U.S. patent application number 13/073863 was filed with the patent office on 2011-09-22 for ultrasonic method and device for wound treatment.
Invention is credited to Eilaz Babaev.
Application Number | 20110230795 13/073863 |
Document ID | / |
Family ID | 33302763 |
Filed Date | 2011-09-22 |
United States Patent
Application |
20110230795 |
Kind Code |
A1 |
Babaev; Eilaz |
September 22, 2011 |
ULTRASONIC METHOD AND DEVICE FOR WOUND TREATMENT
Abstract
An apparatus and method are provided for applying a medicament
to tissue, and delivering ultrasonic energy from a non-contact
distance from the tissue to the medicament and to the tissue,
wherein the ultrasonic energy has intensity capable of penetrating
the wound tissue to a beneficial depth to provide a therapeutic
effect to the tissue, and of sonicating the medicament for causing
the medicament to penetrate the tissue to a beneficial depth to
provide a therapeutic effect to the tissue.
Inventors: |
Babaev; Eilaz; (Minnetonka,
MN) |
Family ID: |
33302763 |
Appl. No.: |
13/073863 |
Filed: |
March 28, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10815384 |
Apr 1, 2004 |
7914470 |
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13073863 |
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10409272 |
Apr 7, 2003 |
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10815384 |
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09669312 |
Sep 25, 2000 |
6569099 |
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10409272 |
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Current U.S.
Class: |
601/2 |
Current CPC
Class: |
A61M 37/0092 20130101;
A61M 35/00 20130101; A61N 7/00 20130101; A61M 3/0275 20130101 |
Class at
Publication: |
601/2 |
International
Class: |
A61N 7/00 20060101
A61N007/00 |
Claims
1-47. (canceled)
48. An apparatus for treating a wound comprising: means for
generating ultrasonic energy; and means for delivering the
generated ultrasonic energy to the wound through a gaseous medium
from a non-contact distance from the surface of the wound in the
absence of a coupling medium and without direct contact between the
means for delivering the generated ultrasonic energy and the wound
and other patient tissue, wherein the generated ultrasonic energy
has an intensity in the range of about 0.25 watts/cm.sup.2-3
watts/cm.sup.2, and wherein the non-contact distance is at least
2.5 millimeters (mm) from the surface of the wound.
49. The apparatus according to claim 48, wherein the means for
generating includes means for generating the ultrasonic energy with
a particular amplitude indicative of an intensity capable of
achieving a therapeutic effect.
50. The apparatus according to claim 49, wherein the means for
generating further includes the means for generating the ultrasonic
energy with a frequency capable of achieving the particular
amplitude.
51. The apparatus according to claim 49, wherein the particular
amplitude is at least 10 microns.
52. The apparatus according to claim 49, wherein the frequency is
in the range of 20 kHz-5 MHz.
53. The apparatus according to claim 50, wherein the frequency is
in the range of 20-200 kHz.
54. The apparatus according to claim 50, wherein the frequency is
in the range of 20-40 kHz.
55. The apparatus according to claim 48, wherein the means for
delivering includes a radiation surface having a surface area
dimensioned for achieving delivery of the ultrasonic energy to the
wound with an intensity capable of achieving a therapeutic
effect.
56. The apparatus according to claim 48, wherein the means for
delivering includes a radiation surface having a rounded perimeter
for achieving delivery of the ultrasonic energy to the wound with
an intensity capable of achieving a therapeutic effect.
57. The apparatus according to claim 48, wherein the means for
delivering includes a radiation surface; and a selection is made of
at least one of a size of a surface area of the radiation surface,
a shape of a peripheral boundary of the radiation surface, a
frequency of the generated ultrasonic energy, and an amplitude of
the generated ultrasonic energy for achieving delivery of
ultrasonic energy to the wound with an intensity capable of
achieving a therapeutic effect.
58. The apparatus according to claim 48, wherein the means for
delivering includes a radiation surface; and a selection is made of
a combination of a size of a surface area of the radiation surface,
a shape of a peripheral boundary of the radiation surface, a shape
of the curvature of the radiation surface selected from one of
flat, concave, convex and a combination thereof, a frequency of the
generated ultrasonic energy, and an amplitude of the generated
ultrasonic energy for achieving delivery of ultrasonic energy to
the wound with an intensity capable of achieving a therapeutic
effect.
59. The apparatus according to claim 55, wherein a radiation
surface of the means for delivering is positioned from 2.5 mm to 51
cm from the surface of the wound.
60. The apparatus according to claim 48, wherein the means for
delivering is driven by a constant or modulated frequency having a
wave form selected from the group consisting of sinusoidal,
rectangular, trapezoidal and triangular wave forms.
61. The apparatus according to claim 48, wherein the method
provides a therapeutic effect selected from the group consisting of
increasing blood flow to the wound and stimulating cell growth.
62. An apparatus for treating a wound comprising: an ultrasound
generator; an ultrasound transducer including a distal tip, which
distal tip has a radiation surface from which ultrasonic energy is
emitted for delivering the generated ultrasonic energy to the wound
through a gaseous medium from a non-contact distance of at least
2.5 millimeters (mm) from the surface of the wound in the absence
of a coupling medium and without direct contact between the
ultrasound transducer and the wound and other patient tissue; and a
nozzle, wherein the ultrasound transducer is interconnected to the
ultrasound generator, and wherein the nozzle is attached to a
portion of the ultrasound transducer to shield the distal tip.
63. The apparatus of claim 62, wherein the ultrasonic energy has an
intensity in the range of about 0.25 watts/cm.sup.2-3
watts/cm.sup.2.
64. An apparatus for treating a wound comprising: means for
generating ultrasonic energy; and means for delivering the
generated ultrasonic energy to the wound through a liquid coupling
medium from a non-contact distance from the surface of the wound
without direct contact between the means for delivering the
generated ultrasonic energy and the wound and other patient tissue,
wherein the generated ultrasonic energy has an intensity in the
range of about 0.25 watts/cm.sup.2-3 watts/cm.sup.2, and wherein
the non-contact distance is at least 2.5 millimeters (mm) from the
surface of the wound.
65. The method of claim 64, wherein the liquid coupling medium does
not include a medicament.
66. The method according to claim 64, wherein the liquid coupling
medium is a medicament selected from at least one member of the
group consisting of: an antibiotic, an ointment, cream, gel,
liquid, salve, oil, powder, antibacterial agent, antiseptic agent,
insulin, analgesic agent, conditioner, surfactant, emollient, or
other active ingredients.
67. The method according to claim 66, wherein means for delivering
the generated ultrasonic energy to the wound delivers the
medicament to the wound such that the medicament penetrates the
wound to a beneficial depth to provide a therapeutic effect to the
wound.
Description
RELATED APPLICATION
[0001] This application is a continuation of application Ser. No.
10/815,384 filed Apr. 1, 2004, which in turn is a
continuation-in-part of application Ser. No. 10/409,272 filed Apr.
7, 2003, which in turn is a continuation-in-part of application
Ser. No. 09/669,312, filed Sep. 25, 2000, now U.S. Pat. No.
6,569,099, issued May 27, 2003, each of which is hereby fully
incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to methods of using ultrasonic
waves in wound treatment. More particularly, the present invention
relates to a method of applying a medicament to tissue and
delivering ultrasound energy to the medicament and the tissue.
BACKGROUND
[0003] Ultrasonic waves have been widely used in medical
applications, including for both diagnostics and therapy as well as
for many industrial applications. One diagnostic use of ultrasound
waves includes using ultrasonic waves to detect underlying
structures in an object or a human tissue. In this procedure, an
ultrasonic transducer is placed in contact with the object or
tissue via a coupling medium, and high frequency (1-10 MHz)
ultrasonic waves are directed into the tissue. Upon contact with
various underlying structures, the waves are reflected back to a
receiver adjacent the transducer. By comparison of the signals of
the ultrasonic wave as sent with the reflected ultrasonic wave as
received, an image of the underlying structure can be produced.
This technique is particularly useful for identifying boundaries
between components of tissue and can be used to detect irregular
masses, tumors, and the like.
[0004] Two therapeutic medical uses of ultrasound waves include
aerosol mist production and contact physiotherapy. Aerosol mist
production makes use of a nebulizer or inhaler to produce an
aerosol mist for creating a humid environment and delivering drugs
to the lungs. Ultrasonic nebulizers operate by the passage of
ultrasound waves of sufficient intensity through a liquid, the
waves being directed at an air-liquid interface of the liquid at a
point underneath or within the liquid. Liquid particles are ejected
from the surface of the liquid into the surrounding air following
the disintegration of capillary waves produced by the ultrasound
energy. This technique can produce a very fine dense fog or mist.
Aerosol mists produced by ultrasound are preferred over aerosol
mists produced by other methods because a smaller particle size of
aerosol can be obtained with the ultrasonic waves. One of the major
shortcoming of inhalers and nebulizers is that the aerosol mist
cannot be directed to a target area without an air stream, which
decreases the efficiency of the ultrasound energy. Ultrasonic
sprayers such as those sold by Sonic and Materials Inc., Misonix
Inc., Sono-Tek Inc. (see, for example, U.S. Pat. Nos. 4,153,201,
4,655,393, and 5,516,043) operate by passing liquid through a
central orifice of an ultrasound instrument-tip. Major
disadvantages of these sprayers include non-uniform particle size,
heating of liquid flow, and less efficiency of ultrasound waves
because of a demolished end (radiation) surface configuration of
the tip.
[0005] Contact physiotherapy applies ultrasonic waves directly to
tissue in an attempt to produce a physical change in the tissue. In
conventional ultrasound physiotherapy, an ultrasonic wave contacts
the tissue via a coupling medium. Ultrasonic waves produced by the
transducer travel through the coupling medium and into the tissue.
The coupling medium is typically a bath of liquid, a jelly applied
to the surface to be treated, or a water-filled balloon.
Conventional techniques provide ultrasonic waves having an
intensity of about 0.1 w/cm.sup.2 to 3 w/cm.sup.2 at a frequency of
about 0.8 to 3 Megahertz. The treatment is applied to a skin
surface for from about 1 to 30 minutes, two or three times a week.
The coupling medium can provide a cooling effect which dissipates
some of the energy produced by the ultrasonic transducer.
[0006] More importantly, a coupling medium or direct contact
between the tissue and ultrasonic transducer is necessary to
transmit the ultrasonic waves to the skin surface because ambient
air is a relatively poor medium for the propagation of ultrasonic
waves.
[0007] Several beneficial effects have been reported from contact
ultrasound physiotherapy, such as, for example, the following:
local improvement of the blood circulation, heating of the tissue,
accelerated enzyme activity, muscle relaxation, pain reduction, and
enhancement of natural healing processes. Despite these beneficial
effects, current techniques of medical physiotherapy using
ultrasonic waves are limited by the necessity of providing a direct
contact interface between the ultrasonic transducer and the tissue
to maintain an effective transmission of the ultrasonic waves from
the transducer to the tissue.
[0008] The necessity of direct contact with or without a coupling
medium makes current methods undesirable. Some tissue conditions
may be accessible to contact ultrasound devices but would be
impractical for contact ultrasound treatment. For example, fresh or
open wounds resulting from trauma, burns or surgical interventions
are not suitable for direct contact ultrasound treatment because of
the structural nature of the open wound and the painful condition
associated with those wounds. Moreover, conventional contact
ultrasound may have a destructive effect on these types of open
wounds due to the close proximity of an oscillating tip of an
ultrasonic transducer relative to the already damaged tissue
surface.
SUMMARY
[0009] The present invention provides an apparatus and a method for
treating tissue, the apparatus including a generator and a
transducer for generating ultrasonic energy and delivering the
ultrasonic energy to the biological tissue, from a non-contact
distance from the tissue, wherein the generated ultrasonic energy
has an intensity capable of penetrating the wound tissue to a
beneficial depth to provide a therapeutic effect to the tissue, and
of sonicating the medicament for causing the medicament to
penetrate the tissue to a beneficial depth to provide a therapeutic
effect to the tissue.
[0010] The present invention further provides an apparatus and
method for generating ultrasonic energy from a non-contact distance
from the surface of the wound; and delivering the generated
ultrasonic energy to the wound through a gaseous medium ("dry"
approach), wherein the generated ultrasonic energy has an intensity
capable of penetrating the wound tissue to a beneficial depth to
provide a therapeutic effect for decreasing the healing time for
the wound.
[0011] The present invention further relates to a method and device
for spraying ("wet" approach) a wound surface to deliver drugs,
kill bacteria, or cleanse a surface by non-contact application of
an ultrasound transducer tip. The method applies ultrasonic waves
to the wound without requiring direct or indirect (via a
traditional coupling medium) contact between the ultrasonic wave
transducer and the wound to be sprayed.
[0012] The method of the invention comprises producing a directed
spray of liquid or powder particles produced by contact of the
liquid or powder with a free end surface of an ultrasonic
transducer. The ultrasonic waves cause the spray to project
outwardly from the distal end surface of the ultrasonic transducer,
and the particle spray is directed onto the wound. The particles of
the spray provide a medium for propagation of the ultrasonic waves
emanating from the distal end surface. According to the method of
the present invention a directed particle spray created by low
frequency ultrasound waves onto a wound, delivers drug, kills
bacteria on the wound, increases blood flow, and removes dirt and
other contaminants from the wound's surface (mechanical
cleansing).
[0013] This method of drug delivery is particularly advantageous on
tissues for which local topical application of a drug is desirable
but contact with the tissue is to be avoided. Furthermore, the low
frequency ultrasound waves used in the method energize the drug and
cause penetration of the drug below the surface of the tissue, due
to acoustic pressure, microcavitation, etc. Finally, the bacteria
killing method is effective when applied to the surface whether the
liquid or powder sprayed is a drug (an antiseptic or antibiotic),
oil, saline, distilled water, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of an ultrasonic wound
treatment system according to the present invention.
[0015] FIG. 2 is a lateral schematic view of an ultrasonic sprayer
according to the present invention.
[0016] FIG. 3 is a partly cross-sectional view of an ultrasonic
sprayer according to the present invention.
[0017] FIG. 4a is a detailed view of the sprayer illustrated in
FIG. 3 for spraying liquid from a radiation surface.
[0018] FIG. 4b is a detailed view of the sprayer illustrated in
FIG. 3 for spraying liquid from a side (radial) surface.
[0019] FIG. 5 is a cross-sectional front view of a distal end of an
ultrasonic transducer when liquid is delivered to the side or
radiation surface of the transducer tip from 360.degree. along its
perimeter.
[0020] FIG. 6 is a variation of FIG. 4b illustrating the spraying
effect by changing the angle between the ultrasound instrument and
horizontal line from 0.degree. to 90.degree..
[0021] FIGS. 7a-7g are each a front cross-sectional view of an
ultrasound tip configuration.
[0022] FIGS. 8a-8i are each an enlarged side view of a different
modification of a tip end shape of the ultrasonic sprayer according
to the present invention.
[0023] FIGS. 9a, 9b, and 9c represent cross-sectional, distal, and
lateral views, respectively, of the top of an ultrasonic sprayer
having a slot, groove, or thread.
[0024] FIG. 10 is a schematic representation of a method of
delivery of ultrasonic energy delivered through a gaseous medium,
accordance with another embodiment of the present invention.
[0025] FIG. 11 is a plot of experimental results achieved upon
delivering ultrasound energy substantially through a gaseous medium
to a wound in accordance with the present invention.
DETAILED DESCRIPTION
[0026] The device of the invention that produces a spray is
characterized by means for first delivering the liquid to a lateral
surface of an ultrasonic transducer tip adjacent to a free end
surface such that the liquid is pulled to the free end surface by a
vacuum (negative pressure) created by the ultrasound waves on the
free end surface of the transducer tip. This effect can be achieved
while the angle between the ultrasound instrument and the
horizontal is modified up to 90.degree.. (This acoustical effect of
delivering liquid from radial side of a tip to the free end was
discovered by the inventor of this invention and is called the
"Babaev effect".) This effect occurs when liquid is delivered to
the radial surface of a transducer tip about its perimeter, up to
360.degree. about its perimeter, e.g. from the top, side, bottom,
etc.
[0027] For the above purpose the device can have a so-called nozzle
constructed from steel (non-disposable) or plastic (disposable)
with a suitable valve design. The nozzle allows delivery of liquid
to the lateral surface of the transducer tip or directly to the
distal side (radiation surface) of the ultrasound transducer, for
enabling the transducer to act as a sprayer or atomizer.
[0028] One of the major advantages of the invention is the
uniformity of the spray particles generated. Because liquid or
powder is sprayed from a solid radiation surface, there is
substantial uniformity of particle size, about 90% or greater, such
as from about 90 to 96%. It is provided that the distal radiation
surface is driven with constant frequency and amplitude to create
the spray. It is also provided that the frequency and/or amplitude
can be modulated during treatment and that the distal radiation
surface is driven with a sinusoidal, rectangular, trapezoidal or
triangular wave form.
[0029] The step of producing the spray can further include
operating the transducer to produce ultrasonic waves having a
frequency of from about 18 kHz to 10,000 MHz. Frequencies below 18
kHz, i.e., from about 1 to 18 kHz, can be used as well; however,
this lower range is less desirable because this range of sound wave
can be uncomfortable to the patient and operator (without ear
protection or the like). Frequencies in the range of from about 30
to 100 kHz are used in some embodiments, and frequencies of about
40 kHz are used in one embodiment.
[0030] The separation distance between the free end surface of the
transducer and the surface or object to be sprayed should be a
"non-contact" distance of at least 0.1 in. (2.5 mm). In one
embodiment, the separation distance is from about 0.1 in. (2.5 mm)
to 20 in. (51 cm), for example from about 0.1 in. (2.5 mm) to 5 in.
(12.7 cm). The liquid or powder to be sprayed can be any
appropriate carrier such as water (regular or distilled), saline
solution, or oil to be applied to tissue (i.e., biological tissue
or non-biological tissue), such as a vegetable, peanut, or canola
oil, optionally with a soluble pharmaceutical, e.g., an antibiotic,
antiseptic, conditioner, surfactant, emollient, or other active
ingredient. The pharmaceutical or the like can be present in a
concentration sufficiently low to be soluble but high enough to be
effective for the intended purpose.
[0031] It is within the scope of the invention that the liquid to
be sprayed could include a mixture of two or more immiscible
liquids or a heterogeneous mixture of a solution and small
particles. It is also within the scope of the invention that the
spray could include particles, such as powder, and that the liquid
in the reservoir could include powder.
[0032] The spray produced according to the invention is directed to
the object, surface, or tissue to be sprayed for the time and
frequency required for accomplishing a particular purpose or
treatment. It is believed that a minimum length of spray of at
least one second will be required; however, the length or duration
of the spray could be from about one second to as much as a minute
or more, even 30 minutes. Numerous factors or circumstances, such
as, for example, the area to be sprayed (e.g., the size of a
wound), the volume rate of spray produced, the concentration of
active ingredient, etc., will impact upon the duration and/or
frequency of the spraying. Spraying could be required from one or
more times daily to as little as two or three times a week or
month.
[0033] According to embodiments, ultrasonic waves are applied to a
wound without establishing contact, directly or indirectly, between
the ultrasonic transducer and the wound. For example, surfaces of
the human body especially suited for treatment in accordance with
the method of the present invention include infected and
inflammatory situations in open wounds, including trauma or gun
shut wounds, fire and chemical burns.
[0034] In addition, embodiments of the method can be suited to
directing a spray into orifices or other body crevices that are
difficult to access.
[0035] Wound treatment according to the method and apparatus of the
present invention has several advantages. First, this method
topically applies medicines such as liquid antibiotics to the wound
surface without the need to contact infected, inflamed or painful
tissue with an instrument. And second, a significant bactericidal
effect occurs when a wound surface is sprayed using the method of
the present invention.
[0036] Moreover, aside from the bactericidal effect and advantages
of non-contact treatment, it has been found that using the method
of the present invention gave a significant reduction in volume
used of liquid medicine used as compared with traditional methods
for wound treatment. Similarly, this allows for precise dosage of
the sprayed liquid to permit a user, such as a physician, to
administer the desired volume of liquid at a desired rate and
duration.
[0037] It has been found that the method of the present invention
decreases healing times for inflammatory and purulent infected
wounds from about 1.5 to 3 times faster than traditional methods.
This effect results from a bactericidal, blood flow increasing and
mechanical cleansing effect of the atomized spray particles, which
have ultrasound energy due to the ultrasonic waves. The spray
mechanically scrubs the surface of tissue to remove dirt, dead
tissue, and purulent buildup on the tissue surface. The mentioned
healing effect also results of energized and highly activated
antibiotics, and drug penetration into the tissue surface up to 0.5
mm in depth under influence of ultrasound waves.
[0038] Additionally, a combination of the low frequency ultrasonic
waves and the sonicated medicines (highly activated by ultrasonic
energy) destroys the surface bacteria, resulting in a higher
disinfecting property of sonicated liquids as compared to
ordinarily applied liquids.
[0039] The spray of the present method also stimulates healthy cell
growth to aid in granulation and epithelization of the healing
tissue.
[0040] Other applications of the invention can be directed to
non-medical uses such as cleansing, sterilizing and coating
surfaces of objects and food.
[0041] The method of the present invention offers an approach that
may re-establish use of some traditional antibiotics and establish
a method for fighting bacteria without antibiotics when necessary.
The effect of the method of the present invention in highly
activating antibiotics may allow some traditional antibiotics to
overcome bacteria which have become resistant to that antibiotic.
Moreover, independent of the sonication effect of the antibiotics,
the low frequency ultrasonic waves applied in accordance with the
method of the present invention physically destroy bacteria. The
combination of the highly activated antibiotics and of the low
frequency ultrasonic waves in accordance with the method of the
present invention produce a strong bactericidal effect not found in
mere topical application or oral ingestion of antibiotics. This
combined effect has been shown to significantly increase the
healing of purulent infected wounds.
[0042] The present method also provides a system of non-contact
drug delivery without use of a compression sprayer system. This
simplifies the design of a non-contact drug delivery sprayer and
reduces the weight of the sprayer. More importantly, not using
compression to propel the atomized particles preserves the
ultrasound energy carried by the spray particles.
[0043] Delivery of ultrasound energy in accordance with the present
invention has been proven to destroy bacteria by action of the
ultrasonic waves and by highly activated liquid medicines applied
to the tissue.
[0044] The method of the present invention provides a method of
compressionless non-contact drug delivery.
[0045] The invention is better appreciated by making reference to
the drawings. In FIG. 1, an ultrasonic treatment system 2 includes
an ultrasound generator 4, connected to an ultrasound transducer 6
by a cable 8. The generator 4, which is conventional, may have a
front panel 10 with a power button 12, a timer 14, a control button
16, a display 18, and one or more jacks 20, for example, for
connecting a footswitch. A nozzle 22 having a liquid reservoir 24
with a valve 26 is attached to the distal portion of transducer 6.
Arrows 28 represent the direction of the spray produced.
[0046] FIG. 2 is a simplified representation of an ultrasonic
device and spray according to the invention. Transducer 6 has a
distal transducer tip or horn 30. Liquid from a liquid reservoir 32
flows through a valve 34 to a position adjacent the distal
radiation surface 36 of a horn 30. Transducer 6 is attached to an
ultrasound source via cable 8. A liquid mist is directed in the
direction of arrows 38 to target tissue or surface 40 (wet
approach).
[0047] FIG. 3 is an enlarged, partly cross-sectional view of a
section of FIG. 1 illustrating a spray created by the device
according to the method of the present invention. This device is a
modification and implementation of a device disclosed in U.S. Pat.
No. 5,076,266, which is incorporated herein by reference. As can be
seen in more detail in FIG. 3, nozzle 22 surrounds ultrasound horn
30. Also, liquid reservoir 32 has a valve 34 positioned between
reservoir 32 and the distal surface 36 of ultrasonic horn 30. A
conical spray pattern of liquid particles 42 is directed at a
surface or tissue 44 of a target. This configuration is effective
to spray liquid onto a surface and to deliver ultrasonic waves to
that surface, such as, for example, the surface of a wound.
[0048] Valve 34 allows liquid to flow to distal tip 36 as drops or
as a continuous flow through gap 46. Valve 34 may be located
anywhere, including between reservoir 32 and horn 30. Mechanical
movement of the horn 30 in the direction x-x causes liquid to flow
to the distal end of radiation surface 36.
[0049] FIG. 4(a) is a view of the ultrasonic sprayer as used in
accordance with the method of the present invention for spraying
liquid 48 directed to distal end (radiation surface) 36.
[0050] FIG. 4(b) is a view of the basic spraying method from side
(radial) surface of the tip based on the Babaev effect. In this
example, liquid or drug directed to the radiation surface 36 of
ultrasound horn 30 becomes sonicated (ultrasonically energized),
after being pulled forward by negative pressure (vacuum) created by
ultrasound waves and sprays.
[0051] As shown in FIG. 5, liquid is delivered to the side of
radiation surface 36 of transducer horn 30 about the perimeter of
radiation surface 36, up to 360.degree. about its perimeter, e.g.
from the top, side, bottom, etc.
[0052] In the embodiment of the invention shown in FIG. 6, a
partial section of transducer horn 30 is elevated from the
horizontal up to 90.degree.. Due to the Babaev effect, liquid 48
still travels to radiation surface 36.
[0053] The ultrasound tip or horn may have a regular or irregular
lateral cross-section, including circular, oval, elliptical,
rectangular, trapezoidal, or a combination thereof. For example,
FIGS. 7(a) to 7(g) are each a view of a cross-section of an
ultrasound tip or horn. Also, the distal end shape of the
ultrasound tip or horn longitudinal cross-section may vary, and may
be rectangular, elliptical, oval, spherical, conical, curved,
stepped, with chamfer, etc., as shown in FIGS. 8(a) to 8(n), which
are each an enlarged view in section of a different, exemplary
modification of a tip of the sprayer as used in accordance with the
method of the present invention. The shape can be rectangular in
one embodiment, because radiation beams from ultrasound tip surface
are substantially fully directed to the target (wound). With the
spherical, elliptic and oval (FIG. 8(e)) form or shape of the
distal end, radiation beams are focused at a focal point. However,
with other forms or shapes of the distal end, radiation beams are
spread, thus partially reaching the target.
[0054] Radial side surface of the distal end of the tip may have a
slot (groove) or thread for liquid to be directed to the radiation
surface (FIGS. 9a-9c).
[0055] FIGS. 9a to 9c are each a view of a radial side surface of
the distal end of the tip which has a slot (groove) 19 or thread 20
for liquid to be directed to the radiation surface.
[0056] The ultrasonic energy delivered has an intensity capable of
providing a therapeutic effect to the wound 40, exerting acoustic
pressure and/or causing micro-cavitation. Acoustic pressure refers
to a force that can be felt which is exerted through air between
the transducer and the tissue being targeted. Microcavitation
refers to the formation and pulsation of gas or vapor filled
microscopic bubbles in fluids as a result of ultrasonically induced
and regularly repeated pressure changes. Advantages to micro
cavitation include the creation of acoustic streaming which is a
steady circulation of fluid in blood vessels induced by ultrasound
radiation force.
[0057] In one embodiment, the amplitude achieved by the ultrasonic
energy is at least 3 microns, and at least 10 microns in one
embodiment. In embodiments, the frequency used is in the range of
20 kHz-50 MHz, wherein a range is 20-200 kHz in some embodiments,
another range is 20-40 kHz in embodiments and a value is 40 kHz in
embodiment, wherein the lower limit of the frequency used is
outside of the human hearing range in embodiments.
[0058] Furthermore, it is advantageous in embodiments to use a
radiation surface 36 having a shape and size selected to achieve
delivery of the ultrasonic energy to the wound where the delivered
ultrasonic energy has an intensity capable of providing a
therapeutic effect to the wound. Selection of the shape and size of
the radiation surface 36 in combination with selection of the
frequency and amplitude of the ultrasonic energy used is
advantageous in achieving delivery of the ultrasonic energy to the
wound wherein the ultrasonic energy has an intensity capable of
achieving a therapeutic effect to the wound. In embodiments, the
radiation surface 36 has a relatively large diameter. Actual
selection of the diameter is dependent upon the frequency and
amplitude selected. Furthermore, the shape of the radiation surface
36 is selected from one of flat, concave, convex, or a combination
thereof, and from the configurations shown in FIGS. 8a-8i, or a
combination thereof.
[0059] In another embodiment, ultrasonic energy is delivered to the
wound without the use of the spray, i.e., the ultrasonic energy is
delivered through a medium other than a spray, including a gaseous
medium, such as pure air, e.g., ambient air, where the ultrasound
transducer 6 is positioned at a non-contact distance from the wound
for providing a therapeutic and beneficial effect. The ultrasound
waves, even without the use of a spray, destroy surface bacteria
and stimulate health cell growth. This method of wound treatment is
particularly advantageous on wounds for which contact with the
wound should be avoided.
[0060] With reference to FIG. 10, an ultrasonic treatment system 2'
is shown including an ultrasound generator 4' connected to an
ultrasound transducer 6' by a cable 8' for generating ultrasound
energy. Transducer 6' has a radiation surface 36' from which the
ultrasound energy is emitted and directed to wound 40'. The
generator 4', which is conventional, may have a front panel 10'
with a power button 12', a timer 14', a control button 16', a
display 18', and one or more jacks 20', for example, for connecting
a footswitch. Arrows 100 represents the direction of ultrasound
energy generated and directed toward wound 40'. Unlike the above
embodiments, a liquid or powder is not contacted with the
ultrasonic transducer for generating a spray and directing it to
the wound 40'. The ultrasonic energy is delivered through a medium
other than a spray, including a gaseous medium, such as pure air
("dry" approach). A horn of the transducer 6' may be configured in
accordance with the embodiments shown in FIGS. 7a-g, 8a-i and/or
9a-c.
[0061] In one embodiment, wherein the ultrasonic energy is
delivered to the wound 40' through a gaseous medium, such as pure
air, for achieving a therapeutic effect at the wound 40', the
frequency of the ultrasonic energy generated is selected to be a
low frequency. By using a low frequency, a particular or
predetermined amplitude for the generated ultrasonic energy is
achieved, which is capable of being delivered to the wound with an
intensity capable of providing a therapeutic effect to the wound
40', exerting acoustic pressure and/or causing micro-cavitation. In
embodiments, the amplitude achieved by the ultrasonic energy is at
least 3 microns, such as at least 10 microns. In embodiments, the
frequency used is in the range of 20 kHz-50 MHz, wherein a range is
20-200 kHz in embodiments, 20-40 kHz in other embodiments, and a is
40 kHz in one embodiment, wherein the lower limit of the frequency
used is outside of the human hearing range in embodiments.
[0062] Furthermore, it is advantageous to use a radiation surface
36' having a shape and size selected to achieve delivery of the
ultrasonic energy to the wound where the delivered ultrasonic
energy has an intensity capable of providing a therapeutic effect
to the wound. Selection of the shape and size of the radiation
surface 36' in combination with selection of the frequency and
amplitude of the ultrasonic energy used is advantageous in
achieving delivery of the ultrasonic energy to the wound wherein
the ultrasonic energy has an intensity capable of achieving a
therapeutic effect to the wound. In embodiments, the perimeter of
the radiation surface 36' is round, rectangular, elliptical, oval,
spherical, conical, curved, stepped, with chamfer, etc., or a
combination thereof, as shown in FIGS. 8(a) to 8(n), and has a
relatively large diameter. Actual selection of the diameter is
dependent upon the frequency and amplitude selected. Furthermore,
the shape of the radiation surface 36' is selected from one of
flat, concave, convex, and a combination thereof.
[0063] With respect to FIG. 11, results are shown of
experimentation at Celleration Acoustic Laboratory, Eden Prairie,
Minn. Ultrasonic energy having an intensity capable of providing a
therapeutic effect was delivered through air (no spraying of liquid
or powder) to a wound using an ultrasound transducer positioned at
a non-contact distance from the surface of the wound, as shown by
FIG. 10. The ultrasonic energy was generated at a frequency of 40
kHz and an amplitude of 61 microns. The transducer radiation
surface was flat, rounded and had a diameter of 1 cm. Hydrophone
model number PVDF-Z44-1000 and hydrophone amplifier model number
Al7db, both manufactured by ONDA Corporation, Sunnyvale, Calif.,
were employed, using an amplifier gain of 7.44. As shown, with the
transducer positioned at a distance of between 2.5 mm and 38 mm
from a wound, ultrasonic energy was delivered to the wound having
an intensity capable of providing a therapeutic effect to the
wound; the intensity being within the range of from 0.1 W/cm.sup.2
to 10 W/cm.sup.2.
[0064] With respect to FIGS. 10-11, the ultrasound energy is
delivered to the wound or tissue being treated through a medium
other than a spray, including a gaseous medium, such as pure air,
e.g., ambient air, including without the use of the spray.
Accordingly, the ultrasound energy is delivered to the tissue
through a substantial expanse of a substantially purely gaseous
medium, such as ambient air. In embodiments, the transducer can be
positioned at a non-contact distance from the tissue, where the
space between the transducer and the tissue through which the
ultrasound energy is delivered is an expanse of a substantially
purely gaseous medium spanning a distance of at least about 0.1 in.
(2.5 mm) from the transducer to the tissue. In embodiments, the
distance spanned is from about 0.1 in. (2.5 mm) to 20 in. (51 cm),
and is from about 0.1 in. (2.5 mm) to 5 in. (12.7 cm) in some
embodiments.
[0065] The embodiment shown in FIGS. 2-6 may further be used for
delivering ultrasound energy to the skin without the use of a spray
by not providing a liquid within the reservoir 32 so that liquid
does not flow to the radiation surface 36, or by selectively
controlling delivery of liquid from the reservoir to the radiation
surface 36 in accordance with one or more requests from an operator
and/or a control module. The operator may make a request via a
selection device which may be mechanical and/or electrical, e.g., a
button, trigger, lever and/or user interface. The request may be
processed mechanically and/or electrically (by analog and/or
digital processing) for mechanically controlling flow of the
liquid, such as by controlling the valve 34 to remain open or
closed or sequentially open and close, in any order. Accordingly,
non-contact ultrasound treatment without a spray may be provided to
tissue using either the embodiment shown in FIGS. 1-6 or the
embodiment shown in FIG. 10.
[0066] As described further below, the reservoir may be provided in
a device separate from the transducer and the spray may be
generated and delivered from another device separate from the
transducer, where the separate device may be detached from or
attached to the transducer. The spray from the separate device may
be a spray generated and delivered by another transducer or by a
device that does not use ultrasound energy. Similar to the
embodiment described with respect to FIGS. 1-6 in which the spray
is delivered simultaneously with delivery of the ultrasound energy,
the spray delivered from a separate device may be delivered
simultaneously with delivery of the ultrasound energy.
Alternatively, the spray may be delivered prior to delivery of the
ultrasound energy, as described further below. Furthermore, a
treatment may include a series of continual and/or intermittent
treatments, wherein individual treatments of the series of
treatments are selected from the group consisting of: delivery of
ultrasound energy with the use of a spray, i.e., the wet approach
as described with respect to FIGS. 1-6; and delivery of ultrasound
energy through a medium other than a spray (i.e., a gaseous
medium), i.e., the dry approach as described with respect to FIG.
10, with the two or more steps performed in any order. Accordingly,
non-contact ultrasound treatment with or without a spray may be
provided to tissue using either using the embodiment described with
respect to FIGS. 1-6 or the embodiment shown in FIG. 10.
[0067] The liquid or powder to be sprayed (via the reservoir 32,
valve 34 and radiation surface 36 shown in FIGS. 1-6 or via a
separate device) may be an analgesic, such as for use as a local
anesthetic, such as prior to a dental procedure, suturing, or other
invasive or noninvasive procedure or for relief of pain. The
analgesic is sonicated, providing a more immediate effect, a more
potent effect, further penetration into the skin, improved
precision of dosage, and a more targeted affect for minimizing
effects to untargeted tissue. Moreover, independent of the effect
of the sonicated analgesic, the low frequency ultrasonic waves
applied in accordance with a method of the present invention, such
as through the medium of a spray formed from a saline solution,
provide an analgesic effect. The combination of the sonicated
analgesic and of the low frequency ultrasonic waves in accordance
with a method of the present invention produce a strong local
anesthetic effect not found in mere topical application of
analgesics.
[0068] Another embodiment of a method of the invention includes the
step of providing a substance, such as a medicament and herein
referred to as medicament, for application of the medicament to
tissue, and delivering ultrasound energy to the medicament as it is
applied or once it is applied and to the tissue using the
embodiment shown in FIGS. 1-6 or the embodiment shown in FIG. 10,
and the amplitude, frequency, non-contact distance and other
parameters for the ultrasound energy, generator and transducer
described above. The ultrasound energy is delivered by a
non-contact delivery (i.e., without contacting the transducer 6 or
6' to the tissue) to the tissue, as described above, and may be
delivered through a spray or without a spray, e.g., by delivering
the ultrasound energy through a medium other than a spray, such as
ambient air, gas, etc. The medicament is, for example, an
antibiotic, an ointment, cream, gel, liquid, salve, oil, saline
solution, distilled, non-distilled and/or boiled water, powder,
spray, antibacterial agent, antiseptic agent, insulin, analgesic
agent, conditioner, surfactant, emollient, or other active
ingredient, or a combination thereof.
[0069] The medicament may be applied directly to the tissue before
the ultrasound energy is delivered to the tissue, and/or during the
delivery of the ultrasound energy to the tissue. The medicament may
be provided within at least one container from which the medicament
is applied to the tissue, where the container is in contact with
the tissue, proximate the tissue and/or spaced from the tissue and
oriented for directing the medicament at the tissue. The container
may have a permeable wall(s) through which the medicament may pass
directly to or towards the tissue, manually, automatically and/or
mechanically, and/or through which the ultrasound energy may
penetrate. The container may be integrated with or separated from
the housing of the transducer 6 or 6'. Furthermore, the medicament
may be applied below the tissue in addition to or instead of to the
surface of the tissue.
[0070] The various medicaments and methods for applying the
medicament to the tissue may be used sequentially in any
combination or sequence in conjunction with application of the
ultrasound energy (delivered with and/or without the spray, or
sequentially with and without the spray in any sequence). The
sequence may include wait periods during which the ultrasound
energy is not applied. Specifically, a treatment may include a
series of treatments, wherein individual treatments of the series
of treatments are selected from the group consisting of: the
treatment including the steps of delivering ultrasonic energy from
a non-contact distance to the tissue simultaneous with delivery of
a spray to the tissue, wherein the ultrasonic energy has an
intensity capable of penetrating the tissue to a beneficial depth
to provide a therapeutic effect to the tissue and sonicating the
spray for causing the medicament to penetrate the tissue to a
beneficial depth to provide a therapeutic effect to the tissue; the
treatment including the steps of delivering ultrasonic energy from
a non-contact distance to the tissue through a substantial expanse
of a substantially purely gaseous medium to the tissue, wherein the
ultrasonic energy has an intensity capable of penetrating the
tissue to a beneficial depth to provide a therapeutic effect to the
tissue; and the treatment including the steps of the method of the
invention, wherein a different medicament is applied.
[0071] Delivery of the ultrasound energy to the medicament and to
the tissue energizes the medicament via sonication and causes
penetration of the medicament into the tissue for providing an
enhanced therapeutic effect to the tissue. Further, the delivery of
the ultrasound energy causes exertion of acoustic pressure. The
sonicated medicament and the combination of the sonicated
medicament and the low frequency ultrasound waves each provide at
least advantages similar to the advantages provided by the
sonicated spray and the combination of the sonicated spray and low
frequency ultrasound waves. Such advantages include increasing
potency of the medicament, obtaining more immediate results,
decreasing the volume of the medicament used relative to a volume
used for a comparable treatment using traditional methods for
achieving the same effect, increased precision of dosage of the
medicament, re-establishment of traditional antibiotics to which
bacteria have become resistant and deeper penetration into the
tissue.
[0072] The substance may be applied to surfaces other than tissue
for non-medical applications, such as cleansing, sterilizing and
coating surfaces of objects and food.
[0073] The preceding specific embodiments are illustrative of the
practice of the invention. It is to be understood, however, that
other expedients known to those skilled in the art or disclosed
herein, may be employed without departing from the spirit of the
invention or the scope of the appended claims.
* * * * *