This application is based on and claims priority under 35 U.S.C. § 119 with respect to Japanese Application No. 2003-197370 filed on Jul. 15, 2003, Japanese Application No. 2003-202544 filed on July 28, 2003 and Japanese Application No. 2003-205115 filed on Jul. 31, 2003, the entire contents of all of which are incorporated herein by reference.
The present invention generally pertains to a medical treatment apparatus. More particularly, the invention relates to an energy treatment apparatus which is, for example, adapted to be inserted into a blood vessel, a digestive tract such as esophagus, rectum, etc., or a cavity or lumen of a living body such as urethra, abdominal cavity, thoracic cavity, etc., or surgically pressed against a living body tissue or pressed against the body surface and which irradiates the body tissue with an energy such as ultrasound, a laser beam, etc. for the purpose of relatively high-temperature treatment of a tumor such as cancer, or BPH (benign prostatic hyperprasia) or the like.
Thermotherapeutic technologies (hyperthermia, high-temperature treatment, ablation, vaporization technique) are known in which an elongate insertion portion is inserted into a living body, either by utilizing a body cavity or by applying a small incision to the living body. A living body tissue, including a lesion, is irradiated with energy such as ultrasonic waves or a laser beam from the insertion portion to annihilate the tissues at the lesion site or the surrounding tissues including the lesion site through alteration, sphacelation, coagulation, cauterization or vaporization, thereby achieving treatment.
In these technologies, generally, the treatment is carried out by directly irradiating the surface layer of the body tissue or the lesion site located in the vicinity thereof with the energy. The technologies are utilized also for thermotherapy of a lesion site located in the depth of a living body tissue such as, for example, the prostate.
U.S. Pat. No. 6,379,347, U.S. Pat. No. 6,562,029 and Japanese Application Publication No. 2000-319 disclose examples of a medical energy irradiation apparatus applied to such thermotherapy. U.S. Pat. No. 5,743,863 and U.S. Pat. No. 5,676,692 disclose treatment apparatus applied to high intensity focused ultrasound (HIFU) therapy.
When a medical energy irradiation apparatus is to be applied to the treatment of the prostate, for example, the treatment is generally conducted in the following procedure. The doctor treating the prostate inserts an insertion portion of the medical energy irradiation apparatus into the rectum, sets the position of an emission unit to the prostate, adjusts the position of the emission unit toward the target site (the site to be treated), and irradiates the target site with the energy. This series of operations is generally performed by the doctor while observing the treatment condition through ultrasonic image diagnosis.
The above-mentioned conventional energy irradiation apparatus for thermotherapy is configured to concentrate irradiation at the target site with the energy, for example, the laser beam emitted from the emission unit. In order to treat the target site while maintaining the target site in the above-mentioned heated state at the time of laser irradiation, it is necessary to enhance the utilization efficiency of energy. To enhance the energy utilization efficiency, it is necessary to raise the output of emission, which may produce damage to normal tissues (i.e., tissue other than at the target site).
A need thus exists for an energy treatment apparatus which is better suited to enhancing the utilization efficiency of energy emitted from an emission unit while also enhancing the accumulation of energy at the target site and suppressing the emission output.
The energy treatment apparatus described here is adapted for use in irradiating a living body tissue with energy. According to one aspect, the apparatus can include an energy emission unit for emitting energy to irradiate a target site of living body tissue, and reflection means disposed at a position opposite to the energy emission unit to reflect at least some of the energy emitted from the energy emission unit toward the target site.
According to another aspect, an energy treatment apparatus for irradiating living body tissue with energy comprises an energy emission unit for emitting energy toward a target site of living body tissue, reflection means disposed at a position opposite to the energy emission unit to reflect energy emitted from the energy emission unit toward the target site, and moving means for moving the energy emission unit to vary a position of the energy emission unit.
Another aspect involves an energy treatment apparatus for irradiating living body tissue with energy comprising energy emission means for emitting energy toward a target site of living body tissue along a plurality of different routes, and reflection means disposed in opposing relation to the energy emission means for receiving at least some of the energy emitted along the different routes from the energy emission means and for reflecting at least some of the energy emitted along the different routes from the energy emission means towards the target site.
In accordance with another aspect, an energy treatment apparatus for irradiating living body tissue with energies comprises a first energy emission unit for emitting energy having a first frequency toward a target site of living body tissue, a second energy emission unit for emitting energy having a second frequency different from the first frequency toward the target site of living body tissue, and reflection means positioned relative to the first and second energy emission units for reflecting at least a portion of the energy of the first and second energy emission units toward the target site of living body tissue so that emitted energy from the first energy emission unit and reflected energy from the first emission unit that is reflected by the reflecting means produces a first standing wave between the first emission unit and the reflection means, and emitted energy from the second energy emission unit and reflected energy from the second energy emission unit that is reflected by the reflecting means produces a second standing wave between the second emission unit and the reflection means.
An additional aspect involves an energy treatment apparatus for irradiating living body tissue with energies comprising energy emission means for emitting energy having first and second different frequencies toward a target site of living body tissue, and reflection means positioned relative to the energy emission means to reflect at least a portion of emitted energy emitted by the energy emission means toward the target site of living body tissue.
According to a further aspect, an energy treatment apparatus for irradiating living body tissue with energy comprises energy emission means for emitting energy to irradiate a target site of living body tissue, reflection means disposed relative to the energy emission means to reflect at least a portion of emitted energy emitted from the energy emission means toward the target site, and control means for controlling the energy emission means so that reflected energy reflected by the reflecting means and the emitted energy emitted by the energy emission means are superposed on one another at the target site.
In accordance with another aspect, an energy treatment apparatus for irradiating living body tissue with energy comprises a transuretheral energy emission unit for emitting energy to irradiate a target site of a living body tissue and a transrectal reflection means disposed relative to the transuretheral energy emission unit to reflect at least a portion of emitted energy emitted from the transuretheral energy emission unit toward the target site, with the target site being sandwiched between the transuretheral energy emission unit and the transrectal reflection means.
By disposing reflection means at a position opposite to the emission unit, it is possible to utilize both the energy from the energy emission unit and the energy reflected by the reflection means. In addition, it is possible to irradiate the target site with the energy from the energy emission unit, and to irradiate the target site with both the energy partly penetrating through the target site and reflected by the reflection means and the energy from the energy emission unit. Therefore, it is possible to efficiently enhance the energy accumulation density at the target site, and to weaken the energy accumulation density at body tissues other than the target site. The emitted energy emitted from the energy emission unit and the reflected energy reflected from the reflection means can be superposed on each other at the target site.
An arranging apparatus can also be provided to arrange both a main body including the energy emission portion and the reflection means. The arranging apparatus preferably includes a holding unit for the main body including the energy emission unit, a holding unit for the reflection means, and a mechanism for regulating the relative positions of the energy emission unit and the reflection means. In addition, an arrangement control means can be provided for controlling the arranging apparatus. The arrangement control means preferably performs control such that the emitted energy emitted from the energy emission unit and the reflected energy reflected from the reflection means are superposed on each other at the target site.
The arranging apparatus can be configured to change the direction of the energy emission unit, and can be provided with reflection control means for controlling the reflection means. The energy treatment apparatus can also include an emission control means for controlling the emitted energy from the energy emission unit. The emission control means can control the irradiation pattern for concentrating the emitted energy into the target site, the irradiation output, and the irradiation time.
When provided, the emission control means preferably controls the irradiation pattern in such a way that the target site is intermittently irradiated with the emitted energy from the emission unit. Also, the emission control means can preferably control the irradiation pattern so that the energy intermittently emitted from the energy emission unit and the reflected energy reflected by the reflection means reach the target site simultaneously.
The reflection means can include a fixed reflective surface or a variable reflective surface, and can be configured so that the curvature of the reflective surface and its radius of curvature are variable so as to efficiently reflect the energy. The reflection means can be provided with an energy detection means for detecting the quantity of energy reaching the reflection means from the energy emission unit. The reflection means can also be provided with air bleeding means for discharging air between the reflection means and living body tissue.
The energy treatment apparatus can additionally include cooling means for cooling at least one of the energy emission unit and living body tissue contacted by a main body including the energy emission unit. Cooling means can also be provided for cooling at least one of the reflection means and living body tissue contacted by the reflection means. Additionally, cooling control means can be employed to control the cooling means.
A controller can be provided for controlling the movement control means. Also, a controller can be provided to control the arrangement control means or to control both the arrangement control means and the emission control means. A controller can control the reflection control means or can control at least two of the reflection control means, the arrangement control means, and the emission control means. Also a controller can control the cooling control means or can control at least two of the cooling control means, the arrangement control means, the emission control means, and the reflection control means.
The energy treatment apparatus is preferably configured so that a main body including the energy emission unit includes means for converging, collimating, or diverging the spreading angle of the emitted energy. The main body having the energy emission unit can also be provided with observation means for positioning and for observing the inside of a living body.
Also, a balloon capable of expansion and contraction for position fixation can be provided at the surface of the main body including the energy emission unit or at the surface of the reflection means, or at the surface of both the main body and the reflection means.
A surface layer including a hydrophilic polymer material cab be provided at the surface of a main body having the energy emission unit or at the surface of the reflection means, or at the surface of both the main body and the reflection means.
The form of energy which can be employed includes ultrasounds, laser beams and others. Ultrasound energy has depth-reaching capability and is thus beneficial to use in cases where the energy treatment apparatus is applied, for example, to the prostatic treatment or the like which requires or benefits from the depth-reaching capability of the energy.
A further aspect involves a method of treating living body tissue comprising emitting energy at a target site, with at least a portion of the emitted energy passing through the target site, and reflecting at least a portion of the emitted energy which has passed through the target site back towards the target site.
The foregoing and additional features will become more apparent from the following detailed description considered with reference to the accompanying drawing figures in which like elements bear like reference numerals.
The energy treatment apparatus 1 according to one embodiment comprises an applicator 2 in the form of a generally elongated insertion portion, an energy emission unit 3 disposed in the applicator to irradiate living body tissue with energy, a reflection means 4 disposed opposite the emission unit 3 to reflect the energy emitted from the emission unit 3, and a controller 5 which comprises a control unit for designating an irradiation pattern for concentrating the energy into or at a target site, or site to be treated, 80 of a living body tissue, and other control units. The reflection means 4 is comprised of a reflector 6 having a flat surface or concave surface for substantially reflecting the energy, and an operating rod 7 for inserting the reflector 6. In the illustrated version, the reflector 6 is integrally provided at the distal end of the operating rod 7.
The emitted energy can take a variety of forms, including ultrasounds, laser beams, electromagnetic waves having directivity, etc. The energy treatment apparatus 1 in the embodiments described here is applied as an ultrasonic treatment apparatus using ultrasounds having a relatively high depth-reaching capability as the energy. Therefore, an ultrasonic oscillator constituting the emission unit 3 is provided on the distal end side in the applicator 2. Ultrasound is emitted from the ultrasonic oscillator 3. As examples of the ultrasonic oscillator, devices can be employed whose shapes are varied upon application of voltages thereto, such as piezoelectric ceramics (PZT, barium titanate, etc.), piezoelectric polymers (PVDF, P(VDF-TriFE), etc.) and the like.
The irradiation pattern designated or set by the controller 5 can be such that, by way of cooperation of the ultrasound emitted from the ultrasonic oscillator 3 with the reflected ultrasound reflected by the reflector 6, the intensity of the ultrasound is higher at the target site 80 and is lower at other sites. In this embodiment, the ultrasound is radiated from the ultrasonic oscillator 3 toward the target site 80, and a part of the ultrasound penetrates through the target site 80 and is reflected by the reflector 6 so that the reflected ultrasound is again radiated to the target site 80.
As will be described below in more detail, the applicator 2 and the reflection means 4 are arranged to be movable so that the distance therebetween can be controlled. Therefore, they are each preferably formed of a material having a comparatively high hardness; for example, they may be formed of stainless steel or the like. Materials for constituting the applicator 2 will be described later.
An example of the principle associated with the use of the energy treatment apparatus 1, or ultrasonic treatment apparatus, according to this embodiment will be described. The following description will consider an example in which the energy treatment apparatus 1 is applied to the treatment of prostatic cancer or BPH.
As shown in
In the present embodiment, the ultrasonic energy is accumulated at the target site 80 in such a manner that the temperature at the target site 80 is controlled to within a temperature range in which a high-temperature treatment can be performed and, yet, vaporization is not caused, preferably about 55° C. to 100° C., more preferably about 70° C. to 90° C.
As shown in
The irradiation pattern designated by the controller 5, in the present embodiment, is such a pattern that the ultrasound 85 from the ultrasonic oscillator 3 is intermittently radiated to the target site 80, a part of the ultrasound penetrates through the target site 80 and is reflected by the reflector 6, with the reflected ultrasound 85′ and the next ultrasound 85 from the ultrasonic oscillator 3 being synchronously radiated to the target site 80. Namely, the ultrasound 85 from the ultrasonic oscillator 3 and the reflected ultrasound 85′ are superposed on each other at the target site 80.
One example of the irradiation pattern will now be described. In the present example, the ultrasound pulse train 85 is oscillated in a pulsed form from the ultrasonic oscillator 3, and the next ultrasound pulse train 85 is radiated to the target site 80 synchronously with the arrival at the target site 80 of the reflected ultrasound 85′ reflected by the reflector 6 so that the two ultrasounds (i.e., the reflected ultrasound 85′ from one pulse train and the direct ultrasound 85 from the next pulse train) are superposed on each other at the target site 80, resulting in enhanced intensity of the ultrasound.
The first ultrasound pulse train (fundamental wave) 851 radiated from the emission unit 3 is reflected by the reflector 6, and then reaches the target site 80. The second ultrasound pulse train (delayed wave) 852 is radiated at such a timing that 9 it will be superposed on the reflected first ultrasound pulse train 851′ at the target site 80, namely, at the position of circles in the graph, resulting in enhancement of the energy density.
Next, referring to
Here, in the case of ultrasound, a high-temperature treatment can be performed under the following conditions.
1. The frequency of ultrasound is in the range of from 100 kHz to 50 MHz, more desirably from 1 to 5 MHz.
2. The distance L from the emission unit to the reflector is in the range of from 0.1 to 10 cm, more desirably from 1 to 6 cm.
3. The range of wavelength, in view of λ=v/f, v=1530 m/sec and the frequency in condition 1, is from 15 to 0.03 mm, more desirably from 1.5 to 0.3 mm.
4. The cyclic period T, in view of condition 1 and condition 2, is in the range of from 1.3 to 130 μsec, more desirably from 13 to 80 μsec.
5. The pulse emission time t1 can be in the range of from {fraction (1/20)} to ½ times the cyclic period T, more desirably from {fraction (1/10)} to ⅓ times the cyclic period T.
Specifically, when the range of T is from 1.3 to 130 μsec, the range of t1 is from 1.3 μsec×{fraction (1/20)} to 130 μsec×½, more desirably from 1.3 μsec×{fraction (1/10)} to 130 μsec×⅓. When the range of T is from 13 to 80 μsec, the range of t1 can be from 13 μsec×{fraction (1/20)} to 80 μsec×½, more desirably from 13 μsec×{fraction (1/10)} to 80 μsec×⅓.
While ultrasound has been used in the above-mentioned example, the preferred or optimum conditions can be determined according to the purpose in the cases of performing a high-temperature treatment, for example by using lasers, electromagnetic waves, or the like.
Another example of the irradiation pattern will now be described. In this example, ultrasound is continuously oscillated from the ultrasonic oscillator 3, and the ultrasonic oscillator 3 is rotated about the axis of the applicator 2 so that the target site will be irradiated, apparently in a pulsed mode, with the ultrasound each time the ultrasonic oscillator 3 is rotated through one revolution. A high-temperature treatment using this irradiation pattern is preferable when applied, for example, to the treatment of the whole perimeter of the prostate in the case where sites other than the critical site of prostatic cancer are suspicious.
To perform the treatment here, the applicator 2 is inserted into the urethra 81, the reflector 6 is inserted into the rectum 82, the ultrasonic oscillator 3 is rotated about the axis of the applicator 2, and the target site of the prostate in the surroundings region of the urethra 81 is irradiated with ultrasound 85. The prostatic cancer site 80 is irradiated with the ultrasound 85 once per one revolution of the ultrasonic oscillator 3, and the other entire peripheral target sites are also similarly irradiated with the ultrasound 85 once per one revolution. The reflector 6 is moved as indicated by the chain-line while extending the rectum 82, in a manner corresponding to or coordinated with the rotation of the ultrasonic oscillator 3. By such operations, it is possible to perform thermotherapy over the whole perimeter of the prostate while concentrating the ultrasound into the target site. Incidentally, the transition region 83b to which the rectum 82 cannot be extended is not treated.
Next,
The controller 5 includes a control unit 91 composed of a CPU such as a microprocessor, and a data base 92 storing programs to be executed by the control unit 91 and various kinds of data. Various control mechanism are connected to the control unit 91. These include an emission control means 93 for setting a transmission output and an irradiation pattern for driving the emission unit 3, for example an ultrasonic oscillator, a cooling liquid control means 94 for supplying and draining a cooling liquid to and from the applicator 2 and the reflection means 6, an arrangement control means 95 for setting the distance between and the directions of the applicator 2 and the reflection means 4, a reflection control means 96 for controlling, for example, the radius of curvature of the reflector 6 of the reflection means 4, and an energy detection means 97 for detecting the intensity of the energy, for example ultrasound, emitted from the energy emission unit 3. Further, a monitor 98, which can be of the cathode ray tube or liquid crystal type, is provided as a display means for displaying information, for example the results of arithmetic operations of input information, etc.
As the cooling liquid control means 94, there is provided a means for circulatorily injecting and draining a cooling liquid to prevent surface layers of the living body tissues other than the target site, i.e., surface layers making contact with the applicator 2 and the reflector 6, from being undesirably excessively heated by the ultrasound emitted from the ultrasonic oscillator 3.
Where the ultrasonic oscillator is used as the emission unit 3, it is desirable to irradiate the target site 80 with the ultrasound while converging the ultrasound.
The reflection means 4 can take various forms, a number of which are described below. The reflection means 41 according to the embodiment shown in
A reflection means 42 according to another embodiment shown in
A reflection means 43 according to another embodiment shown in
The reflection means 44 shown in
Another embodiment of a reflection means 45 is shown in
A further reflection means 46 shown in
One end of the second reflector element 52 is rotatably attached to a shaft 54 integral with a folded connection portion 51A of the first reflector element 51, and the other end is attached to the shaft of a first rotatable gear 55 disposed on the same axis as the shaft 54. One end of the third reflector element 53 is rotatably attached to a shaft 56 integral with the folded connection portion 51A of the first reflector element 51, and the other end is attached to the shaft of a second rotatable gear 57 disposed on the same axis as the shaft 56. The first rotatable gear 55 is shaft-supported between an end portion of the first reflector element 51 and a base portion on the side of the operating rod 7. The second rotatable gear 57 is connected to a rotary shaft 58 disposed through the operating rod 7. The first and second rotatable gears 55, 57 mesh with each other. An operating lever 59, which may be operated manually by way of example, is attached to the rotary shaft 58. The operating rod 7 is provided with a housing 60, which is provided with a guide groove 61 for the operating lever 59, and the operating lever 59 is turned along the guide groove 61. Furthermore, a flexible film 38 for covering the whole part of the reflector 6 is provided in the same manner as in the above-described embodiment, and an injection tube 63 for injecting a cooling liquid through the housing 60 into the reflector 6 and a drain tube 64 for draining the cooling liquid are also provided. A portion of the reflection means 47 and the operating rod 7 are connected to each other through a connection means 65.
As mentioned above, this reflector 6 includes three reflector elements 51, 52, 53 which are generally folded onto each other or overlapping each other as shown in
The arranging apparatus 14 includes a first holding unit 102 for holding the reflection means 4 on a principal surface of a base 101, a second holding unit 104 supported on a support column 103 extending from one side of the base 101 and functioning to hold the applicator 2 at a position opposite to the first holding unit 102, and a position adjusting mechanism for adjusting the positions of the ultrasonic oscillator 3 and the reflection means 4. The first holding unit 102 holds the reflection means 4 so that the position and the direction of a spoon-shaped reflector 6 can be adjusted. For example, as shown in
The second holding unit 104 is comprised of a cover portion 104A and a fixed portion 104B, in the same manner as the first holding unit 102, so as to hold in a clamping type manner the applicator 2 which is circular in cross-section. The second holding unit 104 is supported-on a support member 108, which is vertically movable along the support column 103, and is vertically moved through the support member 108. The vertical movements can be controlled, for example, by a magnetic scale using a magnetic sensor. With this arrangement, the position of the second holding unit 104, and hence the distance between the reflection means 4 and the ultrasonic oscillator 3, can be set by use of the magnetic scale through operation of a handle 110 to move the support member 108 through a feed shaft having a feed screw. The position adjusting mechanism is comprised of means for respectively effecting vertical movements of the second holding unit 104, movement of the applicator 2 in the axial direction and turning of the applicator 2 about the axis in the second holding unit 104, and movement of the reflection means 4 in the axial direction, turning of the reflector about the axis of the operating rod 7 and movement of the operating rod 7 within the hatched region, in the first holding unit 102.
The applicator 2 provided therein with the ultrasonic oscillator 3 is connected to the controller 5 via a cable 112. The cable 112 includes an electric wiring, and cooling liquid feed/drain tubes for injecting and draining a cooling liquid into and from the region where the ultrasonic oscillator 3 is disposed inside the applicator 2. With respect to the reflection means 4, cooling liquid feed/drain tubes 113 for injecting and draining a cooling liquid and a signal wire extending from an output detection sensor are connected to the controller 5. The controller 5 includes a key operating unit, the above-mentioned control unit 91, the data base 92, and cooling liquid tanks and the like. The controller 5 is adapted to effect the control of the output of the ultrasound emitted from the ultrasonic oscillator 3, the control of the flow rates of the cooling liquid, the processing of a detection signal from the ultrasound sensor 35 at the reflector 6, the control of other functions (described later) when the other functions are provided, etc. A footswitch 114 may also be provided.
The energy treatment apparatus according to another aspect of invention aims at enhancing the concentration of energy on a target site by use of the basic configuration generally described above. This apparatus can comprise an elongate applicator, an energy emission unit disposed in the applicator, a reflection means disposed at a position opposite to the applicator to reflect the energy emitted from the emission unit, a controller for controlling the energy emission unit and the reflection means, and an arranging apparatus for arranging the applicator and the reflection means, with the energy emitted from the emission unit being collected into the target site by way of different routes at the time of treatment.
According to the energy treatment apparatus in this version, the energy emission unit and the reflection means are provided and the energy emitted from the emission unit is radiated to the target site by way of different routes, so that it is possible to concentratively irradiate the target site with the energy, without significantly heating the living body tissues other than at the target site. It is possible to heat the target site to a desired or relatively optimum thermotherapeutic temperature, and to perform thermotherapy in a relatively short time.
The energy treatment apparatus 101 shown in the embodiment of
The controller 5 includes a control unit 91 composed of a CPU such as a microprocessor, and a data base 92 storing programs to be executed by the control unit 91 and various kinds of data. The control unit 91 is connected to a movement control means 93 for driving the emission unit 3 (for example an ultrasonic oscillator), an emission control means 94 for setting an irradiation pattern, a cooling liquid control means 95 for supplying and draining a cooling liquid to and from the applicator 2 and the reflection means 6, an arrangement control means 96 for setting the distance between and the directions of the applicator 2 and the reflection means 4, a reflection control means 97 for controlling, for example, the radius of curvature of the reflector 6 of the reflection means 4, and an energy detection means 98 for detecting the intensity of the energy, for example, ultrasound, emitted from the energy emission unit 3 are connected to the control unit 91. Further, a monitor 99 of the cathode ray tube type or liquid crystal type, for example, is provided as a display means for displaying infromation including the results of arithmetic operations of input information, etc.
As described previously in connection with the apparatus shown in
When the ultrasonic oscillator is used as the emission unit 3, the ultrasonic oscillator is integrally arranged in an opening 121A in a base 121, with a cushioning material 122 therebetween as shown in
The base 121 is integrally provided with engagement pins 125 on both side surfaces of the distal end of the base 121 on the side opposite to the side of attachment to the arm 123. The engagement pins 125 are engaged respectively in engagement guide grooves 128 formed in a pair of guide plates 127 disposed inside the applicator 2. The guide grooves 128 are formed to be inclined at an angle θ moving from the distal end side toward the proximal end side of the applicator 2 along the axial direction of the arm 123. The base 121 integral with the ultrasonic oscillator 3 is moved along the guide grooves 128, with which the engagement pins 125 are engaged, as the arm 123 is moved. This causes the base 121 to be turned with the shaft 124 as a center. In this way, the angle a of an ultrasound emission surface 3a is varied. Specifically, a setting is made such that when the engagement pins 125 of the base 121 are located at the lower ends of the guide grooves 128, the ultrasound emission surface 3a is set at a predetermined angle +α, then the ultrasound emission surface 3a becomes parallel to the axis of the arm 123 (angle α=0°) when the engagement pins 125 are at intermediate position between the upper ends and the lower ends of the guide grooves 128, and thereafter the ultrasound emission surface 3a is set at an angle −α against the axis of the arm 123 when the engagement pins 125 are located at the upper ends of the guide grooves 128.
It is desirable that the normal living body tissues other than the target site, for example, the surface layer portions making contact with the applicator 2, are not significantly heated at the time of treatment. To achieve this result, the applicator 2 may be so configured that the arm 123 connected to the base 121 which is integral with the ultrasonic oscillator 3 has a pipe structure so that a cooling liquid can be injected into the applicator 2, particularly into the vicinity of the ultrasonic oscillator 3, through the arm 123. The cooling liquid can also be drained from the applicator 2 through a drain tube.
It is also desirable that the ultrasound emitted from the ultrasonic oscillator 3 is radiated in a converging manner to the target site 80. For this purpose, and in a manner similar to that described above in connection with
Referring to
First, the applicator 2 is inserted into the urethra 81 so that the ultrasonic oscillator 3, which is the emission unit provided at a distal end portion of the applicator 2, is located in the vicinity of the target site 80 to be irradiated. In addition, the reflector 6 is inserted into the rectum 82 through the use of the operating rod 7 and is located in the vicinity of the target site 80 at a position opposite to the ultrasonic oscillator 3.
Next, while driving the slide portion 129 of the drive unit constituting the movement control means 93 and thereby moving the ultrasonic oscillator 3 from a distal end portion of the applicator 2 toward a proximal end portion, the target site 80 is irradiated with the ultrasound emitted from the ultrasonic oscillator 3. A part of the ultrasound radiated to the target site 80 penetrates through the target site 80, is reflected by the reflector 6, and is again radiated to the target site 80. In the present embodiment, attendant on the movement of the base 121 integral with the ultrasonic oscillator 3 in the axial direction of the applicator 2 (i.e., the movement of the base 121 from the distal end side toward the proximal end side of the applicator 2), the engagement pins 125 are guided along the guide grooves 128. The ultrasonic oscillator 3 is thus turned so that the angle between the ultrasound emission surface 3a and the axis of the applicator 2 is changed from +α through 0 to −α, in the same manner as discussed above. The ultrasound from each turned position of the ultrasonic oscillator 3 is necessarily radiated to the target site 80. Therefore, only the target site 80 is always irradiated with the ultrasound in a concentrated manner, whereas body tissues other than the target site 80, for example surface layer portions, are relatively little heated. It is thus possible to heat only the target site 80. It is also possible to perform a high-temperature treatment by repeatedly reciprocating the ultrasonic oscillator 3 in the axial direction of the applicator 2 in this manner.
In the high-temperature treatment as described above, the emission unit shown in
Here, before ultrasound treatment, the direction of the emission unit 3 and the distance between the applicator 2 and the reflector 6 are set in a distance/direction setting unit 96. Also, as described above, the intensity of the ultrasound emitted from the emission unit 3 can be detected by an ultrasound sensor 35 constituting the ultrasound detection unit 98 provided at the reflector 6, with the detected intensity being fed back to the control unit 91, thereby regulating the ultrasound output of the emission unit 3. Furthermore, at the time of the ultrasound treatment, cooling liquid can be supplied through the cooling liquid control means 95 into the applicator 2 and into the reflector 6 as required.
The graph in
Curve II in
From curve I, it is clearly recognized that the ultrasound emitted from the ultrasonic oscillator 3 and the ultrasound reflected from the reflector 6 are superposed on each other at the target site P2, whereby the concentration of the ultrasonic energy is enhanced, and the ultrasonic energy density is gradually lowered as the distance from the target site P2 increases.
Where an ultrasound emission unit is used as the emission unit 3, the ultrasonic oscillator 103 is connected to a slide portion 129 of a drive unit through an arm 105 extending in the axial direction of the applicator 2. The ultrasonic oscillator 103 is reciprocated in the axial direction of the applicator 2 by the slide portion 129. The ultrasonic oscillator 103 is supported on the front surface side of a support portion 108, and the support portion 108 is fixed to the distal end of the arm 105.
On the other hand, the upper end of the mirror 104 is movably mounted to the upper end on the front surface side of the support portion 108 through a shaft 112. Engagement pins 109 projecting from both side portions of the lower end of the mirror 104 are engaged with guide grooves 111 formed in a pair of guide plates 110 disposed inside the applicator 2. The guide grooves 111 are formed so as to be inclined at a required angle 0 during movement from the distal end side toward the proximal end side of the applicator 2 along the axial direction of the arm 105. With the arm 105 moved, the engagement pins 109 are moved along the guide grooves 111 and so the angle of the mirror surface of the mirror 104 can be varied with the shaft 112 as a center.
It is desirable that normal body tissues other than the target site 80, for example surface layer portions, making contact with the applicator 2 are not significanty heated at the time of treatment. To achieve this result, the applicator 2 may be configured so that the arm 105 connected to the support portion 108 for the ultrasonic oscillator 103 is generally configured as a pipe or hollow member allowing a cooling liquid to be injected through the arm 105 into the applicator 2, particularly into the vicinity of the emission unit 3, with the cooling liquid beingdrained through a drain hole 113 formed in the slide portion 129.
The ultrasound emitted from the ultrasonic oscillator 103 is reflected by the mirror surface 104a of the movable mirror 104 to be radiated to the target site 80. In this case, an acoustic lens for converging the ultrasound may be attached to the ultrasound emission surface of the ultrasonic oscillator 103, with a ½ wavelength plate 22 therebetween in the same manner as above-described. As shown in
Referring to
Through rotation of the motor 135, the grooved cam 133 is rotated about the rotary shaft 134. In this case, the cam follower 138 is not rotated but slides in the groove 136. Since the rotary shaft 134 is eccentric relative to the groove 136, the rotation thereof causes the rod 137 (and the arm) to repeatedly undergo a translational movement (reciprocating movement).
The applicator 2 is inserted into the urethra 81, and, when the ultrasound emission unit 3 is located opposite to a target site 80 of the prostate 83, a one-sided balloon 161, which can be positioned at the opposite side relative to the emission unit 3 as illustrated, is expanded to bring the balloon into close contact with the upper surface of the urethra 81 in
The ultrasound emission unit 3 is reciprocated with the range indicated by arrows a as a stroke length. It is necessary for the emission unit 3 to be located on the distal end side relative to a first guide portion 162 when the emission unit is located on the most proximal side. In addition, it is desirable that when the emission unit 3 is located on the most distal side, the emission unit 3 does not exceed the distal end of a second guide portion 163 and the ultrasound passes through an opening 164.
The ultrasound is emitted to a lateral side relative to the longitudinal axis of the emission unit 3 (preferably at a right angle to the longitudinal axis of the emission unit) for an efficient irradiation. Here, the longitudinal axis of the emission unit 3 is always in the direction of a tangent to a circular arc drawn by the second guide portion 163. Therefore, the ultrasound irradiation direction is always directed substantially toward the center (the target site 80) of the circle including the circular arc. Therefore, when the target site 80 is irradiated with the ultrasound during reciprocation of the emission unit 3, the ultrasound emission position is always varied on the surface of the living body tissue in contact with the applicator 2, so that the irradiation time for the surface is short, and the quantity of heat generated there is accordingly relatively small. Additionally, the ultrasound is concentrated at the target site 80 located in the depth of the body tissue, so that only the depth portion can be thermally treated while preserving the surface of the body tissue.
The arranging apparatus 14 includes a first holding unit 142 for holding the reflection means 4 on a principal surface of a base 141, a second holding unit 144 supported on a support column 143 extending from one side of the base 141 and functioning to hold the applicator 2 oppositely to the first holding unit 142, and a position adjusting mechanism for adjusting the positions of the ultrasonic oscillator 3 and the reflection means 4. The first holding unit 142 holds the reflection means 4 so that the position and the direction of a spoon-shaped reflector 6 can be adjusted arbitrarily. For example, an operating rod 7 for the reflector 4 is adapted to be moved in the region indicated by the hatching on the first holding unit 142 so that it is held in a variety of desired positions while also be capable of being held at a rotational position.
The second holding unit 144 includes a cover portion 144A and a fixed portion 144B, in a somewhat similar manner to the first holding unit 142, so as to hold the applicator 2 which is circular in cross-section in a clamp type manner. The second holding unit 144 is supported on a support member 148 vertically movable along the support column 143, and is vertically moved through the support member 148. The vertical movements can be controlled, for example, by a magnetic scale using a magnetic sensor. With this configuration, the position of the second holding unit 144, and hence the distance between the reflection means 4 and the ultrasonic oscillator 3, can be set by use of the magnetic scale through operation of a handle 150 to move the support member 148 through a feed shaft having a feed screw. The position adjusting mechanism includes means for respectively effecting the vertical movements of the support member 148, the movement of the applicator 2 in the axial direction and the turning of the applicator 2 about its axis in the second holding unit 144, and the movement of the reflection means 4, the turning of the reflector about the axis of the operating rod 7 and the movements of the operating rod 7 within the hatched region in the first holding unit 142.
Further, a drive unit 157 as the movement control means 93 is disposed on the support member 148 and is adapted to axially move the arm connected to the emission means 3 in the applicator 2 in the axial direction. In the illustrated embodiment, the arm is attached to a slide portion 129 of the drive unit 157. The slide portion 129 of the drive unit 157 is driven by an electric signal supplied from a controller 5 through a cable 159. Thus, the arm, and hence the emission unit 3, can be moved in the axial direction.
The applicator 2 provided with the ultrasonic oscillator 3 is connected to the controller 5 via a cable 152. The cable 152 can be configured to includes electric wiring, and possibly also cooling liquid feed/drain tubes for injecting and draining cooling liquid into and from the region where the ultrasonic oscillator 3 is disposed inside the applicator 2. With respect to the reflection means 4, cooling liquid feed/drain tubes 153 for injecting and draining cooling liquid for the refelction means,and a signal wire extending from an output detection sensor for the reflection means are connected to the controller 5. The controller 5 includes a key operating unit, the above-mentioned control unit 91, the data base 92, and cooling liquid tanks and the like. The controller 5 is adapted to perform the control of the output of the ultrasound emitted from the ultrasonic oscillator 3, the control of the flow rates of the cooling liquid, the processing of a detection signal from the ultrasound sensor 35 at the reflector 6, the control of other functions (described later) when the other functions are provided, etc. A footswitch 154 may also be provided.
According to another aspect of the present invention, an energy treatment apparatus includes a plurality of energy emission units for emitting different-frequency energies, reflection means disposed at a position opposite to the energy emission units to reflect each of the energies emitted from the energy emission units toward a target site, and an arranging apparatus for arranging the energy emission units and the reflection means so that the different-frequency energies respectively form standing waves between the energy emission units and the reflection means, with the target site of a living body tissue being irradiated in a concentrated manner with the energies through superposition of the different-frequency standing waves. The resultant energy obtained through superposition of the plurality of standing waves forms an energy intensity distribution such that the energy intensity is greatest at the target site and decreases as the distance from the target site increases.
The energy treatment apparatus according to this embodiment comprises the plurality of energy emission units and the reflection means, with the target site being irradiated with the resultant energy of the standing waves of the plurality of different-frequency energies emitted from the plurality of energy emission units, and with the intensity of the resultant energy being maximized at the target site. Therefore, it is possible to irradiate the target site in a concentrated manner with the energies, without significantly heating living body tissues other than the target site. Thus, it is possible to heat the target site to a relatively optimum temperature for high-temperature treatment.
One version of this embodiment of the energy treatment apparatus will be described with reference to
The controller 5 comprises a control unit 91 composed of a CPU such as a microprocessor, and a data base 92 storing programs to be executed by the control unit 91 and various kinds of data. A number of control devices are connected to the control unit 91. These include an emission control means 93 for setting transmission outputs and an irradiation pattern for driving the emission unit 3 which in this embodiment is comprised of several emission units 3a, 3b, for example ultrasonic oscillators, a cooling liquid control means 94 for supplying and draining a cooling liquid to and from the applicator 2 and the reflection means 4, an arrangement control means 95 for setting the distance between and the directions of the applicator 2 and the reflection means 4, a reflection control means 96 for controlling, for example, the radius of curvature of the reflector 6 of the reflection means 4, and an energy detection means 97 for detecting the intensities of the energies, for example ultrasounds, emitted from the energy emission units 3. Further, a monitor 98, which can for example be of the cathode ray tube or liquid crystal type, is provided as a display means for displaying the results of arithmetic operations of input information, etc.
The cooling liquid control means 94 is configured to inject and drain in a circulatory fashion a cooling liquid so prevent surface layers of living body tissues other than the target site (i.e., surface layers making contact with the applicator 2 and the reflector 6) from being significantly heated by the ultrasounds emitted from the ultrasonic oscillators 3.
The energy emission unit 3 is comprised of several emission units 3a, 3b, in the disclosed embodiment two ultrasonic oscillators, for emitting different-frequency energies. The reflector 6 can be comprised of a common reflector 6 for reflecting the ultrasounds emitted from the two ultrasonic oscillators 3a, 3b. The wavelengths of the respective energies radiated from the two ultrasonic oscillators 3a, 3b are so set that an integer times one half of the wavelength of each of the respective standing waves 851, 852 are equal to the distance 1 between the emission unit 3 and the reflector 6, whereby the standing waves 851, 852 can be produced as seen in
An irradiation pattern designated by the controller 5 is such that, as shown in
The first wavelength λ851 of the standing wave 851 and the second wavelength λ852 of the standing wave 852 are determined by the following formulas. Namely, where the distance between the emission units 3 and the reflector 6 is 1, the wavelengths λ851 and λ852 are so selected as to satisfy the formulas: 1=n×λ851/2 and 1=m×λ852/2, where n and m are integers. Alternatively, where the wavelengths are present or known, the distance 1 between the main body including the emission units 3 and the reflection means 6 is controlled by the arranging apparatus 14 so that the distance 1 satisfies the above formulas, whereby the standing wave 851 and the standing wave 852 can be produced.
Where the target sites 80 are present at different positions in the depth direction, the maximum distribution of energy intensity of the third standing wave 85 synthesized from the first and second standing waves 851, 852 can be adjusted to the target site 80 by controlling the frequencies of the ultrasounds from the ultrasonic oscillators 3a, 3b.
The ultrasound as the first standing wave 851 produced by the ultrasonic oscillator 3e and the ultrasound as the second standing wave 852 produced by the ultrasonic oscillator 3f are superposed on each other at the target site 80 to strengthen each other at the target site 80. Energy treatment can thus be performed in a concentrated manner.
The controller 5 includes a control unit 91 composed of a CPU such as a microprocessor, and a data base 92 storing programs to be executed by the control unit 91 and various kinds of data. Several control devices are connected to the control unit 91. These control devices include an emission control means 93 for setting transmission outputs and an irradiation pattern for driving the emission units 3e, 3f, for example ultrasonic oscillators, a cooling liquid control means 94 for supplying and draining a cooling liquid to and from the applicator 2 and the reflectors 6b, 6c (or the emission units 3e, 3f and the reflectors 6b, 6c), an arrangement control means 95 for setting the distance between and the directions of the applicator 2 and the reflection means 4, a reflection control means 96 for controlling, for example, the radii of curvature of the reflectors 6b, 6c, and an energy detection means 97 for detecting the intensities of the energies, for example ultrasounds, emitted from the energy emission units 3e, 3f. Further, a monitor 98, which can be of the cathode ray tube or liquid crystal type for example, is provided as a display means for displaying the results of arithmetic operations of input information, etc.
The cooling liquid control means 94 is configured for injecting and draining in a circulatory manner for example a cooling liquid so as to prevent surface layers of the living body tissues other than the target site (i.e., surface layers making contact with the applicator 2 and the reflectors 6b, 6c) from being significantly heated by the ultrasounds emitted from the ultrasonic oscillators 3e, 3f.
In connection with the various embodiments of the applicator described above, an observation means for observing living body tissues may be provided in the distal end of the applicator 2. The observation means can be, for example, an endoscope, a CCD camera or the like. As mentioned above, where an endoscope is provided, the applicator 2 is inserted into the urethra, and the urethra is then observed through use of the endoscope to observe, for example, the shape characteristics of the urethra at the prostate and to judge the forward-backward position of the target site 80. An example of an endoscope will be described below.
An endoscope uses an optical fiber functioning also for radiating an illumination beam, and is provided with an imaging lens at the distal end thereof. The endoscope can be disposed so that it can be freely inserted and retracted through a proximal end portion of the energy irradiation apparatus. Using the endoscope observation, the ultrasound emission unit 3 can be positioned as desired. In addition, through use of an endoscope provided with a guide beam function, the ultrasound irradiation position can be visually confirmed. Further, since the irradiated surface can be continuously observed during irradiation with ultrasound, the irradiation conditions can be optimized while observing the irradiated state.
The applicator 2 and the reflection means 4 are disposed to be movable so that the distance between them can be controlled by the arranging apparatus 14. Therefore, the applicator 2 and the reflection means 4 are preferably formed of materials comparatively high in hardness, and can be formed, for example, of stainless steel or the like. Possible material for constituting the applicator 2 will be described later. The applicator 2 is provided with a window (not shown) for radiating the energy emitted from the emission unit 3. The window can be used also for observation by use of the observation means which will be described later and is an endoscope in this embodiment. It is desirable to utilize a material for the window that is excellent in transmission characteristics. Examples of such materials include polyethylene terephthalate, quartz glass, acrylic resin, polystyrene, polycarbonate, polyethylene, polypropylene, polyvinylidene chloride, Teflon®, and polyester.
Also, a balloon capable of expansion and contraction for position fixation after insertion may be provided at that portion of the applicator 2 which is inserted in a living body cavity. It is preferable to use a material excellent in transmissivity to ultrasound as the material for constituting the balloon. Examples of such material include polyolefin, polyester, polyamide, latex, and cellulose. This helps ensures that energy loss or heat generation due to absorption of ultrasound by the balloon is suppressed.
As a working fluid for expanding the balloon, air and a cooling liquid can be used. The working fluid is not particularly limited as long as it enables expansion and contraction of the balloon. A cooling liquid is preferred. With cooling liquid used as the working fluid, surface layer portions of the body tissues can be cooled by the cooling liquid at the time of irradiation with ultrasound, whereby the surface layer portions can be more securely prevented from being damaged.
The temperature of the cooling liquid is not particularly limited inasmuch as the cooling liquid can cool the surface layer portions of the living body tissues, but is preferably 0° C. to 37° C., more preferably about 0° C. to 25° C.
Physiological saline, Ringer's solution and the like are preferably used as the working fluid. With one of these liquids used as the working fluid, it is possible to reduce the influence of leakage of the working fluid into the inside of a living body which might occur due to some cause.
Where the cooling liquid is used as the working fluid, it is preferable to circulate the cooling liquid,, It is also preferably to circulate the cooling liquid from before the irradiation with ultrasound begins until the ultrasound irradiation is finished and the treatment is over. With the cooling liquid circulated, cooling efficiency can be enhanced, and, with the cooling liquid circulated from before the start of ultrasound irradiation until the ultrasound irradiation is finished, the surface layer portions can be further cooled.
It is preferable to provide the drain portion with, for example, a pressure valve which is opened when a predetermined pressure is exceeded. This makes it possible to expand the balloon at a predetermined pressure, irrespective of the flow rate of the cooling liquid.
It is also preferable to control the temperature of the cooling liquid and the flow rate of the cooling liquid in conjunction with the irradiation with ultrasound. This makes it possible to prevent the surface layer portions from being cooled or heated excessively.
The balloon can be provided with a temperature sensor for detecting the surface temperature of the body tissue. In this case, it is possible to detect the surface temperature of the body tissue by way of the temperature sensor, and to utilize the thus obtained information (detected value) to control cooling. This helps contribute to an efficient, necessary and sufficient cooling.
The balloon may be formed to surround the whole circumference of the housing, exclusive of the ultrasound emission area. In this case, expanding the balloon presses the ultrasound emission area of the main body against the body cavity wall so that the distance between the target of irradiation and the emission unit is made stable, leading to relatively good stability at the time of irradiation.
A hard pipe made of, for example, a metal such as stainless steel is preferably used as the material for constituting the applicator 2. Examples of the material for constituting the main body of the applicator include polyolefins such as polyethylene, polypropylene, etc.; ethylene-vinyl acetate copolymer (EVA); polyvinyl chloride; polyesters such as polyethylene terephthalate, polybutylene terephthalate, etc.; polyamide; polyurethane; polystyrene; polycarbonate; fluororesin; polymer alloys containing one of these materials, and combinations of two or more of these materials.
In addition, the surface of the main body may be provided with a lubricating coating formed of a hydrophilic polymer material, silicone, fluororesin or the like. This reduces friction on the main body surface, and allows for a smoother insertion of the applicator 2 into a body cavity.
Preferable examples of the hydrophilic polymer material to be used for the lubricating coating include carboxymethyl cellulose, polysaccharide, polyvinyl alcohol, polyethylene oxide, poly(sodium acrylate), methyl vinyl ether-maleic anhydride copolymer, and water-soluble polyamide. Among these, methyl vinyl ether-maleic anhydride copolymer is particularly preferred.
In the case of using the energy treatment apparatus with the main body coated with the hydrophilic polymer material, the surface layer of the energy treatment apparatus is immersed, for example, in physiological saline or the like. This wets the surface layer, giving lubricity to the surface of the energy treatment apparatus. Since the energy treatment apparatus has the surface layer containing the hydrophilic polymer material, friction between the living body tissues and the energy treatment apparatus is reduced, whereby the burden on the patient is alleviated, and safety is enhanced. For example, it is possible to smoothly perform the insertion of the energy treatment apparatus into a body cavity, the pulling of the energy treatment apparatus out of the body cavity, and the movement and rotation of the energy treatment apparatus in the body cavity.
With the energy treatment apparatus 1 as above-described, the target site 80 is irradiated with both the ultrasound from the ultrasonic oscillator 3 and the reflected ultrasound from the reflector 6 in a synchronous manner so that both ultrasounds (the reflected ultrasound from one emission and the ultrasound from the next emission) are superposed on each other at the target site 80, thus enhancing the efficiency of accumulation of ultrasound into or at the target site 80 together with the ultrasound utilization efficiency, and to heat the target site to a relatively optimum temperature for high-temperature treatment.
The use of the depth-reaching ultrasound as the irradiation energy makes it possible to apply a high-temperature treatment to a site located at a depth.
Also, with the ultrasound emission unit 3 repeatedly reciprocated in the axial direction by the electric drive means 157, only the target site 80 can be irradiated in a concentrated manner with the ultrasound, without giving significant damage to the normal living tissues in the surroundings. In addition, the ultrasound accumulation efficiency can be increased so that a heating temperature appropriate for the target site can be attained even where the ultrasound emission output is reduced.
Where the drive means 157, for example, constituting the moving means for moving the ultrasound emission unit 3 is provided with an adjusting means for adjusting the moving amount of the reciprocating movement of the emission unit 3, an ultrasound treatment from a relatively optimum position can be achieved at the time of irradiation with ultrasound.
Since the applicator 2 and the reflection means 4 can be moved, by the arranging apparatus 14, in the longitudinal direction of the applicator 2 and/or in a direction orthogonal to the longitudinal direction according to the target site 80, the ultrasound radiated from the ultrasonic oscillator 3 can be set to a relatively optimum position for the target site 80. Also, it is possible to perform positioning while observing.
The description set forth above describes embodiments of the energy treatment apparatus in which two standing waves are radiated from two ultrasound emission units to strengthen each other on an energy basis. It is to be understood that three or more standing waves may be adopted, whereby the accumulation of energies at the target site can be enhanced further. The wavelengths of the respective standing waves are set so that the distance 1 between the emission unit and the reflector is an integer times of one-half of the wavelength of each of the standing waves. Also, with the energy treatment apparatus 1 according to embodiment as described above, the target site 80 is irradiated with both the respective different-frequency ultrasounds from the plurality of ultrasonic oscillators and the respective reflected ultrasounds from the reflectors so that both the emitted ultrasounds and the reflected ultrasounds are superposed on each other at the target site 80 to produce the plurality of different-frequency standing waves from which a standing wave is synthesized. It is thus possible to enhance the efficiency of accumulation of ultrasounds into the target site 80 together with the ultrasound utilization efficiency, and to heat the target site to a relatively optimum temperature for high-temperature treatment.
The controller 5 controls the energy emission unit 3 and the reflection means 4, so that the treatment can be performed more efficiently and speedily. Since the arranging apparatus 14 can arrange the energy emission unit 3 and the reflection means 4, it is possible to stabilize the positions of the energy emission unit 3 and the reflection means 4 relative to the target site, and to irradiate the target site accurately at the time of irradiation with the energy.
By providing the cooling means for the applicator 2, it is possible to cool the surface layer portions of the living body tissues with the cooling liquid, and to more readily prevent the surface layer portions from being damaged.
Using the acoustic lens 23 for converging, collimating, or diverging the ultrasound provided at the ultrasound emission surface of the ultrasonic oscillator 3, it is possible to irradiate the target site with the ultrasound in a wider region or a narrower region or in the manner of concentrating the ultrasound, depending on the state of the target site.
The cooling means provided for the reflection means 4 makes it possible to cool the surface layer portions of living body tissues with the cooling liquid, and to prevent more securely the surface layer portions from being damaged.
Providing the reflection means 4 with the fixed reflective surface or the variable reflective surface, it is possible to use an optimum reflective surface according to the treatment range of the target site to thus achieve a more efficient treatment.
Since the arranging apparatus 14 can be provided with a changing function for changing the radiation direction of ultrasound from the ultrasonic oscillator 3, the ultrasonic oscillator 3 can be changed to an appropriate position relative to the target site, thus shortening the setting time.
With the curvature of the reflective surface of the reflection means 6 made variable, the irradiation range can be varied according to the position in the depth direction of the target site and the area of the target site.
By providing the reflector 6 with the ultrasound sensor 35, it is possible to detect the output intensity of the ultrasound, to control the output of the ultrasound emitted from the ultrasonic oscillator 3, and to reconsider the settings of conditions.
In the energy treatment apparatus disclosed here, in arrangements in which the reflector 6 is provided with an air bleeding hole 36 and an ultrasound jelly injection hole 37, injecting an ultrasound jelly into the reflector 6 makes it possible to bring the reflector 6 into close contact with a body cavity wall. This allows the ultrasound to be more accurately reflected toward the target site 80 without significant irregular reflection of the ultrasound.
Providing the arranging apparatus 14 for holding the main body and the reflector 6, the main body and the reflector 6 can be fixed at relatively optimum positions, and so energy irradiation can be performed relatively stably.
By making it possible to produce an irradiation pattern for concentrating the energy into or at the target site designated by the controller 5, relatively efficient treatment of the target site is possible.
As described above, the controller 5 can control the cooling means for the main body and the cooling means for the reflection means. This allows the surface layer portions of living body tissues to generally always be cooled with the cooling liquid. This thus more reliably inhibits or prevents the surface layer portions from being damaged and so a relatively speedy and efficient treatment can be achieved.
Also, since the controller 5 controls the reflection means 4, by varying the curvature of the fixed reflective surface or variable reflective surface, it is possible to adjust the irradiation range to an irradiation range according to the position in the depth direction of the target site and the area of the target site, and to achieve a relatively speedy and efficient treatment.
When an endoscope is arranged in the applicator 2, it is possible to observe the state of the target site before and after a treatment, and generally optimize the irradiation conditions while observing the state.
When the applicator 2, and possibly also the reflection means 4, is provided with the balloon capable of expansion and contraction, the applicator 2 for example can be pressed against a body cavity wall in the vicinity of the target site 80. The distance between the target site 80 and the ultrasonic oscillator 3 can thus be made more stable, and the irradiation of the target site 80 with the ultrasound can be better stabilized.
Applying a surface layer including a hydrophilic polymer material on the surface of the applicator 2, and possibly also the reflector means 4, makes it possible to reduce the friction, for example the friction on the surface of the applicator 2. Thus, in the case of the applicator, it is possible to more smoothly insert the applicator 2 into a body cavity, pull the applicator 2 out of the body cavity, and move and rotate the applicator 2 inside the body cavity.
As described above, the main body, the reflection means, and the balloon can be provided respectively with cooling means. However, the cooling means for the main body, the reflection means and the balloon can be provided in any combination desired, according to the cooling conditions.
The embodiments described above have been described in the context that the energy radiated toward the living body tissue is ultrasound. However, the present invention is not limited to these examples, and the invention is applicable also to irradiation with other energies, for example laser beams, electromagnetic waves having directivity, and others. In such situations, if necessary, the applicator can be provided in its area corresponding to the emission unit with a window for ensuring that irradiation with the energy is not hindered.
While the examples described above have been discussed in the context that the living body tissue which is the object of high-temperature treatment is the prostate, the present invention is not limited in this regard. The object of treatment includes all living body tissues that can be subjected to high-temperature treatment by irradiating them with an energy from the inside of a living body, i.e., from a blood vessel, a digestive tract (esophagus, intestines, etc.), abdominal cavity, or the like, or from the body surface.
Since the embodiments of the energy treatment apparatus described here include the energy emission unit(s) and the reflection means, the energy utilization efficiency is enhanced. It is thus possible to enhance the accumulation of energy into or at the target site and, hence, the intensity of the energy, while also generally suppressing the emission output. Therefore, it is possible to heat the target site to a temperature relatively optimum for high-temperature treatment, and to perform an efficient high-temperature treatment while using a relatively low output. In addition, the energy treatment apparatus can be configured, as described by way of example above, so that the energy emitted from the emission unit(s) is collected into the target site by way of different routes, thus increasing the efficiency of accumulation of energy into the target site. Therefore, it is possible to heat the target site to a temperature relatively optimum for high-temperature treatment, and to perform thermotherapy in a relatively short time.
Since the energy treatment apparatus includes the energy emission unit(s) and the reflection means, the energy utilization efficiency is enhanced, and it is possible to enhance the accumulation of energy into the target site and, hence, the intensity of the energy, while suppressing the emission output. Also, the energy emission unit(s) is capable of being moved and so the target site can be irradiated with the energy coming through different paths. Since the target site is irradiated with energy while moving the energy emission unit(s), the efficiency of accumulation of the energy into the target site can be further enhanced, without exerting any significant influence on the living body tissues other than the target site.
Where the energy treatment apparatus utilizes an elongate main body having the energy emission unit(s) and a moving means by which the position of the energy emission unit(s) disposed in the main body is moved in the axial direction of the main body, the energy can be efficiently accumulated into the target site while suppressing the heating of body tissues other than the target site. Also, when the energy treatment apparatus includes the moving means by which the position of the energy emission unit disposed in the main body is repeatedly reciprocated in the axial direction of the main body, only the target site is irradiated in a concentrated manner with the energy, without significantly damaging the normal living tissues surrounding the target site. It is thus possible to enhance the energy accumulation efficiency so as to attain an appropriate heating temperature for the target site, even where the energy emission output is set relatively low.
By providing a moving means for the energy emission unit(s) to generally ensure that the energy emitted from each moved position of the energy emission unit(s) is concentrated into or at the target site, the efficiency of accumulation of the energy into the target site can be enhanced. Also, where the moving means is provided with a movement control means by which the movement amount and moving speed of the reciprocating movement of the energy emission unit(s) can be regulated, it is possible to achieve an energy treatment by irradiation with the energy from a relatively optimum position.
Also, the emission control means provided for controlling the emission of the energy emitted from the energy emission unit(s) allows the emission pattern of the energy to be controlled. The energy can thus be efficiently accumulated into or at the target site.
Embodiments of the energy treatment apparatus include a plurality of energy emission units for emitting energies of different-frequency standing waves and reflection means, with the target site being irradiated with energy obtained by superposing the different-frequency standing waves on each other. The energy utilization efficiency is thus enhanced, and it is possible to enhance the accumulation of energy into the target site and hence the intensity of the energy, while also suppressing the emission output. It is thus possible to heat the target site to a temperature for high-temperature treatment and to perform an efficient high-temperature treatment while using a relatively low output.
It is also possible to ensure that the energy obtained through superposition of the standing waves by controlling the energy emission patterns and the distance between the emission units and the reflection means provides an energy intensity distribution such that the energy intensity is relatively high at the target site. At the same time, energies can be efficiently accumulated at or into the target site.
By superposing the energies which partly penetrate through the target site and are reflected by the reflection means on the energies from the energy emission units to produce different-frequency standing waves and by irradiating the target site with the different-frequency standing waves in a further superposed manner, the energy accumulation is enhanced and the target site can be heated to a relatively optimum temperature.
Additionally, irradiating the target site with the energies of different-frequency standing waves from the plurality of energy emission units makes it possible to superpose the energies of the standing waves on each other in generally optimum conditions according to each of target sites which may differ in depth, thus enhancing the accumulation of energies heating the target site to an optimum temperature.
In embodiments of the energy treatment apparatus described above, a plurality of energy emission units are arranged on one side, and reflection means is arranged at a position opposite to the plurality of energy emission units with the target site therebetween. Therefore, energy utilization efficiency is enhanced. In addition, it is possible to enhance the accumulation of energies into the target site and, hence, the energy intensity, while suppressing the emission outputs. The target site can thus be heated to a temperature sufficient for high-temperature treatment, and relatively efficient high-temperature treatment can be achieved using relatively low outputs.
Embodiments of the energy treatment apparatus described above utilize energy emission units which each integrally include reflection means and which are arranged at opposite positions with the target site therebetween. This also allows enhancement of energy utilization-efficiency, and makes it possible to enhance the accumulation of energies into or at the target site and hence the energy intensity, while suppressing the emission outputs. The target site can thus be heated to a temperature for high-temperature treatment, and efficient high-temperature treatment can be performed while using relatively low outputs.
Irradiating the target site with the energy from the energy emission unit(s) makes it possible to ensure that a part of the energy penetrates through the target site and is reflected by the reflection means and that the reflected energy and the next energy are superposed on each other at the target site, to enhance the accumulation of energy, and to heat the target site to an optimum temperature. Also, by irradiating the target site with both the energy partly penetrating through the target site and reflected by the reflection means and the next energy pulse from the energy emission unit(s) in such a manner that both energies are superposed on each other at the target site, the energy accumulation is enhanced and the target site can be heated to a desired or relatively optimum temperature.
The arranging apparatus can arrange both a main body including the energy emission unit(s) and the reflection means. Thus, the positions of the main body and the reflection means relative to the target site can be stabilized, and the target site can be accurately irradiated with the energy at the time of irradiation with the energy.
Providing the arranging apparatus with a holding unit for the main body including the energy emission unit(s), a holding unit for the reflection means, and a mechanism for adjusting the relative positions of the energy emission unit(s) and the reflection means makes it possible to fix the energy emission unit(s) and the reflection means at desired or relatively optimum positions to facilitate generally stable irradiation with the energy. Also, with an arrangement control means provided for controlling the arranging apparatus, irradiation with energy can be efficiently performed in a relatively optimum layout.
Since the arrangement control means performs a control allowing the emitted energy from the energy emission unit(s) and the reflected energy from the reflection means to be superposed on each other at the target site, it is possible to perform treatment more efficiently and speedily. Also, since the arranging apparatus is capable of changing the direction of the energy emission unit(s), the position of the emission unit(s) can be changed to an appropriate direction relative to the target site, and the setting time can be shortened.
When the emission of the energy from the energy emission unit(s) is controlled by the emission control means in conjunction with the energy reflected by the reflection means, it is possible to superpose the emitted energy and the reflected energy at the target site, and thereby efficiently accumulate the energy. Also, because the emission control means controls the irradiation pattern for concentrating the emitted energy into the target site, the irradiation output, and the irradiation time, it is possible to treat the target site optimally, efficiently, and speedily. Further, because the emission control means controls the irradiation pattern to intermittently irradiate the target site with the emitted energy from the emission unit(s), it is possible to perform a speedy and efficient treatment. Further, because the emission control means controls the irradiation pattern so that the energy intermittently emitted from the energy emission unit(s) and the reflected energy reflected by the reflection means will reach the target site simultaneously, it is possible to achieve a speedy and efficient treatment.
With the reflection means provided with a fixed reflective surface or a variable reflective surface, an optimum reflective surface can be used and a more efficient treatment can be performed, according to the range of treatment of the target site. Also, with the reflection means formed so that the radius of curvature of its reflective surface is variable, the irradiation range can be varied according to the position in the depth direction of the target site and the area of the target site. By providing the reflection control means for controlling the reflection means, it is possible to perform the treatment more efficiently and speedily. Also, providing the reflection means with an energy detection means for detecting the reaching efficiency of energy, the emitted energy can be detected, making it possible to control the output of the emitted energy and to possibly reconsider the settings of the irradiation conditions. Where the reflector is provided with an air bleed hole, it is possible to bleed air and to bring the reflector into close contact with a body cavity wall. The energy radiated from the emission unit(s) can thus be reflected accurately toward the target site, without significant irregular reflection.
With a cooling means provided at the energy emission unit(s) or at a main body including the energy emission unit(s), surface layer portions of living body tissues can be cooled with a cooling liquid, and the surface layer portions can be inhibited or prevented from being damaged. Also, with a cooling means provided for the reflection means, the temperature of living body tissues in the vicinity of the reflection means can be prevented from being raised, and the treatment of the target site can be performed efficiently and stably. In addition, by providing cooling control means for controlling the cooling means, surface layer portions of body tissues can be cooled with cooling liquid to prevent damage to the surface layer portions and allow a relatively speedy and efficient treatment to be performed. It is also possible to reduce the possibility that the temperature of the living body tissues in the periphery of the reflection means will be excessively raised, thus allowing the treatment of the target site to be relatively efficiently and stably performed.
The controller provided for controlling the movement control means allows a relatively speedy and efficient treatment to be realized through automation. Also, with a controller provided for controlling the arrangement control means or controlling both the arrangement control means and the movement control means, it is possible to relatively optimally set the positions of the emission unit and the reflection means relative to the target site, and to perform an efficient and speedy treatment through automation. Providing a controller for controlling the arrangement control means or for controlling both the arrangement control means and the emission control means makes it possible to achieve an efficient and speedy treatment through automation of the relevant function(s). Additionally, with a controller provided for controlling the reflection control means or controlling at least two of the reflection control means, the arrangement control means, and the emission control means, an efficient and speedy treatment can be performed through automation of the relevant function(s). Also, by providing a controller for controlling the cooling control means or controlling at least two of the cooling control means, the arrangement control means, the emission control means, and the reflection control means, an efficient and speedy treatment can be achieved through automation of the relevant function(s).
By providing a controller for controlling the emission control means or controlling at least two of the emission control means, the arrangement control means, and the movement control means, a relatively efficient and speedy treatment can also be achieved through automation of the relevant function(s). A similar result can be achieved with a controller provided for controlling the reflection control means or controlling at least two of the reflection control means, the emission control means, the arrangement control means, and the movement control means. A relatively efficient and speedy treatment can also be performed through automation of the relevant function(s) by providing a controller for controlling the reflection control means or controlling at least two of the reflection control means, the emission control means, the arrangement control means, and the movement control means, Additionally, with a controller provided for controlling the cooling control means or controlling at least two of the cooling control means, the reflection control means, the emission control means, the arrangement control means, and the movement control means, a relatively efficient and speedy treatment can be achieved through automation of the relevant function(s).
Where a main body including the energy emission unit(s) is provided with means for converging, collimating, or diverging the spreading angle of the emitted energy, it is possible to radiate the energy to a wider area or a narrower area and to irradiate the target site in a concentrated manner with the ultrasound, depending on the state of the target site. Where a main body including the energy emission unit(s)is provided with observation means, the state of the target site before and after the treatment can be observed, and the irradiation conditions can be relatively optimized while observing the state.
Where the energy radiated from the emission unit(s) is ultrasound, a site located in the depth can be selectively irradiated with ultrasound.
The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments described. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the invention be embraced thereby.
Number | Date | Country | Kind |
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2003-197370 | Jul 2003 | JP | national |
2003-202544 | Jul 2003 | JP | national |
2003-205115 | Jul 2003 | JP | national |