DEVICE FOR THE INVASIVE THERMOMETRICAL MEASUREMENT AND FOR THE INTRODUCTION OF A MEDICAMENT FOR SURFACE AND DEEP HYPERTHERMIA TREATMENTS

Abstract: The present invention relates to a device (1) for the invasive temperature measurement for surface and deep hyperthermia treatments, comprising a needle-pin element (2), a catheter (3) made up of a biocompatible material semirigid sheath, conformed about said needle-pin element (2), and coupled with the same in such a way that the needle-pin element (2) can be drawn out, at least a thermocouple (5), provided on the outer circumference of the semirigid sheath of said catheter (3), in known positions to the user, having the end realizing the reading point provided close to the sheath surface, coming into contact with the tissues, an application element (4) for the catheter provided with a hole to allow the drawing out of the needle-pin element (2).

Description: DEVICE FOR THE INVASIVE THERMOMETRICAL MEASUREMENT AND FOR THE INTRODUCTION OF A MEDICAMENT FOR SURFACE AND DEEP HYPERTHERMIA TREATMENTS The present invention relates to a device for the invasive thermometrical measurement and the introduction of a medicament for surface and deep hyperthermia treatments. More specifically, the invention relates to a device of the above kind which allows to reveal with the maximum precision the temperature reached employing the hyperthermia techniques in the zone to be treated, in order to optimize the therapeutic effect and if desired to introduce medicaments within the tissue. It is well known that hyperthermia is a therapy - active technology employed in the last ten years in the treatment of the cancer. During the application of the hyperthermia therapy, employing radio-frequency and/or microwave apparatuses which deposit electromagnetic waves within the organism producing heat in depth, it is necessary to make a measurement of the temperature within the treated zone, in order to obtain the maximum result. In order to obtain the maximum effect on the tumoral cells it is basic to reach within the tumour a temperature of 42.5° - 43° C, with a margin of mistaken of +/- 0,1 °C. Just in view of the need of such precision, it clearly follows the basic role of the measurement systems for the good results of the therapy. After many years of experimentation, although the technology to deposit heat in depth has been improved, the invasive thermometric systems presently available have not reached a technological level similar to the one of the apparatuses for the application of the hyperthermia, involving remarkable drawbacks and contraindications still existing. In fact, the thermometric systems presently available are made up of constantan copper thermocouples and/or optical fibres introduced within the tumour by the introduction of needles - cannulae width 14 - 18 mm (+/- 1.5 mm) and length 3 - 7.5 cm. The needles - cannulae are then drawn out leaving the wire bearing the thermocouple within the tissue. By this technology, for each needle - cannula an average number of one or two thermocouple and/of optical fibres are introduced. Since for each therapy they are necessary 8 - 15 temperature reading points, it is necessary to employ from 4 to 15 needles. This operation must be repeated for each hyperthermia treatment, for the complete cycle (5 - 10 treatments). Obviously it creates many inconveniences both for the patients, that must be each time pierced through by needles having remarkable sizes, and for the operators that have practical and technical problems in correctly positioning and maintaining the thermocouple in the reading point. In fact, for example, drawing out the needle, very often the position of the thermocouple changes within the tissue, with a negative effect for the temperature efficiency. Although it facilitates the keeping of the position of the thermocouple within the tumoral zone, the presence of the needle within the organism is not allowed since it causes very strong pains for the patient both in case of muscle twitch and for the overheating of the needle (70° - 80° C) subjected to radiofrequency RF. Summarising, the drawbacks of the present invasive thermometrical measurement systems can be individuated in a high needle / thermocouple number for each treatment, a needle cross-section that causes strong pains to the patients, a lack of precision of the positioning and maintenance of the thermocouple in the reading point, the impossibility of maintaining the needle within the organism due to the overheating determined by the radiofrequency, a scarce utilization practicality, a difficult possibility of use determining remarkable inconvenient for the use of the hyperthermia therapy in the medical field. During the years, temperature reading systems of the non invasive kind have been suggested employing the TAC, the magnetic resonance and the radiometry. However, the invasive reading of the temperature is until now the most precise and correct way. In view of the above, the Applicants have realized and set a device that can solve all the above mentioned problems, allowing to make an invasive measurement of the temperature, and eventually the introduction of a medicament, in an extremely precise, reliable and easy to be used way without any inconvenient for the patients. These and other results are obtained, according to the present invention, realizing needles / pins - catheters provided with incorporated thermocouples which allow to take the temperature within the same structure and having dimensions that almost completely avoid the discomforts characterizing the presently used solutions both for the patient and for the technician. It is therefore specific object of the present invention a device for the invasive temperature measurement for surface and deep hyperthermia treatments, comprising a needle - pin element, a catheter made up of a biocompatible material semirigid sheath, conformed about said needle - pin element, and coupled with the same in such a way that the needle - pin element can be drawn out, at least a thermocouple, provided on the outer circumference of the semirigid sheath of said catheter, in known positions to the user, having the end realizing the reading point provided close to the sheath surface, coming into contact with the tissues, an application element for the catheter provided with a hole to allow the drawing out of the needle - pin element. Preferably, said end realizing the reading point of said at least one thermocouple projects from said sheath of few hundredth of millimetres. According to a preferred embodiment of the device of the invention, said sheath can be provided with holes for the introduction of a medicament, each one preferably placed on the end of said at least one thermocouple, spaced from the same. Further, according to the invention, it is provided a plug element closing the posterior part of said catheter and supporting the needle when it is introduced within the same catheter, or can be drawn out from the catheter for the introduction of the medicament. Preferably, according to the invention, said needle - pin element is made up of stainless steel. Still according to the invention, said semirigid sheath of the catheter is made up of Teflon®. Further, according to the invention, said thermocouples are applied to the semirigid sheath by pressure - heat melting o by any other suitable technology. The number of thermocouple provided can vary preferably between 1 and 15. According to a preferred embodiment of the device according to the invention, said application element of the catheter to the human body is made up of a PVC cap - ring, eventually inclinable, having an adhesive surface contacting the skin, welded to said semirigid sheath. Further, said application element can be provided with a number of holes corresponding the number of thermocouples, in order to allow their exit, said thermocouples being collected in a further transparent sheath, preferably made up of Teflon®. The device according to the invention can be realized both reusable and disposable. The needle - pin element will be preferably a length between 1 and 8 cm. The solution proposed according to the present invention allows, as it is well evident, to obtain invasive thermometers having extremely reduced sizes, greatly facilitating the introduction within the tissues of the same and annulling almost completely the pains due to the use of the known needles. Further, the steel core of the needle - pin element gives stiffness to the structure and allows its introduction within the human tissues at the required depth (from 1 to 8 cm). The possibility of drawing out the needle - pin element facilitates the permanence of the semirigid Teflon sheath for hours within the human tissues, without creating discomforts to the patient. The adhesive application element ensure the positioning of the thermocouples in the reading points necessary for all the duration of the therapy and even more. Further, the different pressure - heat melt thermocouples allow the specific measurement of more than one temperature with the same thermometer for all the duration of the therapy (1 - 2 hours). The Teflon sheath guarantees the shielding of the metals of the thermocouple, impeding the incandescent effect due to the exposition to the radiofrequency and/or microwaves. The great number of reading points on the same thermometer allow to introduce a lower number of needles in the tumour, considerably reducing the discomfort for the patient and allowing to the therapist a greater optimisation of the treatment and thus a greater efficiency of the hyperthermia therapy. The present invention will be now described, for illustrative, but not limitative purposes, according to its preferred embodiments, with particular reference to the figures of the enclosed drawings, wherein: figure 1 is a lateral view of the device according to the invention; figure 2 is a lateral view of the needle - pin of the device according to the invention; figure 3 shows an embodiment of the catheter of the device according to the invention; figure 4 shows a second embodiment of the catheter of the device according to the invention; figure 5 shows the particular of the posterior plug of the device according to the invention; figure 6 shows a vertical section of the catheter of figure 3; figure 7 shows in still greater detail the catheter of figure 3; figure 8 is a transverse section view of the device according to the invention; and figure 9 is a transverse section view of the device according to the invention, with the needle - pin element in position. Preliminarily, it must be pointed out that the figures are not in scale. Observing first figure 1 , it is shown a device according to the invention for the invasive thermometrical measurement for surface and deep hyperthermia treatments according to the invention, generally indicated by the numeral 1. Said device comprises a needle 2 and a catheter 3, provided externally with respect to the needle 2, so that the tip of the needle projects from the catheter 3. At the bottom, said catheter 3 is provided with an element 4 for the application of the same to the human body, realized in such a way to maintain the catheter 3 in its position. The structure of the needle is shown in detail in figure 2. As already said, in the catheter 3 it is provided a plurality of thermocouples 5, having the end slightly projecting with respect to the same catheter. In figure 3 it is shown a solution having 5 thermocouples 5, while in figure 4 it is shown a solution providing 3 thermocouples 5. Obviously, the number and the position of the thermocouples 5 varies in function of the specific use, being it necessary to bear in mind that the importance of the solution is in the fact that it can provide a great number of thermocouples 5 employing only one catheter, provided in reading positions absolutely known to the user. In figure 5 it is particularly shown the plug 6 serving as closure of the catheter 3 - needle 2 assembly, and when the needle has been drawn out, it serves to close the lower end of the catheter 3 (see figure 4). The section view of figure 6 shows how the single thermocouples are provided within the catheter 3 and shows the wires 7 and 8 for the electric connection of the thermocouples 5 to the power supply and to the reading apparatus. These features are also well evident from figures 7, 8 and 9. Particularly, from figure 7, it can be noted the male sockets 9 of the single thermocouples 5 connected to the wires of the thermocouples coming out from the catheter. Instead, the sections of figures 8 and 9 allow to particularly appreciate the structure of the catheter 3 with the wires 7 and 8 from the thermocouples buried in the same. In figures 6 and 7 the holes 10 for the introduction of the medicament. The device according to the present invention can be used as follow. The needle 2 chosen is introduced (between 1 and 12 cm - between 1 and 15 reading points) within the tissue until to make the adhesive ring crown 4 adhering on the skin. Then the stainless steel inner core is drawn out and it is closed by the flat micro plug 6 the centre of the opened catheter. Finally, all the male socket 9 of the thermocouples 5 projecting from the ring 4 are introduced within the female sockets provided in the hyperthermia apparatus (not shown). In case it is desired to introduce a medicament, the plug 6 must be drawn out, introducing the medicament by the known technologies. The present invention has been described for illustrative, but not limitative purposes according to its preferred embodiments, but it is to be understood that modifications and/or changes can be introduced by those skilled in the art without departing from the relevant scope as defined by the enclosed claims.

Claims: CLAIMS 1. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, characterized in that it comprises a needle - pin element, a catheter made up of a biocompatible material semirigid sheath, conformed about said needle - pin element, and coupled with the same in such a way that the needle - pin element can be drawn out, at least a thermocouple, provided on the outer circumference of the semirigid sheath of said catheter, in known positions to the user, having the end realizing the reading point provided close to the sheath surface, coming into contact with the tissues, an application element for the catheter provided with a hole to allow the drawing out of the needle - pin element. 2. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to claim 1 , characterized in that said end realizing the reading point of said at least one thermocouple projects from said sheath of few hundredth of millimetres. 3. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to claim 1 or 2, characterized in that said sheath is provided with holes for the introduction of a medicament, each one preferably placed on the end of said at least one thermocouple, spaced from the same. 4. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that it is provided a plug element closing the posterior part of said catheter and supporting the needle when it is introduced within the same catheter. 5. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to claim 4, characterized in that said plug can be drawn out from the catheter. 6. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that said needle - pin element is made up of stainless steel. 7. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that said semirigid sheath of the catheter is made up of Teflon®. 8. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that said thermocouples are applied to the semirigid sheath by pressure - heat melting. 9. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that the number of thermocouple provided is between 1 and 15. 10. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that said application element of the catheter to the human body is made up of a PVC cap - ring, eventually inclinable, having an adhesive surface contacting the skin, welded to said semirigid sheath. 11. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that said application element is provided with a number of holes corresponding the number of thermocouples, in order to allow their exit, said thermocouples being collected in a further transparent sheath. 12. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to claim 11, characterized in that said transparent sheath is made up of Teflon®. 13. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that it is realized reusable or disposable. 14. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to one of the preceding claims, characterized in that the needle - pin element has a length between 1 and 8 cm. 15. Device for the invasive temperature measurement for surface and deep hyperthermia treatments, according to each one of the preceding claims, substantially as illustrated and described.

Inventors: MARSIGLIA GUGLIELMO, PAVONI PIERFRANCESCO, POSSENTI GIOACCHINO, MARSIGLIA, GUGLIELMO, PAVONI, PIERFRANCESCO, POSSENTI, GIOACCHINO
Applicants: MARSIGLIA GUGLIELMO, PAVONI PIERFRANCESCO, POSSENTI GIOACCHINO, MARSIGLIA, GUGLIELMO, PAVONI, PIERFRANCESCO, POSSENTI, GIOACCHINO
Application year: 1995
Main classification: G01K1
IPC codes: A61B5, G01K1