U.S. patent application number 14/200852 was filed with the patent office on 2014-07-03 for noninvasive tissue tightening system.
This patent application is currently assigned to Guided Therapy Systems, LLC. The applicant listed for this patent is Guided Therapy Systems, LLC. Invention is credited to Peter G. Barthe, Inder Raj S. Makin, Brian D. O'Connor, Michael H. Slayton.
Application Number | 20140187944 14/200852 |
Document ID | / |
Family ID | 49380764 |
Filed Date | 2014-07-03 |
United States Patent
Application |
20140187944 |
Kind Code |
A1 |
Slayton; Michael H. ; et
al. |
July 3, 2014 |
NONINVASIVE TISSUE TIGHTENING SYSTEM
Abstract
Systems and methods for noninvasive tissue tightening are
disclosed. Thermal treatment of tissues such as superficial
muscular aponeurosis system (SMAS) tissue, muscle, adipose tissue,
dermal tissue, and combinations thereof are described. In one
aspect, a system is configured for treating tissue through delivery
of ultrasound energy at a depth, distribution, temperature, and
energy level to achieve a desired cosmetic effect.
Inventors: |
Slayton; Michael H.; (Tempe,
AZ) ; Barthe; Peter G.; (Phoenix, AZ) ; Makin;
Inder Raj S.; (Mesa, AZ) ; O'Connor; Brian D.;
(Phoenix, AZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Guided Therapy Systems, LLC |
Mesa |
AZ |
US |
|
|
Assignee: |
Guided Therapy Systems, LLC
Mesa
AZ
|
Family ID: |
49380764 |
Appl. No.: |
14/200852 |
Filed: |
March 7, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13924376 |
Jun 21, 2013 |
8690780 |
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14200852 |
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13679430 |
Nov 16, 2012 |
8506486 |
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13924376 |
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|
13444336 |
Apr 11, 2012 |
8366622 |
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13679430 |
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11163151 |
Oct 6, 2005 |
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13444336 |
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60616755 |
Oct 6, 2004 |
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Current U.S.
Class: |
600/439 |
Current CPC
Class: |
A61B 8/13 20130101; A61B
8/085 20130101; A61B 8/4209 20130101; A61B 8/4444 20130101; A61N
7/00 20130101; A61B 8/4494 20130101; A61N 7/02 20130101; A61B
8/4281 20130101; A61B 8/546 20130101 |
Class at
Publication: |
600/439 |
International
Class: |
A61N 7/02 20060101
A61N007/02 |
Claims
1. (canceled)
2. An ultrasound treatment system for noninvasive tissue
tightening, the system comprising: a control system; a display; and
an ultrasound probe, wherein the ultrasound probe comprises a
housing, wherein the housing contains an ultrasound imaging
element, an ultrasound therapy element, and a motion mechanism,
wherein a portion of the housing is configured for acoustic
coupling to a skin surface, wherein the ultrasound imaging element
is connected to the display and the control system, wherein the
motion mechanism is connected to the control system, wherein the
ultrasound imaging element is configured for imaging a region of
interest under the skin surface, wherein the region of interest
comprises a tissue, wherein the tissue comprises a superficial
muscular aponeurosis system (SMAS) tissue, wherein the display is
configured to display an image of the region of interest, wherein
the ultrasound therapy element is configured for delivery of energy
at a temperature sufficient to cause shrinkage of a plurality of
collagen fibers in the SMAS tissue at a depth under the skin
surface, wherein the ultrasound therapy element is connected to the
motion mechanism, wherein the motion mechanism moves the ultrasound
therapy element to form a plurality of thermal foci at the depth
for tightening the tissue.
3. The system of claim 2, wherein the control system comprises: a
microprocessor; software; an input device; a power supply; a
communication device; a motion mechanism control; and an image
processor, wherein the ultrasound probe is connected to the control
system via a cable.
4. The system of claim 3, further comprising a multiplexer to
control a plurality of transduction elements.
5. The system of claim 2, wherein the control system comprises a
spatial control and a temporal control, the spatial control and the
temporal control controlling the delivery of energy at a
temperature sufficient to cause shrinkage of a plurality of
collagen fibers in the SMAS tissue at a depth under the skin
surface.
6. The system of claim 2, further comprising a user control switch
to activate the ultrasound therapy element.
7. The system of claim 2, wherein the therapy element is a single
element that delivers ultrasound energy at a frequency of between 4
MHz to 15 MHz, wherein the temperature sufficient to cause
tightening of the tissue is 60.degree. C. to 90.degree. C., wherein
the ultrasound therapy element is configured to deliver the energy
within a range of 3 mm to 9 mm below the skin surface, wherein the
tightening of tissue leads to any one of a face lift, a treatment
of laxity, and a treatment of sagging in the skin surface.
8. An ultrasound treatment system for noninvasive tissue
tightening, the system comprising: an ultrasound probe comprising a
housing, wherein the housing contains an ultrasound imaging
element, an ultrasound therapy element, and a motion mechanism,
wherein a portion of the housing is configured for acoustic
coupling to a skin surface, a control system; and a display,
wherein the ultrasound imaging element is in communication with the
display, wherein the ultrasound imaging element is configured for
imaging a region of interest under the skin surface, wherein the
region of interest comprises a tissue, wherein the tissue comprises
a superficial muscular aponeurosis system (SMAS) tissue, wherein
the display is configured to display an image of the region of
interest, wherein the ultrasound therapy element is in
communication with the control system, wherein the ultrasound
therapy element is configured for delivery of energy at a
temperature sufficient to cause shrinkage of a plurality of
collagen fibers in the SMAS tissue at a depth under the skin
surface, wherein the ultrasound therapy element is connected to a
portion of the motion mechanism, wherein the motion mechanism is in
communication with the control system, wherein the motion mechanism
moves the ultrasound therapy element to form a plurality of thermal
foci at the depth for tightening the tissue.
9. The system of claim 8, further comprising a user control switch
to activate the ultrasound imaging element.
10. The system of claim 8, further comprising an acoustic coupler
between the ultrasound probe and the skin surface.
11. The system of claim 8, wherein the ultrasound imaging element
and the ultrasound therapy element are in a combined
transducer.
12. The system of claim 8, wherein the ultrasound imaging element
is separate from, and co-housed with, the ultrasound therapy
element in the probe.
13. The system of claim 8, wherein the therapy element is a
spherically focused single element.
14. The system of claim 8, wherein the motion mechanism is a linear
motion mechanism for linear movement of the ultrasound therapy
element to form the plurality of thermal foci along a line at the
depth in the region of interest.
15. The system of claim 8, wherein the motion mechanism is
configured for any one of the group consisting of linear,
rotational, and variable movement of the ultrasound therapy
element.
16. The system of claim 8, wherein the motion mechanism comprises
an encoder for monitoring a position of the ultrasound therapy
element on the motion mechanism in the housing of the probe.
wherein the therapy element is a single element that delivers
ultrasound energy at a frequency of between 4 MHz to 15 MHz,
wherein the temperature sufficient to cause tightening of the
tissue is 60.degree. C. to 90.degree. C., wherein the ultrasound
therapy element is configured to deliver the energy within a range
of 3 mm to 9 mm below the skin surface, wherein the tightening of
tissue leads to any one of a face lift, a treatment of laxity, and
a treatment of sagging in the skin surface.
17. An ultrasound treatment system for noninvasive tissue
tightening, the system comprising: an ultrasound probe; and a
control system; wherein the ultrasound probe comprises a housing,
wherein the housing contains an ultrasound therapy element and a
motion mechanism, wherein a portion of the housing is configured
for acoustic coupling to a skin surface, wherein the ultrasound
therapy element is in communication with the control system,
wherein the motion mechanism is in communication with the control
system, wherein the ultrasound therapy element is configured for
delivery of energy at a temperature sufficient to cause shrinkage
of a plurality of collagen fibers in a superficial muscular
aponeurosis system (SMAS) tissue at a depth under the skin surface,
wherein the ultrasound therapy element is connected to a portion of
the motion mechanism, wherein the motion mechanism moves the
ultrasound therapy element to form a plurality of thermal foci at
the depth for tightening the tissue.
18. The system of claim 17, wherein the housing further comprises
an ultrasound imaging element, wherein the ultrasound imaging
element is configured for imaging a region of interest under the
skin surface, wherein the region of interest comprises a tissue,
wherein the tissue comprises the SMAS tissue, wherein the
ultrasound imaging element is configured to image with an imaging
frequency of between 2 MHz to 75 MHz, and wherein the tightening of
tissue leads to any one of a face lift, a treatment of laxity, and
a treatment of sagging in the skin surface.
19. The system of claim 17, wherein the ultrasound therapy element
is configured to deliver the energy within a range of 3 mm to 9 mm
below the skin surface, wherein the tightening of tissue leads to
any one of a face lift, a treatment of laxity, and a treatment of
sagging in the skin surface.
20. The system of claim 17, wherein the tightening of tissue leads
to any one of a face lift, a treatment of laxity, and a treatment
of sagging in the skin surface, wherein the control system
comprises: a microprocessor; software; an input device; a power
supply; a communication device; a motion mechanism control; and
wherein the ultrasound probe is connected to the control system via
a cable.
21. The system of claim 17, wherein the ultrasound therapy element
is configured to heat the tissue to 60.degree. C. to 90.degree. C.,
wherein the ultrasound therapy element is a single element that
delivers ultrasound energy at a frequency of between 4 MHz to 15
MHz, wherein the tightening of tissue leads to any one of a face
lift, a treatment of laxity, and a treatment of sagging in the skin
surface.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 13/924,376 titled "Noninvasive Tissue Tightening For Cosmetic
Effects" filed on Jun. 21, 2013, which is a continuation of U.S.
application Ser. No. 13/679,430 titled "Ultrasound Treatment Of
Sub-Dermal Tissue For Cosmetic Effects" filed on Nov. 16, 2012 and
issued as U.S. Pat. No. 8,506,486, which is a continuation of U.S.
application Ser. No. 13/444,336 titled "Treatment Of Sub-Dermal
Regions For Cosmetic Effects" filed on Apr. 11, 2012 and issued as
U.S. Pat. No. 8,366,622, which is a continuation of U.S.
application Ser. No. 11/163,151 titled "Method And System For
Noninvasive Face Lifts And Deep Tissue Tightening" filed on Oct. 6,
2005, now abandoned, which claims the benefit of priority to U.S.
Provisional Application No. 60/616,755, titled "Method And System
For Noninvasive Face Lifts And Deep Tissue Tightening" filed on
Oct. 6, 2004, each of which is incorporated in its entirety by
reference herein. Any and all priority claims identified in the
Application Data Sheet, or any correction thereto, are hereby
incorporated by reference under 37 CFR 1.57.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to ultrasound therapy and
imaging systems, and in particular to a method and system for
noninvasive face lifts and deep tissue tightening.
[0004] 2. Description of the Related Art
[0005] Coarse sagging of the skin and facial musculature occurs
gradually over time due to gravity and chronic changes in
connective tissue generally associated with aging. Invasive
surgical treatment to tighten such tissues is common, for example
by facelift procedures. In these treatments for connective tissue
sagging, a portion of the tissue is usually removed, and sutures or
other fasteners are used to suspend the sagging tissue structures.
On the face, the Superficial Muscular Aponeurosis System (SMAS)
forms a continuous layer superficial to the muscles of facial
expression and beneath the skin and subcutaneous fat. Conventional
face lift operations involve suspension of the SMAS through such
suture and fastener procedures.
[0006] No present procedures have been developed yet, which provide
the combination of targeted, precise, local heating to a specified
temperature region capable of inducing ablation (thermal injury) to
underlying skin and subcutaneous fat. Attempts have included the
use of radio frequency (RF) devices that have been used to produce
heating and shrinkage of skin on the face with some limited success
as a non-invasive alternative to surgical lifting procedures.
However, RF is a dispersive form of energy deposition. RF energy is
impossible to control precisely within the heated tissue volume and
depth, because resistive heating of tissues by RF energy occurs
along the entire path of electrical conduction through tissues.
Another restriction of RF energy for non-invasive tightening of the
SMAS is unwanted destruction of the overlying fat and skin layers.
The electric impedance to RF within fat, overlying the suspensory
connective structures intended for shrinking, leads to higher
temperatures in the fat than in the target suspensory structures.
Similarly, mid-infrared lasers and other light sources have been
used to non-invasively heat and shrink connective tissues of the
dermis, again with limited success. However, light is not capable
of non-invasive treatment of SMAS because light does not penetrate
deeply enough to produce local heating there. Below a depth of
approximately 1 mm, light energy is multiply scattered and cannot
be focused to achieve precise local heating.
SUMMARY OF THE INVENTION
[0007] A method and system for noninvasive face lifts and deep
tissue tightening are provided. An exemplary method and treatment
system are configured for the imaging, monitoring, and thermal
injury to treat the SMAS region. In accordance with an exemplary
embodiment, the exemplary method and system are configured for
treating the SMAS region by first, imaging of the region of
interest for localization of the treatment area and surrounding
structures, second, delivery of ultrasound energy at a depth,
distribution, timing, and energy level to achieve the desired
therapeutic effect, and third to monitor the treatment area before,
during, and after therapy to plan and assess the results and/or
provide feedback.
[0008] In accordance with an exemplary embodiment, an exemplary
treatment system comprises an imaging/therapy probe, a control
system and display system. The imaging/therapy probe can comprise
various probe and/or transducer configurations. For example, the
probe can be configured for a combined dual-mode imaging/therapy
transducer, coupled or co-housed imaging/therapy transducers, or
simply a therapy probe and an imaging probe. The control system and
display system can also comprise various configurations for
controlling probe and system functionality, including for example a
microprocessor with software and a plurality of input/output
devices, a system for controlling electronic and/or mechanical
scanning and/or multiplexing of transducers, a system for power
delivery, systems for monitoring, systems for sensing the spatial
position of the probe and/or transducers, and systems for handling
user input and recording treatment results, among others.
[0009] In accordance with an exemplary embodiment, ultrasound
imaging can be utilized for safety purposes, such as to avoid
injuring vital structures such as the facial nerve (motor nerve),
parotid gland, facial artery, and trigeminal nerve (for sensory
functions) among others. For example, ultrasound imaging can be
used to identify SMAS as the superficial layer well defined by
echoes overlying the facial muscles. Such muscles can be readily
seen and better identified by moving them, and their image may be
further enhanced via signal and image processing.
[0010] In accordance with an exemplary embodiment, ultrasound
therapy via focused ultrasound, an array of foci, a locus of foci,
a line focus, and/or diffraction patterns from single element,
multiple elements, annular array, one-, two-, or three-dimensional
arrays, broadband transducers, and/or combinations thereof, with or
without lenses, acoustic components, mechanical and/or electronic
focusing are utilized to treat the SMAS region at fixed and/or
variable depth or dynamically controllable depths and
positions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The subject matter of the invention is particularly pointed
out 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 accompanying drawing figures, in which like
parts may be referred to by like numerals:
[0012] FIG. 1 illustrates a block diagram of a treatment system in
accordance with an exemplary embodiment of the present
invention;
[0013] FIGS. 2A-2F illustrates schematic diagrams of an ultrasound
imaging/therapy and monitoring system for treating the SMAS layer
in accordance with various exemplary embodiments of the present
invention;
[0014] FIGS. 3A and 3B illustrate block diagrams of an exemplary
control system in accordance with exemplary embodiments of the
present invention;
[0015] FIGS. 4A and 4B illustrate block diagrams of an exemplary
probe system in accordance with exemplary embodiments of the
present invention;
[0016] FIG. 5 illustrates a cross-sectional diagram of an exemplary
transducer in accordance with an exemplary embodiment of the
present invention;
[0017] FIGS. 6A and 6B illustrate cross-sectional diagrams of an
exemplary transducer in accordance with exemplary embodiments of
the present invention;
[0018] FIG. 7 illustrates exemplary transducer configurations for
ultrasound treatment in accordance with various exemplary
embodiments of the present invention;
[0019] FIGS. 8A and 8B illustrate cross-sectional diagrams of an
exemplary transducer in accordance with another exemplary
embodiment of the present invention;
[0020] FIG. 9 illustrates an exemplary transducer configured as a
two-dimensional array for ultrasound treatment in accordance with
an exemplary embodiment of the present invention;
[0021] FIGS. 10A-10F illustrate cross-sectional diagrams of
exemplary transducers in accordance with other exemplary
embodiments of the present invention;
[0022] FIG. 11 illustrates a schematic diagram of an acoustic
coupling and cooling system in accordance with an exemplary
embodiment of the present invention;
[0023] FIG. 12 illustrates a block diagram of a treatment system
comprising an ultrasound treatment subsystem combined with
additional subsystems and methods of treatment monitoring and/or
treatment imaging as well as a secondary treatment subsystem in
accordance with an exemplary embodiment of the present invention;
and
[0024] FIG. 13 illustrates a schematic diagram with imaging,
therapy, or monitoring being provided with one or more active or
passive oral inserts in accordance with an exemplary embodiment of
the present invention.
DETAILED DESCRIPTION
[0025] The present invention may be described herein in terms of
various functional 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 a 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 contexts and that the exemplary
embodiments relating to a method and system for noninvasive face
lift and deep tissue tightening as described herein are merely
indicative of exemplary applications for the invention. For
example, the principles, features and methods discussed may be
applied to any SMAS-like muscular fascia, such as platysma,
temporal fascia, and/or occipital fascia, or any other medical
application. Further, various aspects of the present invention may
be suitably applied to other applications.
[0026] In accordance with various aspects of the present invention,
a method and system for noninvasive face lifts and deep tissue
tightening are provided. For example, in accordance with an
exemplary embodiment, with reference to FIG. 1, an exemplary
treatment system 100 configured to treat a region of interest 106
comprises a control system 102, an imaging/therapy probe with
acoustic coupling 104, and a display system 108. Control system 102
and display system 108 can comprise various configurations for
controlling probe 102 and overall system 100 functionality, such
as, for example, a microprocessor with software and a plurality of
input/output devices, system and devices for controlling electronic
and/or mechanical scanning and/or multiplexing of transducers, a
system for power delivery, systems for monitoring, systems for
sensing the spatial position of the probe and/or transducers,
and/or systems for handling user input and recording treatment
results, among others. Imaging/therapy probe 104 can comprise
various probe and/or transducer configurations. For example, probe
104 can be configured for a combined dual-mode imaging/therapy
transducer, coupled or co-housed imaging/therapy transducers, or
simply a separate therapy probe and an imaging probe.
[0027] In accordance with an exemplary embodiment, treatment system
100 is configured for treating the SMAS region by first, imaging of
region of interest 106 for localization of the treatment area and
surrounding structures, second, delivery of ultrasound energy at a
depth, distribution, timing, and energy level to achieve the
desired therapeutic effect, and third to monitor the treatment area
before, during, and after therapy to plan and assess the results
and/or provide feedback.
[0028] As to the treatment of the SMAS region, connective tissue
can be permanently tightened by thermal treatment to temperatures
about 60 degrees C. or higher. Upon ablating, collagen fibers
shrink immediately by approximately 30% of their length. The
shrunken fibers can produce tightening of the tissue, wherein the
shrinkage should occur along the dominant direction of the collagen
fibers. Throughout the body, collagen fibers are laid down in
connective tissues along the lines of chronic stress (tension). On
the aged face, the collagen fibers of the SMAS region are
predominantly oriented along the lines of gravitational tension.
Shrinkage of these fibers results in tightening of the SMAS in the
direction desired for correction of laxity and sagging due to
aging. The treatment comprises the ablation of specific regions of
the SMAS region and similar suspensory connective tissues.
[0029] In addition, the SMAS region varies in depth and thickness
at different locations, e.g., between 0.5 mm to 5 mm or more. On
the face, important structures such as nerves, parotid gland,
arteries and veins are present over, under or near the SMAS region.
Tightening of the SMAS in certain locations, such as the
preauricular region associated with sagging of the cheek to create
jowls, the frontal region to associated with sagging brows,
mandibular region associated with sagging neck, can be conducted.
Treating through localized heating of regions of the SMAS or other
suspensory subcutaneous connective tissue structures to
temperatures of about 60-90.degree. C., without significant damage
to overlying or distal/underlying tissue, i.e., proximal tissue, as
well as the precise delivery of therapeutic energy to SMAS regions,
and obtaining feedback from the region of interest before, during,
and after treatment can be suitably accomplished through treatment
system 100.
[0030] To further illustrate an exemplary method and system 200,
with reference to FIG. 2, imaging of a region of interest 206, such
as by imaging a region 222 and displaying images 224 of the region
of interest 206 on a display 208, to facilitate localization of the
treatment area and surrounding structures can initially be
conducted. Next, delivery of ultrasound energy 220 at a suitably
depth, distribution, timing, and energy level to achieve the
desired therapeutic effect of thermal injury or ablation to treat
SMAS region 216 can be suitably provided by probe 204 through
control by control system 202. Monitoring of the treatment area and
surrounding structures before, during, and after therapy, i.e.,
before, during, and after the delivery of ultrasound energy to SMAS
region 216, can be provided to plan and assess the results and/or
provide feedback to control system 202 and a system user.
[0031] Ultrasound imaging and providing of images 224 can
facilitate safe targeting of the SMAS layer 216. For example, with
reference to FIG. 2B, specific targeting for the delivery of energy
can be better facilitated to avoid heating vital structures such as
the facial nerve (motor nerve) 234, parotid gland (which makes
saliva) 236, facial artery 238, and trigeminal nerve (for sensory
functions) 232 among other regions. Further, use of imaging with
targeted energy delivery to provide a limited and controlled depth
of treatment can minimize the chance of damaging deep structures,
such as for example, the facial nerve that lies below the parotid,
which is typically 10 mm thick.
[0032] In accordance with an exemplary embodiment, with reference
to FIG. 2C, ultrasound imaging of region 222 of the region of
interest 206 can also be used to delineate SMAS layer 216 as the
superficial, echo-dense layer overlying facial muscles 218. Such
muscles can be seen via imaging region 222 by moving muscles 218,
for example by extensional flexing of muscle layer 218 generally
towards directions 250 and 252. Such imaging of region 222 may be
further enhanced via signal and image processing. Once SMAS layer
216 is localized and/or identified, SMAS layer 216 is ready for
treatment.
[0033] The delivery of ultrasound energy 220 at a suitably depth,
distribution, timing, and energy level is provided by probe 204
through controlled operation by control system 202 to achieve the
desired therapeutic effect of thermal injury to treat SMAS region
216. During operation, probe 204 can also be mechanically and/or
electronically scanned within tissue surface region 226 to treat an
extended area. In addition, spatial control of a treatment depth
220 can be suitably adjusted in various ranges, such as between a
wide range of approximately 0 to 15 mm, suitably fixed to a few
discrete depths, with an adjustment limited to a fine range, e.g.
approximately between 3 mm to 9 mm, and/or dynamically adjusted
during treatment, to treat SMAS layer 216 that typically lies at a
depth between approximately 5 mm to 7 mm. Before, during, and after
the delivery of ultrasound energy to SMAS region 216, monitoring of
the treatment area and surrounding structures can be provided to
plan and assess the results and/or provide feedback to control
system 202 and a system user.
[0034] For example, in accordance with an exemplary embodiment,
with additional reference to FIG. 2D, ultrasound imaging of region
222 can be used to monitor treatment by watching the amount of
shrinkage of SMAS layer 216 in direction of areas 260 and 262, such
as in real time or quasi-real time, during and after energy
delivery to region 220. The onset of substantially immediate
shrinkage of SMAS layer 216 is detectable by ultrasound imaging of
region 222 and may be further enhanced via image and signal
processing. The monitoring of such shrinkage can be ideal because
it can confirm the intended therapeutic goal of noninvasive lifting
and tissue tightening; in addition, such monitoring may be used for
system feedback. In addition to image monitoring, additional
treatment parameters that can be suitably monitored in accordance
with various other exemplary embodiments may include temperature,
video, profilometry, strain imaging and/or gauges or any other
suitable spatial, temporal and/or other tissue parameters.
[0035] For example, in accordance with an exemplary embodiment of
the present invention, with additional reference to FIG. 2E, an
exemplary monitoring method and system 200 may suitably monitor the
temperature profile or other tissue parameters of the region of
interest 206, such as attenuation or speed of sound of treatment
region 222 and suitably adjust the spatial and/or temporal
characteristics and energy levels of ultrasound therapy transducer
probe 204. The results of such monitoring techniques may be
indicated on display 208 in various manners, such as, for example,
by way of one-, two-, or three-dimensional images of monitoring
results 270, or may comprise an indicator 272, such as a success,
fail and/or completed/done type of indication, or combinations
thereof.
[0036] In accordance with another exemplary embodiment, with
reference to FIG. 2F, the targeting of particular region 220 within
SMAS layer 216 can be suitably be expanded within region of
interest 206 to include a combination of tissues, such as skin 210,
dermis 212, fat/adipose tissue 214, SMAS/muscular fascia/and/or
other suspensory tissue 216, and muscle 218. Treatment of a
combination of such tissues and/or fascia may be treated including
at least one of SMAS layer 216 or other layers of muscular fascia
in combination with at least one of muscle tissue, adipose tissue,
SMAS and/or other muscular fascia, skin, and dermis, can be
suitably achieved by treatment system 200. For example, treatment
of SMAS layer 216 may be performed in combination with treatment of
dermis 280 by suitable adjustment of the spatial and temporal
parameters of probe 204 within treatment system 200.
[0037] An exemplary control system 202 and display system 208 may
be configured in various manners for controlling probe and system
functionality. With reference to FIGS. 3A and 3B, in accordance
with exemplary embodiments, an exemplary control system 300 can be
configured for coordination and control of the entire therapeutic
treatment process for noninvasive face lifts and deep tissue
tightening. For example, control system 300 can suitably comprise
power source components 302, sensing and monitoring components 304,
cooling and coupling controls 306, and/or processing and control
logic components 308. Control system 300 can be configured and
optimized in a variety of ways with more or less subsystems and
components to implement the therapeutic system for controlled
thermal injury, and the embodiments in FIGS. 3A and 3B are merely
for illustration purposes.
[0038] For example, for power sourcing components 302, control
system 300 can comprise one or more direct current (DC) power
supplies 303 configured to provide electrical energy for entire
control system 300, including power required by a transducer
electronic amplifier/driver 312. A DC current sense device 305 can
also be provided to confirm the level of power going into
amplifiers/drivers 312 for safety and monitoring purposes.
[0039] Amplifiers/drivers 312 can comprise multi-channel or single
channel power amplifiers and/or drivers. In accordance with an
exemplary embodiment for transducer array configurations,
amplifiers/drivers 312 can also be configured with a beamformer to
facilitate array focusing. An exemplary beamformer can be
electrically excited by an oscillator/digitally controlled waveform
synthesizer 310 with related switching logic.
[0040] The power sourcing components can also include various
filtering configurations 314. For example, switchable harmonic
filters and/or matching may be used at the output of
amplifier/driver 312 to increase the drive efficiency and
effectiveness. Power detection components 316 may also be included
to confirm appropriate operation and calibration. For example,
electric power and other energy detection components 316 may be
used to monitor the amount of power going to an exemplary probe
system.
[0041] Various sensing and monitoring components 304 may also be
suitably implemented within control system 300. For example, in
accordance with an exemplary embodiment, monitoring, sensing and
interface control components 324 may be configured to operate with
various motion detection systems implemented within transducer
probe 204 to receive and process information such as acoustic or
other spatial and temporal information from a region of interest.
Sensing and monitoring components can also include various
controls, interfacing and switches 309 and/or power detectors 316.
Such sensing and monitoring components 304 can facilitate open-loop
and/or closed-loop feedback systems within treatment system
200.
[0042] Cooling/coupling control systems 306 may be provided to
remove waste heat from an exemplary probe 204, provide a controlled
temperature at the superficial tissue interface and deeper into
tissue, and/or provide acoustic coupling from transducer probe 204
to region-of-interest 206. Such cooling/coupling control systems
306 can also be configured to operate in both open-loop and/or
closed-loop feedback arrangements with various coupling and
feedback components.
[0043] Processing and control logic components 308 can comprise
various system processors and digital control logic 307, such as
one or more of microcontrollers, microprocessors,
field-programmable gate arrays (FPGAs), computer boards, and
associated components, including firmware and control software 326,
which interfaces to user controls and interfacing circuits as well
as input/output circuits and systems for communications, displays,
interfacing, storage, documentation, and other useful functions.
System software and firmware 326 controls all initialization,
timing, level setting, monitoring, safety monitoring, and all other
system functions required to accomplish user-defined treatment
objectives. Further, various control switches 308 can also be
suitably configured to control operation.
[0044] An exemplary transducer probe 204 can also be configured in
various manners and comprise a number of reusable and/or disposable
components and parts in various embodiments to facilitate its
operation. For example, transducer probe 204 can be configured
within any type of transducer probe housing or arrangement for
facilitating the coupling of transducer to a tissue interface, with
such housing comprising various shapes, contours and
configurations. Transducer probe 204 can comprise any type of
matching, such as for example, electric matching, which may be
electrically switchable; multiplexer circuits and/or
aperture/element selection circuits; and/or probe identification
devices, to certify probe handle, electric matching, transducer
usage history and calibration, such as one or more serial EEPROM
(memories). Transducer probe 204 may also comprise cables and
connectors; motion mechanisms, motion sensors and encoders; thermal
monitoring sensors; and/or user control and status related
switches, and indicators such as LEDs. For example, a motion
mechanism in probe 204 may be used to controllably create multiple
lesions, or sensing of probe motion itself may be used to
controllably create multiple lesions and/or stop creation of
lesions, e.g. for safety reasons if probe 204 is suddenly jerked or
is dropped. In addition, an external motion encoder arm may be used
to hold the probe during use, whereby the spatial position and
attitude of probe 104 is sent to the control system to help
controllably create lesions. Furthermore, other sensing
functionality such as profilometers or other imaging modalities may
be integrated into the probe in accordance with various exemplary
embodiments. Moreover, the therapy contemplated herein can also be
produced, for example, by transducers disclosed in U.S. application
Ser. No. 10/944,499, filed on Sep. 16, 2004, entitled Method And
System For Ultrasound Treatment With A Multi-Directional Transducer
and U.S. application Ser. No. 10/944,500, filed on Sep. 16, 2004,
and entitled System And Method For Variable Depth Ultrasound
Treatment, both hereby incorporated by reference.
[0045] With reference to FIGS. 4A and 4B, in accordance with an
exemplary embodiment, a transducer probe 400 can comprise a control
interface 402, a transducer 404, coupling components 406, and
monitoring/sensing components 408, and/or motion mechanism 410.
However, transducer probe 400 can be configured and optimized in a
variety of ways with more or less parts and components to provide
ultrasound energy for controlled thermal injury, and the embodiment
in FIGS. 4A and 4B are merely for illustration purposes.
[0046] Control interface 402 is configured for interfacing with
control system 300 to facilitate control of transducer probe 400.
Control interface components 402 can comprise multiplexer/aperture
select 424, switchable electric matching networks 426, serial
EEPROMs and/or other processing components and matching and probe
usage information 430, cable 428 and interface connectors 432.
[0047] Coupling components 406 can comprise various devices to
facilitate coupling of transducer probe 400 to a region of
interest. For example, coupling components 406 can comprise cooling
and acoustic coupling system 420 configured for acoustic coupling
of ultrasound energy and signals. Acoustic cooling/coupling system
420 with possible connections such as manifolds may be utilized to
couple sound into the region-of-interest, control temperature at
the interface and deeper into tissue, provide liquid-filled lens
focusing, and/or to remove transducer waste heat. Coupling system
420 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 active
elements 412 and a region of interest. In addition to providing a
coupling function, in accordance with an exemplary embodiment,
coupling system 420 can also be configured for providing
temperature control during the treatment application. For example,
coupling system 420 can be configured for controlled cooling of an
interface surface or region between transducer probe 400 and a
region of interest and beyond 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 and/or
thermal energy control of transducer probe 400.
[0048] In accordance with an exemplary embodiment, with additional
reference to FIG. 11, acoustic coupling and cooling 1140 can be
provided to acoustically couple energy and imaging signals from
transducer probe 1104 to and from the region of interest 1106, to
provide thermal control at the probe 1100 to region-of-interest
interface (skin) 1110 and deeper into tissue, and to remove
potential waste heat from the transducer probe at region 1144.
Temperature monitoring can be provided at the coupling interface
via a thermal sensor 1146 to provides a mechanism of temperature
measurement 1148 and control via control system 1102 and a thermal
control system 1142. Thermal control may consist of passive cooling
such as via heat sinks or natural conduction and convection or via
active cooling such as with peltier thermoelectric coolers,
refrigerants, or fluid-based systems comprised of pump, fluid
reservoir, bubble detection, flow sensor, flow channels/tubing 1144
and thermal control 1142.
[0049] With continued reference to FIG. 4, monitoring and sensing
components 408 can comprise various motion and/or position sensors
416, temperature monitoring sensors 418, user control and feedback
switches 414 and other like components for facilitating control by
control system 300, e.g., to facilitate spatial and/or temporal
control through open-loop and closed-loop feedback arrangements
that monitor various spatial and temporal characteristics.
[0050] Motion mechanism 410 can comprise manual operation,
mechanical arrangements, or some combination thereof. For example,
a motion mechanism driver 322 can be suitably controlled by control
system 300, such as through the use of accelerometers, encoders or
other position/orientation devices 416 to determine and enable
movement and positions of transducer probe 400. Linear, rotational
or variable movement can be facilitated, e.g., those depending on
the treatment application and tissue contour surface.
[0051] Transducer 404 can comprise one or more transducers
configured for treating of SMAS layers and targeted regions.
Transducer 404 can also comprise one or more transduction elements
and/or lenses 412. The transduction elements can comprise a
piezoelectrically active material, such as lead zirconate 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, transducer 404 can comprise any
other materials configured for generating radiation and/or
acoustical energy. Transducer 404 can also comprise one or more
matching layers configured along with the transduction element such
as coupled to the piezoelectrically active material. Acoustic
matching layers and/or damping may be employed as necessary to
achieve the desired electroacoustic response.
[0052] In accordance with an exemplary embodiment, the thickness of
the transduction element of transducer 404 can be configured to be
uniform. That is, a transduction element 412 can be configured to
have a thickness that is substantially the same throughout. In
accordance with another exemplary embodiment, the thickness of a
transduction element 412 can also be configured to be variable. For
example, transduction element(s) 412 of transducer 404 can be
configured to have a first thickness selected to provide a center
operating frequency of approximately 2 kHz to 75 MHz, such as for
imaging applications. Transduction element 412 can also be
configured with a second thickness selected to provide a center
operating frequency of approximately 2 to 400 MHz, and typically
between 4 MHz and 15 MHz for therapy application. Transducer 404
can be configured as a single broadband transducer excited with at
least two or more frequencies to provide an adequate output for
generating a desired response. Transducer 404 can also be
configured as two or more individual transducers, wherein each
transducer comprises one or more transduction element. The
thickness of the transduction elements can be configured to provide
center-operating frequencies in a desired treatment range.
[0053] Transducer 404 may be composed of one or more individual
transducers in any combination of focused, planar, or unfocused
single-element, multi-element, or array transducers, including 1-D,
2-D, and annular arrays; linear, curvilinear, sector, or spherical
arrays; spherically, cylindrically, and/or electronically focused,
defocused, and/or lensed sources. For example, with reference to an
exemplary embodiment depicted in FIG. 5, transducer 500 can be
configured as an acoustic array 502 to facilitate phase focusing.
That is, transducer 500 can be configured as an array of electronic
apertures that may be operated by a variety of phases via variable
electronic time delays. By the term "operated," the electronic
apertures of transducer 500 may be manipulated, driven, used,
and/or configured to produce and/or deliver an energy beam
corresponding to the phase variation caused by the electronic time
delay. For example, these phase variations can be used to deliver
defocused beams 508, planar beams 504, and/or focused beams 506,
each of which may be used in combination to achieve different
physiological effects in a region of interest 510. Transducer 500
may additionally comprise any software and/or other hardware for
generating, producing and/or driving a phased aperture array with
one or more electronic time delays.
[0054] Transducer 500 can also be configured to provide focused
treatment to one or more regions of interest using various
frequencies. In order to provide focused treatment, transducer 500
can be configured with one or more variable depth devices to
facilitate treatment. For example, transducer 500 may be configured
with variable depth devices disclosed in U.S. patent application
Ser. No. 10/944,500, entitled "System and Method for Variable Depth
Ultrasound", filed on Sep. 16, 2004, having at least one common
inventor and a common Assignee as the present application, and
incorporated herein by reference. In addition, transducer 500 can
also be configured to treat one or more additional ROI 510 through
the enabling of sub-harmonics or pulse-echo imaging, as disclosed
in U.S. patent application Ser. No. 10/944,499, entitled "Method
and System for Ultrasound Treatment with a Multi-directional
Transducer", filed on Sep. 16, 2004, having at least one common
inventor and a common Assignee as the present application, and also
incorporated herein by reference.
[0055] Moreover, any variety of mechanical lenses or variable focus
lenses, e.g. liquid-filled lenses, may also be used to focus and/or
defocus the sound field. For example, with reference to exemplary
embodiments depicted in FIGS. 6A and 6B, transducer 600 may also be
configured with an electronic focusing array 602 in combination
with one or more transduction elements 606 to facilitate increased
flexibility in treating ROI 610. Array 602 may be configured in a
manner similar to transducer 502. That is, array 604 can be
configured as an array of electronic apertures that may be operated
by a variety of phases via variable electronic time delays, for
example, T.sub.1, T.sub.2 . . . T.sub.j. By the term "operated,"
the electronic apertures of array 602 may be manipulated, driven,
used, and/or configured to produce and/or deliver energy in a
manner corresponding to the phase variation caused by the
electronic time delay. For example, these phase variations can be
used to deliver defocused beams, planar beams, and/or focused
beams, each of which may be used in combination to achieve
different physiological effects in ROI 610.
[0056] Transduction elements 606 may be configured to be concave,
convex, and/or planar. For example, in an exemplary embodiment
depicted in FIG. 6A, transduction elements 606 are configured to be
concave in order to provide focused energy for treatment of ROI
610. Additional embodiments are disclosed in U.S. patent
application Ser. No. 10/944,500, entitled "Variable Depth
Transducer System and Method", and again incorporated herein by
reference.
[0057] In another exemplary embodiment, depicted in FIG. 6B,
transduction elements 606 can be configured to be substantially
flat in order to provide substantially uniform energy to ROI 610.
While FIGS. 6A and 6B depict exemplary embodiments with
transduction elements 604 configured as concave and substantially
flat, respectively, transduction elements 604 can be configured to
be concave, convex, and/or substantially flat. In addition,
transduction elements 604 can be configured to be any combination
of concave, convex, and/or substantially flat structures. For
example, a first transduction element can be configured to be
concave, while a second transduction element can be configured to
be substantially flat.
[0058] With reference to FIGS. 8A and 8B, transducer 800 can be
configured as single-element arrays, wherein a single-element 802,
e.g., a transduction element of various structures and materials,
can be configured with a plurality of masks 804, such masks
comprising ceramic, metal or any other material or structure for
masking or altering energy distribution from element 802, creating
an array of energy distributions 808. Masks 804 can be coupled
directly to element 802 or separated by a standoff 806, such as any
suitably solid or liquid material.
[0059] An exemplary transducer 404 can also be configured as an
annular array to provide planar, focused and/or defocused
acoustical energy. For example, with reference to FIGS. 10A and
10B, in accordance with an exemplary embodiment, an annular array
1000 can comprise a plurality of rings 1012, 1014, 1016 to N. Rings
1012, 1014, 1016 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 1020 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
and/or convex or concave shaped annular array 1000 can also be
provided to aid focusing or defocusing such that any time
differential delays can be reduced. Movement of annular array 1000
in one, two or three-dimensions, or along any path, such as through
use of probes and/or any conventional robotic arm mechanisms, may
be implemented to scan and/or treat a volume or any corresponding
space within a region of interest.
[0060] Transducer 404 can also be configured in other annular or
non-array configurations for imaging/therapy functions. For
example, with reference to FIGS. 10C-10F, a transducer can comprise
an imaging element 1012 configured with therapy element(s) 1014.
Elements 1012 and 1014 can comprise a single-transduction element,
e.g., a combined imaging/transducer element, or separate elements,
can be electrically isolated 1022 within the same transduction
element or between separate imaging and therapy elements, and/or
can comprise standoff 1024 or other matching layers, or any
combination thereof. For example, with particular reference to FIG.
10F, a transducer can comprise an imaging element 1012 having a
surface 1028 configured for focusing, defocusing or planar energy
distribution, with therapy elements 1014 including a
stepped-configuration lens configured for focusing, defocusing, or
planar energy distribution.
[0061] In accordance with various exemplary embodiments of the
present invention, transducer 404 may be configured to provide one,
two and/or three-dimensional treatment applications for focusing
acoustic energy to one or more regions of interest. For example, as
discussed above, transducer 404 can be suitably diced to form a
one-dimensional array, e.g., transducer 602 comprising a single
array of sub-transduction elements.
[0062] In accordance with another exemplary embodiment, transducer
404 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, 907 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.
[0063] In accordance with another exemplary embodiment, transducer
404 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. 1, a
three-dimensional system can comprise a transducer within probe 104
configured with an adaptive algorithm, such as, for example, one
utilizing three-dimensional graphic software, contained in a
control system, such as control system 102. The adaptive algorithm
is suitably configured to receive two-dimensional imaging,
temperature and/or treatment or other tissue parameter information
relating to the region of interest, process the received
information, and then provide corresponding three-dimensional
imaging, temperature and/or treatment information.
[0064] 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 as desired.
[0065] In accordance with other exemplary embodiments, 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 transducer 404 configured within a probe arrangement to
operate from various rotational and/or translational positions
relative to a target region.
[0066] To further illustrate the various structures for transducer
404, with reference to FIG. 7, ultrasound therapy transducer 700
can be configured for a single focus, an array of foci, a locus of
foci, a line focus, and/or diffraction patterns. Transducer 700 can
also comprise single elements, multiple elements, annular arrays,
one-, two-, or three-dimensional arrays, broadband transducers,
and/or combinations thereof, with or without lenses, acoustic
components, and mechanical and/or electronic focusing. Transducers
configured as spherically focused single elements 702, annular
arrays 704, annular arrays with damped regions 706, line focused
single elements 708, 1-D linear arrays 710, 1-D curvilinear arrays
in concave or convex form, with or without elevation focusing 712,
2-D arrays 714, and 3-D spatial arrangements of transducers may be
used to perform therapy and/or imaging and acoustic monitoring
functions. For any transducer configuration, focusing and/or
defocusing may be in one plane or two planes via mechanical focus
720, convex lens 722, concave lens 724, compound or multiple lenses
726, planar form 728, or stepped form, such as illustrated in FIG.
10F. Any transducer or combination of transducers may be utilized
for treatment. For example, an annular transducer may be used with
an outer portion dedicated to therapy and the inner disk dedicated
to broadband imaging wherein such imaging transducer and therapy
transducer have different acoustic lenses and design, such as
illustrated in FIG. 10C-10F.
[0067] Moreover, such transduction elements 700 may comprise a
piezoelectrically active material, such as lead zirconate 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. Transduction elements 700 may
also comprise one or more matching layers configured along with the
piezoelectrically active material. In addition to or instead of
piezoelectrically active material, transduction elements 700 can
comprise any other materials configured for generating radiation
and/or acoustical energy. A means of transferring energy to and
from the transducer to the region of interest is provided.
[0068] In accordance with another exemplary embodiment, with
reference to FIG. 12, an exemplary treatment system 200 can be
configured with and/or combined with various auxiliary systems to
provide additional functions. For example, an exemplary treatment
system 1200 for treating a region of interest 1202 can comprise a
control system 1206, a probe 1204, and a display 1208. Treatment
system 1200 further comprises an auxiliary imaging subsystem 1272
and/or auxiliary monitoring modality 1274 may be based upon at
least one of photography and other visual optical methods, magnetic
resonance imaging (MRI), computed tomography (CT), optical
coherence tomography (OCT), electromagnetic, microwave, or radio
frequency (RF) methods, positron emission tomography (PET),
infrared, ultrasound, acoustic, or any other suitable method of
visualization, localization, or monitoring of SMAS layers within
region-of-interest 1202, including imaging/monitoring enhancements.
Such imaging/monitoring enhancement for ultrasound imaging via
probe 1204 and control system 1206 could comprise M-mode,
persistence, filtering, color, Doppler, and harmonic imaging among
others; furthermore an ultrasound treatment system 1270, as a
primary source of treatment, may be combined with a secondary
treatment subsystem 1276, including radio frequency (RF), intense
pulsed light (IPL), laser, infrared laser, microwave, or any other
suitable energy source.
[0069] In accordance with another exemplary embodiment, with
reference to FIG. 13, treatment composed of imaging, monitoring,
and/or therapy to a region of interest may be further aided,
augmented, and/or delivered with passive or active devices 1304
within the oral cavity. For example, if passive or active device
1304 is a second transducer or acoustic reflector acoustically
coupled to the cheek lining it is possible to obtain through
transmission, tomographic, or round-trip acoustic waves which are
useful for treatment monitoring, such as in measuring acoustic
speed of sound and attenuation, which are temperature dependent;
furthermore such a transducer could be used to treat and/or image.
In addition an active, passive, or active/passive object 1304 may
be used to flatten the skin, and/or may be used as an imaging grid,
marker, or beacon, to aid determination of position. A passive or
active device 1304 may also be used to aid cooling or temperature
control. Natural air in the oral cavity may also be used as passive
device 1304 whereby it may be utilized to as an acoustic reflector
to aid thickness measurement and monitoring function.
[0070] 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. 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.
* * * * *