WO1999006111A1

WO1999006111A1 - Intracorporeal catheter comprising a device for measuring interstitial temperature and therapeutic apparatus using same

Info

Publication number: WO1999006111A1
Application number: PCT/FR1998/001711
Authority: WO
Inventors: François Lacoste; Eric Poincelet; Simon Carter Saint Clair; Olivier Lassal
Original assignee: Technomed Medical Systems
Priority date: 1997-08-01
Filing date: 1998-07-31
Publication date: 1999-02-11
Also published as: FR2766721B1; FR2766721A1

Abstract

The invention concerns an intracorporeal catheter comprising a device (11) emitting thermal radiation, and at least a device (14) measuring interstitial temperature, said catheter (10) comprising means guiding (16) said device measuring interstitial temperature (14). The invention is characterised in that, in the output zone of the device measuring interstitial temperature, part of the guide means forms a helical winding to guide the temperature sensor (14) following a predetermined angle (α) resulting in a predetermined position of the temperature sensor (14) end axial and radial relative to the intracorporeal catheter. The invention enables the in situ measurement of temperature in the organ tissues to be treated, for example the prostrate.

Description

Intracorporeal probe comprising an interstitial temperature measurement device and therapeutic treatment apparatus comprising application

The invention relates essentially to an intracorporeal probe comprising an interstitial temperature measurement device and a therapeutic treatment apparatus comprising an application thereof, in particular for treatment with physical agents. More particularly, the invention relates to an intracorporeal probe for treating the prostate and advantageously of the urethral type.

State of the prior art It is known in particular from the applicant's prior patent

US-A-5,509,929 itself constituting a CIP in patent US-A-5,234,004, and its French equivalents FR-A-2,639,238 and FR-A-2,693,116, a urethral probe for the treatment of the prostate via the urethral route, said probe being provided as a whole with a temperature sensor device, for example with optical fibers, measuring the surface temperature of the urethra. In the case of the device using this urethral probe described in this document, there is also provided a rectal temperature taking probe introduced into the rectum, making it possible to avoid any thermal damage to the rectal wall for good therapy.

The disadvantage of the solution recommended in this prior document of the depositor lies in the fact that there is no temperature measurement device inside the prostate, in situ, so that the temperature measurements carried out whether at the level of the urethral wall or the rectal wall constitute safety temperature measurements but no treatment efficiency.

On the other hand, it is known from document JP-A-2-121 675 published on May 9, 1990 on the basis of application JP-63-275 632 a probe for therapeutic treatment of the prostate comprising a plurality of needles heaters successively introduced interstitial into the prostate and can be combined with at least one temperature sensing element itself introduced interstitial. The solution recommended in this document is of a complex structure, difficult to implement since it requires successively introducing each heating needle interstitially into the prostate, which requires a period of time of implementation too long, and the recommended construction does not appear to allow precise insertion with risks of perforation at the level of the bladder. In addition, by having a needle dedicated to the temperature detection near the heating needles, the temperature measurement is necessarily disturbed by the nearby presence of the needles heating, so that temperature control is difficult and, on the other hand, the temperature measurement obtained with a temperature detection needle near the heating needle does not provide an indication of the general temperature in prostate. Furthermore, this device leads to the carrying out of a surgery which is traumatic, time-consuming to implement, and requiring work in the operating room because of its invasive nature by multiple needles and, if it was desired to reduce the number of 'needles, this would require reorienting the device and re-implanting it several times during treatment to treat the entire prostate.

A more recent document WO 96/36288 describes a solution similar to that described in the previous document JP-A-2-121 675, by presenting various embodiments allowing an interstitial introduction of a needle element dedicated to temperature detection . The provision of the means for guiding the temperature sensing needle element is not provided to ensure safe and reliable orientation of the temperature sensing needle element, at a predetermined orientation angle relative to the probe axis.

Aims of the invention

The main object of the present invention is therefore to solve the new technical problem consisting in providing a solution which makes it possible to carry out a treatment by natural means, non-invasive on the part of the transmitter, while being capable of measuring the temperature. in situ in the organ to be treated and to control the thermal emission power to the temperature measurement thus detected, at a safe and reliable angle of orientation relative to the axis of the probe, without requiring relocation in during treatment, the installation being done once and for all, and this with physical agents.

Another main object of the present invention is to solve the new technical problem consisting in the supply of a solution which makes it possible to carry out a heat treatment of the prostate by non-invasive route using a natural cavity, in particular the urethra, with a radiant element having a non-invasive thermal effect while allowing a temperature measurement in situ inside the tissues of the organ to be treated, here the prostate, at a safe and reliable orientation angle relative to the axis of the probe, and without requiring temperature control in the rectum, unlike previous solutions.

The present invention also aims to solve the new technical problems stated above in a particularly simple, reliable manner, usable on an industrial and medical scale.

Thus, according to a first aspect, the present invention provides an intracorporeal probe comprising a radiant element having a thermal effect capable of generating thermal energy for processing tissues located in the vicinity of the probe, and comprising at least one device for measuring temperature by interstitial channel, said probe comprising means for guiding the temperature measurement device by interstitial channel, characterized in that, in the exit zone of the temperature measurement device, part of the guide means forms a helical type winding for guiding the temperature measuring device at a predetermined angle leading to the obtaining of a predetermined position of the end of said temperature measuring device axially and radially with respect to the intracorporeal probe.

According to a currently preferred embodiment, the aforementioned intracorporeal probe comprises an orientation marking means, preferably substantially at the level of a generator of the intracorporeal probe, making it possible to obtain a precise angular orientation of the relatively temperature measuring device. to the organ to be treated.

According to yet another advantageous embodiment of the invention, the means for guiding the temperature measuring device comprise a tubular element containing a temperature measuring device proper mounted so as to be able to move in axial translation inside. of the latter, said tubular element being disposed at least at its free outlet end of the temperature measuring element at a predetermined angle relative to the longitudinal axis of the intracorporeal probe, so as to provide guidance safe and reliable angular orientation of the output of the temperature measuring device with precise positioning inside the tissues of the organ to be treated surrounding the intracorporeal probe.

According to an embodiment currently preferred, the tubular element comprises, in the outlet zone of the temperature measurement device, a winding of helical type, thus constituting the part of the aforementioned guide means in winding of helical type. According to an even more preferred embodiment, the helical winding in the outlet zone of the temperature measuring device ensures an angular orientation of an angle of at least about 45 ° at the exit of the temperature measuring device ensuring the good introduction of the temperature measurement device into the tissues.

According to another advantageous embodiment of the invention, the temperature measuring device comprises a filiform element which extends to the outside of the intracoφoreal probe so as to be accessible and therefore visible from the outside and in this case advantageously includes a means of marking the insertion position, which can for example be graduated to measure the insertion distance of the temperature measurement device interstitially in the tissues surrounding the intracoφorelle probe, and possibly also includes a stop member ensuring a safe and reliable stop in the desired position.

According to yet another advantageous embodiment of the invention, the above-mentioned filiform element is chosen from a thermocouple, or an optical fiber comprising at its free end a temperature sensor proper, preferably an optical fiber comprising such a sensor, due to its non-interference with an electromagnetic field which can be used to generate thermal energy. According to another advantageous embodiment of the invention, the aforementioned intracoφorelle probe is a probe comprising a heat treatment device emitting an energy chosen from microwave, ultrasonic, laser, or electrical energy.

According to yet another currently preferred embodiment of the invention, the aforementioned intracoφoral probe is a urethral probe for the treatment of the prostate by urethral route. In this case, this urethral probe comprises at its front part a locking means in position, preferably comprising an inflatable balloon of the Foley type making it possible to block the urethral probe in position at the base of the bladder, avoiding any possibility of untimely withdrawal . For this position, the heat treatment device is placed inside the prostate or at the level of the bladder neck. In this application to the prostate, the means for guiding the temperature measurement device ensure that it is guided inside the prostate tissue in a precise position axially and radially for which it is desired to measure the exact heating temperature. tissue while also ensuring a precise and reliable treatment time period. Preferably, the heat treatment device makes it possible to reach a temperature in a temperature zone of at least between 50 ° and 60 ° C, a temperature range in which it is sought to heat the tissues of the organ concerned in order to necrose them. According to another advantageous embodiment of the invention, the aforementioned intracoφorelle probe also comprises means for thermostating, in particular cooling making it possible to preserve the walls in contact with the probe, and, in the case of the treatment of the prostate, the intraprostatic urethral wall. According to yet another particular embodiment of the invention, the aforementioned tubular element can be arranged in the mass of the intracorporeal probe so as not to project externally on the surface of the intracoφorelle probe, thereby avoiding injuring the walls the natural path in which the probe is inserted and the outlet of which has the aforementioned predetermined angle relative to the longitudinal axis, or a generator of the probe. According to a second aspect, the present invention also covers a heat treatment apparatus comprising such an intracoφoral probe as defined above.

Other objects, characteristics and advantages of the invention will become clear in the light of the explanatory description which follows, given with reference to the appended drawings representing a currently preferred embodiment of the invention given simply by way of illustration and which therefore cannot in any way limit the scope of the invention. However, the embodiment shown in the drawings is an integral part of the present invention and therefore of the present description as well as any characteristic which appears to be new compared to any prior art. In the drawings:

- Figure 1 shows a partial longitudinal side view of the front part of an intracoφorelle probe of the invention, allowing to see the tubular element at the outlet of the temperature measuring device, this temperature measuring device being itself shown in the working position after having exited a distance D from the tubular element, according to a precise angular orientation α;

FIG. 2 represents an axial section showing the possible position of several tubular elements serving as protection and guide for several temperature measurement elements, as well as the device for locating the angular orientation position of the intracoφorelle probe, here according to a generator of said probe; FIG. 3 represents an embodiment of the intracorporeal probe according to the invention, constituting here a urethral probe inserted into the prostate for a heat treatment of the prostate, in the working position, and comprising for example two tubular guide elements and orientation of two temperature measurement devices preferably constituted here by optical fibers, opening out substantially diametrically opposite with respect to the probe;

FIG. 4 represents temperature curves obtained respectively by interstitial measurement according to the invention, curve 1, by rectal route, curve 2, by urethral route, curve 3, and showing the temperature curve of the thermostating liquid, curve 4, as well as the microwave energy delivery curve, which we see delivered in steps up to the maximum power of 70 watts, curve 5, as a function of the duration of the heat treatment in minutes and on the abscissa, for a microwave frequency at 1296 MHz, the right of the ordinates on the left giving the temperature in degrees Celsius and the right of the ordinates on the right giving the power expressed in watts (W); and

FIG. 5 represents an enlarged view of the end of the temperature detection device of the boxed area V in FIG. 1.

With reference to the figures, first of all to FIGS. 1 and 2, an intracoφoral probe according to the present invention is represented by the general reference number 10.

This intracoφorelle probe 10 comprises a front part 10a and a rear part 10b which extends naturally to the outside of the body. This intracoφorelle probe comprises a device 11 emitting thermal radiation, here not shown in FIG. 1, for a better understanding of the figures but which is mounted in section in FIG. 2, and is preferably positioned in a coaxial light 12. This thermal radiation device can be chosen from the group consisting of a microwave radiant element, an ultrasonic radiant element, a laser radiant element, and a radiant radiation of the electric electrode type. Within the framework of the invention, a microwave radiant element is currently preferred which makes it possible to emit microwave radiation easily penetrating the tissues in order to deliver microwave thermal energy there. Currently preferred microwave frequencies are either about 915 MHz, about 1,296 MHz or about 2,450 MHz.

On the other hand, this intracoφorelle probe advantageously comprises at least one interstitial temperature measurement device 14. In the context of the invention, the interstitial temperature measurement device 14 is arranged to axially displaceable, that is to say displaceable in axial translation, in a tubular element 16 which protrudes outside the coφs and which can thus be controlled from outside the coφs. The temperature measuring device 14 is preferably locatable by ultrasound, before the start of treatment and during treatment so as to precisely control its position.

In the context of the invention, the tubular element 16 is mounted relative to the intracoφorelle probe, that is to say on or preferably in the mass of the probe 10, so as to provide guidance and angular orientation precise relative to the longitudinal axis of the probe, as shown. According to a currently preferred embodiment, the tubular element comprises at least in the vicinity of its free end portion 16a a helical type winding H that can be seen clearly in Figure 1. This helical winding ensures a safe and reliable guidance of the temperature measuring element, and especially in the case where it comprises at least one optical fiber while avoiding any damage to this optical fiber by not respecting its radius of curvature, and on the other hand by ensuring a good angle of incidence of interstitial penetration into the surrounding tissues of the organ to be treated. According to a currently preferred embodiment, the incident angle is at least equal to 45 ° relative to the longitudinal axis of the probe or relative to a generator which is parallel to it, again as shown in FIG. 1.

According to another advantageous embodiment of the invention, several tubular elements 16 can be provided, each containing at least one temperature measuring device 14, angularly offset around the circumference of the probe, as shown in FIG. 2. For example , according to a currently preferred embodiment, the diameter of the temperature measuring device, when it is constituted by an optical fiber, is of the order of 0.5 mm and the outside diameter of the tubular element is less than 1 mm. The use of an optical fiber is advantageous on the one hand because it is rigid and on the other hand because the optical fiber is biocompatible during the time of contact with the tissues of the organ to be treated.

According to another advantageous characteristic of this intracorporeal probe, this comprises at least one locking means 20 in position, generally constituted by an inflatable balloon 22, as is well known to those skilled in the art. In the case of a urethral probe intended to be introduced into the urethra for treatment of the prostate, the blocking means 20 comprising the inflatable balloon 22 is intended to be positioned at the base of the bladder for block the urethral probe in position at the base of the bladder, with the thermal radiation emitting device placed inside the prostate or at the level of the bladder neck for either treatment of the prostate or bladder neck, in particular like this is indicated in the applicant's prior patents US-A-5,234,004 and US-A-5,509,929 and their French equivalents FR-A-2,639,238 and FR-A-2,693,116 which are incorporated here by reference in all of them.

This intracoφorelle probe 10 can also comprise cooling means 30a and 30b which can for example comprise at least two channels occupying angular sectors, such as 32, 34, respectively of inlet and outlet of thermostatizing fluid, ensuring circulation of fluid in order to protect against excessive heating the surrounding tissues in contact with the probe and which one does not wish to treat, as is also described in detail in the prior patents of the applicant US-A-5,234,004 and US-A -5,509,929 and their French equivalents FR-A-2,639,238 and FR-A-2,693,116 which are once again incorporated by reference in their entirety and to which those skilled in the art can refer.

The intracoφoreal probe described above can thus form part of a heat treatment apparatus, the main units of which are represented in FIG. 3 symbolically by the block 50 representing the central control unit controlling a device 60 for controlling the supply of flow rate and in temperature of the thermostating fluid, as well as a device 70 for controlling the power of thermal energy emitted by the device generating thermal energy, and for example preferably a device generating microwaves as a function of the data of temperature provided by the interstitial temperature detector device (s) 14. It will be observed that in FIG. 3, there is shown a currently preferred embodiment in which the intracoφoreal probe 10 constitutes a urethral probe introduced into the urethra 80 up to have its frontal part 10a penetrating into the bladder 90 from which the two depart x ureters 92, 94 joining the two kidneys. When the front part 10a enters the bladder 90, the inflatable balloon 22 is inflated, through an inflation channel 23, FIG. 2, and a urethral probe 10 is withdrawn until it is blocked on the base 90b of the bladder, as shown in FIG. 3. In this position, the device emitting thermal radiation 11, present in the central coaxial orifice 12 of the probe, is in a predetermined position relative to the prostate. Here, it is represented with its maximum thermal emission point E at the level of the bladder neck 110. This emission device according to the invention is preferably a single coaxial microwave antenna.

According to the present invention, as described with reference to FIGS. 1 and 2, the probe 10 also comprises at least one, here for example two, temperature measurement devices respectively referenced 14 mounted axially displaceable in translation or in sliding at interior of the tubular elements 16 having their end portion in helical winding. These temperature measuring devices are naturally disposed hidden inside the tubular elements 16 at the time of insertion of the probe into the urethra and deployed by axial sliding in translation after positioning, that is to say after swelling. of the balloon 22 and withdrawal until it is blocked on the base 90b of the bladder 90. The insertion limit of the temperature measurement elements 14 can advantageously be provided by the presence of marking and blocking means 120, outside of human coφs, and which can also cooperate with position marking means, for example comprising a graduated ruler and making it possible to precisely measure the penetration distance of the temperature measuring devices 14 interstitially in the tissues to be treat, here the prostate tissue, and measure the temperature for different depths of penetration. According to the present invention, with reference to FIG. 5, it is currently preferred to use a temperature measuring device 14 which has a bevelled end 14a, facilitating the penetration of the tissues, and advantageously made of a material allowing its precise location by ultrasound ultrasound. In the context of the present invention and of the embodiment presented in FIG. 5, this temperature measurement device 14 preferably comprises at least one optical fiber without respectively comprising a core 102 and a sheath 104 which is cut at a distance d from the end 14a to expose the core 102 of the optical fiber 100, the core 102 of the optical fiber 100 being covered and protected by an essentially tubular or cylindrical element 106, which comes to bear on the sheath 104 of the fiber optical and which at the opposite end 106a defines the bevelled part 14a of the temperature detection device 14.

The dimension of this tubular element 106 is greater than the dimension of the core 102 of the optical fiber, so as to allow a temperature sensor element 108 proper to be accommodated and which is advantageously made of a material consisting of a mixture of phosphorus powder and crosslinkable resin in the crosslinked state, constituting a very effective temperature sensor, which therefore has the determining advantage of being visible and detectable by ultrasound and therefore by ultrasound ultrasound. It is thus understood that the invention makes it possible to have in a precise and reliable manner the free end of temperature detection in radial and axial position relative to the probe. According to a currently preferred embodiment, the measuring end of the temperature measuring device is disposed at a predetermined distance from the plane defined by the maximum heating plane of the thermal radiation device 11, this plane being able to be simply defined by the plane perpendicular to the longitudinal axis of the probe which passes through the point E of maximum thermal emission by the thermal radiation device 11.

In the context of the invention, it is also advantageous to provide means 40 for marking the angular orientation of the probe, inscribed in the mass of the probe, as clearly visible in FIG. 2, and preferably arranged opposite or in contrast to an organ that is particularly to be monitored, such as the rectum for example in the treatment of the prostate P. In the case of the treatment of the prostate P, it is preferred that the locating means 40 be arranged opposite the rectum, taking into account that the patient is generally disposed on the back, which facilitates the visualization of the marking means 40.

Thanks to the invention, which makes it possible to measure the temperature of the tissues inside the heated zone in a precise and reliable manner, it is possible to dispense with a rectal temperature measurement. On the other hand, by the precise and reliable measurement in situ of the temperature of heating of the tissues inside the prostate, it is possible to know precisely the onset of tissue necrosis and the time necessary to ensure this necrosis. In the context of the invention, it is preferred to carry out tissue necrosis at a temperature between approximately 50 ° C. and approximately 60 ° C. Therefore, it is possible to monitor automatically by the control control 50 the minimum threshold for reaching a temperature of 50 ° C. and to control the maintenance of the temperature in this temperature zone for a minimum duration of necrosis of for example about 10 min and, consequently, to reduce the treatment time from typically 60 min today to about fifteen minutes to thirty minutes with this principle of treatment. The invention therefore makes it possible to achieve a decisive improvement in the heat treatment of organs and in particular in the heat treatment of the prostate, especially in the treatment of obstructive symptoms of the bladder neck and also in the treatment of benign prostate adenoma or BPH.

The invention also includes all the means constituting technical equivalents of the means described as well as their various combinations.

Claims

1. intracoφorelle probe (10) comprising a thermal radiant element (11) capable of generating thermal energy for processing tissues, located in the vicinity of the probe, and comprising at least one interstitial temperature measurement device (14), said probe (10) comprising means for guiding (16) the interstitial temperature measuring device (14), characterized in that, in the exit zone of the temperature measuring device, part of the guiding means ( 16) forms a helical type winding to guide the temperature measuring device (14) at a predetermined angle (α) leading to obtaining a predetermined position of the end of said temperature measuring device (14) axially and radially with respect to the intracoφorelle probe (10).

2. Probe according to claim 1, characterized in that the guide means (16) of the temperature detector device (14) comprise a tubular element containing a temperature measurement device proper (14) mounted so as to be able to move in axial translation inside thereof, said tubular element (16) being disposed at least at its free outlet end (16a) of the temperature measuring element (14) at a predetermined angle (α ) relative to the longitudinal axis of the intracoφorelle probe (10), so as to ensure safe and reliable guiding of the angular orientation of the outlet of the temperature measuring device (14) with precise positioning inside the tissues of the organ to be treated surrounding the intracoφoral probe (10).

3. Probe according to claim 2, characterized in that the tubular element (16) comprises in the outlet zone (16a) of the temperature measuring device (14), a winding of helical type (H), thus constituting the part of the aforementioned guide means in helical type winding.

4. Probe according to claim 3, characterized in that the helical winding (H) in the outlet area of the temperature measuring device (14) provides an angular orientation of an angle (α) of at least about 45 ° at the outlet of the temperature measuring device (14).

5. Probe according to one of the preceding claims, characterized in that the temperature measuring device (14) comprises a filiform element which extends to the outside of the intracoφorelle probe (10) so as to be accessible and therefore visible from the outside and advantageously comprises a marker means (122) of the insertion position, which can for example be graduated for measure the insertion distance of the temperature measuring device (14) interstitially in the tissue surrounding the intracoφoreal probe (10).

6. A probe according to claim 5, characterized in that the threadlike element of the temperature measuring device (14) also comprises a stop member (120) ensuring a safe and reliable stop in the desired position.

7. A probe according to claim 5 or 6, characterized in that the aforementioned filiform element is chosen from a thermocouple and an optical fiber, preferably an optical fiber.

8. Probe according to one of the preceding claims, characterized in that it comprises an orientation marking means (40), preferably substantially at the level of a generator of the intracoφorelle probe, making it possible to obtain an angular orientation of the temperature measuring device (14) relative to the organ to be treated (P).

9. Probe according to one of the preceding claims, characterized in that it comprises a heat treatment device (11) emitting an energy chosen from microwave, ultrasonic, laser or electric energy.

10. Probe according to one of the preceding claims, characterized in that it is a urethral probe for the treatment of the prostate by urethral route.

11. Probe according to claim 10, characterized in that it comprises at its front part (10a) a locking means in position (20), preferably comprising at least one inflatable balloon (22) of Foley type making it possible to block the urethral probe in position at the base (90b) of the bladder (90), avoiding any possibility of inadvertent removal, so that for this arrangement, the heat treatment device (11) is disposed inside the prostate or at the level of the bladder neck (110).

12. Probe according to one of the preceding claims, characterized in that the thermal treatment device (11) makes it possible to reach a temperature in a temperature zone of at least between 50 ° and 60 ° C, temperature range in which we seek to heat the tissues of the organ concerned for necrosis.

13. Probe according to one of the preceding claims, characterized in that it also comprises means for thermostatization (32, 34), in particular for cooling, making it possible to preserve the walls in contact with the probe (10), and, in the case of prostate treatment (P), the intraprostatic urethral wall (80).

14. Probe according to one of the preceding claims, characterized in that the aforementioned tubular element (16) is disposed in the mass of the intracoφorelle probe so as not to project externally on the surface of the intracoφorelle probe (10), thus avoiding injuring the walls of the natural path in which the probe is inserted, and the outlet (16a) of which has the aforementioned predetermined angle (α) relative to the longitudinal axis, or a generator, of the probe (10 ).

15. Probe according to one of claims 1 to 14, characterized in that the temperature measuring device (14) has a beveled end (14a) facilitating the penetration of tissue, and advantageously is made of a material allowing its precise location by ultrasound ultrasound.

16. A probe according to claim 15, characterized in that the temperature measuring device (14) comprises an optical fiber (100) whose sheath (104) has been removed near its free end and replaced by a tubular element (106 ) surrounding the core (102) of the optical fiber (100) and leaving a space for positioning a sensor (108) proper, preferably made of a material comprising a mixture of powdered phosphorus and a resin crosslinkable with crosslinked state.

17. Heat treatment apparatus, characterized in that it comprises an intracoφorelle probe (10) as defined in any one of the preceding claims, preferably comprising a control unit (50) controlling a device (60) for controlling the flow and temperature supply of the thermostating fluid in the thermostating means (32, 34) as well as a control device (70) of the thermal energy power emitted by the thermal energy generating device , and for example preferably a microwave generator device, as a function of the temperature data supplied by the interstitial temperature measurement device (s) (14).