to the
following description taken in conjunction with the claims and the
accompanying drawing figures, in which like parts may be referred
to by like numerals:
[0015] FIG. 1 illustrates a diagram of treatment using a prior art
ultrasound treatment system;
[0016] FIG. 2 illustrates a block diagram of an ultrasound
treatment system in accordance with an exemplary embodiment of the
present invention;
[0017] FIG. 3 illustrates a block diagram of a variable depth
ultrasound treatment system in accordance with an exemplary
embodiment of the present invention;
[0018] FIG. 4 illustrates a diagram of a variable depth ultrasound
treatment system in accordance with an exemplary embodiment of the
present invention;
[0019] FIGS. 5A and 5B illustrate exemplary embodiments for
variable depth ultrasound transducers for treatment in accordance
with the present invention;
[0020] FIG. 6 illustrates another exemplary embodiment for a
variable depth ultrasound transducer for treatment in accordance
with the present invention;
[0021] FIG. 7 illustrates an exemplary embodiment for electronic
focusing of a transducer in accordance with the present
invention;
[0022] FIG. 8 illustrates an exemplary diagram of treatment
characteristics of an exemplary transducer operating at the
fundamental frequency and other frequencies and/or resonances above
and below the fundamental in accordance with the present
invention;
[0023] FIG. 9 illustrates an exemplary embodiment of a
two-dimensional array in accordance with the present invention;
[0024] FIG. 10 illustrates an exemplary embodiment of a probe
format for treatment in accordance with the present invention;
[0025] FIG. 11 illustrates an exemplary embodiment of a mechanism
for treatment in accordance with the present invention; and
[0026] FIGS. 12A and 12B illustrate an exemplary embodiment of an
annular array in accordance with the present invention.
DETAILED DESCRIPTION
[0027] The present invention may be described herein in terms of
various components and processing steps, it should be appreciated
that such components and steps may be realized by any number of
hardware components configured to perform the specified functions.
For example, the present invention may employ various medical
treatment devices, visual imaging and display devices, input
terminals and the like, which may carry out variety of functions
under the control of one or more control systems or other control
devices. In addition, the present invention may be practiced in any
number of medical or treatment contexts, and the exemplary
embodiments relating to a variable depth ultrasound treatment as
described herein are merely a few of the exemplary applications for
the invention. For example, the principles, features and methods
discussed may be applied to any medical or other tissue or
treatment application.
[0028] It accordance with various aspects of the present invention,
a non-invasive variable depth ultrasound treatment method and
system are provided. An exemplary method and system comprise a
variable depth acoustic transducer system configured for providing
ultrasound treatment to more than one region of interest in a
patient. For example, with reference to an exemplary embodiment
illustrated in a block diagram of FIG. 2, an exemplary system 200
for ultrasound treatment includes a variable depth transducer
system 202 that provides treatment to a region of interest 210.
Variable depth transducer system 202 may comprise a transducer 204
configured with a variable depth device 206. In providing
treatment, variable depth ultrasound system 202 may provide
therapy, imaging and/or temperature or other tissue parameter
monitoring to region of interest 210. Region of interest 210 can
comprise a deep treatment region, a superficial region, and/or a
subcutaneous region of interest or any other region of interest
located within a patient. To facilitate coupling of variable depth
ultrasound system 202 to region of interest 210, variable depth
ultrasound system 202 can further comprise a coupling system 208
configured for acoustic coupling ultrasound energy and signals.
[0029] An exemplary variable depth transducer system 300 is further
exemplified in a block illustrated in FIG. 3. Variable depth
transducer system 300 may comprise a control system 304, a
transducer 302, a variable depth element 306, and a coupling system
308. Control system 304 is configured for control and operation of
transducer 302 to provide treatment to more than one region of
interest. Transducer 302 and variable depth device 306 are
configured to provide variable depth ultrasound treatment to a
treatment region. Coupling system 308 is configured for coupling of
transducer 302 and variable depth device 306 to a region of
interest.
[0030] Control system 304 may be configured for use within an
ultrasound therapy system, an ultrasound imaging system, and/or an
ultrasound imaging, therapy and/or treatment monitoring system,
including motion control subsystem. In accordance with an exemplary
embodiment, a control system 304 may comprise a processor, a
display, and/or one or more input devices. The processor may
comprise a personal computer, a Unix system, or any other
conventional processing unit. The display may comprise a monitor,
LCD screen, or any other device configured to display an image. An
input/output device may comprise a keyboard, a mouse, a
touch-screen, or any other device for inputting information. The
information from the input device and images displayed may be
received or transmitted in any format, such as manually, by analog
device digital device, and/or by any other mechanisms. The
processor, display, and/or input device may be coupled together in
any manner. By coupling, the devices comprising control system 304
may be directly connected to each other or may be connected through
one or more other devices or components that allow a signal to
travel to/from one component to another. The various coupling
components for the devices comprising control system 304 can
include but are not limited to the internet, a wireless network, a
conventional wire cable, an optical cable or connection through any
other medium that conducts signals, and any other coupling device
or communication medium.
[0031] Coupling system 308 configured for the coupling ultrasound
energy and signals between transducer 302 and variable depth device
306 and a region of interest. Coupling system 308 may facilitate
such coupling through use of various coupling mediums, including
air and other gases, water and other fluids, gels, solids, and/or
any combination thereof, or any other medium that allows for
signals to be transmitted between transducer 302/variable depth
device 306 and the region of interest. In addition to providing a
coupling function, in accordance with an exemplary embodiment,
coupling system 308 can also be configured for providing
temperature control during the treatment application. For example,
coupling system 308 can be configured for controlled cooling of an
interface surface or region between transducer 302/variable depth
device 306 and the region of interest by suitably controlling the
temperature of the coupling medium. The suitable temperature for
such coupling medium can be achieved in various manners, and
utilize various feedback systems, such as thermocouples,
thermistors or any other device or system configured for
temperature measurement of a coupling medium. Such controlled
cooling can be configured to further facilitate spatial control of
variable depth transducer system 300.
[0032] Exemplary variable depth transducer 302 can be configured in
various manners. For example, a variable depth transducer system
can be configured for spatial control, such as by controlled
changing of the distance from an exemplary transducer to a
reflecting surface, or controlled changing of the angles of energy
focused or unfocused to the region of interest, e.g., variable
depth transducer 302 can be configured with variable depth element
306 comprising a frequency dependent lens configured for control of
focal depth and position by changing the frequency of excitation of
variable depth transducer 302. In addition, variable depth
transducer 302 can also be configured for temporal control, such as
by controlling changes in the frequency, drive amplitude and timing
of the exemplary transducer. Thus, an exemplary variable depth
transducer can be configured with spatial and/or temporal control.
As a result, changes in the location of the treatment region, the
shape and size and/or volume of the spot or region of interest, as
well as the thermal conditions, can be dynamically controlled
versus time.
[0033] Variable depth element 306 can be suitably coupled to
transducer 302 to facilitate variable depth treatment. By coupling,
transducer 302 may be directly and/or movably connected to variable
depth device 306, or may be connected through one or more various
components or elements that enable energy and/or signals to travel
to/from one component to another. Transducer 302 and variable depth
element 306 may also be combined into a single device, wherein
variable depth device 306 is configured within transducer 302,
e.g., as a part of a transduction element of transducer 302.
[0034] Variable depth element 306 is configured to enable variable
depth treatment system 300 to provide treatment to more than one
region of interest, such as between a deep treatment region of
interest, a superficial region of interest, and/or a subcutaneous
region of interest, or other regions in between. Such treatment can
occur within a single region of interest, or within more than one
region of interest, at the same time. For example, with momentary
reference to FIG. 4 an exemplary embodiment of a variable depth
treatment system 400 is shown. Variable depth treatment system 400
may be configured for operating within moderate frequencies ranging
from approximately 750 kHz to 20 MHz or more. Variable depth
treatment system 400 may be configured with a variable depth
transducer system 402 comprising a transducer configured with a
variable depth device. Variable depth transducer system 402 may be
coupled to a control system for receiving and transmitting signals
to/from a region of interest.
[0035] During operation, variable depth transducer system 402 may
be configured to transmit or receive signals to treat a deep
treatment region 410 located at deep depth 406 within a patient.
For example, depth 406 for deep treatment region 420 may range from
approximately 50 mm to 7 cm or more:
[0036] Variable depth transducer system 402 may also be configured
to treat a second inner region 422 of a patient. Inner region 422
may comprise a superficial layer 412 of a patient and/or a
subcutaneous layer 414 of patient. Inner region 422 is located at a
shorter depth 420 within tissue layers of a patient. For example,
depth 420 may range from approximately 0 mm to 5 cm or more within
a patient, wherein the 0 mm range comprises the outer surface of
superficial layer 412 of the patient. In other words, superficial
layer 412 of the patient may comprise any area on or near the
surface of the patient. Treatment by variable depth treatment
system 400 may include treatment of both deep region 410 and inner
region 422, or within only one region of interest.
[0037] Variable depth element 306 can be configured in various
manners to facilitate treatment of more than one region of
interest, such as inner region 422 and/or deep-seated region 410.
In accordance with an exemplary embodiment of the present
invention, transducer 302 may be configured with variable depth
element 306 comprising one or more materials configured to allow
for control and focusing refocusing of the acoustic energy to more
than one region of interest. For example, with reference to
exemplary embodiments illustrated in FIGS. 5A and 5B, a variable
depth transducer system 500 can comprise a transducer 502,
electrical leads 510, and a variable depth device 528 or 530
suitably configured with transducer 502 to facilitate
treatment.
[0038] Transducer 502 can include a transduction element comprising
a piezoelectrically active material, such as lead zirconante
titanate (PZT), or any other piezoelectrically active material,
such as a piezoelectric ceramic, crystal, plastic, and/or composite
materials, as well as lithium niobate, lead titanate, barium
titanate, and/or lead metaniobate. In addition to or instead of a
piezoelectrically active material, variable depth transducer 502
may comprise any other materials configured for generating
radiation and/or acoustical energy. Variable depth transducer 502
may also comprise one or more matching layers and/or backing layers
to suitably shape the resonant character of transducer 502. For
example, variable depth transducer 502 may be configured, along
with transduction element, with one or more matching layers and/or
backing layers coupled to a piezoelectrically active material or
any other material configured for generating radiation and/or
acoustical energy.
[0039] For temporal control, the thickness of the transduction
element of variable depth transducer 502 may be selected to provide
a center operating frequency of moderate range, for example from
approximately 750 kHz to 30 MHz or more. Lower frequencies, e.g.,
between approximately 750 kHz and 8 MHz, can facilitate deeper
penetration and higher frequencies, e.g., between approximately 8
to 20 MHz or more, can facilitate greater resolution. Selecting the
frequency for operation can be based on the degree and balance of
energy penetration and resolution that is desired for an
application.
[0040] Electrical leads 510 may be configured to enable power to be
transmitted to and signals received from variable depth transducer
502, and can comprise any wiring type, configuration and
arrangement for use with ultrasound transducers. Variable depth
transducer 502 may also be coupled to electrical leads 510 in
various manners. For example, while FIG. 5 depicts electrical leads
510 coupled to only one end of variable depth transducer 502,
electrical leads 510 may also be coupled together on an opposite
end, or any other location along variable depth transducer 502.
[0041] To facilitate spatial control, in an exemplary embodiment,
variable depth device 528 can comprise one or more reflective
materials 504 configured to provide control and focusing of
acoustic or radiation energy from variable depth transducer 502
towards a region of interest 518. In accordance with an exemplary
embodiment, reflective materials 504 can comprise acoustic mirrors,
lenses, reflectors or prisms configured may focusing of acoustic or
radiation energy. The exemplary mirrors, reflectors or prisms may
comprise any material for reflecting, bending or redirecting
acoustic or radiated energy. For example, such materials may
include stainless steel, aluminum, or any other metal alloy, glass,
plastic, or any other material capable of bending, redirecting
and/or reflecting back acoustical energy from a surface to another
direction.
[0042] In accordance with one exemplary embodiment, reflective
materials 504 may be suitably inclined at approximately a 45 degree
angle with respect to variable depth transducer 502; however,
reflective materials 504 may be configured to be inclined at any
angle with respect to variable depth transducer 502 such that
energy transmitted from variable depth transducer 502 is bent,
redirected or reflected from reflective materials 504 towards a
region of interest 518. Changing the angle of inclination can
suitably control the focusing of acoustic energy to any one region
of interest 518, such as to a deep treatment region of interest, a
superficial region of interest, or a subcutaneous region of
interest.
[0043] Variable depth devices 528 and 530 may be configured in a
variety of manners, such as substantially flat, curved, or other
suitable arrangements for reflecting, bending or redirecting
acoustic or radiated energy. For example, with reference to FIG. 5A
variable depth device 528 can comprise mirrors 504 configured in a
substantially flat manner. However, with reference to FIG. 5B,
variable depth device 530 can also comprise mirrors 506 configured
in a curved arrangement to allow for focusing of energy from
variable depth transducer 502 to a region of interest 520. While
FIG. 5B illustrates mirrors 506 as substantially spherical and
symmetric, mirrors 506 may also be curved in an aspherical and/or
asymmetric manner such that energy transmitted from variable depth
transducer 502 is bent, redirected, or reflected from mirrors 506
towards a region of interest 520. Still further, mirrors 506 can
also be configured in other shapes and arrangements, such as
jagged, saw tooth, wavy or other non-planar surfaces, or any other
surface or compound surfaces configured for reflecting, bending or
redirecting acoustic or radiated energy.
[0044] Moreover, while FIG. 5A depicts variable depth device 528
with mirrors 504 configured to be substantially flat, and FIG. 5B
depicts variable depth device 530 with mirrors 506 configured to be
curved, variable depth devices 528, 530 may also be configured with
any combination of substantially flat, curved mirrors, and/or other
planar, non-planar or other arrangements for facilitating spatial
control. In accordance with an exemplary embodiment utilizing
spatial and temporal control, variable depth devices 528 and 530
can be configured with a frequency dependent mirror or lens
configured for spatial control of the focal depth and position by
changing the frequency of excitation of variable depth transducer
502.
[0045] As a result, an exemplary transducer system 500 can be
configured for providing treatment to a superficial region of
interest and/or to a subcutaneous region of interest utilizing
moderate frequencies below approximately 20 MHz. For example, an
exemplary transducer system 500 can provide treatment to
superficial regions and/or to subcutaneous regions that are more
commonly addressed in cosmetic applications with an operating
frequency range from approximately 750 kHz to 35 MHz or more.
[0046] Variable depth transducer system 500 can be configured in
various arrangements to provide non-invasive treatment. For
example, in accordance with an exemplary embodiment, variable depth
devices 528, 530 may be configured with variable depth transducer
502 within a housing 536. Housing 536 can comprise any
configuration of transducer housing for containing transducers and
for interfacing with a patient to allow treatment, such as
facilitate non-invasive treatment. Coupling of signals from
transducer 502 and variable depth devices 528, 530 through housing
536 to a region of interest may be facilitated through any coupling
medium, such as air and other gases, water and other fluids, gels,
solids, any combination thereof, and/or any other medium that
allows for signals to be transmitted from transducer 502/variable
depth devices 528, 530 to is region of interest.
[0047] In addition to comprising separate devices and components,
variable depth transducer 302 and variable depth element 306 may
also comprise the same device, i.e., variable depth element 305 is
configured within transducer 302. For example, with reference to an
exemplary embodiment illustrated in FIG. 6, a variable depth
transducer system 600 can comprise a variable depth transducer 602
configured as a variable depth device to provide for control and
focusing acoustic energy 620 towards a region of interest 630.
[0048] Variable depth transducer 602 may comprise a transduction
element comprised of a piezoelectrically active material, such as
lead zirconante titanate (PZT), or any other piezoelectrically
active material, such as a piezoelectric ceramic, crystal, plastic,
and/or composite materials, as well as lithium niobate, lead
titanate, barium titante, and/or lead metaniobate. Variable depth
transducer 602 may also comprise one or more matching and/or
backing layers configured along with the piezoelectrically active
material. In addition to or instead of a piezoelectrically active
material, variable depth transducer 602 may comprise any other
materials configured for generating radiation and/or acoustical
energy.
[0049] In accordance with an exemplary embodiment, variable depth
transducer 602 is configured in a curved manner to enable focusing
of acoustic energy 620 to region of interest 630. The curvature can
be substantially spherical and/or symmetric manner, or curved in an
aspherical and/or asymmetric manner. Furthermore, variable depth
transducer 602 can comprise any other configuration to enable
focusing of acoustic energy 620 to region of interest 630, such as
to a deep treatment region of interest, a superficial region of
interest, and/or a subcutaneous region of interest. For example,
variable depth transducer 602 can be configured in any planar or
non-planar arrangement.
[0050] For temporal control, the thickness of the transduction
element of variable depth transducer 602 may be selected to provide
a center operating frequency of moderate range, for example from
approximately 750 kHz to 20 MHz. Lower frequencies, e.g., between
approximately 750 kHz and 8 MHz, can facilitate deeper penetration
and higher frequencies, e.g., between approximately 8 to 30 MHz or
more, facilitate greater resolution. As a result, an exemplary
transducer system 600 can be configured for providing treatment to
a superficial region of interest and/or to a subcutaneous region of
interest utilizing moderate frequencies below 20 MHz. For example,
an exemplary transducer system 600 can provide treatment to
superficial regions and/or to subcutaneous regions that are more
commonly addressed in cosmetic applications with an operating
frequency range from approximately 750 kHz to 1.5 MHz or more.
[0051] Electrical leads 610 are configured to enable power to be
transmitted to and signals received from variable depth transducer
602, and can comprise any wiring type, configuration and
arrangement for use with ultrasound transducers. Variable depth
transducer 602 may also be coupled to electrical leads 610 in
various manners. For example, while FIG. 6 depicts electrical leads
610 coupled to only one side of variable depth transducer 602,
electrical leads 610 may also be coupled together on an opposite
end, or any other location along variable depth transducer 602.
[0052] In addition to haying a variable depth transducer 602
configured as a variable depth device to provide for control and
focusing of acoustic energy 620 towards a region of interest 630,
in accordance with an exemplary embodiment, a variable depth
transducer may also be configured electronically to provide for
control and focusing of acoustic energy. For example, with
reference to an exemplary embodiment depicted in FIG. 7, an
exemplary electronic focusing transducer system 700 is illustrated.
Electronic focusing transducer system 700 is configured with a
variable depth transducer 702. Like transducers 502 and 602,
variable depth transducer 702 may comprise a piezoelectrically
active material, composite materials, one or more matching layers,
and/or any other materials configured for generating radiation
and/or acoustical energy. Variable depth transducer 702 may also
comprise a one-dimensional or two-dimensional array of
transducers.
[0053] In accordance with an exemplary embodiment, variable depth
transducer 702 comprises one or more transducers and/or
transduction elements that can be activated by various drive
frequencies with suitable phase delay. For example, variable depth
transducer 702 can be activated by a first drive frequency 704, and
then subsequently activated by at least one or more delayed drive
frequencies 706 or 708. The phase delay in drive frequencies allows
for focusing of acoustical energy to occur both tangentially 720
and axially 730.
[0054] The drive frequencies 704, 706, 708 transmitted to variable
depth transducer 702 may comprise substantially similar frequencies
and/or different frequencies, wherein all frequencies are in the
moderate range, i.e., between approximately 750 kHz to 20 MHz. The
delay between drive frequencies 704, 706, 708 may range from 0 ms
to approximately a full period of the drive frequency. For example,
the delay may comprise zero or approximately 1/1000th of a drive
frequency period up to 15/16.sup.th, 31/32.sup.nd or more of a
drive frequency period, with variations comprising any fraction of
a full wavelength in time delay.
[0055] Electronic phase delay focusing of variable depth transducer
702 may be done tangentially and/or axially. For example, drive
frequencies 704, 706, 708 and/or the phase associated with drive
frequencies 704, 706, 708 may be varied to provide focusing
tangentially and/or axially. In accordance with an exemplary
embodiment, variable depth transducer 702 may comprise
subaperatures that may be turned on and off to also provide
focusing tangentially and/or axially. Phased focusing may prevent
over-treatment of a region of interest by automating the focus and
treatment times for a treatment region. Thus, for example,
electronic control of variable depth transducer 702 may be
facilitated by shunting various subapertures together to control
the effective acoustic size of the source/receiver.
[0056] Thus, an exemplary transducer system can comprise a variable
depth transducer 502, 602, 702 or any other transducer
configuration for providing control and focus of acoustical and
radiation energy to more than one region of interest within a
patient. Such an exemplary transducer system can comprise a
transducer configured with or coupled to a variable depth device or
feature to provide energy to more than one region of interest.
Moreover, an exemplary transducer system can provide treatment to
superficial regions and/or to subcutaneous regions that are more
commonly addressed in cosmetic applications with an operating
frequency range below 30 MHz, or more, oven from approximately 750
kHz to 8 MHz that is not attainable by prior art low-frequency
transducers.
[0057] In accordance with another aspect of the present invention,
a variable depth acoustic transducer can also be configured for
generating high acoustic power for treatment purposes, while also
providing for good imaging capabilities. To allow for the treatment
spot size to be optimally controlled at various treatment depths,
an exemplary embodiment of the present invention may comprise a
transducer configured into an array of sub-elements.
[0058] For example, in accordance with an exemplary embodiment with
reference again to FIG. 6, variable depth transducer 602 can
comprise a plurality of sub-transduction elements, wherein any of
the plurality of sub-transduction elements may be configured to
provide for focusing energy 620, e.g., any of the plurality of
sub-transduction elements can be configured for processing acoustic
waves with a sufficient bandwidth for good axial resolution. The
sub-transduction elements may be configured such that all are
curved, e.g., with the same or varying curvatures, or with one or
more sub-transduction elements being substantially flat, with the
remaining sub-transduction elements being curved. Further, the
sub-transduction elements can be configured in any other shapes
configured to provide for control and focusing of acoustic energy
620 towards a region of interest 630.
[0059] In accordance with another exemplary embodiment of the
present invention, an exemplary variable depth transducer system
300 may be configured to enable energy deposition not only
proximate a fundamental frequency of a piezoelectric material
within the transduction element, but also at other frequencies,
such as harmonic frequencies of the material, above a fundamental
frequency, as well as resonances below a fundamental frequency.
These harmonic and below fundamental resonances may be controlled
and enabled through various focusing techniques and transducer
structures, including the adding of matching layers and/or backing
layers to shape the resonant characteristics of the transducer.
[0060] For example, energy can be suitably provided to a treatment
region at a frequency near the peak acoustic output or peak
acoustic transmit efficiency of transducer 302 when a
piezoelectrically active material is driven near its fundamental
frequency. Different sized and shaped piezoelectric materials have
different fundamental frequencies for various electrode
configurations. In accordance with an exemplary embodiment, energy
can also be deposited when the piezoelectric material is driven
above its fundamental frequency, e.g., at harmonics, or when driven
below the fundamental frequency. The use of the multiple frequency
characteristics of transducer 302 may be controlled and enabled
through various transducer configurations, acoustic control and/or
focusing techniques.
[0061] In accordance with an exemplary embodiment, the multiple
frequencies may be enabled through the concentration of acoustic
energy through the variable depth device 306. Enablement of the
multiple frequencies allows for treatment at various depths
corresponding to the different frequencies. For example, with
additional reference to the acoustic output versus frequency curve
illustrated in FIG. 8, variable depth transducer system 300 may
treat multiple regions, represented by curve 800. Driving moderate
frequencies through transducer 302 and variable depth device 306
may enable treatment of a first deep region 804, treatment of a
second shallower region 808, and treatment of a third inner region
812. With respect to treatment techniques, various therapy, imaging
and for temperature monitoring applications may be provided to
regions 804, 808, and/or 812. While three treatment regions are
depicted in FIG. 8, variable depth transducer system 300 may be
configured to enable multiple frequencies for treatment of two,
four, or more regions.
[0062] In accordance with another aspect of the invention, the
variable depth transducer 302 may be configured to provide one, two
or three-dimensional treatment applications for focusing acoustic
energy to one or more regions of interest. For example, as
discussed above, variable depth transducer 302 can be suitably
diced to form a one-dimensional array, e.g., transducer 602
comprising a single array of sub-transduction elements.
[0063] In accordance with another exemplary embodiment, variable
depth transducer 302 may be suitably diced in two-dimensions to
form a two-dimensional array. For example, with reference to FIG.
9, an exemplary two-dimensional array 900 can be suitably diced
into a plurality of two-dimensional portions 902. Two-dimensional
portions 902 can be suitably configured to focus on the treatment
region at a certain depth, and thus provide respective slices 904
of the treatment region. As a result, the two-dimensional array 900
can provide a two-dimensional slicing of the image place of a
treatment region, thus providing two-dimensional treatment.
[0064] In accordance with another exemplary embodiment, variable
depth transducer 302 may be suitably configured to provide
three-dimensional treatment. For example, to provide-three
dimensional treatment of a region of interest, with reference again
to FIG. 3, a three-dimensional system can comprise variable depth
transducer 302 configured with an adaptive algorithm, such as, for
example, one utilizing three-dimensional graphic software,
contained in a control system, such as control system 304. The
adaptive algorithm is suitably configured to receive
two-dimensional imaging, temperature and/or treatment information
relating to the region of interest, process the received
information, and then provide corresponding three-dimensional
imaging, temperature and/or treatment information.
[0065] In accordance with an exemplary embodiment, with reference
again to FIG. 9, an exemplary three-dimensional system can comprise
a two-dimensional array 900 configured with an adaptive algorithm
to suitably receive 904 slices from different image planes of the
treatment region, process the received information, and then
provide volumetric information 906, e.g., three-dimensional
imaging, temperature and/or treatment information. Moreover, after
processing the received information with the adaptive algorithm,
the two-dimensional array 900 may suitably provide therapeutic
heating to the volumetric region 906 is desired.
[0066] Alternatively rather than utilizing an adaptive algorithm,
such as three-dimensional software, to provide three-dimensional
imaging and/or temperature information, an exemplary
three-dimensional system can comprise a single variable depth
transducer 302 configured within a probe arrangement to operate
from various rotational and/or translational positions relative to
a target region.
[0067] For example, with reference to FIG. 10, a probe 1010 can be
configured to rotate around a perimeter of a treatment region 1014
to provide three-dimensional imaging and temperature information.
Probe 1010 may comprise a variable depth transducer system, such
as, for example with reference to FIG. 3, variable depth transducer
302 configured with variable depth device 306. In the exemplary
embodiment, probe 1010 may be coupled to control system 304 through
a connector 1012. Connector 1012 may comprise a wire, optical
cable, wireless connection, or any other device capable of sending
and/or receiving information from control system 304 to variable
depth transducer 302 and variable depth device 306 housed within
probe 1010.
[0068] Probe 1010 may be configured to rotate around an axis 1016
to provide three-dimensional information. The rotational movement
can comprise movement in either a clockwise or counterclockwise
direction, or both. Further, the rotational movement could include
complete or partial rotations. Thus, the rotational movement could
include movement between only two positions, or between any other
number of rotational positions. Still further, probe 1010 can be
configured to translate or sweep along axis 1016 to provide a
larger field-of-view and thus facilitate additional
three-dimensional information. Accordingly, the probe system 1000
may comprise rotational and/or translational movement suitably
configured to provide three-dimensional information.
[0069] Rotational and/or translational movement of probe 1010 may
be controlled by manually placing probe 1010 in various desired
rotational positions around the treatment region 1014. The movement
of variable depth transducer 302 within probe 1010 in various
rotational and/or translational positions can also be controlled by
any mechanical scanning device now known or hereinafter devised for
automated movement. For example, with reference to an exemplary
embodiment illustrated in FIG. 11, automated rotational and/or
translational movement may be achieved through use of a robotic arm
mechanism 1100. Robotic arm mechanism 1100 comprises a manually
and/or electromechanically actuated robotic arm 1112 coupled with a
probe 1110 and a control 1114.
[0070] Probe 1110 may comprise a variable depth transducer system,
such as variable depth transducer 302 configured with variable
depth device 306. Movement of probe 1110 is mechanically provided
though the operation of robotic arm 1112. Robotic arm 1112 may
comprise one or more sub-segments that allow precise movement and
precise measurement of position in one or more up to any direction.
Robotic arm 1112 may be driven by control system 1114. Control
system 1114 may comprise a drive box, gears or any other device for
providing mechanical movement of robotic arm 1112. Control system
1114 may also comprise a processor, a display, and/or an
input/output device. Probe 1110 may be further coupled to control
system 1114 through a wire or optical cable configured alongside or
within robotic arm 1112, a wireless connection, or any other device
capable of sending and/or receiving information from control system
1114 to variable depth transducer 302 and variable depth device 306
housed within probe 1110.
[0071] Control system 1114 may provide movement and control of
robotic arm 1112 with up to six degrees of freedom. Control system
1114 may allow for movement of robotic arm 1112 to be referenced
with one or more fixed positions in space. Control system 1114 may
also allow for movement of robotic arm 1112 to be referenced with
on or more fixed positions on a patient.
[0072] While the three-dimensional systems may include a single
acoustic transducer configured with a two-dimensional array 900 and
an adaptive algorithm to provide three-dimensional imaging,
temperature monitoring and therapeutic heating to a treatment
region; the three-dimensional system may also be configured to
include both an adaptive algorithm and rotational and/or
translational movement to provide additional information. As such,
an even larger area of treatment may be obtained through the use of
both the adaptive algorithm and the rotational and/or translational
movement.
[0073] Continuing with this example, the three-dimensional system
can be suitably configured to capture imaging and temperature
information and provide therapeutic heating from variable depth
transducer 302 once variable depth transducer 302 becomes fixedly
maintained at various rotational positions. The three-dimensional
system can also be suitably configured to capture imaging and
temperature information and provide therapeutic heating just prior
to, or just after, becoming fixedly positioned. The
three-dimensional system can also be configured to capture imaging
and temperature information and provide therapy during movement
around the various rotational positions.
[0074] In addition to one, two or three-dimensional arrays, an
exemplary variable depth transducer can also be configured within
an annular array to provide planar, focused and/or defocused
acoustical energy to more than one region of interest. For example,
in accordance with an exemplary embodiment, with reference to FIGS.
12A and 12B, an annular array 1200 comprising a plurality of rings
1202, 1204, 1206 to N. Rings 1202, 1204, 1206 to N can be
mechanically and electrically isolated into a set of individual
elements, and can create planar, focused, or defocused waves. For
example, such waves can be centered on-axis, such as by methods of
adjusting corresponding transmit and/or receive delays .tau..sub.1,
.tau..sub.2, .tau..sub.3. . . .tau..sub.n. An electronic focus can
be suitably moved along various depth positions, and can enable
variable strength or beam tightness, while an electronic defocus
can have varying amounts of defocusing. In accordance with an
exemplary embodiment, a lens can also be provided to aid focusing
or defocusing such that any time differential delays can be
reduced. Movement of annular array 1200 in one, two or
three-dimensions, or along any path, such as through use of probe
1000 and/or robotic arm mechanism 1100, may be implemented to scan
and/or treat a volume or any corresponding space within a region of
interest.
[0075] In accordance with another exemplary embodiment of the
present invention, an exemplary variable depth treatment system and
method may also be configured to provide therapeutic heating,
cooling and/or imaging of a treatment region as well as
acoustically monitoring the temperature profile or other tissue
parameter monitoring of the treatment region and the general
vicinity thereof. In accordance with an exemplary embodiment, an
exemplary variable depth system may be configured with a dynamic
feedback arrangement based on monitoring of temperature or other
tissue parameters, and/or based on imaging information to suitably
adjust the spatial anchor temporal characteristics of the variable
depth transducer. Such imaging and other temperature or tissue
parameter information can be suitably collected from ultrasound
signals transmitted from an exemplary variable depth transducer, or
from separate devices configured for collecting such information,
e.g., a laser device configured with a receiver for profiling
temperature, imaging or other such information.
[0076] For example, with reference again to FIG. 4, such feedback
information can be utilized to dynamically adjust the height, e.g.,
with a standoff, or distance of a transduction element within
variable depth transducer system 402 from superficial layer 412.
Such adjustment of the distance and/or location of variable depth
transducer system 402 can be controlled either manually or
mechanically. Changing the distance of variable depth transducer
system 402 can result in a change in the depth of penetration of
the acoustical energy within a region of interest, for example,
from an inner region 422 to a deep region 410. The depth of
penetration of the acoustical energy also be suitably changed by
changing the temperature or any couplant configured between
variable depth transducer system 402 from superficial layer 412,
and/or the temperature of any coolant.
[0077] Feedback information may be suitably generated or provided
by any one or more acoustical sources, such as B-scan images,
A-lines, Doppler or color flow images, surface acoustic wave
devices, hydrophones, elasticity measurement, or shear wave based
devices. In addition, optical sources can also be utilized, such as
video and/or infrared cameras, laser Doppler imagers, optical
coherence tomography imagers and temperature sensors. Further,
feedback information can also be suitably provided by
semiconductors, such as thermistors or solid state temperature
sensors, by electronic and electromagnetic sensors, such as
impedance and capacitance measurement devices and/or thermocouples,
and by mechanical sensors, such as stiffness gages, strain gapes or
stress measurement sensors, or any suitably combination thereof.
Moreover, various other switches, acoustic or other sensing
mechanisms and methods may be suitably employed to enable
transducer 402 to be acoustically coupled to one or more regions of
interest.
[0078] The present invention has been described above with
reference to various exemplary embodiments. However those skilled
in the art will recognize that changes and modifications may be
made to the exemplary embodiments without departing from the scope
of the present invention. For example, the various operational
steps, as well as the components for carrying out the operational
steps, may be implemented in alternate ways depending upon the
particular application or in consideration of any number of cost
functions associated with the operation of the system, e.g.,
various of the steps may be deleted, modified, or combined with
other steps. Further, it should be noted that while the method and
system for ultrasound treatment with a variable depth transducer as
described above is suitable for use by a medical practitioner
proximate the patient, the system can also be accessed remotely,
the medical practitioner can view through a remote display having
imaging information transmitted in various manners of
communication, such as by satellite/wireless or by wired
connections such as IP or digital cable networks and the like, and
can direct a local practitioner as to the suitable placement for
the transducer. Moreover, while the various exemplary embodiments
may comprise non-invasive configurations, an exemplary variable
depth transducer system can also be configured for at least some
level of invasive treatment application. These and other changes or
modifications are intended to be included within the scope of the
present invention, as set forth in the following claims.
* * * * *