DEVICES AND METHODS FOR TREATMENT OF DERMATOLOGICAL CONDITIONS
20230046154 · 2023-02-16
Inventors
Cpc classification
A61B2018/0293
HUMAN NECESSITIES
A61B2090/033
HUMAN NECESSITIES
A61B2018/00916
HUMAN NECESSITIES
A61B2018/0047
HUMAN NECESSITIES
International classification
Abstract
Embodiments described herein are directed to a system for providing alternating freeze and thaw cycles. The system includes a controller, a vessel for holding a working fluid, a pressure generator, a cooler, a cooler heat exchanger, a heater, a heater heat exchanger, a check valve, and a treatment instrument. In some embodiments, the treatment instrument includes a distal end, a proximal end, a connecting portion adjacent to the proximal end, a needle element adjacent the distal end, a handle portion disposed between the proximal and distal end, and a depth-limiting element to limit an injection depth of the needle element.
Claims
1. A system for providing alternating freeze and thaw cycles, the system comprising: a controller; a vessel for holding a working fluid; a pressure generator operatively connected to the vessel for pressurizing the working fluid to a predetermined pressure; a cooler for cooling a working fluid; a heater for heating the working fluid, wherein the heater is arranged in parallel with the cooler; a three-way valve located between the vessel and the cooler and the heater; a treatment instrument comprising: a distal end, a proximal end, a connecting portion adjacent the proximal end, a needle element adjacent the distal end, a handle portion disposed between the proximal and distal end, and a depth-limiting element to limit an injection depth of the needle element; and a check valve in fluid communication with an output of the treatment instrument.
2. The system of claim 1, wherein the controller is operatively connected to the vessel, the pressure generator, the cooler, the heater, the three-way valve, the check valve, and the treatment instrument, wherein the pressure generator is operatively connected to the vessel, and wherein the vessel is in fluid communication with the cooler, the heater, the three-way valve, and the check valve.
3. The system of claim 1, wherein the pressure generator comprises a piston for raising a pressure of the system.
4. The system of claim 1, wherein the pressure generator comprises an external gas pressure source.
5. The system of claim 1, wherein a length of the needle element of the treatment instrument extending from the depth limiting element is adjustable.
6. The system of claim 1, further comprising a working fluid.
7. The system of claim 6, wherein the working fluid is selected from the group consisting of alcohol ethanol, octafluoropropane, diethyl ether and propylene glycol.
8. The system of claim 1, wherein the treatment instrument includes a proximal section comprising: a freeze lumen for delivering cold working fluid to the needle element; a thaw lumen for delivering warm working fluid to the needle element; and a return lumen for delivering cold working fluid and warm working fluid from the needle element.
9. The system of claim 8, wherein the proximal section of the treatment instrument includes thermal insulation about an exterior thereof.
10. The system of claim 1, wherein the pressure generator is operatively connected upstream to the cooler and heater, and wherein the cooler and heater are connected in parallel downstream of the pressure generator and upstream of the treatment instrument.
11. The system of claim 1, wherein the three-way valve is downstream of the pressure generator.
12. The system of claim 1, wherein the three-way valve is upstream the cooler and heater.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above-mentioned aspects, as well as other features, aspects, and advantages of the present technology will now be described in connection with various embodiments, with reference to the accompanying drawings. The illustrated embodiments, however, are merely examples and are not intended to be limiting. Throughout the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Note that the relative dimensions of the following figures may not be drawn to scale.
[0017]
[0018]
[0019]
[0020]
[0021]
[0022]
[0023]
[0024]
[0025]
[0026]
[0027]
[0028]
[0029]
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
DETAILED DESCRIPTION
[0036] The disclosed and described technology relates to cryotherapy systems, devices and methods to treat various skin conditions.
The System and Treatment Instruments:
[0037] The system employs an open thermodynamic cycle and uses a cryogen that is a high-density fluid with a freezing temperature below the treatment temperature. The fluid should not be hazardous (such as toxic, explosive, etc.) and must have a high density in order for it to be an efficient thermal agent. The fluid should also have a low viscosity such that it can flow through small channels and small diameter lumens within the treatment device without a significant pressure gradient and/or viscous heating. Sample high density fluids for use in the present system are included in Table 1.
TABLE-US-00001 TABLE 1 Equi- Freezing librium Viscosity Tem- Pressure (μ) at Chemical perature at 25° C. Density −25° C. Fluid Formula (Celsius) (MPa) (kg/m.sup.3) (Pa .Math. s) Alcohol Ethanol C.sub.2H.sub.5OH −114° Stable 890 4.0 × 10.sup.−3 Octafluoropropane C.sub.3F.sub.8 −150° .087 1500 3.6 × 10.sup.−4 Diethyl Ether (C.sub.2H.sub.5).sub.2O −116° .100 750 2.0 × 10.sup.−4 Propylene Glycol C.sub.3H.sub.8O.sub.2 −59° Stable 1050 >0.04
[0038] Depicted in
[0039] Initially, the working fluid is maintained at ambient temperature (TA) and an elevated pressure (P.sub.IN). Under these conditions, the fluid should be well within its high-density phase. Some examples of a fluid's high-density phase include the liquid phase and/or supercritical phase, which is where the fluid has the properties of both a liquid and a gas and which typically occurs above the liquid's critical point, i.e., above the liquid's critical temperature and critical pressure.
[0040] An embodiment of the cryotherapy system 10 is depicted in
[0041] For example, the pressure generator can be a mechanical piston system 18 that includes a piston head 20, a connecting rod/means 22 and at least one compression ring/gasket 24. The piston head 20 and connecting rod 22 can be driven by, for example, an electrical (stepper) motor. The pressures necessary to run the system can also be generated and maintained with the use of a closed volume system that contains the working fluid. As depicted in
[0042] Because the system has a dual function of freezing and thawing, a dual fluid flow is included. This is achieved with the use of a three-way valve 36 as depicted in
[0043] As can be seen in
[0044] Also included with the system 10 is a treatment instrument 48 (for example, a needle device) for insertion into skin. The treatment instrument 48 connects to the system through a three-port hermetic connector that connects the cold fluid supply line, warm fluid supply line, and a return fluid line from the system 10 to the treatment instrument 48. In some embodiments, multiple cold fluid supply lines and/or multiple warm fluid supply lines and/or multiple return fluid lines may be used.
[0045] Depicted in
[0046] As shown in
[0047] In some embodiments, the needle 50 length can range from approximately 1.0 mm to approximately 10.0 mm and extends form a handle portion 70 that, as depicted in
[0048] In some embodiments, the disk-like section 72 may include a heating element such as, for example, an electrical heater, that is used to prevent freezing of the upper most layer of skin (epidermis) by maintaining the temperature at a safe level, for example, approximately 30° C. to 42° C. The disk-like section 72 may also include a thermal sensor to monitor the temperature of the epidermis temperature in order to control the temperature of the heating element.
[0049] Following is a thermodynamic analysis for a needle 50 as depicted in
[0050] For the dimensions, assume a standard botox needle, which is 27 gauge. Such a needle can be constructed as follows:
[0051] Needle shaft (stainless steel): D.sub.N=0.41 mm; D.sub.O=0.25 mm
[0052] Inner tubing (polyimide): d.sub.1=0.13 mm; d.sub.Ø=0.10 mm
[0053] Annulus space will have its hydraulic diameter (d.sub.H) as follows:
d.sub.H=D−d.sub.1=0.12 mm OR d.sub.H≅d.sub.Ø
[0054] Because the preferred working fluid is octafluoropropane, assume:
TFR=−25° C., which leads to μ=3.6×10.sup.−4 Pa s
[0055] Assume laminar flow, for ΔP=P.sub.IN−P.sub.OUT=100 psi (7×10.sup.5 Pa)
[0056] The corresponding Reynold's Number:
[0057] Accordingly, the flow is very laminar.
[0058] Cooling power=power required to warm up the needle to 0° C.:
[0059] This amount of power is more than adequate for all skin/fat treatments discussed herein.
[0060] In some embodiments, the system may include multiple treatment instruments, which may be operated independently of one another or which may be operated synchronously. Accordingly, in these embodiments, the system will include multiple connection ports/supply hoses.
[0061] As depicted in
[0062] As depicted in
[0063] In order to regulate the temperature for the freezing and thawing cycles, either of the following methods can be used. The freezing temperature (T.sub.FR) can be maintained by setting the cooler 44 temperature to some constant value, −25° C., for example, and regulating the fluid flow by changing pressure P.sub.IN of the working fluid flowing from the container 14 to the cooler 44. Similarly, the thawing temperature (T.sub.TH) can be maintained by setting the heater 46 temperature to some constant value, 38° C., for example, and regulating the fluid flow by changing pressure P.sub.IN of the working fluid flowing from the container 14 to the heater 46. Alternatively, the freezing temperature (T.sub.FR) can be maintained by setting the pressure P.sub.IN of the working fluid flowing from the container 14 to the cooler 44 to a constant pressure and changing the temperature of the cooler 44. Similarly, the thawing temperature (T.sub.TH) can be maintained by setting the pressure P.sub.IN of the working fluid flowing from the container 14 to the heater 46 to a constant pressure and changing the temperature of the heater 46. Either of the above methods may be used or a combination of the above methods may be used to regulate T.sub.FR and T.sub.TH.
[0064] The system 10 may also include a plurality of sensors such as pressure gauges 78 and thermistors that are used to monitor operation of the system 10 and to control the operating parameters for treatment procedures. Information obtained from these sensors can be displayed on the display 76 so that a user has real-time operating data for the system.
[0065] In some embodiments, the system 10 includes a flow meter in the working fluid cooling/freezing flow path 38 in order to measure fluid flow through the system and hence the system's cooling power.
[0066] Operation of the system 10 will now be described. The working fluid 12 is first added to container 14, where it is then pressurized by the pressure generator 16 to a predetermined pressure (P.sub.IN). Next, for a freeze cycle, the three-way valve 36 is actuated to open the flow path 38 to the cooler 44. The working fluid 12 is then delivered to the heat exchanger 42 for the cooler 44 where the working fluid 12 is cooled to a pre-set treatment freeze temperature (T.sub.FR). Once the working fluid 12 is cooled to T.sub.FR, the working fluid 12 is delivered the thermally insulated hose 58 to the treatment instrument 48, which is inserted into the target tissue to be cooled/frozen. Because the needle 50 of the treatment device 48 is in thermal contact with the target tissue, heat is removed from the target tissue by the flowing, cooled working fluid, thereby cooling/freezing the target tissue. Within the treatment device 48, the working fluid 12 flows into freeze channel/lumen 62, into the delivery channel/lumen 65, into to the flow chamber 53, then exits the flow chamber 53 by flowing into the return channels/lumens 66 and then exits the treatment device 48 through the return channels/lumens 66. Upon exiting the treatment device 48 through the return channels/lumens 66 and return lumen in the thermally insulated hose 58, the return flow of working fluid, which is now at a higher temperature (T.sub.OUT) and lower pressure (P.sub.OUT) than it was before flowing through the treatment instrument 48, is delivered back to the console, which houses many of the system's components, and discharged to the atmosphere via a check valve 80 that is pre-set to a certain release pressure (P.sub.C). Using a check valve with a pre-set release pressure is required in order to maintain the working fluid in its high-density state throughout the freeze cycle. The pre-set release pressure (P.sub.C) of the check valve 80 is determined by the choice of working fluid that is used in the system 10. That is, different pressures are required to be maintained for different working fluids in order to maintain the working fluids in their high-density state. It is important to note that from the time the working fluid 12 is pressurized and leaves the container 14 until the time it is discharged to the atmosphere through the check valve 80, the working fluid 12 always remains in its high density state as can be seen in
[0067] The thaw cycle is similar to the freeze cycle except that the flow path of the working fluid 12 in the system 10 is different. For the thaw cycle, the three-way valve 36 is actuated to open the flow path 38 to the heater 46. The working fluid 12 is then delivered to the heat exchanger 42 for the heater 46 where the working fluid 12 is heated to a pre-set treatment thaw temperature (T.sub.TH). Once the working fluid 12 is heated to T.sub.TH, the working fluid 12 is delivered to the thermally insulated hose 58 to the treatment instrument 48, which is inserted into the target tissue to be heated/thawed. Operation of the system 10 for all other aspects is similar to that of the freeze cycle. Again, as shown in
[0068] In another embodiment, the system can be a closed loop system. As used herein, “closed loop” means that instead of venting working fluid through a check valve to the atmosphere after it flows through the treatment instrument for either freezing or thawing, the working fluid is instead returned to the holding container for re-use by the system. This can be achieved by means of an external pump.
[0069] It is important to note that unlike prior systems (argon-based systems, for example), the cooling/freezing and warming/thawing effect in the present system does not occur at the treatment device. Instead, cooling and heating of the working fluid 12 are achieved using a dedicated cooler or heater prior to the working fluid entering the treatment device.
Treatment Methods
[0070] Treatment procedures using the disclosed and described systems and treatment devices will now be described. As previously discussed, the treatment instrument includes a sharp needle that is thin enough to be able to penetrate through the epidermal skin layer without leaving a scar behind and thick enough to expose all skin layers together or separately (epidermis 108, dermis 110 and hypodermis 112, as identified in the figures) to one or more freeze-thaw cycles. After the needle is inserted into the skin into the target tissue, a freeze cycle is begun, which can last a few seconds to few minutes, to freeze the target tissue to between approximately 0° C. to approximately −30° C. Following the freeze cycle, a thaw cycle is commenced exposing the target tissue to higher temperatures of between approximately 37° C. to approximately 45° C. in order to induce a fast heating/thawing process of the target tissue. Such freeze-thaw cycling stimulates biological effects such as the recovery of existing collagen, production of new collagen and establishment of new vasculature, all of which lead to skin rejuvenation. This biological response will be increased if this freeze-thaw cycling is repeated multiple times on the same skin area/target tissue.
[0071] This freeze-thaw cycling treatment in the dermal layer recovers existing collagen elasticity, collagen volume and collagen structure in a facial or body skin areas. Thus, the freeze-thaw cycling treatment can be applied directly to skin wrinkles or scared tissue to recover “old” collagen and reverse the aging process of the treated skin because recovering collagen elasticity, increasing collagen volume and recovering collagen structure reduces wrinkles and even causes wrinkles to disappear.
[0072] Freeze-thaw cycling in the dermal layer also promotes the production of new collagen. Because skin dermis is resistant to minor freezing injury, such as that produced by short cyclic exposure to temperatures of approximately −20° C., this procedure will result in no tissue loss or permanent damage and will heal quickly. The immediate and fast thawing of the tissue following the freeze induces this healing process, which includes cellular infiltration followed by hypothermia and edema leading to the formation of granulation tissue in which fibroblasts differentiate into myofibroblasts and damaged collagen will be replaced by new, healthy collagen.
[0073] The freeze-thaw cycling treatment in the dermal layer will also lead to the establishment of new vasculature. With aging, a progressive reduction of dermis vasculature occurs due to a reduction in the number and size of vascular vessels, which is associated with the progressive alterations of vascular wall components. These alternations advance until the function of the vessel ceases. (Bonta M, Daina L, and Mutiu G. “The Process of Ageing Reflected by Histological Changes in the Skin,” Romanian Journal of Morphology and Embryology 54 (3 Suppl.) (2013) 797-804.) The exposure of the dermal layer to the freeze-thaw cycles results in cellular infiltration, which leads to the establishment of new vasculature. New vasculature is critical to the repair process of the devitalized tissue. (Gage A. “Experimental Cryogenic Injury of the Palate: Observations Pertinent to Cryosurgical Destruction of Tumors,” Cryobiology 15 (1978) 415-25; Gage A, Greene G, Neiders M, and Emmings F. “Freezing Bone Without Excision. An Experimental Study of Bone-Cell Destruction and Manner of Regrowth in Dogs,” Journal of the American Medical Association 196 (1966) 770-74.)
[0074] Direct exposure of the dermal layer to freezing temperatures is safe as long as the treatment does not lead to tissue necrosis in the skin epidermal layer. Tissue necrosis in the dermal layer is prevented by heating the epidermal layer in the vicinity where the freezing is occurring thereby keeping this layer in a temperature range (above approximately −10° C.) which should not cause any damage to the epidermal tissue. Heating can be performed by a heating element included on the treatment instrument such as is described above with respect to the disk-like section.
[0075] In order to transform aged (skin with wrinkles, for example), unhealthy skin and/or injured skin into healthier skin that is more elastic and that has a younger appearance, the system disclosed and described herein is used to apply multiple freeze-thaw cycles along wrinkle lines 100 (see
[0076] Depicted in
[0077] As can be seen in
[0078] In another skin treatment, as depicted in
[0079] As depicted in
[0080] In order to treat: the double chin area (see
[0081] Performing freeze-thaw cycling in the hypodermal layer 112 leads to adipocyte cell reduction, which is beneficial when there is a need for local lipolysis in the hypodermis layer, for example. Treating the hypodermis as such causes adipocyte apoptosis as adipocyte cells are more sensitive to cold temperatures than the rest of the tissue in the other skin layers. (Manstein D, Laubach H, Watanabe K, Farinelli W, Zurakowski D, Anderson R. “Selective Cryolysis: A Novel Method of Non-Invasive Fat Removal,” Lasers in Surgery and Medicine 40(9) (2008) 595-604.)
[0082] In order to induce lipolysis of specific areas on the body and face, this system is used to apply freeze-heat cycle treatment to cover the area in which fat removal is desired (see
[0083] Moreover, because performing the freeze-thaw cycling treatment in the hypodermal layer can result in very accurate and local lipolysis, this treatment can also be used to treat cellulite. Cellulite is located in the subsurface—or subcutaneous layer of the skin and is made up of connective tissue and fat cells known as the septa. Cellulite forms when the structural support of the skin starts to collapse and the fat cells push through, which causes the “dimpled” look. Performing the freeze-thaw treatment in these “dimpled” skin areas, reduces the fat cells that push through the connective tissue around the septa, which results in smoother skin in these areas. Thus, as can be seen in
[0084] As previously disclosed, the freeze-thaw cycles are performed along the entire length of the needle that is inserted into the target tissue/skin area. As also previously disclosed, the length of the needle/depth of insertion and freezing temperatures will be determined based on the treatment being performed, both of which may be adjusted by the doctor performing the procedure. For example: if there is a need to apply this treatment only to the epidermis layer for sunspot treatment, the needle should penetrate only 0.5-1.5 mm into the skin as depicted in
[0085] Depicted in
[0086] In addition, because the volume of the tissue is decreased during most of the treatment procedures disclosed and described herein, the overlying skin surface area will need to be reduced as well. Accordingly, performing the freeze-thaw cycles on all layers of the skin, results in an increase in the elasticity of the dermis allowing the dermis to more easily adapt to the reduced underlying tissue volume.
[0087] The foregoing disclosure provides for embodiments of systems, devices and methods for treating skin conditions such as, for example, wrinkles, skin pigmentation, areas with excessive fat, cellulite, etc. While several components, techniques and aspects have been described with a certain degree of particularity, it is manifest that many changes can be made in the specific designs, constructions and methodology herein above described without departing from the spirit and scope of this disclosure.
[0088] It is to be understood that the embodiments of the invention described herein are not limited to particular variations set forth herein as various changes or modifications may be made to the embodiments of the invention described and equivalents may be substituted without departing from the spirit and scope of the embodiments of the invention. As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features that may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the embodiments of the present invention. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process act(s) or step(s) to the objective(s), spirit or scope of the embodiments of the present invention. All such modifications are intended to be within the scope of the claims made herein.
[0089] Moreover, while methods may be depicted in the drawings or described in the specification in a particular order, such methods need not be performed in the particular order shown or in sequential order, and that all methods need not be performed, to achieve desirable results. Other methods that are not depicted or described can be incorporated in the example methods and processes. For example, one or more additional methods can be performed before, after, simultaneously, or between any of the described methods. Further, the methods may be rearranged or reordered in other implementations. Also, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described components and systems can generally be integrated together in a single product or packaged into multiple products. Additionally, other implementations are within the scope of this disclosure.
[0090] Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include or do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments.
[0091] Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z.
[0092] Reference to a singular item, includes the possibility that there are plural of the same items present. More specifically, as used herein and in the appended claims, the singular forms “a,” “an,” “said” and “the” include plural referents unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation.
[0093] It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, if an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present.
[0094] It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, a first element could be termed a second element without departing from the teachings of the present invention.
[0095] Language of degree used herein, such as the terms “approximately,” “about,” “generally,” and “substantially” as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, “generally,” and “substantially” may refer to an amount that is within less than or equal to 10% of, within less than or equal to 5% of, within less than or equal to 1% of, within less than or equal to 0.1% of, and within less than or equal to 0.01% of the stated amount. If the stated amount is 0 (e.g., none, having no), the above recited ranges can be specific ranges, and not within a particular % of the value. Additionally, numeric ranges are inclusive of the numbers defining the range, and any individual value provided herein can serve as an endpoint for a range that includes other individual values provided herein. For example, a set of values such as 1, 2, 3, 8, 9, and 10 is also a disclosure of a range of numbers from 1-10, from 1-8, from 3-9, and so forth.
[0096] Some embodiments have been described in connection with the accompanying drawings. The figures are drawn to scale, but such scale should not be limiting, since dimensions and proportions other than what are shown are contemplated and are within the scope of the disclosed inventions. Distances, angles, etc. are merely illustrative and do not necessarily bear an exact relationship to actual dimensions and layout of the devices illustrated. Components can be added, removed, and/or rearranged. Further, the disclosure herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with various embodiments can be used in all other embodiments set forth herein. Additionally, it will be recognized that any methods described herein may be practiced using any device suitable for performing the recited steps.
[0097] While a number of embodiments and variations thereof have been described in detail, other modifications and methods of using the same will be apparent to those of skill in the art. Accordingly, it should be understood that various applications, modifications, materials, and substitutions can be made of equivalents without departing from the unique and inventive disclosure herein or the scope of the claims.