Patent Application
20190022405
The present invention relates to an apparatus and a cosmetic method for treating hyperhidrosis with light-based treatments.
Photothermal Treatment
The treatment of the human body with energy sources (such as IPL, laser, Ultrasound or RF) usually induces an increase in the temperature of selected tissues, causing cellular proteins to denature, aggregate, and lose their biological activity. This in turn leads eventually to cell necrosis and/or apoptosis. The complexity of metabolic and regulatory pathways used by living cells leads to complex mechanisms during the necrotic and/or apoptotic process as well. Some studies conclude that the lipid bilayer, and perhaps some membrane-bound ATPase enzymes, are the macromolecules most likely implicated in thermal damage. (Despa, F., Orgill, D. P., Neuwalder, J., Lee, R. C., “The relative thermal stability of tissue macromolecules and cellular structure in burn injury,” Burns 31(5), 568-577 (2005)).
In general, it is the combination of temperature levels and the exposure time to elevated temperatures that induces necrotic processes in living cells. The term “accumulated thermal dose” may be used to describe this combination. Several studies indicate that there is a correlation between cell death and the rate of delivery of accumulated thermal dose during photothermal exposure. (Michael L. Denton; Gary D. Noojin; B. Giovanna Gamboa; Elharith M. Ahmed; Benjamin A. Rockwell, “Photothermal damage is correlated to the delivery rate of time-integrated temperature”, SPIE 9706, Optical Interactions with Tissue and Cells XXVII, 97061M (7 Mar. 2016).
When targeting specific organs (e.g. sweat glands, sebaceous glands, hair follicles . . . ), the objective is to induce the tissue destruction process only in the targeted organ, while leaving the surrounding tissue intact, namely, increasing the target organ temperature to levels where necrotic processes are initiated, while maintaining surrounding tissue temperature at safe levels. There are several approaches that can be taken to accomplish that objective.
One approach is to utilize differences in absorption spectra and use of one or more specific light wave bands that are better absorbed by the targeted organ than its surrounding tissue.
Inducing the desired temperature difference can also be obtained by using the energy source in a pulsed mode. When designed properly, differences in thermal relaxation times (TRT) cause the target tissue to maintain its elevated temperature for longer time, increasing the probability of necrotic processes to occur.
Bulk heating using a continuous wave-type laser or other source can also be utilized in some cases. As mentioned above, necrotic and/or apoptosis processes are complex and different organs will require different temperature levels to initiate these processes. If a tissue damage process occurs in a specific organ at lower temperature than in the surrounding tissue, heating the tissue bulk to that temperature for long enough will eventually induce necrotic process to the target organs with potentially minimal effect on the surrounding tissue. This is likely what occurs when utilizing bulk heating for hair removal.
Sweat Glands
Sweating occurs in all humans. It is the body's way of ridding itself of wastes as well as cooling off the body. In many people, excessive, bothersome sweating is not a problem given the availability of deodorants and the availability of anti-perspirants to basically block excretion of sweat. For other people, however, sweating may be a major problem or present an embarrassing situation not resolvable by topical lotions.
Sweat glands are cutaneous appendages like hair follicles or sebaceous glands
Sweat glands are coiled tubular systems and generally fall under two types: eccrine sweat glands and apocrine sweat glands, as will be described below. Although they are usually perceived as distinct single entities, there is evidence that the coils of two eccrine glands may also occur convoluted within each other; thus, these structures might easily be mistaken as one large coil with two or more ducts to the surface.
There is a distinction between eccrine and apocrine glands, which differ one from the other in their morphology and content (sweat ingredients).
The eccrine gland consists of a single tubule ranging from about 4 to 8 mm in total length. The intra-epidermal part of the sweat gland is called the acrosyringium followed by the dermal duct with a straight and a coiled part, and a coiled, secretory portion, which is found in the deep dermis, as can be seen in
Apocrine glands are generally restricted to hairy body areas, as they open and secrete into the hair canal. For this reason, apocrine glands can be found only in the axilla, mammary, perineal and genital region. The apocrine duct is very short and can be found in close vicinity to the hair follicle, again as may be seen in
Some human sweat glands cannot be classified as either apocrine or eccrine, having characteristics of both; such glands are termed apoeccrine. (See, Wikipedia description of “Sweat Gland” at wikipedia.org.)
Apoeccrine glands are larger than eccrine glands, but smaller than apocrine ones; their secretory portion has a narrow portion similar to the secretory coils in eccrine glands as well as a wide section reminiscent of apocrine glands. Apoeccrine glands, found in the axilla and perianal region, have ducts opening onto the skin surface. They are presumed to have developed in puberty from the eccrine glands, and can comprise up to 50% of all axillary glands. Apoeccrine glands secrete more sweat than both eccrine and apocrine glands, thus playing a large role in axillary sweating.
Sweat glands are found, at least in part, to be located within fat islands assimilated in the dermal layer, as well as in the dermis-hypodermis boundary and in the upper layer of hypodermis. Thus, a substantial portion of the sweat glands is surrounded by a fat layer.
Hyperhidrosis
There are several methods by which heavy sweating (Hyperhidrosis) may be treated. The easiest and probably most commonly used way is to apply an antiperspirant (many of which contain aluminum salts) to the skin tissue surface, which forms a “plug” that blocks excretions in the form of perspiration. Many people use such antiperspirant on a daily basis.
In cases where antiperspirants do not solve an excess sweating problem, there are several medical treatments that may remedy such excessive sweating:
Iontophoresis: During this treatment, a low electrical current travels through shallow water in which the patient immerses his hands or feet (or both). Each treatment takes about 20 to 30 minutes and the patient has to repeat it at least a few times a week. No one knows exactly how this treatment works, but experts believe it blocks sweat from getting to the skin surface.
Botulinum toxin: Another treatment option for heavy sweating is injections of botulinum toxin A (Botox). It is a natural, purified protein which, when small doses are injected into the skin, blocks the nerves that supply the eccrine glands; this prevents the glands from producing sweat. By blocking, or interrupting, this chemical messenger, botulinum toxin “turns off” sweating at the area where it has been injected. Botox injections are very shallow, meaning that the materials are injected just below the surface of the skin, where they remain. Botox is FDA-approved for treating excessive sweating of the underarms, and it has been shown to result in an 82-87% decrease in sweating. Some doctors may also use Botox on the palms of the hands and soles of the feet, where it presents 80%-90% efficacy. The treatment is not a cure for hyperhidrosis—it only provides temporary relief. It needs to be repeated every three to six months for maximum effect.
Anticholinergic drugs: There are oral anticholinergic drugs that stop the activation of the sweat glands. Due to the severe side effects such as blurred vision, heart palpitations, and urinary problems, they are usually not recommended.
Surgery: This may be the only option for those severe hyperhidrosis cases that have not responded to other treatments. During surgery, the doctor may cut, scrape, or suction out the sweat glands. One surgical option is endoscopic thoracic sympathectomy (ETS), in which the surgeon makes very small incisions and cuts the nerves in the armpit that normally activate the sweat glands. This procedure is very effective, but it's used only as a last resort on people who have tried every other treatment. ETS can't be reversed, and it can leave scars. One side effect almost everyone who receives an ETS treatment has to deal with is compensatory sweating. When the body stops sweating in one area, it may start sweating in another (such as the face or chest) to compensate.
Laser systems for minimally invasive solutions for hyperhidrosis are offered by several vendors such as the companies Fotona (XP2), Deka (Smartlipo) and Cynosure (SideLaze). The systems sold by these companies use laser light to permanently destroy axillary sweat glands by photo-thermally heating sweat gland tissue with minimal damage to the surrounding tissue. In some cases the laser is introduced into the subcutaneous tissue by an optical fiber. In these cases, a local anesthetic may be infused into the area to be treated, such as the armpits, before treatment. The same vendors claim to use a specific wavelength which is claimed to be selectively absorbed by the subcutaneous tissue of the armpit. The foregoing are offered by Fontona and Deka, which provide devices operating at 1064 nm, and Cynosure, which provides a device operating at 1440 nm. A company named Miramar Labs uses a non-invasive handheld device (miraDry) to deliver precisely controlled microwave energy beneath the underarm skin to the specific area in which sweat glands are located, resulting in thermolysis (decomposition by heat) of the sweat glands. During this treatment, the top layers of the skin are simultaneously cooled and protected. Sweat glands are not believed to grow back after treatment so the effect can be seen almost immediately and results may be lasting. Some patients may only need one treatment but, for best results, two procedures spaced three months apart may be recommended.
It is to the reduction of sweating by disrupting the excretions of sweat glands that this invention is directed.
In an aspect, a cosmetic method of treating a human body to reduce hyperhidrosis includes applying laser light energy to one or more portions of the human body in which the laser light energy is approximately one or more of: about 930 nm, about 970 nm and about 1060 nm. The laser light energy may be delivered as one of: continuous or pulsed.
In another aspect, the pulse rate may be either 1 Hz or may be selected from between ½ Hz and 3 Hz. The pulses applied may be short pulses, such as is described in U.S. application Ser. No. 15/221,623, filed Jul. 28, 2016 and entitled “Apparatus and Cosmetic Method for Using Short Pulses for Dermatological Treatments”, the entire disclosure of which is hereby incorporated by reference.
In a further aspect, the methods may include the step of cooling the human body near the application of the laser light energy.
In another aspect, the time delay between pulses may be between the TRT of fat cells and the TRT of sweat glands. Thus, in
In yet another aspect, the cosmetic method may further include the step of providing bulk heating of the skin surface of the human body. Bulk heating may be delivered as the main treatment modality, as will be described below and may also be delivered in conjunction with selective targeting treatment. When bulk heating is delivered in conjunction with selective targeting treatment it may be done in one or more of: before, during and after the application of selective targeting treatment. The bulk heating may be provided by one or more of: laser light energy, IPL light energy, RF energy, microwave energy or ultrasonic energy. The bulk heating may be applied at about 400 nm to about 650 nm.
In yet a further aspect, the cosmetic method may further include providing a handpiece to deliver the laser light energy; the handpiece may include an open tip and a source of vacuum, and may include the step of drawing the skin tissue into the open tip prior to applying the laser light energy, such that the sweat glands may be drawn closer to the laser light source. Such a handpiece, such as that handpiece illustrated in
In yet another aspect, an apparatus for treating a human body to reduce hyperhidrosis may include a source of laser light energy; a controller for controlling the laser light source; the controller can cause the laser light source to apply laser light energy at approximately one or more of: about 930 nm, about 970 nm and about 1060 nm to a target tissue and disrupt sweat glands in the human body. It is to be understood that the use of the term “about” in the present application means a variance of +/−10, such that, for example, “about 930 nm” means “920 nm to 940 nm”, etc. Further, the controller may control the laser light energy to be delivered to be one of: continuous or pulsed. The controller can also control a cooling system and/or a vacuum system so that a target skin area may be drawn into the handpiece prior the application of the light energy and cooled before, during or after the application of the light energy.
In the method above and the apparatus above, the application of laser light energy may have one or more of the following parameters: (a) fluence of 5-50 j/cm2; (b) pulse width of 10-60 ms; (c) number of pulses of 1-20; (d) repetition rate of 0.3-5 Hz; (e) laser wavelength of about 970 nm.
In the present invention, a non-invasive treatment of hyperhidrosis is accomplished by means of an external laser source. The objective is to cause selective thermally induced necrosis and/or apoptosis of sweat gland while maintain the surrounding tissue intact. As mentioned above, there are several methods to obtain that objective. The key element to proper selective treatment is the relative absorption of electromagnetic radiation by the various tissue components.
Tissue bulk heating may be achieved by using a pulsed or a continuous wave laser. In this treatment mode, the entire bulk of the tissue will be heated homogenously to approximately the same temperature while treatment selectivity may be achieved due to the differences in the Damaging Temperature Threshold (DTT) which characterizes sweat glands versus the surrounding fat. Since the sweat glands' DTT is lower than that of fat, selectivity may be achieved by increasing the bulk temperature to a level which is higher than the DTT for sweat glands but lower than the DTT of fat.
By using the radiation wavelengths in region 301, the sweat glands which are surrounded by fat tissue by heating the surrounding fat layer are targeted. Thus, the fat tissue can be targeted and its temperature increased to a certain level that initiates necrotic and/or apoptotic processes in the sweat glands embedded in it, while leaving the dermis tissue at a lower temperature.
Irradiating the tissue with wavelengths in the region 301 of
A waveband which favors absorption by fat compared to water, such as 400 nm-650 nm, may be used. In this case, low power continuous wave (CW) or continuously oscillating (or pulsed) radiation having relatively small peak power and substantially high repetition rate may be applied to the treated region. Gliding a laser beam producing head back and forth over a wide region in order to gradually and homogenously increase the targeted area temperature and maintain it certain level is commonly known and may be applied to treat the sweat glands as well. As before, applying cooling to the epidermal layer reduces the risk of adverse effects.
In contrast, in region 302, the sweat glands are targeted directly to increase their temperature to sufficient levels and for a sufficient duration. Since, in this part of the spectrum, the absorption of light in water is higher than is fat, the sweat glands' temperature will increase faster than in the surrounding fat layer. This enables a selective treatment which is based on non-homogenous heating of the target tissue and direct targeting of the sweat glands. In addition, the fatty layer which surrounds the water based sweat gland thermally isolates it from the environment and effectively increases its thermal relaxation time (TRT). Thermal relaxation time is the duration required for the heat generated by absorbed light energy within the targeted chromophore to dissipate to 50% of its value immediately after laser exposure. A longer TRT enhances the selectivity of the treatment as the sweat gland will maintain its elevated temperature for a longer time, increasing the probability of initiation of apoptotic and/or necrotic processes.
Based on the facts outlined above, when selecting the specific wavelength within region 302 with which to treat, the desire may be to use a wavelength that maximizes the absorption difference between fat and water. On the other hand, the desire is for the absorption in water not to be too high. This could result in high absorption of the radiation by the epidermis and upper dermis layers (small penetration depth), with very little energy penetrating to the deeper levels of the dermis, and not be enough to affect the sweat glands.
It appears that the optimal wavelength for such a treatment may be in the 930 nm-1030 nm band, preferably at approximately 970 nm. Therefore, according to an embodiment, one suggested procedure for treating the sweat glands is with a diode laser at approximately 970 nm, based on the above analysis. The absorption at these wavelengths of energy in water is preferential compared to their absorption in fat. This is illustrated in
Thus, using approximately 970 nm may be seen as selectively targeting the sweat glands themselves over the surrounding tissue. However, as will be discussed below, differential absorption is not a panacea in and of itself, such that even lesser differentials may be useful in damaging sweat glands due to the morphological structure of water from the secretory cells embedded in fat layer, from, for example, bulk heating.
Another optional waveband in region 302 is 1030 nm-1200 nm, although it may be expected to have lower efficacy than 970 nm. However, turning now to
The 680 nm-910 nm waveband is another band, in region 301, that may be applied to sweat gland treatments, but that range may be expected to be more effective in the bulk heating of skin tissue as discussed herein
By providing selective heating of fat and the sweat glands, necrotic processes may be induced only in the sweat gland while leaving the surrounding tissue intact. Various pulse sequences using the parameters listed in table 1 were tested with a laser having a wavelength of 970 nm and indeed resulted in very selective damage to the sweat glands.
In the drawing sequence 400 of
Table 1 above provides an exemplary set of pulse sequences characteristics which may be used to treat hyperhidrosis
In order to reduce the risk of adverse effects such as burns on the epidermis to radiation absorption by melanin, local cooling may be employed during treatment. Such cooling may be accomplished using, for example, the built-in cooling mechanism provided by the “chilled tip” technology available in some products made by Lumenis Ltd. of Israel in its LIGHTSHEER® and RESURFX® product lines. Other cooling methods can be considered as well. Pre- and post-cooling further reduce side effects such as edema or pain, may provide partial anesthesia, and may reduce temperature-rise in the melanin-rich epidermis.
Cooling may be provided continuously or intermittently and may be applied during the treatment or in a combination of during the treatment and post treatment to minimize undesired skin response such as erythema, edema, purpura, without interfering with the mechanism of heat accumulation in the sweat glands. Topical cooling of skin surface during or after energy delivery to the tissue may avoid heat accumulation even in upper layer of dermis, contributing to the procedure safety and allowing more energy to be transmitted to the tissue as and if needed.
Further enhancement of treatment efficacy might be obtained when delivering the treatment by applying vacuum to the treated area. The handpiece illustrated in
While the foregoing has discussed wavelengths in the regions 301 for bulk heating and in region 302 for more targeted heating, the wavelengths do not need to be restricted to either one of the wavelengths or spectrums mentioned above, but may also be a combination of a “mix and match” of two or more of the above wavelengths or spectrums, from the same region 301 or 302 or from both regions, according to the planned treatment of affecting the sweat glands and/or the fatty components. Also, a combination of bulk heating and, as appropriate, pulsed treatments may be combined to achieve the desired effects of damaging the sweat glands. A programmed controller may be employed to control and sequence these different treatment parameters.
While the foregoing general discussion has been directed to treatment of axillar sweat glands, it is to be understood that other body parts may be treated with the present inventions, such as the soles, palms, forehead, back, chest, and groin, as well as in the treatment of bromhidrosis (foot odor) and osmidrosis (heavy sweat odor) in various parts of the human body.
Typically, for a chilled tip hand piece configuration, the hand piece will be positioned using a “pick and place” or “gliding” or “painting”, depending on the wave form used, while maintaining firm compression during the entire treatment.
In the “pick and place” method, the tip is picked up from the skin immediately after the pulse, moved to the next treatment location, and then lowered against the skin. In the “gliding” technique, the tip is kept continuously in contact with the skin and moved to the next treatment location immediately after the laser pulse, making sure that the sapphire tip is pressed to—or in close contact with—the skin when the laser light is applied. In the “painting” technique, the operator may move the handpiece back and forth over the skin surface.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IL2017/050174 | 2/12/2017 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62295032 | Feb 2016 | US |
