Abstract:
There is provided an ultrasonic therapeutic apparatus, which is capable of shortening a surgery time even in a case of resecting and stopping bleeding of a plurality of sites. 
     The ultrasonic therapeutic apparatus includes a probe which is interpolated into a sheath, and a treatment section which is connected to or formed integrally with a front-end portion of the probe, and which his exposed to an exterior of the sheath, and a diseased part is resected or coagulated by making propagate ultrasonic waves to the treatment portion via the probe, and the ultrasonic therapeutic apparatus further includes a mechanism which cools down the treatment portion by carrying out heat exchange by the probe and a coolant gas which has been discharged into the sheath.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an ultrasonic therapeutic apparatus. 
       BACKGROUND ART 
       [0002]      FIG. 6  shows an overall arrangement of an ultrasonic cutting and coagulating system  10  which has hitherto been used. In the ultrasonic cutting and coagulating system  10 , vibration of an ultrasonic transducer, upon being amplified by a horn, is transmitted to a fixed blade  34  which formed at a front end of a probe, via the probe (vibration transmission rod) connected to the horn. A movable blade  42  is pivotably retractable with respect to the fixed blade  34  via an operating rod. The probe and the operating rod are accommodated in a sheath  55 , and are supported inside the sheath  55  by supporting members which are disposed at a predetermined distance inside the sheath  55 . It is possible to resect while cauterizing a tissue sandwiched between the fixed blade  34  and the movable  42  by frictional heat due to ultrasonic waves, and also possible to stop bleeding simultaneously. 
       CITATION LIST 
     Patent Literature 
       [0000]    
       
         Patent Document 1: Japanese Patent Application Laid-open Publication No. 2002-186627 
       
     
       SUMMARY OF INVENTION 
     Technical Problem 
       [0004]    Generally, in one surgery, resection or coagulation of a plurality of locations becomes necessary. Here, in a structure described in Patent Document 1, after the treatment, the fixed blade  34  and a surrounding site thereof are at a high temperature. Therefore, there is a possibility of an injury caused due to a high-temperature part of a treatment tool making a contact with a site other than a diseased part. For preventing an injury caused due to such high-temperature site, it is necessary to wait till the temperature of the fixed blade  34  comes down, and it is not possible to carry out the subsequent treatment. Therefore, there has been a problem of a time for surgery becoming long. 
         [0005]    Accordingly, installing of a cooling mechanism which has a small-size and an improved performance, to be incorporated in the treatment tool has been sought. During the treatment, the fixed blade is required to attain high temperature in a short time for exerting an effect of resecting and stopping bleeding. The cooling mechanism is sought to be being capable of cooling down the fixed blade  34  in short time after the end of treatment, with a quick response, without hindering the rise in temperature of the fixed blade by ultrasonic waves, by stopping functioning during the treatment. 
         [0006]    The present invention has been made in view of the abovementioned issues, and an object of the present invention is to provide an ultrasonic therapeutic apparatus which is capable of shortening a surgery time even in a case of resecting and stopping bleeding of the plurality of parts. 
       Solution to Problem 
       [0007]    To solve the abovementioned issues and to achieve the object, an ultrasonic therapeutic apparatus according to the present invention includes 
         [0008]    a probe which is interpolated into a sheath, and 
         [0009]    a treatment section which is connected to or formed integrally with a front-end portion of the probe, and which is exposed to an exterior of the sheath, and 
         [0010]    a diseased part is resected or coagulated by making propagate ultrasonic waves to the treatment section via the probe, and 
         [0011]    the ultrasonic therapeutic apparatus further includes, 
         [0012]    a mechanism which cools down the treatment section by carrying out heat exchange by the probe and a coolant gas which has been discharged into the sheath. 
         [0013]    Moreover, according to a preferable aspect of the present invention, it is desirable that the coolant gas is supplied by infusing a high-pressure gas through an infusion tube having a thin diameter which is disposed inside the sheath, and furthermore, by cooling down the high-pressure gas at a front-end portion of the infusion tube. 
         [0014]    Furthermore, according to a preferable aspect of the present invention, it is desirable that the infusion tube is interpolated into a reflux tube which is disposed inside the sheath, and the coolant gas which has been discharged from the infusion tube flows into the reflux tube and is discharged to the exterior of the sheath, and heat exchange is carried out between the high-pressure gas which is infused into the infusion tube and the coolant gas which is discharged from the reflux tube. 
         [0015]    According to a preferable aspect of the present invention, it is desirable that the infusion tube is detachable from the reflux tube. 
         [0016]    Moreover, according to a preferable aspect of the present invention, it is desirable that the reflux tube is detachable from the sheath. 
         [0017]    Furthermore, according to a preferable aspect of the present invention, it is desirable that the infusion tube includes an infusion portion through which the high-pressure gas is to be infused, and a depressurizing portion having a diameter thinner than the diameter of the infusion portion which is formed at the front-end portion. 
       Advantageous Effects of Invention 
       [0018]    The ultrasonic therapeutic apparatus according to the present invention has a Joule-Thomson cooler having a thin double-tube structure incorporated inside a sheath which forms a treatment tool. A front end of a probe is to be cooled down from inside of the sheath, and it is possible to cool down by heat transfer by conduction between the front end of the probe and the treatment tool. Accordingly, the ultrasonic therapeutic apparatus according to the present invention shows an effect that it is possible to shorten a surgery time even in a case of resecting and stopping bleeding of a plurality of sites. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0019]      FIG. 1  is a diagram showing a structure of a treatment tool according to an embodiment of the present invention; 
           [0020]      FIG. 2  is a diagram showing a structure of a JT cooler in the embodiment; 
           [0021]      FIG. 3  is a diagram showing a state in which the JT cooler in the embodiment is divided into a reflux tube and an infusion tube; 
           [0022]      FIG. 4  is a diagram for explaining an operation of resecting, stopping bleeding, and cooling down a diseased part by letting ultrasonic waves to be propagated to a treatment section in the embodiment; 
           [0023]      FIG. 5  is an explanatory diagram of an operation of the JT cooler in the embodiment; and 
           [0024]      FIG. 6  is a diagram showing an overall arrangement of a conventional ultrasonic cutting and coagulating system. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0025]    An embodiment of an ultrasonic therapeutic apparatus according to the present invention will be described below in detail by referring to the accompanying diagrams. However, the present invention is not restricted to the embodiment described below. 
         [0026]    The ultrasonic therapeutic apparatus according to the present invention will be described by referring to diagrams from  FIG. 1  to  FIG. 5 .  FIG. 1  is a diagram showing a treatment tool of the ultrasonic therapeutic apparatus according to the present invention. Here, for simplifying the description, a characteristic structure of the embodiment is described below. Practically, the structure also includes a movable blade and a movable mechanism and a transducer which is connected to a rear end of a probe (not shown in the diagram). 
         [0027]    A treatment tool  101  has a structure in which, a probe  103  is interpolated into a sheath  102 , and a JT (Joule-Thomson) cooler  104  for cooling down the probe  103  is incorporated into a gap between the sheath  102  and the probe  103 . A positional relationship of the sheath  102 , the probe  103 , and the JT cooler  104  is regulated by supporting members  106 . Moreover, a treatment portion  105  which is formed integrally with a front end of the probe  103  is protruded from the sheath  102  and exposed to an exterior. A structure of the JT cooler  104  (will be described later) is a structure in which, a part thereof is protruded from the sheath  102  as shown in  FIG. 1 . An interior of the sheath  102  is divided into a plurality of sites by the supporting members  106 , and the sites of the sheath  102  have a mutually air-tight structure to certain extent. 
         [0028]      FIG. 2  shows a structure of the JT cooler  104 . The JT cooler  104  has a structure in which, an infusion tube  111  is interpolated into a reflux tube  110 . The infusion tube  111  is connected to a gas cylinder (will be described later, refer to  FIG. 5 ). The infusion tube  111  is formed of three portions namely, a rear-end portion of the reflux tube  110 , or in other words, a rear-end side infusion portion  111   a  which is protruded from a portion toward an operator, an infusion-tube front-end side infusion portion  111   b  which is to be interpolated into the reflux tube  110 , and a front-end side of the front-end side infusion portion  111   b , or in other words, a depressurizing portion  111   c  which is fitted on a side of the treatment tool. 
         [0029]    Moreover, an inner diameter of the depressurizing portion  111   c  is smaller than an inner diameter of the rear-end side infusion portion  111   a  and an inner diameter of a front-end side infusion portion  111   b . The reflux tube  110  and the infusion tube  111  are connected by a tube connector  112  and are detachable. Moreover, a gas discharge hole  113  is formed at a site near the tube connector  112  of the reflux tube  110 . 
         [0030]    Both a front end with the reflux tube  110  and a front end of the depressurizing portion  111   c  of the infusion tube are open. From among the plurality of sites inside the sheath  102  shown in  FIG. 1  which are partitioned by the supporting members  106 , both are positioned at a front-end side of the probe  103 , or in other words, positioned near the treatment portion side. 
         [0031]      FIG. 3  shows a state in which the JT cooler  104  is divided into the reflux tube  110  and the infusion tube  111 . The infusion tube  111  is flexible, and can be inserted into the reflux tube  110 , and connected by the tube connector  112 . 
         [0032]      FIG. 4  is a diagram showing a schematic structure for explaining an operation of resecting, stopping bleeding, and cooling down a diseased part by letting ultrasonic waves to be propagated to the treatment portion  105 . Ultrasonic vibration which is generated in a BLT  115  (Bolt-clamped Langevin-type Transducer) is amplified by passing through a horn  114 , and makes vibrate the probe  103  and the treatment portion  105 . The JT cooler  104  cools down the probe  103  and the front-end portion by discharging CO 2  gas. An operation of the JT cooler  104  will be described later. 
         [0033]    Treatment of resecting and stopping bleeding is carried out by vibration of the treatment portion  105 . Treatment of resecting and stopping bleeding of the diseased part and cooling down of the probe  103  are controlled by opening and closing of a solenoid valve  108  of a CO 2  gas cylinder  109  and a driving power source  117  of the BLT  115 . The abovementioned control is carried out by a system controller  119 . After the operator has completed the treatment, by the control of the system controller  119 , it is possible to realize lowering of temperature of the probe  103  and eventually lowering of temperature of the treatment portion  105  in a short time by opening the solenoid valve  108  of the CO 2  gas cylinder  109  for a predetermined amount of time. 
         [0034]      FIG. 5  is a diagram showing a schematic structure for explaining the operation of the JT cooler  104 . The high-pressure CO 2  gas which has been infused into the infusion tube  111  causes a sudden pressure drop by passing through the depressurizing portion  111   c  having a small inner diameter. Accordingly, a drop in temperature of the gas occurs due to Joule-Thomson effect. The CO 2  gas which has been cooled down is discharged from the front end of the depressurizing portion  111   c  and carries out heat exchange with the probe  103 , and lowers the temperature of the probe  103 . 
         [0035]    Furthermore, the CO 2  gas which has been cooled down is discharged from the front end of the depressurizing portion  111   c  and flows into the reflux tube  110 . At this time, by lowering the temperature of the probe  103 , the temperature of the treatment portion  105  is also lowered due to heat transfer by conduction. Here, it is preferable to set the inner diameter and a length of the depressurizing portion  111   c  such that a pressure of the gas in a state of being discharged from the depressurizing portion  111   c  becomes slightly higher than 1 atm. Accordingly, it is possible to let the temperature drop due to the Joule-Thomson effect to be the maximum. At the same time, since the purpose is served even when a pressure resistance of the sheath  102  which has been partitioned by the supporting member  106  is not high, it is advantageous from a point of small-sizing and cost. 
         [0036]    The cooled-down CO 2  gas which has flowed into the reflux tube  110  retains a low temperature to certain extent. The cooled-down CO 2  gas carries out heat exchange with the CO 2  gas which is infused into the front-end side infusion portion  111   b  of the infusion tube  111  inside the reflux tube  110 . Accordingly, the CO 2  gas which is infused is cooled down at a point of time of reaching the depressurizing portion  111   c . In other words, for the CO 2  gas which is discharged from the depressurizing portion  111   c , in addition to the temperature drop due to the Joule-Thomson effect in the depressurizing portion  111   c , it is possible to achieve an effect of further temperature drop. Therefore, it is possible to lower the temperature of the CO 2  gas which is discharged, close to a liquefaction temperature of the CO 2  gas by optimizing the design. The CO 2  gas which flows into the reflux tube  110  is eventually discharged through a gas discharge hole  113  in the reflux tube  110  provided at an exterior of the sheath  102 . 
         [0037]    In  FIG. 5 , the gas discharge hole  113  is drawn to be open toward a rightward horizontal direction with respect to a paper surface so that a route shown by arrows for gas discharge is easily understandable. The gas discharge hole  113 , without being restricted to the abovementioned type, can also be let to open in a direction toward a front surface with respect to the paper surface as shown in  FIG. 2 ,  FIG. 3 , and  FIG. 4 . 
         [0038]    In the embodiment described above, the Joule-Thomson cooler having a thin double-tube structure is incorporated inside the sheath which forms the treatment tool. The front end of the probe is to be cooled down from inside of the sheath, and it is possible to cool down by heat transfer by conduction between the front end of the probe and the treatment tool exposed to an exterior of the sheath which is connected to or formed integrally with the front-end portion of the probe. Accordingly, an effect is shown that the temperature of the front end of the probe by which, treatment of plurality of sites is carried out, is lowered in a short time, and also, even by stopping the cooler during the treatment, there is almost no increase in the treatment time. 
         [0039]    The present invention may have various modified embodiments without departing from the scope of the invention. 
       INDUSTRIAL APPLICABILITY 
       [0040]    As it has been described above, the ultrasonic therapeutic apparatus according to the present invention being capable of cooling a treatment portion in a short time is useful for carrying out a treatment of resecting and stopping bleeding of the plurality of sites. 
       REFERENCE SIGNS LIST 
       [0000]    
       
         
           
               101  treatment tool 
               102  sheath 
               103  probe 
               104  JT cooler 
               105  treatment portion 
               106  supporting member 
               108  solenoid valve 
               109  CO 2  cylinder 
               110  reflux tube 
               111  infusion tube 
               111   a  rear-end side infusion portion of infusion tube 
               111   b  front-end side infusion portion of infusion tube 
               111   c  depressurizing portion of infusion tube 
               112  tube connector 
               113  gas discharge hole 
               114  horn 
               115  BLT (Bolt-clamped Langevin-type Transducer) 
               116  drive-voltage supply cable 
               117  driving power source 
               118  control signal cable 
               119  system controller