U.S. patent application number 11/528189 was filed with the patent office on 2008-03-27 for cooling devices with flexible sensors.
This patent application is currently assigned to Juniper Medical, Inc.. Invention is credited to Mitchell Levinson, Jesse N. Rosen.
Application Number | 20080077201 11/528189 |
Document ID | / |
Family ID | 38222505 |
Filed Date | 2008-03-27 |
United States Patent
Application |
20080077201 |
Kind Code |
A1 |
Levinson; Mitchell ; et
al. |
March 27, 2008 |
Cooling devices with flexible sensors
Abstract
A device for exchanging heat with a subject having skin is
provided. The device includes a heat exchanging member having a
heat transfer surface configured to form a heat conducting
interface with the subject's skin. The device further includes a
substantially flexible sensing device disposed in the interface
between the heat exchanging member and the subject's skin. The
sensing device is configured to measure a parameter of the
interface without substantially impeding heat transfer between the
heat exchanging member and the subject's skin.
Inventors: |
Levinson; Mitchell;
(Pleasanton, CA) ; Rosen; Jesse N.; (Albany,
CA) |
Correspondence
Address: |
PERKINS COIE LLP;PATENT-SEA
P.O. BOX 1247
SEATTLE
WA
98111-1247
US
|
Assignee: |
Juniper Medical, Inc.
Pleasanton
CA
|
Family ID: |
38222505 |
Appl. No.: |
11/528189 |
Filed: |
September 26, 2006 |
Current U.S.
Class: |
607/96 ;
600/549 |
Current CPC
Class: |
A61B 2018/00744
20130101; A61B 5/6843 20130101; A61B 2090/064 20160201; A61F
2007/0228 20130101; G05D 23/24 20130101; G05D 23/1919 20130101;
A61F 2007/0075 20130101; A61F 2007/029 20130101; A61B 5/411
20130101; A61B 2018/00023 20130101; A61B 2018/00011 20130101; A61B
2018/00791 20130101; A61F 2007/0001 20130101; A61B 2018/00047
20130101; A61B 2017/00092 20130101; A61B 2017/00088 20130101; A61B
2017/00101 20130101; G05D 23/22 20130101; A61F 7/10 20130101; A61B
2562/164 20130101 |
Class at
Publication: |
607/96 ;
600/549 |
International
Class: |
A61F 7/00 20060101
A61F007/00; A61F 7/12 20060101 A61F007/12 |
Claims
1. A device for removing heat from subcutaneous lipid-rich cells of
a subject having skin, comprising: a heat exchanging member having
a heat transfer surface configured to form a heat conducting
interface with the subject's skin to remove heat from the
lipid-rich cells such that the lipid-rich cells are substantially
affected while non-lipid-rich cells in the epidermis are not
substantially affected; and a substantially flexible sensing device
disposed in the interface between the heat exchanging member and
the subject's skin, wherein the sensing device is configured to
sense a parameter at the interface.
2. The device of claim 1 wherein the sensing device is further
configured to sense a parameter at the interface without
substantially impeding heat transfer between the heat exchanging
member and the subject's skin.
3. The device of claim 1, further comprising a thermally conductive
sleeve configured to be releasably retained on the heat exchanging
member, wherein the sensing element is incorporated into the
sleeve.
4. The device of claim 1, wherein the sensing device is a
temperature sensor.
5. The device of claim 1, wherein the sensing device includes a
substrate and a temperature sensor disposed on the substrate.
6. The device of claim 5, wherein the temperature sensor includes
first and second metal traces deposited on the substrate, the first
and second metal traces at least partially contacting each other to
form a bi-metal junction.
7. The device of claim 1, wherein the sensing device includes a
first surface corresponding to the heat transfer surface and a
second surface opposite the first surface and corresponding to the
subject's skin, and wherein a first sensor is disposed on the first
surface and a second sensor is disposed on the second surface.
8. The device of claim 1, wherein the sensing device includes a
pressure sensor and a temperature sensor.
9. The device of claim 1, further comprising a measuring circuit in
electrical communication with the sensing device and configured to
convert electrical temperature signals from the sensing device to
temperatures in degrees Celsius or Fahrenheit.
10. The device of claim 9, further comprising a logic controller in
electrical communication with the measuring circuit and configured
to control a temperature of the subject's skin and/or the heat
exchanging member based on the interface temperature measured by
the sensing device.
11. The device of claim 1, further comprising a plurality of
sensing devices configured to provide temperature information about
the interface at regions on the heat exchanging member.
12. A sensing device for measuring parameters of a heat transfer
interface between a subject having skin and a cooling device,
comprising: a substantially flexible substrate positioned in the
heat transfer interface between the subject's skin and the cooling
device, the substrate having a surface facing the cooling device;
and a sensor disposed on the surface of the substrate, the sensor
configured to measure a temperature of the heat transfer interface
without substantially impeding heat transfer between the cooling
device and the subject's skin.
13. The sensing device of claim 12 wherein with heat transfer
interface is configured to remove heat from the lipid-rich cells of
the subject's skin such that the lipid-rich cells are substantially
affected while non-lipid-rich cells in the epidermis are not
substantially affected.
14. The sensing device of claim 12 wherein the sensor is a
temperature sensor.
15. The sensing device of claim 14, wherein the temperature sensor
includes a thermocouple type selected from the group consisting of
the types J, K, T, E, N, R, S, U, and B.
16. The sensing device of claim 15, wherein the temperature sensor
includes a first metal portion and a second metal portion spaced
apart from the first metal portion, the first and second metal
portions forming a bi-metal junction.
17. The sensing device of claim 15, wherein the temperature sensor
includes two metal films sputtered, etched, or printed onto the
substrate.
18. The sensing device of claim 14, wherein the temperature sensor
is a first temperature sensor and the surface is a first surface,
and wherein the substrate further includes a second surface
opposite the first surface, and the device further includes a
second temperature sensor disposed on the second surface.
19. The sensing device of claim 14, further comprising a pressure
sensor disposed on the surface.
20. The sensing device of claim 14, wherein the temperature sensor
includes one of a thermistor, a Resistive Temperature Detector or a
thermopile deposited onto the substrate.
21. The sensing device of claim 20, wherein the temperature sensor
is a metal foil type Resistive Temperature Detector.
22. The sensing device of claim 14, further comprising a measuring
circuit in electrical communication with the temperature sensor and
configured to convert electrical signals from the temperature
sensor to temperatures in degrees Celsius or Fahrenheit.
23. A method of applying a cooling device configured for removing
heat from a subject having skin, comprising: disposing a sensing
device proximate to the cooling device, the sensing device being
substantially flexible and at least partially conforming to the
cooling device; positioning the cooling device and the sensing
device proximate to the subject's skin, wherein the cooling device
and the subject's skin form a heat transfer interface, in which the
sensing device is positioned; measuring a parameter of the heat
transfer interface using the sensing device; and removing heat from
a region of the subject's skin under the epidermis such that
lipid-rich cells are substantially affected while non-lipid-rich
cells in the epidermis are not substantially affected.
24. The method of claim 23, wherein the lipid-rich cells are
adipocytes.
25. The method of claim 23, further comprising controlling a rate
of heat removal from the subject's skin to the cooling device based
on a measured parameter of the heat transfer interface.
26. The method of claim 23, further comprising maintaining a
temperature of the heat transfer interface based on a measured
temperature of the heat transfer interface.
27. The method of claim 23, further comprising, indicating a
temperature alarm if a measured temperature of the heat transfer
interface is outside a specified target range.
28. The method of claim 23, wherein the sensing device includes a
substrate having a first surface facing the cooling device and a
second surface opposite the first surface, and wherein the sensing
device further includes a first temperature sensor disposed on the
first surface and a second temperature sensor disposed on the
second surface, the method further comprising: measuring a
temperature of the cooling device using the first temperature
sensor; and measuring a temperature of the subject's skin using the
second temperature sensor.
29. The method of claim 23, wherein the sensing device further
includes a pressure sensor, the method further comprising: pressing
the cooling device and the sensing device against the subject's
skin; measuring a pressure between the cooling device and the
subject's skin using the pressure sensor; and if the measured
pressure is not less than a pressure threshold, indicating
sufficient contact between the cooling device and the subject's
skin; and if the measured pressure is less than the pressure
threshold, indicating insufficient contact between the cooling
device and the subject's skin.
30. The method of claim 23, wherein the sensing device is
incorporated into a sleeve, the method further comprising isolating
the cooling device from the subject's skin using the sleeve.
Description
TECHNICAL FIELD
[0001] The present application relates to cooling devices, systems,
and methods for exchanging heat with subcutaneous lipid-rich cells
of a subject.
BACKGROUND
[0002] As statistics have shown, excess body fat increases the
likelihood of developing various diseases and can detract from
personal appearance and athletic performance. One conventional
technique of controlling excess body fat is liposuction that can
selectively remove body fat to sculpt a person's body. One drawback
of liposuction is that it is a complex surgical procedure that can
have serious and occasionally even fatal complications.
[0003] Conventional non-invasive treatments for removing excess
body fat typically include topical agents, weight-loss drugs,
regular exercise, dieting, or a combination of these treatments.
One drawback of these treatments is that they may not be effective
or even possible under certain circumstances. For example, when a
person is physically injured or ill, regular exercise may not be an
option. Similarly, weight-loss drugs or topical agents are not an
option when they cause an allergic or negative reaction.
[0004] Other non-invasive treatment methods include applying heat
to a zone of subcutaneous lipid-rich cells. U.S. Pat. No. 5,948,011
discloses altering subcutaneous body fat and/or collagen by heating
the subcutaneous fat layer with radiant energy while cooling the
surface of the skin. Another promising method of reducing
subcutaneous fat cells is to cool the target cells as disclosed in
U.S. Patent Publication No. 2003/0220674, the entire disclosure of
which is incorporated herein. U.S. Patent Publication No.
2003/0220674 also discloses methods for selective removal of
lipid-rich cells, and avoidance of damage to other structures
including dermal and epidermal cells.
[0005] In any of these non-invasive treatment methods, temperatures
at heat transfer interfaces (e.g., between a treatment device and a
skin surface) are important for safety reasons. High interface
temperatures may cause scorching of the skin surface, and low
interface temperatures may cause frostbite. Therefore, effective
devices and methods for accurately measuring the interface
temperatures would be desirable.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] In the drawings, identical reference numbers identify
similar elements or acts. The sizes and relative positions of
elements in the drawings are not necessarily drawn to scale. For
example, the shapes of various elements and angles are not drawn to
scale, and some of these elements are arbitrarily enlarged and
positioned to improve drawing legibility. Further, the particular
shapes of the elements as drawn are not intended to convey any
information regarding the actual shape of the particular elements,
and have been solely selected for ease of recognition in the
drawings.
[0007] FIG. 1 is an isometric view of a system for exchanging heat
with a subject in accordance with an embodiment of the
invention.
[0008] FIG. 2 is a partially exploded isometric view of a cooling
device with flexible sensors in accordance with an embodiment of
the invention.
[0009] FIG. 3 is a partially exploded isometric view of a cooling
device with flexible sensors in accordance with another embodiment
of the invention.
[0010] FIG. 4 is a front view of a flexible sensing device in
accordance with another embodiment of the invention.
[0011] FIG. 5 is a back view of a flexible sensing device in
accordance with another embodiment of the invention.
[0012] FIG. 6 is a front view of a flexible sensing device in
accordance with a further embodiment of the invention.
[0013] FIG. 7 is a block diagram showing computing system software
modules for exchanging heat with a subject in accordance with an
embodiment of the invention.
DETAILED DESCRIPTION
A. Overview
[0014] The present disclosure describes devices, systems, and
methods for exchanging heat with subcutaneous lipid-rich cells. The
term "subcutaneous tissue" means tissue lying underneath the dermis
and includes adipocytes (fat cells) and subcutaneous fat. It will
be appreciated that several of the details set forth below are
provided to describe the following embodiments in a manner
sufficient to enable a person skilled in the relevant art to make
and use the disclosed embodiments. Several of the details and
advantages described below, however, may not be necessary to
practice certain embodiments of the invention. Additionally, the
invention can include other embodiments that are within the scope
of the claims but are not described in detail with respect to FIGS.
1-7.
[0015] Reference throughout this specification to "one embodiment"
or "an embodiment" means that a particular feature, structure, or
characteristic described in connection with the embodiment is
included in at least one embodiment of the present invention. Thus,
the occurrences of the phrases "in one embodiment" or "in an
embodiment" in various places throughout this specification are not
necessarily all referring to the same embodiment. Furthermore, the
particular features, structures, or characteristics may be combined
in any suitable manner in one or more embodiments.
[0016] The headings provided herein are for convenience only and do
not interpret the scope or meaning of the claimed invention.
[0017] One aspect is directed toward a cooling device for removing
heat from subcutaneous lipid-rich cells of a subject's skin. The
cooling device can include a heat exchanging member having a heat
transfer surface configured to form a heat conducting interface
with the subject's skin to remove heat from the lipid-rich cells
such that the lipid-rich cells are affected while non-lipid-rich
cells in the epidermis are not affected. The cooling device can
further include a substantially flexible sensing device disposed in
the interface between the heat exchanging member and the subject's
skin, wherein the sensing device is configured to sense a parameter
at the interface without substantially impeding heat transfer
between the heat exchanging member and the subject's skin.
[0018] Another aspect is directed toward a sensing device for
measuring parameters of a heat transfer interface between a subject
having skin and a cooling device having a substantially flexible
substrate positioned in the heat transfer interface between the
subject's skin and the cooling device. The substrate can include a
temperature sensor disposed on the surface of the substrate.
According to aspects, the temperature sensor is configured to
measure a temperature of the heat transfer interface without
substantially impeding heat transfer between the cooling device and
the subject's skin.
[0019] Another aspect is directed toward a method of applying a
cooling device configured for removing heat from a subject having
skin, the method including disposing a sensing device proximate to
the cooling device, the sensing device being substantially flexible
and at least partially conforming to the cooling device. The method
can further include positioning the cooling device and the sensing
device proximate to the subject's skin, wherein the cooling device
and the subject's skin form a heat transfer interface, in which the
sensing device is positioned. The method can further include
measuring a parameter of the heat transfer interface using the
sensing device and removing heat from a region of the subject's
skin under the epidermis such that lipid-rich cells are affected
while non-lipid-rich cells in the epidermis are not affected.
B. System for Selectively Reducing Lipid-Rich Cells
[0020] FIG. 1 is an isometric view of a system 100 for exchanging
heat from subcutaneous lipid-rich cells of a subject 101 in
accordance with an embodiment of the invention. The system 100 can
include a cooling device 104 placed at an abdominal area 102 of the
subject 101 or another suitable area for exchanging heat from the
subcutaneous lipid-rich cells of the subject 101. The cooling
device 104 can be fastened to the subject 101 using, for example, a
mechanical fastener (e.g., a belt 105), an adhesive (e.g., an
epoxy), suction (e.g., a vacuum or reduced pressure) or any other
mechanisms. The cooling device 104 can be configured to heat and/or
cool the subject 101. Various embodiments of the cooling device 104
are described in more detail below with reference to FIGS. 2-7.
[0021] In one embodiment, the cooling device 104 is configured to
cool subcutaneous lipid-rich cells of the subject 101. In such
cases, the system 100 can further include a cooling unit 106 and
fluid lines 108a-b connecting the cooling device 104 to the cooling
unit 106. The cooling unit 106 can remove heat from a coolant to a
heat sink and provide the chilled coolant to the cooling device 104
via the fluid lines 108a-b. Examples of the circulating coolant
include water, glycol, synthetic heat transfer fluid, oil, a
refrigerant, and any other suitable heat conducting fluids. The
fluid lines 108a-b can be hoses or other conduits constructed from
polyethylene, polyvinyl chloride, polyurethane, and other materials
that can accommodate the particular circulating coolant. The
cooling unit 106 can be a refrigeration unit, a cooling tower, a
thermoelectric chiller, or any other device capable of removing
heat from a coolant or municipal water supply.
[0022] The cooling device 104 can also include one or more
thermoelectric elements, such as Peltier-type thermoelectric
elements. In such cases, the system 100 can further include a power
supply 110 and a processing unit 114 operatively coupled to the
cooling device 104 via electrical cables 112, 116. In one
embodiment, the power supply 110 can provide a direct current
voltage to the cooling device 104 to effectuate a heat removal rate
from the subject 101. The processing unit 114 can monitor process
parameters via sensors (not shown in FIG. 1) placed proximate to
the cooling device 104 and adjust the heat removal rate based on
the process parameters. The processing unit 114 can include any
processor, Programmable Logic Controller, Distributed Control
System, and the like.
[0023] The processing unit 114 can be in electrical communication
with an input device 118, an output device 120, and/or a control
panel 122. The input device 118 can include a keyboard, a mouse, a
touch screen, a push button, a switch, a potentiometer, and any
other device suitable for accepting user input. The output device
120 can include a display screen, a printer, a medium reader, an
audio device, and any other device suitable for providing user
feedback. The control panel 122 can include indicator lights,
numerical displays, and audio devices. In the embodiment shown in
FIG. 1, the processing unit 114, power supply 110, control panel
122, cooling unit 106, input device 118, and output device 120 are
carried by a rack 124 with wheels 126 for portability. In another
embodiment, the various components can be fixedly installed at a
treatment site.
[0024] One expected advantage of the system 100 is that the cooling
device 104 can be applied to the subject 101 irrespective of the
current physical condition of the subject 101. For example, the
system 100 can be applied even when the subject 101 is not
ambulatory or is ill. Another expected advantage is that the system
100 can remove or affect fat non-invasively without piercing the
skin of the subject 101. Yet another expected advantage is that the
system 100 is compact and can be used in an outpatient facility or
a doctor's office. A further expected advantage is that the system
100 can quickly cool lipid-rich cells in a subcutaneous layer
without requiring high-voltage power supplies.
C. Cooling Devices With Flexible Sensors
[0025] FIG. 2 is a partially exploded isometric view of a cooling
device 104 in accordance with one embodiment of the invention and
suitable for use in the system 100. In this example, the cooling
device 104 includes a heat exchanging member 130 and a sensing
device 132 affixed to the heat exchanging member 130. The cooling
device 104 is generally configured for manual positioning, and/or
it can be strapped or otherwise configured to be releasably
attached to the subject 101. The sensing device 132 is configured
to measure a parameter at an interface of the cooling device 104
and the skin of the subject 101.
[0026] The heat exchanging member 130 can include a housing 134 and
fluid ports 136a-b coupled to the fluid lines 108a-b. In one
example, the housing 134 is generally rectangular, but in other
examples, the housing 134 can be cubic, spherical, semi-spherical,
or any other desired shape. The housing 134 can include features
for attaching the sensing device 132. In the illustrated example,
the housing 134 includes a plurality of indentations 142
(identified individually as 142a-d). In other examples, the housing
134 can include threaded apertures, channels, slots, pegs, or any
other suitable attachment mechanism. The housing 134 can be
constructed from polymeric materials, metals, ceramics, woods,
and/or other suitable materials.
[0027] The heat exchanging member 130 can further include an
interface member 138 at least partially in the housing 134. The
interface member 138 has a heat exchanging surface 140 for
transferring heat to/from the subject 101. In one example, the heat
exchanging surface 140 is generally planar, but in other examples,
the heat exchanging surface 140 can be non-planar (e.g., curved,
faceted, etc.) The interface member 138 can be constructed from any
suitable material with a thermal conductivity greater than 0.05
Watts/Meter Kelvin, and in many examples, the thermal conductivity
is more than 0.1 Watts/Meter Kelvin. Examples of suitable materials
include aluminum, copper, other metals, metal alloys, graphite,
ceramics, some polymeric materials, composites, or fluids contained
in a flexible membrane. In other embodiments, portions of the heat
exchanging surface 140 can be constructed from an insulating
material with a thermal conductivity less than 0.05 Watts/Meter
Kelvin.
[0028] The sensing device 132 can include a substrate 144 having a
first surface 146a and a second surface 146b. The substrate 144 can
have a profile generally corresponding to the profile of the
interface member 138. For example, in the illustrated example, the
substrate 144 is a flat and generally rectangular film that
generally matches the profile of the illustrated heat exchanging
surface 140 of the interface member 138. In other examples, the
substrate can have curved, faceted, or other desired profiles to
correspond to the interface member 138. In further examples, the
substrate 144 can have a profile that corresponds to only a portion
of the interface member 138.
[0029] The substrate 144 can be substantially flexible to conform
to the interface member 138 and have sufficient heat conductivity.
As a result, the sensing device 132 does not substantially impede
heat transfer between the cooling device 104 and the subject 101.
In one example, the substrate 144 can be a thin film constructed
from polyimide, polyamide, polycarbonate, or any other suitable
material with sufficient heat conductivity. In another example, the
substrate 144 can be a thick film attached to a backing material
(not shown, e.g., paper, plastic, etc.) with an adhesive. According
to aspects of the invention, the substrate 144 can be peeled off
the backing material and adhered to the interface member 138 during
assembly.
[0030] The substrate 144 can also include attachment features for
affixing the sensing device 132 to the housing 134. In the
illustrated example, the substrate 144 includes clips 152
(identified individually as 152a-d) that correspond to the
indentations 142 of the housing 134. Individual clips 152 include
protrusions 154 (identified individually as 154a-d) that can fit
inside the indentations 142. During assembly, the substrate 144 is
snapped onto the housing 134 with the first surface 146a facing the
interface member 138. The clips 152 fasten the substrate 144 onto
the housing 134 when the protrusions 154 of the clips 152 engage
the indentations 142. In other examples, the substrate 144 can be
attached to the housing 134 using screws, pins, hinges, or any
other suitable attachment mechanism.
[0031] The sensing device 132 can also include at least one sensor
disposed on the first and/or second surfaces 146a-b of the
substrate 144 to measure a parameter of the interface. In the
illustrated example, the sensing device 132 includes a first
temperature sensor 148 disposed on the first surface 146a and a
second temperature sensor 150 disposed on the second surface 146b.
The first temperature sensor 148 contacts the interface member 138
after assembly to directly measure temperatures of the heat
exchanging surface 140. The second temperature sensor 150 contacts
the subject's skin to directly measure skin temperatures during
use. In other examples, the sensing device 132 can include other
types of sensors or a greater or smaller number of sensors disposed
on the substrate 144. For example, the substrate 144 can include
only one temperature sensor disposed on the second surface 146b for
measuring the skin temperatures or multiple temperature sensors on
the second surface 146b for redundancy. Alternatively, or in
conjunction with multiple sensors, the substrate can include
pressure sensors, transmissivity sensors, bioresistance sensors,
ultrasound sensors, optical sensors, infrared sensors, heat flux,
any other desired sensors, or any combination thereof.
[0032] In the illustrated example, the first and second temperature
sensors 148, 150 are configured as thermocouples as described in
more detail below with reference to FIGS. 4 and 5. In other
examples, the temperature sensors 148, 150 can be configured as
Resistive Temperature Detectors (RTD), thermistors, thermopiles, or
other types of temperature sensors as described in more detail
below with reference to FIG. 6. A thermopile is essentially a
series of thermocouples and can be wired to measure temperature
difference between two surfaces. In one embodiment, the
thermocouples are laminated onto a Kapton backing and measure the
temperature across the Kapton backing very accurately, which can
then be converted to heat flux. In a further example, the sensing
device 132 can include pressure sensors, transmissivity sensors,
bioresistance sensors, ultrasound sensors, optical sensors,
infrared sensors, heat flux, or any other desired sensors.
[0033] A coupling agent may be applied to the subject's skin or to
the interface member 138 to provide improved thermal conductivity.
The coupling agent may include polypropylene glycol, polyethylene
glycol, propylene glycol, and/or glycol. Glycols, glycerols, and
other deicing chemicals are efficient freezing-point depressants
and act as a solute to lower the freezing point of the coupling
agent. Propylene glycol (CH3CHOHCH2OH) is one exemplary component
of deicer or non-freezing coupling agents. Other components include
polypropylene glycol (PPG), polyethylene glycol (PEG), polyglycols,
glycols, ethylene glycol, dimethyl sulfoxide, polyvinyl pyridine,
calcium magnesium acetate, sodium acetate, and/or sodium formate.
The coupling agent preferably has a freezing point in the range of
-40.degree. C. to 0.degree. C., more preferably below -10.degree.
C. as further described in U.S. Provisional Application 60/795,799,
entitled Coupling Agent For Use With a Cooling Device For Improved
Removal of Heat From Subcutaneous Lipid-Rich Cells, filed on Apr.
28, 2006, herein incorporated in its entirety by reference.
[0034] In operation, an operator can place the cooling device 104
proximate to the subject's skin to form a heat exchanging
interface. In one embodiment, the operator can press the cooling
device 104 against the subject's skin. In another embodiment, the
operator can clamp a portion of the subject's skin between the
cooling device 104 and another device, such as a device similar in
function and structure to the cooling device 104. The operator can
then exchange heat with the subject's skin using the cooling device
104. In one embodiment, the operator can cool the subject's
subcutaneous tissues by circulating a coolant through the heat
exchanging member 130 via the fluid lines 108a-b. Heat can then be
removed from the subject's skin, past the sensing device 132, to
the heat exchanging member 130. By cooling the subcutaneous tissues
to a temperature lower than 37.degree. C., preferably between about
-20.degree. C. to about 20.degree. C., more preferably between
about -20.degree. C. to about 10.degree. C., more preferably
between about -15.degree. C. to about 5.degree. C., more preferably
between about -10.degree. C. to about 0.degree. C., subcutaneous
lipid-rich cells can be selectively affected. The affected cells
are resorbed into the subject through natural processes. In any of
these embodiments, the operator can monitor and control the heat
exchanging process by measuring skin and interface temperatures
using the sensing device 132. In one example, the operator can
prevent excessively cooling the subject's skin by maintaining the
skin and/or interface temperatures at a safe level. In other
examples, the skin and/or the interface temperatures can be used as
process variables to automatically control the heat exchanging
process.
[0035] One expected advantage of using the cooling device 104 is
the reduced risk of overcooling the subject's skin because the heat
transfer interface temperature can be directly measured. As is
known, heat conduction through an object creates a temperature
gradient along a heat transfer path. For example, the temperature
of the subject's dermis can be higher than that of the subject's
epidermis during heat conduction. As a result, if the dermis
temperature or a temperature internal to the cooling device, is
used to control a cooling process, the epidermis temperature may be
too high or too low. Consequently, using directly measured
interface temperatures (e.g., at the epidermis) can reduce the risk
of overheating or overcooling the subject's skin.
[0036] The cooling device 104 can have many additional embodiments
with different and/or additional features without detracting from
the operation of the cooling device 104. For example, the cooling
device 104 can be configured to be a handheld device as described
in U.S. patent application Ser. No. 11/359,092 entitled Cooling
Device For Removing Heat From Subcutaneous Lipid-Rich Cells, the
entire disclosure of which is herein incorporated by reference. The
heat exchanging member 130 can include thermoelectric heat
exchanging members (e.g., Peltier-type elements), cryogenic
elements (e.g., liquid Nitrogen evaporator), or other types of
suitable heat exchanging elements. For example, the cooling device
104 can be configured as a plurality of thermoelectric heat
exchanging members contained on a hinged frame to allow rotation
about at least one axis as described in U.S. patent application
entitled Cooling Device Having a Plurality of Controllable
Thermoelectric Cooling Elements to Provide a Predetermined Cooling
Profile filed concurrently herewith, application number not yet
assigned, the entire disclosure of which is herein incorporated by
reference. The sensing device 132 can also be incorporated into a
sleeve that can isolate the subject 101 from the heat exchanging
member 130 as described below in more detail with reference to FIG.
3.
D. Cooling Devices With Sleeve Sensors
[0037] FIG. 3 is an alternative example of the cooling device 104
in accordance with one example of the invention for use in the
system 100. This alternative example, and those alternative
examples and other alternatives described herein, is substantially
similar to previously described examples, and common acts and
structures are identified by the same reference numbers. Only
significant differences in operation and structure are described
below. In this example, the cooling device 104 includes a sleeve
162 having a first sleeve portion 164 and a second sleeve portion
166. The first sleeve portion 164 can be generally similar in
structure and function to the sensing device 132 of FIG. 2. The
second sleeve portion 166 can be an isolation layer extending from
the first sleeve portion 164. For example, the second sleeve
portion 166 can be constructed from latex, rubber, nylon,
Kevlar.RTM., or other substantially impermeable or semipermeable
material. The second sleeve portion 166 can prevent any contact
between the subject's skin and the heat exchanging member 130. In
one example, the sleeve 162 can be reusable. In other examples, the
sleeve 162 can be disposable. The sleeve 162 may be provided
sterile or non-sterile.
[0038] The second sleeve portion 166 can also include attachment
features to affix the sleeve 162 to the housing 134. In the
illustrated example, the second sleeve portion 166 includes four
brackets 172 (identified individually as 172a-d), each located at a
corner of the second sleeve portion 166. Individual brackets 172
include an aperture 174 (identified individually as 174a-d) that
corresponds to an attachment point 170 of the housing 134. During
assembly, the apertures 174 of the brackets 172 can fit over the
attachment point 170 such that the second sleeve portion 166 at
least partially encloses the heat exchanging member 130. In another
example, the second sleeve portion 166 can include brackets that
can engage each other. For example, the bracket 172a can include a
pin that can engage the aperture 174d of the bracket 172d. During
assembly, the second sleeve portion 166 can wrap around the housing
134 and be held in place by engaging the brackets 172 with each
other. In a further example, the second sleeve portion 166 can
include a flexible member (not shown, e.g., an elastic band) at an
outer edge 176 of the second sleeve portion 166 that can hold the
sleeve 162 over the housing 134 during assembly. In a further
example, the second sleeve portion 166 can include a releasable
attachment member (not shown, e.g., Velcro.RTM. or snaps) at the
outer edge 176 of the second sleeve portion 166 that can hold the
sleeve 162 over the housing 134 during assembly. In yet another
example, adhesive can hold the second sleeve portion 166 to the
housing 134.
[0039] In addition to the expected advantages described above, one
expected advantage of using the sleeve 162 is the improved
sanitation of using the cooling device 104. The sleeve 162 can
prevent cross-contamination between the subject's skin and the heat
exchanging member 130 because the sleeve 162 is substantially
impermeable. Also, operating expense of the cooling device 104 can
be reduced because the heat exchanging member 130 does not need to
be sanitized after each use.
[0040] The sleeve 162 can have many additional embodiments with
different and/or additional features without detracting from its
operation. For example, the first and second sleeve portions 164,
166 can be constructed from the same material (e.g., polyimide) or
different materials. The sleeve 162 can include an adhesive layer
(not shown) that binds the sleeve 162 to the housing 134.
Alternatively, a coupling gel (not shown) can be applied between
the sleeve 162 and the interface member 138.
E. Sensing Devices
[0041] FIG. 4 is a front view and FIG. 5 is a back view of the
sensing device 132 illustrating several features in more detail.
The first temperature sensor 148 can include a first metal trace
180 and a second metal trace 182 spaced apart from the first metal
trace 180. The first metal trace 180 includes a first terminal
portion 186a, and the second metal trace 182 includes a second
terminal portion 186b. The first and second metal traces 180, 182
join at one end to form a bi-metal junction 184. In the illustrated
embodiment, the first and second metal traces 180, 182 are
generally parallel to each other. In other examples, the first and
second metal traces 180, 182 can be at an angle.
[0042] The first and second metal traces 180, 182 can be disposed
onto the substrate 144 using techniques including, for example,
bonding, laminating, sputtering, etching, printing, or other
suitable methods. The first and second metal traces 180, 182 can
include iron, constantan, copper, nicrosil, platinum, rhodium,
tungsten, or other suitable metals or metal alloys. The first and
second metal traces 180, 182 can form thermocouples of the types J,
K, T, E, N, R, S, U, B, and other desired types.
[0043] In the illustrated example, the second temperature sensor
150 is generally similar in structure and function to the first
temperature sensor 148. For example, the second temperature sensor
150 can include metal traces 190, 192 joined at an end to form a
bi-metal junction 194 and terminal portions 196a-b. In one
embodiment, the first and second temperature sensors 148, 150 can
be the same type (e.g., type T). In another embodiment, the first
and second temperature sensors 148, 150 can be of different
types.
[0044] FIG. 6 is an alternative example of the sensing device 132
in accordance with one example of the invention for use in the
system 100. In this example, the sensing device 132 includes an RTD
202 and a pressure sensor 204 disposed on the first surface 146a of
the substrate 144. The RTD 202 includes a first RTD terminal 206a,
a second RTD terminal 206b, and a resistance portion 208 between
the two RTD terminals 206a-b. The resistance portion 208 can be
constructed from platinum, gold, silver, copper, nickel or a
combination of metals, such as nickel-iron, or any other materials
or combinations of materials with sufficient temperature resistance
change. A preferred embodiment includes a nickel-iron metal foil.
The pressure sensor 204 includes terminals 210a-b, a pressure
sensing portion 214, and leads 212a-b connecting the terminals
210a-b to the pressure sensing portion 214. The pressure sensor 204
can be generally similar to a FlexiForcee load sensor (Model No.
A201) manufactured by Tekscan, Inc. of South Boston, Mass.
[0045] In operation, the RTD 202 senses the interface temperature
between the interface member 138 (FIG. 2) and the subject's skin,
and the pressure sensor 204 senses the pressure applied to the
subject's skin from the cooling device 104 (FIGS. 2 and 3). An
operator can then adjust the pressure applied to the subject's skin
and/or the heat exchanging rate based on these measurements.
[0046] One expected advantage of using the sensing device 132 is
the improved uniformity of heat transfer across the heat exchanging
interface. If the contact between the interface member 138 and the
subject's skin is poor, air gaps in the interface can substantially
impede the heat transfer between the cooling device 104 and the
subject's skin and cause faulty interface temperature measurements.
By using the sensing device 132, the operator can monitor and
correct the amount of pressure applied to the subject's skin to
ensure good contact at the heat exchanging interface. Consequently,
uniformity of the heat transfer across the interface can be
improved.
F. Computing System Software Modules
[0047] FIG. 7 illustrates a functional block diagram showing
exemplary software modules 440 suitable for use in the processing
unit 114 (FIG. 1). Each component can be a computer program,
procedure, or process written as source code in a conventional
programming language, such as the C++ programming language, and can
be presented for execution by the CPU of a processor 442. The
various implementations of the source code and object and byte
codes can be stored on a computer-readable storage medium or
embodied on a transmission medium in a carrier wave. The modules of
the processor 442 can include an input module 444, a database
module 446, a process module 448, an output module 450, and
optionally, a display module 451. In another embodiment, the
software modules 440 can be presented for execution by the CPU of a
network server in a distributed computing scheme.
[0048] In operation, the input module 444 accepts an operator
input, such as process setpoint and control selections, and
communicates the accepted information or selections to other
components for further processing. The database module 446
organizes records, including operating parameter 454, operator
activity 456, alarm 458, and facilitates storing and retrieving of
these records to and from a database 452. Any type of database
organization can be utilized, including a flat file system,
hierarchical database, relational database, or distributed
database, such as provided by Oracle Corporation, Redwood Shores,
Calif.
[0049] The process module 448 generates control variables based on
sensor readings 460 obtained from the sensing device 132 (FIG. 2),
and the output module 450 generates output signals 462 based on the
control variables. For example, the output module 450 can convert
the generated control variables from the process module 448 into
4-20 mA output signals 462 suitable for a direct current voltage
modulator. The processor 442 optionally can include the display
module 451 for displaying, printing, or downloading the sensor
readings 460 and output signals 462 via devices such as the output
device 120 (not shown). A suitable display module 451 can be a
video driver that enables the processor 442 to display the sensor
readings 460 on the output device 120.
[0050] Throughout the description and the claims, the words
"comprise," "comprising," and the like, unless the context clearly
requires otherwise, are to be construed in an inclusive sense as
opposed to an exclusive or exhaustive sense; that is to say, in a
sense of "including, but not limited to." Words using the singular
or plural number also include the plural or singular number,
respectively. When the claims use the word "or" in reference to a
list of two or more items, that word covers all of the following
interpretations of the word: any of the items in the list, all of
the items in the list, and any combination of the items in the
list.
[0051] The above detailed descriptions of embodiments of the
invention are not intended to be exhaustive or limit the invention
to the precise form disclosed above. While specific embodiments of,
and examples for, the invention are described above for
illustrative purposes, various equivalent modifications are
possible within the scope of the invention, as those skilled in the
relevant art will recognize. For example, while steps are presented
in a given order, alternative embodiments may perform steps in a
different order. The various embodiments described herein can be
combined to provide further embodiments.
[0052] In general, the terms used in the following claims should
not be construed to limit the invention to the specific embodiments
disclosed in the specification, unless the above detailed
description explicitly defines such terms. While certain aspects of
the invention are presented below in certain claim forms, the
inventors contemplate the various aspects of the invention in any
number of claim forms. Accordingly, the inventors reserve the right
to add additional claims after filing the application to pursue
such additional claim forms for other aspects of the invention.
* * * * *