Patent Application
20120330288
The present invention relates to a device and a method for treating the epidermis. More in particular, the present invention relates to a device and a method for treating the epidermis by means of an equipment comprising a laser beam of adequate wave length, so as to obtain given effects on the epidermis, such as for example the reduction of wrinkles and an overall effect of rejuvenation.
Medical and aesthetic treatments are increasingly spread for improving the physical appearance, for solving problems connected to skin blemishes and also for treating and solving situations of real psychological trouble resulting from the incapacity of the subject to accept his/her appearance.
Many of the various known processes, methods, and equipment, are used for treatments aiming at reducing the aging effects and therefore in particular at eliminating or reducing the formation of wrinkles on the face and on other parts of the body, such as for example the neck and the upper part of the thorax. Recently, techniques have been developed for treating the epidermis by means of laser. In many applications, a laser beam is guided in an almost uniform manner on the portion of epidermis to be treated and performs a surface ablation process, thus eliminating the upper layers of the epidermis.
The use of the laser for treating the epidermis, in particular of the face, for reducing wrinkles and other skin blemishes, is described for example in the following works: Chernoff G, Slatkine M, Zak E, Mead D., “SilkTouch: a new technology for skin resurfacing in aesthetic surgery”, in J Clin Laser Med Surg. 1995 April; 13(2):97-100; Waldorf H A, Kauvar A N, Geronemus R G; “Skin resurfacing of fine to deep rhytides using a char-free carbon dioxide laser in 47 patients.”, in Dermatol Surg. 1995 November; 21(11):940-6; David L M, Same A J, Unger W P., “Rapid laser scanning for facial resurfacing.”, in Dermatol Surg. 1995 December; 21(12):1031-3; Lask G, Keller G, Lowe N, Gormley D., “Laser skin resurfacing with the SilkTouch flashscanner for facial rhytides.”, in Dermatol Surg. 1995 December; 21(12):1021-4; Apfelberg D B., “Ultrapulse carbon dioxide laser with CPG scanner for full-face resurfacing for rhytids, photoaging, and acne scars”, in Plast Reconstr Surg. 1997 June; 99(7):1817-25; Apfelberg D B, Smoller B.“UltraPulse carbon dioxide laser with CPG scanner for deepithelialization: clinical and histologic study”, in Plast Reconstr Surg. 1997 June; 99(7):2089-94; Raulin C, Drommer R B, Schonermark M P, Werner S., “Facial wrinkles—ultrapulsed CO2 laser: alternative or supplement to surgical face lift?”, in Laryngorninootologie. 1997 June; 76(6):351-7; Trelles M A, Rigau J, Mellor T K, Garda L., “A clinical and histological comparison of flashscanning versus pulsed technology in carbon dioxide laser facial skin resurfacing”, in Dermatol Surg. 1998 January; 24(1):43-9; Weinstein C., “Computerized scanning erbium:YAG laser for skin resurfacing”, in Dermatol Surg. 1998 January; 24(1):83-9; Bernstein L J, Kauvar A N, Grossman M C, Geronemus R G., “Scar resurfacing with high-energy, short-pulsed and flashscanning carbon dioxide lasers”, in Dermatol Surg. 1998 January; 24(1):101-7; Vaïsse V, Clerici T, Fusade T., “Bowen disease treated with scanned pulsed high energy CO2 laser. Follow-up of 6 cases”, in Ann. Dermatol. Venereol. 2001 November; 128(11): 1220-4.
Recently methods have been developed, wherein the treatment of the epidermis is discontinuous, i.e. on a given region to be treated the laser is focused in discrete areas separated from each other by areas not irradiated with the laser beam. The regions irradiated by the laser beam are subjected to an ablation in substantially cylindrical volumes, spaced from each other by wide volumes, on which no treatment is performed. Methods of this type are described in Toshio Ohshiro et al, “Laser Dermatology—State of the Art”, proceedings of the 7th Congress
International Society for Laser Surgery and Medicine in Connection with Laser 87 Optoelectronics, ed. Springer—Verlag, 1988, pages 513 ff. The same methods are described in U.S. Pat. No. 6,997,923.
In this way an attempt is made to conjugate the need for ablating the tissue, which involves a localized damage of the tissue and an erythema due to the high heating caused by the laser, with the need for a process that is as less invasive as possible. It has been thought that, by acting in limited portions of tissue, spaced from each other by wide areas absolutely not exposed to the laser beam, treatment effects (for example of reducing or eliminating wrinkles) could be achieved, similar to that obtained through a full volume or full surface treatment of the classic type, but with a lower side effect of damage on the epidermis, a lower formation of erythemas and in general a reduction of the recovery times necessary after the treatment.
Processes of this type are described for example in the following works: Fitzpatrick R E, Rostan E F, Marchell N., “Collagen tightening induced by carbon dioxide laser versus erbium: YAG laser”, in Lasers Surg. Med. 2000; 27(5):395-403; Hasegawa T, Matsukura T, Mizuno Y, Suga Y, Ogawa H, Ikeda S., “Clinical trial of a laser device called fractional photothermolysis system for acne scars”, in Dermatol. 2006 September; 33(9):623-7; Rahman Z, Alam M, Dover J S., “Fractional Laser treatment for pigmentation and texture improvement”, in Skin Therapy Lett. 2006 November; 11(9):7-11; Laubach H, Chan H H, Rius F, Anderson R R, Manstein D., “Effects of skin temperature on lesion size in fractional photothermolysis”, in Lasers Surg Med. 2007 January; 39(1):14-8; Collawn S S., “Fraxel skin resurfacing”, in Ann Plast Surg. 2007 March; 58(3):237-40; Hantash B M, Bedi V P, Chan K F, Zachary C B., “Ex vivo histological characterization of a novel ablative fractional resurfacing device”, in Lasers Surg Med. 2007 February; 39(2):87-95; Hantash B M, Bedi V P, Kapadia B, Rahman Z, Jiang K, Tanner H, Chan K F., “In vivo histological evaluation of a novel ablative fractional resurfacing device”, in Lasers Surg Med. 2007 February; 39(2):96-107.
The effectiveness of these methods is doubtful. In particular, acting on too close volumes does not allow obtaining significant improvements in terms of reduction of the recovery times, whilst treating volumes too spaced out through untreated areas involves the risk of an insufficient result and therefore the need for a second intervention.
To limit or overcome entirely or partially one or more of the drawbacks of the known techniques, the present invention provides for a device and a method, wherein the treatment is less invasive, as it does not provide for treated and untreated areas, but it provides for modulating in an adequate manner the energy density of the laser beam on the surface of the epidermis. In particular, according to one aspect of the present invention, it is provided for irradiating a portion of epidermis, to be treated with a series of laser beams, or with at least one scanned beam, which has a particular profile of energy density, and more precisely with a greater density in the center (i.e. near the axis of the beam) and a lower energy density towards the periphery of the beam. Preferably, according to some embodiments, the energy density has, in the direction of the radius of the section of the beam, a profile similar to a Gaussian curve.
In this way it is possible to treat all the region of epidermis of interest, without leaving regions not invested by the laser beam. However, the modulation of the beam, i.e. the variation of the energy density along the radius, from the axis to the most external region of the beam, allows obtaining a differentiated effect in each portion invested by the beam. In the central area (A) of the skin surface, invested by the laser beam, the energy density is sufficient to cause the ablation of the tissue. This causes a fissile ablation in a substantially cylindrical volume below the skin surface invested by said central area of the laser. In an annular surface surrounding the central area (A), the laser beam has a substantially lower energy density, and causes, in the volume below this annular surface (volume (B) presenting a hollow conformation) a cauterization effect, i.e. an effect of hemostasis of the blood vessels and/or an effect of shrinkage of the collagen, but not an effect of laser ablation. In some preferred embodiments of the present invention, outside of this area (B), below the annular surface, there is another area (C), in the shape of a hollow volume, bordering the other areas (C) due to the actions of the laser in adjacent pointings, in which the laser beam has an intensity even lower than in the inner area (B); in this area (C) there is a biostimulation by means of the laser light that facilitates the tissue regeneration of the collagen.
In this way, given a region of epidermis to be treated, the volume underneath the entire region is exposed to the laser beam, without leaving tissue volumes not hit by the energy irradiated by the laser. In this way a greater effectiveness of the treatment is achieved. However, as the ablation effect is limited to the most internal volume, the tissue damage, the erythema and the subsequent discomforts for the patient are substantially reduced, with a consequently shorter recovery time.
Furthermore, the cauterization of the tissues in the volumes (B) exposed to the portions of beam of lower intensity, relative to the axial portion of the beam, reduces the bleeding effects. In this outer volume the intensity of the laser beam, i.e. the energy density of the beam, is sufficient to cause a shrinking effect of the collagen and therefore, even if no ablation of the tissue occurs in this area, there is a substantial contribution of the laser energy to the final result of the intervention. Shrinking of the collagen, which represents an important component of the tissue, in the areas (B) and partially in the areas (C), gives to the tissue a more compact aspect immediately after the treatment, eliminating or reducing skin slackening due to aging. Furthermore, the remaining tissue in the areas (C) is subjected to the laser biostimulation action that, in the medium and long term, facilitates acceleration of the collagen regeneration; this represents a typical aspect of the treatment introduced with the technique in question.
Contrary to the most recent techniques of fractional laser treatment, wherein the laser treats discrete areas or volumes of tissue, leaving wide areas or volumes not irradiated, the present invention therefore provides for investing all the tissue with the laser, but causing on it and inside it different phenomena by modulating, or shaping in an adequate manner the profile of energy density of the beam section.
Given a portion of epidermis to be treated, this can be irradiated simultaneously by more beams, obtained for example by a single beam through particular optical systems. The various beams are for example arranged according to an adequate pattern, e.g. a matrix pattern. However, it is possible preferably to use a single beam or more than one beam, to which a scanning movement is imparted according to coordinates (for example Cartesian or polar coordinates). In some embodiments of the present invention the emission of the beam is controlled in such a manner that single beams of laser energy are “shot” in sequence in sequentially variable positions along a preset pattern, for example according to nodes of a matrix. In other embodiments it is possible to move the laser beam from a position to the other without interrupting the emission of energy, providing a sufficiently short time to pass from a treatment position to the other. In this way, the effect of the laser during the movement from an irradiation point to the other is substantially negligible relative to the effect of the beam during the phase of stopping in a given point or position of the irradiation pattern.
In any case, it is possible to provide that adjacent beams (irradiated simultaneously or sequentially through a scanning system) have superposition areas, i.e. areas in which the effect of two adjacent beams (or of three or more adjacent beams) are superposed and summed. Obviously, also depending upon the scanning operation or multiple beam operation and, in the first case, upon the scanning time, only the spatial or also the temporal superposition of the beams shall be taken into account.
In the areas of superposition, in fact, the effects of more beams which can fall on the tissue in temporal sequence, due to the scanning of the beam will be summed. In this case it should be taken into account that in a given volume surrounding the ablation area the effects of more laser beams applied in different times are summed and therefore these effects are influenced by the fact that the heat generated by a first application of the beam in a position is at least partially dispersed due to the effect of the blood circulation (and/or of the thermal convection on the surface of the epidermis) before the effect of the second beam arrives.
According to advantageous embodiments of the present invention, the energy density profile of the laser beam can be such as to define, in addition to the central volume wherein the ablation of the tissue occurs and the surrounding volume wherein the cauterization and/or shrinking of the collagen occurs, a third volume wherein the energy of the laser beam is even lower and such as not to cause substantial effects of collagen shrinking and/or of cauterization or hemostasis of the vessels, but a biostimulation effect. In fact, it is known that, by irradiating a living tissue with a laser beam, it is possible to stimulate the cell differentiation and multiplication. In this way it is possible to shorten the recovery times of the patient after the intervention, as the tissue removed by ablation is replaced more quickly by new tissue. The effect of a superposition of more beams can occur in the area of intermediate energy density, wherein the laser energy is sufficient to cause the cauterization of the vessels and/or the collagen shrinking; alternatively, or in combination, this superposition of the beams can occur only in (or also in) the most external area, wherein the laser energy is only sufficient to obtain the biostimulation of the tissue.
Therefore, the object of the present invention is a device for the laser treatment of the epidermis, comprising: a source of laser energy; a focusing system for focusing the laser energy, arranged and controlled to focus the laser energy on a plurality of adjacent volumes of an area of the epidermis; wherein said laser energy is applied to each of said volumes with a laser beam having a profile of energy density variable in a cross section of said beam, in a central area of said cross section the intensity of the beam being suitable to cause an ablation of the epidermis in a central portion of the volume hit by the laser beam, and in an external annular area of said cross section the intensity of the beam being suitable to cause hemostasis, i.e. cauterization of the blood vessels and shrinking of the collagen of the epidermis in an annular portion of the volume exposed to the laser beam, said annular portion surrounding said central portion. The adjacent volumes can be also partially superposed.
In some embodiments of the present invention, the focusing system for the laser energy is arranged and controlled so as to treat adjacent volumes of the epidermis arranged according to a pattern, in which each treated volume has a center substantially positioned on the axis of the laser beam used for treating said volume, the axes of the laser beams used to treat said adjacent volumes being arranged according to a dot matrix that can be preset.
Focusing system include both a dynamic system, comprising a scanning device, to move the beam in different positions, and a system of static type, wherein an adequate optical system subdivides for example an initial beam into a plurality of adjacent beams arranged according to an adequate pattern, for example according to a matrix.
In some embodiments of the present invention, the energy density profile of the laser beam to treat said adjacent volumes and the distance between the dots of said presettable matrix are such that the full treated area of the epidermis is subjected to the action of the laser energy, in particular in the volume outside of the annular area of the section of the laser beam, wherein the intensity of the beam is suitable to cause the hemostasis of the blood vessels, the laser energy being suitable to cause a biostimulation of the tissues.
A further object of the present invention is a device for treating with a laser radiation the epidermis of a patient, comprising: a laser source; a scanning and actuating system to address a laser beam on a plurality of portions of an area of epidermis to be treated, controlled so as to actuate a laser beam in a plurality of positions inside said area of epidermis to be treated; wherein the laser beam has an energy density profile variable from the center towards the periphery of the cross section of said beam, in a first central area of said cross section the intensity of the beam being suitable to cause an ablation of the epidermis exposed to said beam, and in a second external annular area of said cross section the intensity of the beam being suitable to cause hemostasis of the blood vessels and/or a shrinking of the collagen of the epidermis in an annular portion of the epidermis exposed to said beam.
According to a further aspect, an object of the present invention is a device for treating with a laser radiation the epidermis of a patient, comprising: a laser source; a focusing system for focusing the laser energy, arranged and controlled so as to focus the laser energy on a plurality of volumes of an area of the epidermis to be treated, wherein said laser energy is applied through beams with variable energy density, which is greater in the central area and lower in the peripheral area of the cross section of the beam; the energy density of the laser beam in the central area being such as to cause an ablation in a plurality of first portions of epidermis spaced from each other in said area, surrounded by second portions of epidermis in which the laser energy causes the cauterization or hemostasis of the blood vessels and/or the shrinking of the collagen of the epidermis, outside of said second portions being defined third portions wherein the laser beam causes a biostimulation of the tissues.
According to a further aspect, the invention relates to a method for treating the epidermis of a patient, comprising: the application of laser energy in a plurality of portions of epidermis in an area of the epidermis to be treated with a distribution of energy in each portion which causes an ablation of the epidermis in the central area of said portion of epidermis and an hemostasis of the blood vessels and/or the collagen shrinking in an annular area of said portion of epidermis, surrounding said central area and outside it.
Preferably, the method also comprises the phase of biostimulating, through the laser energy, the tissue surrounding the annular area in each portion of treated epidermis.
Preferably, all the volume of epidermis in said area is treated with said laser energy. The volume of treated tissue extends from the external skin surface for a given depth inside the epidermis, according to the characteristics of the tissue and the characteristics of the laser beam. Said penetration depth will be in general different in the various areas according to the power density of the laser, for example the penetration will be deeper in the area with the greater energy density. It is understood that all the volume of the epidermis is treated when there is at least one minimum depth of penetration, such that all the volume between the external surface and this minimum penetration depth is exposed to the laser radiation. There is therefore a layer (which can have variable thickness) of tissue achieved by the laser radiation in a continuous manner, i.e. without volumes not exposed to the laser radiation.
According to a preferred embodiment of the present invention, the areas of epidermis to be treated are sequentially exposed to a laser beam controlled by a scanning system.
According to a further aspect, an object of the present invention is a method for treating the epidermis of a patient, comprising: treating with laser energy adjacent volumes of an area of epidermis, in each volume the laser energy being applied with an energy density greater in a central portion, to cause the ablation of the tissues in said central portion, with an intermediate energy density in an intermediate portion, surrounding said central portion, to cause the collagen shrinking and/or the hemostasis or cauterization of the blood vessels in said intermediate portion, and with a lower energy density in an external portion, to cause the biostimulation of the tissues in said external portion.
According to a further aspect, the present invention relates to a device and a method for treating tissues, wherein a radio frequency emission is combined with a laser radiation, i.e. to a system comprising one or more electrodes generating a radio frequency electric field, the electrodes being designed so as to propagate the radio frequency electric field in the tissues and in particular in the epidermis under treatment. These two emissions (laser and RF) can be applied in time sequence, alternatively firstly the laser and then the RF or vice versa, or they can integrally or partially overlap each other. Preferably, a handpiece is provided with a spacer formed by one or more elements constituting at the same time electrodes for applying and propagating the radio frequency field inside the treated tissue.
Radio frequency in aesthetic treatments is known per se, see for example Goldberg D J, Fazeli A, Berlin A L. “Clinical, laboratory, and MR1 analysis of cellulite treatment with a unipolar radiofrequency device”, in Dermatol Surg. 2008 February; 34(2):204-9; or Montesi G, Calvi eri S, Balzani A, Gold M H., “Bipolar radiofrequency in the treatment of dermatologic imperfections: clinicopathological and immunohistochemical aspects”, in J. Drugs Dermatol. 2007 February; 6(2):212-5. Combined applications laser and RF, or handpieces combined for a synergic action of the two types of energy are not known. The combination of laser radiation and radio frequency allows significant advantages to be obtained. In particular, such a combination allows obtaining the following synergic effect: in the central part of the treated region, the laser causes a tissue ablation and therefore the formation of small holes in the epidermis. These allow the lines of radio frequency electric field to close faster in the skin and therefore they allow obtaining a more effective heating of the collagen by the radio frequency field with a consequent increase in the collagen shrinking effect. The effect of the radio frequency electric field is therefore more effective than that which can be obtained only with the radio frequency field. Some of the advantages which can be obtained from this combination of laser radiation and radio frequency field can be obtained also with a power distribution of the laser beam which is traditional in shape rather than Gaussian.
The invention will be better understood by following the description below and the attached drawing, which shows a non-limiting practical embodiment of the present invention. More in particular:
In some embodiments of the present invention, the most relevant parameters of the equipment can fall within the following ranges of values:
The laser can be controlled so as to provide a pulse for each position of the scanning mirrors, i.e. for each treated point. However, in other embodiments of the present invention it can be provided for “shooting” more than one laser pulse for each working position, i.e. at each treated point. For example, from two to five pulses can be provided for each position of the laser.
To obtain the Gaussian shape of the beam, the laser cavity is designed so as to insulate the main propagation mode and the focusing optical systems must be designed so as to contribute to maintaining the Gaussian shape of the energy distribution from the axis towards the outside. An adequate choice of the diameter of the cavity and an adequate radius of the mirrors of the laser source can give the generation of the oscillation mode TEM 00 that gives a Gaussian beam profile.
The laser beam can be conveyed through a wave guide 7 towards a handpiece 9. The guide can be designed in different manners, also depending upon the frequency and the emission power of the laser. In the illustrated example the wave guide is simply formed by hollow tubular elements, hinged to each other, inside which deflection mirrors for the laser beam are arranged, to deviate the beam along the axis of the various tubular portions of the guide.
Inside the handpiece 9 focusing and/or scanning systems for the laser beam are arranged, some of which are schematically represented in
Through the handpiece 13 and the scanning system inside it, it is possible to control the movement of the beam F according to a defined and stored pattern, which can be modified by the user if required.
A focusing optical system is arranged in an adequate point of the path of the laser beam. In the diagram of
In other embodiments of the present invention, inside the handpiece 15 focusing systems are arranged that subdivide the laser beam into a plurality of beams that are adjacent to each other and impart an energy density profile to each of the adjacent beams, depending upon the radius according to the criteria described hereunder.
The lens inside the handpiece, combined with the shape of the beam generated by the source, causes the Gaussian profile; the generated shape of the beam depends upon the purity of the propagation mode inside the laser cavity, which determines therefore the energy distribution transversally to the axis of propagation in the free space at the exit of the laser source.
In some preferred embodiments of the present invention, the laser beam or each laser beam has a substantially circular cross section. Characteristically, the laser beam or each laser beam as a profile of energy density variable according to the distance from the axis. In other words, the energy density of the beam varies from the centre of the beam, where there is the greater density, towards the periphery of the beams, where there is the lower energy density.
On the axis of ordinates four energy density values have been identified, indicated respectively with E1, E2, E3, and E4. The values E1, E2, E3 and E4 can vary in a highly significant manner, as in their determination many parameters intervene, resulting from the interaction between laser radiation and biological tissues. These parameters depend upon the type of skin (dry or oil skin; phototype, etc.) by the angle of incidence, and by the adjustments made by the doctor based upon the experience for the various cases.
The energy density levels comprised between E1 and E2 are such that the tissue irradiated with an energy density comprised between these two levels is affected by an ablation process, i.e. a process of removal of the tissue. The energy density greater than the energy level E2 is achieved only in points contained inside the cylindrical volume of the laser beam with radius R2.
The energy density comprised between the values E2 and E3 is not sufficient to cause tissue ablation, i.e. the removal of the irradiated tissues. However, for these intermediate values of energy density cauterization phenomena occurs in the irradiated tissues, i.e. phenomena of hemostasis of the blood vessels. This avoids bleeding in the regions where the ablation occurred. Furthermore, or alternatively, the energy density levels E2 and E3 define an interval within which the laser beam causes a shrinking of the collagen contained inside the irradiated volume of tissue. Therefore in the volume irradiated with an energy density comprised between E2 and E3 a beneficial effect occurs on the collagen fibers, which causes a toning up of the tissue of the epidermis and therefore a positive result in terms of decrease of the aging effects. As in the volume irradiated with energy density comprised between E2 and E3 the ablation does not occur, the tissue damage results to be particularly limited. In
The most external annular region of the cross section of the beam comprised between an inner radius R3 and an outer radius R4 is characterized by an energy density comprised between the level E3 and the level E4. In this interval, the laser energy is no longer sufficient to cause significant shrinking of the collagen fibers and/or cauterization or hemostasis of the blood vessels, but it is still sufficient to cause significant effects of tissue biostimulation. Consequently, in the affected area there is an effect of the laser that contributes to the post-intervention recovery, stimulating the growth of the tissues subjected to ablation in the most internal region of the portion of epidermis exposed to the single laser beam. In some embodiments of the present invention the radii R2 and R3 can assume the following values: R2: from 60 to 175 micrometers according to the set parameters
R3=R2+50 micrometers
According to the present invention, it is advantageously provided to invest a preset area of the skin with a plurality of laser beams, each of which has an energy density shape represented qualitatively by the curve of
The beams, with which the portion of epidermis to be treated is irradiated, can be constituted by beams arranged side by side and generated with an optical system of the type represented in
Independently of the system of generation of adjacent laser beams, it is possible to irradiate the epidermis for example by following a pattern as represented in
The difference between the pattern of figure A and the pattern of
It should be understood that the greater or smaller overlapping can affect the dimension of the regions subjected to shrinking of the collagen fibers/hemostasis of the vessels and/or biostimulation, depending also upon the trend of the curves representing the power density. Substantially, it is possible to model the regions subjected to the three above mentioned effects by adequately shaping the energy density profile and/or dimensioning in an adequate manner the irradiation pattern, i.e. the positions in which the single beams are arranged, with which a portion of epidermis is simultaneously irradiated, or the positions taken sequentially by a single laser with a scanning system.
In some embodiments of the present invention it is also possible to shape the energy density curves and/or to arrange the axes of the beams, with which the portion of epidermis under treatment is irradiated, so as to reduce or to completely eliminate the regions in which there is the biostimulation and to obtain in the treated volume of tissue only two effects, respectively ablation and cauterization and/or shrinking of the collagen. Such a situation is schematically represented in
In the practical application of the method described above, a region of epidermis to be treated will be defined, and on this region the laser beams will be addressed. In a case (with a system of the type illustrated in
By shaping the energy density profile and the position of the beams it is possible to modify the dimensions and the positions of these three treatment areas. The beam penetrates below the surface of the epidermis and therefore to each circular surface, annular surface or intermediate surface between the annular surfaces corresponds an underlying volume in the tissue and in the epidermis. In general, the entire surface is therefore treated and all the tissue volume within a given depth, which can vary from point to point, is irradiated by the beam, living no regions devoid of treatment, but modulating the treatment, thus obtaining different effects from a region to the other. This surprisingly allows the advantage of lower invasivity of the intervention, much faster recovery times, but at the same time an effectiveness of the treatment much greater relative to that which can be obtained with beams of substantially constant energy density in all the section and spaced from each other so as to leave regions of epidermis not irradiated and therefore where the laser has no effect.
According to improved embodiments of the present invention, the laser treatment is combined with a treatment by means of radio frequency application.
Using the electrodes as spacers, a particularly compact instrument is obtained, economical and easy to use.
With such a handpiece it is possible to combine in a synergic manner the effects of the laser and of the radio frequency on the treated tissues. More in particular, the radio frequency emission allows heating the tissues below the tissues exposed to the laser radiation, so that also the underlying collagen layers are subjected to heating, induced in this case by the radio frequency, and are subjected to a shrinking, which results in toning up the skin. When the electrodes 113 rest on the skin to be treated, for instance on the face of the patient, as shown in
The laser radiation and the radio frequency can be combined or temporarily overlapped in different manners. The diagram of
Δt1 can vary for example between 10 seconds and −(t2−t1)
Δt2 can vary for example between 10 seconds and −(t2−t1) as graphically represented in
(t1−Δt1)<(t2−Δt2)
it is possible to vary the starting time and the ending time of the radio frequency emission relative to the interval of laser treatment. The variation can be continuous or discontinuous. For example, it is possible to provide for a stepped regulation with steps of 0.01 seconds or less. In this way it is possible to start the radio frequency emissions ten seconds before the laser treatment or in a subsequent time, which can be temporarily translated until at most it coincides with the end time of the laser emission, thus making the two treatments in time sequence instead of in overlapping, starting with the laser radiation and then prosecuting with the RF radiation. The ending time of the RF radiation can be from ten seconds after the end of the laser emission or it can be advanced until to coincide with the instant corresponding to that in which the laser emission starts. Also in this case the two treatments are performed in sequence, firstly the radio frequency treatment and subsequently the laser treatment.
When Δt1=Δt2=0, the two treatments (laser and RF) are temporarily overlapped and have the same time duration.
Example of values, which can be used in the combined laser+radio frequency electric field application, are the following:
In general, the space between the pulses can vary between 0.01 and 5 mm and preferably between 0.1 and 3 mm. The laser power can vary between 0.5 and 70 W, preferably between 2 and 50 W and more preferably between 10 and 40 W. The power of the radio frequency field can be comprised between 0.1 and 30 W, preferably between 1 and 20 W and more preferably between 4 and 18 W. Lastly, the energy per pulse of the laser beam can be comprised between 1 mJ and 200 mJ, preferably between 10 mJ and 100 mJ and more preferably between 20 mJ and 100 mJ. It should be understood that the data indicated above are given exclusively by way of non limiting example and that it is possible to use also data outside these intervals. Furthermore, also intermediate intervals between that indicated are comprised in the present description, being understood that the present description relates to any intermediate value and to any intermediate interval between the indicated values.
It is understood that the drawing only shows an example provided by way of a practical demonstration of the present invention, which can vary in forms and arrangements without however departing from the scope of the concept underlying the invention. Any reference numbers in the appended claims are provided to facilitate reading of the claims with reference to the description and to the drawing, and do not limit the scope of protection represented by the claims.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IT10/00037 | 2/4/2010 | WO | 00 | 9/12/2012 |
