WO1998024509A1

WO1998024509A1 - Radiofrequency device for the treatment of cellulitis and other therapies

Info

Publication number: WO1998024509A1
Application number: PCT/IB1997/001496
Authority: WO
Inventors: Francesco Garbagnati; Sandro Rossi
Original assignee: Thermo - Med 2000 Kft
Priority date: 1996-12-03
Filing date: 1997-12-01
Publication date: 1998-06-11
Also published as: ITMI962532A0; ITMI962532A1; IT1286427B1; AU4962797A

Abstract

A radiofrequency device for the treatment of cellulitis and other therapies, comprising a radiofrequency energy generator (1) electrically connected to a passive electrode (2) and to an active electrode (3), wherein the active electrode (3) is formed of a plate (6) provided with cooling means, as well as with means for controlling the temperature of the cutaneous layer having the plate (6) applied thereon.

Description

"RADIOFREQUENCY DEVICE FOR THE TREATMENT OF CELLULITIS

AND OTHER THERAPIES"

The present invention relates to a radiofrequency device for the treatment of cellulitis and other therapeutic treatments by means of local hyperthermia in the concerned tissues.

Various methods are known to be used at present in the cellulitis therapy, such as liposuction, local injection of lipidic solvents and hyperthermia with infrared rays. Infrared rays act so as to increase the temperature of the subcutaneous tissue while passing through the cutaneous layer and causing the liquefaction of the adipose tissue, which may be then put in the bloodstream by massage or lymphodrainage. However, the use of infrared rays has the drawback of causing burns to the cutis, so that at present hyperthermia is limited to temperatures close to the body temperature. This results in considerable limits to the amount of liquefied adipose tissue and in longer times of treatment. In fact, higher treatment temperatures favor a quicker liquefaction of the adipose tissue and thus its quicker redistribution in bloodstream.

The object of the present invention is to provide a means allowing the localized heating of the adipose tissue even at temperatures far higher than the body temperature without resulting in burns to the cutis. Such an object is achieved by a radiofrequency device having the features specified in claim 1.

The radiofrequency is already used in the medical field, e.g. in the tumor therapy. Tumoral tissues are necrotised by using needle-shaped electrodes inserted into the tumoral tissue itself. The radiofrequency device according to the present invention has the advantage not to comprise an active electrode to be inserted into the human body; the active electrode used in the device according to the present invention is applied externally on the cutaneous tissue.

Another advantage of the device according to the present invention is to allow an accurate real-time measure of the temperature, both in the adipose tissue and on the subcutaneous tissue.

These and other advantages of the device according to the present invention will be evident to those skilled in the art from the following detailed description of an embodiment thereof, wherein:

Figure 1 shows an axonometric diagrammatic view of the device according to the present invention;

Figure 2 shows an enlarged cross-sectional view of the device according to the present invention; and Figure 3 shows a diagrammatic view of a particular embodiment of the device according to the present invention. Referring to Figure 1 , the device according to the present invention is formed of a radiofrequency energy generator 1, electrically connected to a passive electrode 2 and to an active electrode 3 through cables 4 and 5, respectively.

Generator 1 is of a known type and thus it does not require a specific description. Also passive electrode 2 is of a known type and is intended to be applied on the patient's cutis in a diametrically opposed position with respect to the one having active electrode 3 applied thereon.

Active electrode 3 must be applied on the cutis portion to be treated. Since it is the receiver of the radiofrequency waves, its surface is smaller than electrode 2. Electrode 3 has a novel structure which is best described referring to Figure 2.

When operating generator 1, the radiofrequency energy supplied therefrom results in the desired hyperthermia in the adipose tissue, until the temperatures are reached whereat the cells of the adipose tissue are liquefied. The temperature in the cutaneous and subcutaneous zones is instead kept at normal levels by virtue of the special structure of electrode 3.

Referring to Figure 2, electrode 3 is formed of a sheet plate 6 having applied thereon suitable cooling means 7. Plate 6 is made of conductive metal sheet of the type commonly used for acusector plates. It is preferably provided with suitable means 8 for controlling the temperature of the cutaneous layer and preferably also provided with means 9 for controlling the temperature inside the adipose tissue.

Control means 8 are preferably very thin thermistors of a known type. Means 9 are preferably needle micro-thermistors to be implanted in the subcutaneous adipose area.

Also cooling means 7 may be of a known type and act so as to convey out of the patient's body the heat generated by the radiofrequency in the cutaneous and subcutaneous layers. Suitable means may be e.g. small-sized heat exchanges, or a coil having a cooling fluid flowing therethrough, or simply ice. Cooling means 7 represented in Figure 2 are formed of an ice container fastened on plate 6 by means of a lock 10.

The portion of plate 6 intended to contact the cutis is preferably covered with an adhesive and conductive paste. The opposite portion is instead cooled, thereby allowing to keep the temperature of the cutaneous zone at about 37 °C, while the intensity of the radiofrequency field may be so increased as to reach temperatures causing the liquefaction of the concerned adipose tissue.

The device according to the present invention may be used also as passive electrode of electromedical tools, as well as in the treatment by local hyperthermia of superficial or subcutaneous tumoral pathologies and osteoarticular pathologies. Plate 6 may have a simple flat surface, or may be formed of a plurality of small plates connected to main cable 5. The use of multiple plates may result in a better heat distribution, even when using large-sized plates.

Cooling means 7 which in the practice proved to be particularly satisfactory are the Peltier effect thermoelectric plates. Such plates allow to reach very low temperatures, e.g. about -30°C, otherwise unreachable by using water cooling. Low cooling temperatures allow the treatment of tissues with larger amounts of radiofrequency energy, so that deeper treatments in the tissues can be carried out, resulting in greater therapeutical benefits. The use of Peltier plates as cooling means has been especially advantageous in the hyperthermia treatment of tumoral tissues. The great amounts of radiofrequency energy allowed by such a use allow to carry out selective necrosis in the tumor as well as to wholly destroy it while keeping intact the cutaneous surface.

In a particularly preferred embodiment of the present invention, a Peltier plate is directly in contact with an active electrode 3. Such an embodiment is shown in Figure 3, wherein the active electrode 3 is in contact with a Peltier plate 11, which is electrically connected to a power source. With the exception of the lower surface to be put in direct contact with the cutis, the surface of active electrode 3 is preferably provided with a thin cover 12 of non-conductive material, such as plastic material, which prevents the hyperthermic step-effect around the outer edge of electrode 3. By virtue of insulating cover 12, the tissue close to the periphery of electrode 3 is protected against undesirable burns.

The opposite surface of plate 1 1 is the heat-out surface and it is preferably provided with a cooling system which helps in removing the heat pumped out by the upper surface of Peltier plate 11. Cooling system may be selected among the known liquid or gas systems.

The surface of plate 11 as well as of electrode 3 may be flat, concave or convex and its shape may be circular or polygonal, preferably with rounded corners.

Active electrode 3 is preferably provided with thermistors 8 which allow to evaluate in real time the temperature at the surface of the treated tissue in a digital format. Thermistors 8 are connected through an electric cable to a digital unit monitor (not shown) and are placed either in the middle of the surface of electrode 3 or in selected areas thereof according to the need. The thermistors 9 are very thin, preferably in form of needle micro-thermistors to be obliquely implanted in the tissue to be treated. The thickness of active electrode 3 is very low in order to reduce its thermal capacity and the reaction time of the system to the temperature variations as well as to improve the temperature control precision of the system.

The portion of electrode 3 which is intended to be brought in contact the cutis is covered with a layer of conductive gel. The combined control of the electric power supplied to the Peltier plate 11 and of the radiofrequency energy supplied to the active electrode 3 allows to reach during the treatment temperatures ranging from 50 to 120°C or higher in the subcutaneous or deeper layers, while at the surface the temperature is kept at 20-35°C. By using high power radiofrequency energy and high electric power, it is possible to obtain a necrosis area which in a couple of minutes may reach a depth of several centimeters, e.g. 4-6 cm. The necrosis size depends upon the size of the active electrode 3 which may range from 5 mm to about 30 cm.

Peltier plates are commercially well known and thus they do not require a specific detailed description.

Claims

1. A radiofrequency device for the treatment of cellulitis and other therapies, comprising a radiofrequency energy generator (1) electrically connected to a passive electrode (2) and to an active electrode (3), characterized in that the active electrode (3) consists of a plate (6) provided with cooling means (7).

2. A radiofrequency device for the treatment of cellulitis and other therapies, comprising a radiofrequency energy generator (1) electrically connected to a passive electrode (2) and to an active electrode (3), characterized in that the passive electrode (2)consists of a plate (6) provided with cooling means (7).

3. A device according to claim 1, characterized in that also the passive electrode (2) consists of a plate (6) provided with cooling means (7).

4. A device according to claims 1 to 3, characterized in that the plate (6) consists of a plurality of smaller plates.

5. A device according to claims 1 to 4, characterized in that the cooling means (7) consist of a Peltier plate (11).

6. A radiofrequency device for the treatment of cellulitis and other therapies, according to claims 1 to 4, characterized in that the cooling means (7) consist of a heat exchanger.

7. A radiofrequency device for the treatment of cellulitis and other therapies, according to claims 1 to 4, characterized in that the cooling means (7) consist of a coil having a cooling fluid flowing therethrough.

8. A radiofrequency device for the treatment of cellulitis and other therapies, according to claims 1 to 5, characterized in that the active electrode (3) is further provided with means (9) for controlling the temperature inside the treated tissue.

9. A radiofrequency device for the treatment of cellulitis and other therapies, according to one or more of the above claims, characterized in that the active electrode (3) is further provided with means (8) for controlling the temperature of the treated cutaneous layer.

10. A device according to one or more of the previous claims, characterized in that the means (8) for controlling the temperature of the cutaneous layer consist of thermistors.

11. A device according to one or more of the previous claims, characterized in that the means (9) for controlling the temperature of the adipose layer are needle micro-thermistors.