Abstract:
A vibration transmitting member for use with a clamp member. The vibration transmitting member provided with vibration from an ultrasonic transducer and including: a body having a distal portion with a surface and an opposite surface, the body further having a proximal portion; wherein: the body extending along a longitudinal axis extending from the proximal toward the distal portion, the surface opposes the clamp member and having a ridge extending along the longitudinal axis, the ridge extends toward the clamp member in a thickness direction more than other portions of the surface, the opposite surface opposes the surface and having a projection extending along the longitudinal axis, the projection protrudes more than other portions of the opposite surface in the thickness direction, and a maximum thickness of the distal portion is smaller than a maximum width of the distal portion in a width direction perpendicular to the thickness direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application is a continuation of PCT/JP2016/064640 filed on May 17, 2016, which is based upon and claims the benefit to JP 2015-107773 filed on May 27, 2015, the entire contents of each of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    Field 
         [0003]    The present application relates to a vibration transmitting member and a surgical apparatus. 
         [0004]    Prior Art 
         [0005]    For example, US 2011/288451 A1 discloses a surgical apparatus enabling dissection of living tissue during coagulation of the living tissue with use of high-frequency output and ultrasonic output in a state in which the living tissue is grasped. 
         [0006]    A distal end of a vibration transmitting member of such a surgical apparatus and a clamp member opposed to the vibration transmitting member to enable approach to and separation from the vibration transmitting member by turning are formed to be thin in consideration of a dissection performance of living tissue. Thus, a contact area between the vibration transmitting member and clamp member and the living tissue is small. Accordingly, such a surgical apparatus may not be suitable when treatment of the removal of living tissue such as a liver is conducted. Also, when the treatment of the removal of the living tissue is conducted, a blood vessel may be buried. In this case, surface pressure between the vibration transmitting member and clamp member and the blood vessel at the time of grasping the blood vessel is required to be lowered. 
       SUMMARY 
       [0007]    An object is to provide a vibration transmitting member and a surgical apparatus enabling treatment of the removal of living tissue such as a liver to be conducted appropriately and enabling a blood vessel or the like buried in the living tissue to be grasped appropriately. 
         [0008]    Accordingly, a vibration transmitting member is provided for use with a clamp member. The vibration transmitting member being provided with vibration from an ultrasonic transducer, the vibration transmitting member comprising: a body having a distal portion with a surface and an opposite surface, the body further having a proximal portion; wherein: the body extending along a longitudinal axis extending from the proximal portion toward the distal portion, the surface configured to oppose the clamp member, the surface having a ridge extending along the longitudinal axis, the ridge configured to extend toward the clamp member in a thickness direction of the distal portion more than other portions of the surface, the opposite surface configured to oppose the surface, the opposite surface having a projection extending along the longitudinal axis, the projection configured to protrude more than other portions of the opposite surface in the thickness direction, and a maximum thickness of the distal portion through the ridge and the projection in the thickness direction is smaller than a maximum width of the distal portion in a width direction perpendicular to the thickness direction. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0009]      FIG. 1  illustrates a schematic view of a surgical system according to first to fifth embodiments. 
           [0010]      FIG. 2  illustrates a schematic perspective view of a part around a distal portion of a vibration transmitting member and a clamp member in a surgical apparatus of the surgical system according to the first embodiment. 
           [0011]      FIG. 3A  illustrates a schematic side view of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the first embodiment. 
           [0012]      FIG. 3B  illustrates a schematic horizontal cross-sectional view along line  3 B- 3 B in  FIG. 3A  of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the first embodiment. 
           [0013]      FIG. 3C  illustrates a schematic horizontal cross-sectional view along line  3 C- 3 C in  FIG. 3A  of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the first embodiment. 
           [0014]      FIG. 3D  illustrates a schematic top view of the distal portion of the vibration transmitting member in the surgical apparatus of the surgical system according to the first embodiment. 
           [0015]      FIG. 4A  illustrates a schematic side view of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the second embodiment. 
           [0016]      FIG. 4B  illustrates a schematic horizontal cross-sectional view along line  4 B- 4 B in  FIG. 4A  of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the second embodiment. 
           [0017]      FIG. 4C  illustrates a schematic horizontal cross-sectional view along line  4 C- 4 C in  FIG. 4A  of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the second embodiment. 
           [0018]      FIG. 4D  illustrates a schematic top view of the distal portion of the vibration transmitting member in the surgical apparatus of the surgical system according to the second embodiment. 
           [0019]      FIG. 5  illustrates a schematic perspective view of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the third embodiment. 
           [0020]      FIG. 6  illustrates a schematic side view of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the fourth embodiment. 
           [0021]      FIG. 7A  illustrates a schematic side view of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the fifth embodiment. 
           [0022]      FIG. 7B  illustrates a schematic horizontal cross-sectional view along line  7 B- 7 B in  FIG. 7A  of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the fifth embodiment. 
           [0023]      FIG. 7C  illustrates a schematic horizontal cross-sectional view along line  7 C- 7 C in  FIG. 7A  of the part around the distal portion of the vibration transmitting member and the clamp member in the surgical apparatus of the surgical system according to the fifth embodiment. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0024]    Hereinbelow, embodiments will be described with reference to the drawings. 
         [0025]    A first embodiment will be described with reference to FIGS.  1  to  3 D. 
         [0026]    As illustrated in  FIG. 1 , a surgical system  10  according to the present embodiment includes a surgical apparatus  12 , an ultrasonic transducer  14 , and a controller  16 . The controller  16  includes an energy source (not illustrated) supplying the ultrasonic transducer  14  with energy generating appropriate ultrasonic vibration. The ultrasonic transducer  14  is arranged at a proximal end of a below-mentioned vibration transmitting member  26  and generates ultrasonic vibration to enable the vibration to be transmitted from the proximal portion to a distal portion along a longitudinal axis (center axis) C of the vibration transmitting member  26 . 
         [0027]    The not-illustrated energy source of the controller  16  can generate the ultrasonic vibration in the transducer  14  and apply high-frequency output to living tissue grasped between the below-mentioned vibration transmitting member  26  serving as a first electrode of the surgical apparatus  12  and electrode portions  56   a  and  56   b  included in a below-mentioned clamp member  28  serving as a second electrode. The controller can  16  include a processor including a CPU, an ASIC, or the like. 
         [0028]    As illustrated in  FIGS. 1 to 3A , the surgical apparatus  12  includes a handle unit  22 , a cylindrical sheath  24 , the vibration transmitting member (rod-like member)  26 , and the clamp member  28  used with the vibration transmitting member  26  and enabling approach to and separation from the vibration transmitting member  26 . The vibration transmitting member  26  is used with the clamp member  28  and can transmit vibration from the ultrasonic transducer  14 . 
         [0029]    As illustrated in  FIG. 1 , the handle unit  22  includes a housing  32  including a fixed handle  32   a , and a movable handle  34 . Inside the sheath  24 , a driving member  42  (refer to  FIG. 3A ) operating along an axial direction of the center axis C, interlocking with an operation of the movable handle  34 , is arranged. The driving member  42  can be formed in a cylindrical shape concentrically with the sheath  24 . The movable handle  34  can move between a separation position (open position) illustrated in  FIG. 1  separating from the fixed handle  32   a  of the housing  32  and an approach position (close position) approaching to the fixed handle  32   a  of the housing  32 . In the present embodiment, when the movable handle  34  is at the separation position, the clamp member  28  is at a separation position from a distal portion (treatment portion)  26   a  of the vibration transmitting member  26  as illustrated in  FIGS. 1 and 2 . Also, when the movable handle  34  is at the approach position, the clamp member  28  is at an approach position to the distal portion  26   a  of the vibration transmitting member  26  as illustrated in  FIG. 3A . 
         [0030]    Meanwhile, it is to be understood that the clamp member  28  may be at the approach position to the distal portion  26   a  of the vibration transmitting member  26  when the movable handle  34  is at the separation position and that the clamp member  28  may be at the separation position from the distal portion  26   a  of the vibration transmitting member  26  when the movable handle  34  is at the approach position. 
         [0031]    At a distal portion  24   a  of the sheath  24 , the clamp member  28  is turnably supported. As illustrated in  FIGS. 2, 3B, and 3C , the clamp member  28  includes a clamp member main body (turning body)  52 , a pressing pad  54  provided in the main body  52 , and the pair of electrode portions  56   a  and  56   b  provided in the main body  52 . 
         [0032]    The main body  52  of the clamp member  28  may be formed by a single body or by plural bodies such as two bodies. In a case in which the main body  52  is formed by the plural bodies, a known so-called seesaw jaw or wiper jaw can be used. 
         [0033]    The main body  52  of the clamp member  28  is supported at the distal portion  24   a  of the sheath  24  to be turnable by a main turning shaft  62 , for example. The main body  52  is supported at a distal portion of the driving member  42  to be turnable by a moving and turning shaft (distal-side turning shaft)  64 . The main turning shaft  62  and the moving and turning shaft (distal-side turning shaft)  64  can be parallel to each other and can be perpendicular to the center axis C. When the driving member  42  moves forward along the center axis (longitudinal axis) C with respect to the sheath  24  in response to an operation of the movable handle  34  with respect to the housing  32 , the driving member  42  presses the main body  52  to a front side of the sheath  24  approximately in parallel with the center axis C by means of the moving and turning shaft  64 . Since positional relationship among the main turning shaft  62 , the main body  52 , and the distal portion  24   a  of the sheath  24  does not change, the main body  52  closes toward the distal portion  26   a  of the vibration transmitting member  26 . Conversely, when the driving member  42  moves backward along the center axis C with respect to the sheath  24  in response to an operation of the movable handle  34 , the driving member  42  pulls the main body  52  to a backside of the sheath  24  in parallel with the center axis C by means of the moving and turning shaft  64 . Thus, the main body  52  opens away from the distal portion  26   a  of the vibration transmitting member  26 . That is, the main body  52  of the clamp member  28  is movable between the approach position (close position) approaching to the vibration transmitting member  26  and the separation position (open position) separating from the vibration transmitting member  26  by means of the operations of the movable handle  34 . 
         [0034]    The pressing pad  54  is provided at a position in the main body close to a below-mentioned treatment surface  82  at the distal portion  26   a  of the vibration transmitting member  26  in a state of being opposed to the treatment surface  82 . The pressing pad  54  is arranged between the electrode portions  56   a  and  56   b  in the main body  52 . The pressing pad  54  abuts on a below-mentioned dissecting area  82   a  of the treatment surface  82  at the distal portion  26   a  of the vibration transmitting member  26  when the main body  52  is at the approach position and separates from the treatment surface  82  at the distal portion  26   a  of the vibration transmitting member  26  along with movement of the main body  52  when the main body  52  is at the separation position. The pressing pad  54  is made of a material having electric insulation, heat resistance, and abrasion resistance. As a material for the pressing pad  54 , a PTFE material can be used, for example. 
         [0035]    In the present embodiment, in a case in which the clamp member  28  is at the approach position, especially the dissecting area  82   a  of the treatment surface  82  at the distal portion  26   a  of the vibration transmitting member  26  can abut on the pressing pad  54  but does not abut on the electrode portions  56   a  and  56   b . Thus, when the treatment surface  82  at the distal portion  26   a  of the vibration transmitting member  26  is used as one electrode while the electrode portions  56   a  and  56   b  of the clamp member  28  are used as the other electrode, and living tissue is clamped between the electrodes, bipolar treatment can be conducted to the living tissue. 
         [0036]    Meanwhile, a heater may be used instead of the electrode portions  56   a  and  56   b , or an equal material to the pressing pad  54  may be provided on the surface instead of the electrode portions  56   a  and  56   b.    
         [0037]    The vibration transmitting member (rod-like member)  26  is inserted into the sheath  24 . The vibration transmitting member  26  is made of a material having a good vibration transmitting characteristic such as a titanium alloy material and an aluminum alloy material. The vibration transmitting member  26  extends from the proximal portion to which the ultrasonic transducer  14  is connected toward the distal portion. In the vibration transmitting member  26 , vibration is transmitted from the proximal portion toward the distal portion in response to input of vibration from the ultrasonic transducer  14 . The vibration transmitting member  26  is conductive when the vibration transmitting member  26  is used as one of high-frequency electrodes. The vibration transmitting member  26  can be arranged on the center axis C of the sheath  24 . 
         [0038]    From the proximal end to the distal end of the vibration transmitting member  26 , vibration having an appropriate frequency is transmitted by the ultrasonic transducer  14  attached to the proximal end of the vibration transmitting member  26 . Thus, a length from the proximal portion to the distal portion of the vibration transmitting member  26  is set in accordance with the frequency of the vibration output by the ultrasonic transducer  14 . Particularly, the distal end of the vibration transmitting member  26  is set at an antinode position of the vibration since the distal end conducts appropriate treatment to living tissue in a state in which the vibration is transmitted. An outer circumferential surface of the vibration transmitting member  26  located at a node position of the vibration in a state in which the vibration is transmitted to the vibration transmitting member  26  is provided between the outer circumferential surface and an inner circumferential surface of the sheath  24  with a ring-like member  27  having electric insulation and heat resistance. That is, in the treatment portion  26   a  of the vibration transmitting member  26 , a distal end corresponds to the antinode position of the vibration while a proximal end corresponds to the node position of the vibration inside the sheath  24 , and a length of the treatment portion  26   a  corresponds to a quarter wavelength of the vibration (vibrational wave) output by the ultrasonic transducer  14 . Meanwhile, the treatment portion  26   a  can be formed to be symmetric or approximately symmetric across an opening/closing surface including the center axis C to which the clamp member  28  turns. Also, the treatment portion  26   a  can be formed to be symmetric or approximately symmetric across the center axis C in a direction along an opening/closing direction of the clamp member  28 . 
         [0039]    As illustrated in  FIG. 3A , the distal portion of the treatment portion  26   a  of the vibration transmitting member  26  according to the present embodiment includes a treatment area (parallel area)  72  provided to be parallel to or approximately parallel to the center axis C and adapted to conduct treatment to living tissue, a middle area  74  formed on a proximal side of the treatment area  72 , and a rod-like area  76  formed on a proximal side of the middle area  74 . The rod-like area  76  can have an approximately equal diameter, for example, has a circular horizontal cross-sectional surface, and is formed in a rod shape at an appropriate position along the center axis C. Meanwhile, in the present embodiment, a first node position of the vibration from the distal end is located in the rod-like area  76 . In the middle area  74 , a horizontal cross-sectional surface thereof smoothly changes from the rod-like area  76  at the proximal end thereof to the treatment area  72  at a distal end thereof. In the present embodiment, in the middle area  74 , a thickness along the opening/closing direction in which the clamp member  28  moves by turning can be smaller gradually from the proximal end to the distal end along the center axis C in  FIGS. 3A and 3D . At this time, the middle area  74  can be formed to have a symmetric or approximately symmetric thickness across the center axis C. Conversely, in the present embodiment, in the middle area  74 , a length in a width direction perpendicular to the opening/closing direction of the clamp member  28  can be approximately equal regardless of an appropriate position along the center axis C in  FIGS. 3A and 3D . 
         [0040]    The treatment area  72  includes the treatment surface  82 , a back surface  84  opposed to the treatment surface  82 , and side surfaces  86   a  and  86   b  between the treatment surface  82  and the back surface  84 . In the treatment area  72  of the treatment portion  26   a , a thickness T along the opening/closing direction in which the clamp member  28  is to move by turning is smaller than a width W along the width direction perpendicular to the opening/closing direction. Thus, the treatment portion  26   a  is formed approximately in a flat shape. In the present embodiment, the width W in the width direction can be equal from a distal portion of the treatment area  72  of the treatment portion  26   a  to an appropriate position such as the rod-like area  76  at the proximal portion of the treatment portion  26   a . As illustrated in  FIGS. 3B and 3C , in the present embodiment, a thickness (height) TU of an upper part and a thickness (height) TL of a lower part with respect to the longitudinal axis C can be equal. 
         [0041]    The treatment surface  82  includes the dissecting area  82   a  enabling abutment on the pressing pad  54  and transmitting ultrasonic vibration thereto to enable dissection of living tissue and sealing areas  82   b  and  82   c  formed adjacent to the dissecting area  82   a  in the width direction and enabling coagulation and sealing of the living tissue by means of high-frequency output generated by electric conduction between the sealing areas  82   b  and  82   c  and the electrode portions  56   a  and  56   b  of the clamp member  28  via the living tissue. As illustrated in  FIGS. 3B and 3C , the dissecting area  82   a  and the sealing areas  82   b  and  82   c  are formed along the longitudinal axis C. The dissecting area  82   a  is at a top portion along the opening/closing direction of the clamp member  28  and has an appropriate width, for example, to form a ridge (ridge line). This dissecting area (ridge)  82   a  extends along the longitudinal axis C and is located on the opening/closing surface to which the clamp member  28  is to move by turning. The sealing areas  82   b  and  82   c  are formed successively to the dissecting area  82   a  and are respectively formed as inclined surfaces elongated along the longitudinal axis C. The ridge  82   a  is configured to extend toward the clamp member  28  in a thickness direction (the opening/closing direction) of the distal portion  26   a  more than other portion of the treatment surface  82 . A thickness of the distal portion  26   a  through the ridge  82   a  in the thickness direction is smaller than a width of the distal portion  26   a  in a width direction perpendicular to the thickness direction. 
         [0042]    The sealing areas  82   b  and  82   c  may be flat surfaces or curved surfaces. As illustrated in  FIGS. 3B and 3C , the thickness T of the treatment area  72  is thinner at a position farther than a position including the center axis C (position including the dissecting area  82   a ) along the width direction. 
         [0043]    As illustrated in  FIG. 1 , the housing  32  is provided with first and second switches  92  and  94 . When the first switch  92  is pressed, bipolar high-frequency output is performed between the vibration transmitting member  26  serving as the first electrode and the electrode portions  56   a  and  56   b  of the clamp member  28  serving as the second electrode. Thus, by pressing the first switch  92 , coagulation of living tissue or sealing of a blood vessel is conducted between the vibration transmitting member  26  and the electrode portions  56   a  and  56   b  of the clamp member  28 . When the second switch  94  is pressed, ultrasonic output and bipolar high-frequency output are performed. Thus, living tissue is dissected while the living tissue is coagulated, or a blood vessel is dissected while the blood vessel is sealed. 
         [0044]    Next, actions of the surgical system  10  according to the present embodiment will be described. Here, description is provided, using liver tissue as a treated target, for example. 
         [0045]    The movable handle  34  is moved closer to the fixed handle  32   a  of the housing  32  to move the clamp member  28  closer to the treatment surface  82  of the vibration transmitting member  26 . Liver tissue is then grasped between the pressing pad  54  and the electrode portions  56   a  and  56   b  of the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26 . At this time, the width W of the treatment surface  82  of the vibration transmitting member  26  is formed to be longer than the thickness T, and a width of the clamp member  28  is similarly formed to be long to correspond to the width W of the treatment surface  82  of the vibration transmitting member  26 . Thus, an area of the treatment surface is formed to be large. Accordingly, since the width of the treatment surface  82  is long, a contact area of the treatment surface  82  of the vibration transmitting member  26  and the clamp member  28  is large at the time of contacting the liver tissue, and the treatment surface  82  of the vibration transmitting member  26  and the clamp member  28  are easily grasp the liver tissue. The pressing pad  54  and the electrode portions  56   a  and  56   b  of the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26  are formed to clamp the liver tissue therebetween. Also, when the living tissue is grasped between the pressing pad  54  and the electrode portions  56   a  and  56   b  of the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26 , and a compressing force (grasping force) is applied, the compressing force is distributed over the contact surface since the contact area between the treatment surface  82  and the living tissue is large. Accordingly, in the treatment surface  82 , an action of widely pressing and compressing the living tissue is larger than an action of dissecting the living tissue by focusing the compressing force on a part. The treatment surface  82  is suitable for the removal of the liver tissue, especially liver parenchyma. 
         [0046]    Meanwhile, at this time, no operation of the first switch  92  or the second switch  94  is required. That is, in a case in which treatment of the removal of the liver tissue is conducted by means of the surgical apparatus  12  according to the present embodiment, the high-frequency output and the ultrasonic output are not required. 
         [0047]    In case of grasping a blood vessel between the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26 , the contact area between the treatment surface  82  of the vibration transmitting member  26  and the living tissue is large. Thus, surface pressure when the blood vessel is grasped between the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26  is distributed. Accordingly, when the blood vessel in the liver tissue is grasped between the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26 , it is possible to prevent the blood vessel from being damaged and bleeding by a mechanical force of the compressing force (grasping force). 
         [0048]    The movable handle  34  is moved away from the fixed handle  32   a  of the housing  32  to move the clamp member  28  away from the treatment surface  82  of the vibration transmitting member  26 . The movable handle  34  is then moved closer to the fixed handle  32   a  of the housing  32  again to move the clamp member  28  closer to the treatment surface  82  of the vibration transmitting member  26 , and adjacent liver tissue is removed in a similar manner to the above. 
         [0049]    As described above, when the liver tissue is removed, the blood vessel in the liver may appear. In this case, the blood vessel is grasped between the pressing pad  54  of the clamp member  28  and the treatment surface  82  of the vibration transmitting member  26 . When the first switch  92  is pressed in this state, the blood vessel is coagulated by the action of the high-frequency output. Also, when the second switch  94  is pressed, the blood vessel is dissected mainly by the action of the ultrasonic vibration while the blood vessel is coagulated mainly by the action of the high-frequency output. Specifically, the blood vessel is dissected at the dissecting area  82   a  of the treatment surface  82  by the action of the ultrasonic output while the blood vessel is coagulated at the sealing areas  82   b  and  82   c  of the treatment surface  82  by the action of the high-frequency output. 
         [0050]    As described above, the present embodiment can achieve the following advantages. 
         [0051]    The width W of the treatment surface  82  in the vibration transmitting member  26  opposed to the clamp member  28  is wider than the thickness T, and the vibration transmitting member  26  is formed approximately in the flat shape. Accordingly, an area in the treatment surface  82  of the vibration transmitting member  26  abutting on liver tissue or the like can be large, and tissue having a larger area can be clamped and compressed between the clamp member  28  and the treatment surface  82 . Also, even in a case in which a blood vessel is unintentionally grasped when the treatment surface  82  grabs the liver tissue or the like, the contact area between the blood vessel and the treatment surface  82  is set to be large, and the surface pressure of the treatment surface  82  to the blood vessel can be distributed. Accordingly, when the blood vessel is grasped between the treatment surface  82  of the vibration transmitting member  26  and the clamp member  28 , it is possible to prevent the blood vessel from being damaged and bleeding by a mechanical force of the compressing force (grasping force). 
         [0052]    When the blood vessel is grasped, the blood vessel can be coagulated by the high-frequency output. Also, the blood vessel can be dissected while being coagulated by the high-frequency output and the ultrasonic output. 
         [0053]    Thus, the present embodiment can provide the vibration transmitting member  26  and the surgical apparatus  12  enabling treatment of the removal of living tissue such as a liver to be conducted appropriately and enabling a blood vessel or the like buried in the living tissue to be grasped appropriately. 
         [0054]    Next, a second embodiment will be described with reference to  FIGS. 4A to 4D . The present embodiment is a modification example of the first embodiment. Members similar to or having similar functions to those described in the first embodiment are shown with the same reference numerals as much as possible, and detailed description of such similar components is omitted. 
         [0055]    As illustrated in  FIGS. 4A to 4D , the treatment portion  26   a  as the distal portion of the vibration transmitting member  26  according to the present embodiment has a different width in the width direction and a different horizontal cross-sectional shape depending on a position along the longitudinal axis C. 
         [0056]    The treatment area  72  of the treatment portion  26   a  can be formed to be symmetric or approximately symmetric across the center axis C in the width direction. The treatment area  72  of the treatment portion  26   a  includes a distal area  72   a , a width change area  72   b  provided on a proximal side of the distal area  72   a , and a proximal area  72   c  provided on a proximal side of the width change area  72   b . That is, the treatment area  72  of the treatment portion  26   a  includes the width change area  72   b  between the distal area  72   a  and the proximal area  72   c , as well as the distal area  72   a  and the proximal area  72   c , in a quarter wavelength area of the vibrational wave output by the ultrasonic transducer  14  from the distal portion to the proximal side (area approximately over the entire length of the treatment portion  26   a ). The distal area  72   a  illustrated in  FIG. 4B  has an approximately constant width W 1  in the width direction and an approximately constant horizontal cross-sectional shape from a position close to a distal end thereof to the proximal end. As a matter of course, the distal end of the distal area  72   a  is formed in an obtuse shape. As illustrated in  FIG. 4D , a width of the width change area  72   b  in the width direction is gradually, such as successively, reduced from the proximal end of the distal area  72   a  to a distal end of the proximal area  72   c . That is, the width change area  72   b  has a wider width in the width direction and a larger horizontal cross-sectional area at a position closer to the distal area  72   a  and has a shorter width in the width direction and a smaller horizontal cross-sectional area at a position closer to the proximal area  72   c . Further, the proximal area  72   c  has an approximately constant width W 2  in the width direction and an approximately constant horizontal cross-sectional shape from a position close to the distal end thereof to a proximal end thereof. Accordingly, the width W 1  of the distal area  72   a  in the width direction perpendicular to the longitudinal axis C is wider than the width W 2  of the proximal area  72   c  in the width direction. That is, in the treatment portion  26   a , the width W 1  in the width direction on a cross-section of the distal area  72   a  perpendicular to the longitudinal axis C is wider than the width W 2  in the width direction on a cross-section of the proximal area  72   c.    
         [0057]    Also, a cross-sectional area D 1  in the distal area  72   a  illustrated in  FIG. 4B  is larger than a cross-sectional area D 2  in the proximal area  72   c  illustrated in  FIG. 4C . Also, a cross-sectional area of the width change area  72   b  is as large as a cross-sectional area between the cross-sectional area D 1  in the distal area  72   a  and the cross-sectional area D 2  in the proximal area  72   c  although it is not illustrated. More specifically, the cross-sectional area of the width change area  72   b  is gradually reduced from the proximal end of the distal area  72   a  to the distal end of the proximal area  72   c . The cross-sectional area of the width change area  72   b  can correspond at a distal end thereof to the cross-sectional area D 1  of the proximal end of the distal area  72   a  and correspond at the proximal end thereof to the cross-sectional area D 2  of the distal end of the proximal area  72   c . Accordingly, the cross-sectional area D 1  of the distal area  72   a  perpendicular to the longitudinal axis C is larger than the cross-sectional area D 2  of the proximal area  72   c  perpendicular to the longitudinal axis C. 
         [0058]    In the treatment area  72  of the treatment portion  26   a , the width change area  72   b  and the distal area  72   a  are formed to be wider than the proximal area  72   c . That is, the proximal area  72   c  is formed to be narrower than the width change area  72   b  and the distal area  72   a . Thus, in a case in which the width change area  72   b  or the distal area  72   a  is checked from the proximal side of the vibration transmitting member  26  and the clamp member  28  with use of an endoscope (not illustrated), for example, the width change area  72   b  or the distal area  72   a  can be checked through a part at which no flesh exists. Accordingly, the treatment portion  26   a  of the vibration transmitting member  26  according to the present embodiment is formed to facilitate checking of a treatment state with use of the endoscope. 
         [0059]    As illustrated in  FIG. 4D , when a line along an external edge (side surface  86   a  or  86   b ) in the width direction of the width change area  72   b  is virtually extended toward the longitudinal axis C, an angle θ between the longitudinal axis C and the virtual line illustrated by the dashed line can be set to 30° or less, for example. It is empirically found that, when the angle θ is around 5°, for example, generation of mist, that is, generation of cavitation, can be restricted in the width change area  72   b  between the distal area  72   a  and the proximal area  72   c  in a state in which vibration is transmitted from the ultrasonic transducer  14  to the vibration transmitting member  26 . This angle θ can be changed to 10°, 20°, or the like as appropriate. Also, although each of the side surfaces  86   a  and  86   b  of the width change area  72   b  is a linearly-extended inclined surface in the above embodiment, each of the side surfaces  86   a  and  86   b  may be formed to change the width continuously by combining a plurality of inclined surfaces. For example, each of the side surfaces  86   a  and  86   b  may be formed to change the width from the proximal area  72   c  toward the distal area  72   a  in a multistage manner, in which an area whose angle θ between the longitudinal axis C and the virtual line is 5°, an area whose angle θ is 10°, and the like are arranged. Also, although each of the side surfaces  86   a  and  86   b  of the width change area  72   b  is the linearly-extended inclined surface in the above embodiment, each of the side surfaces  86   a  and  86   b  of the width change area  72   b  may be formed as a curved surface, and the angle θ between a tangential line of the curved surface and the longitudinal axis C may be 30° or less. 
         [0060]    Especially at the time of treatment, the distal end of the treatment portion  26   a  of the vibration transmitting member  26  and the distal end of the clamp member  28  are moved finely. The width change area  72   b  and the proximal area  72   c  are formed to be narrower than the distal area  72   a . Thus, even in a case in which the temperature of the treatment portion  26   a  of the vibration transmitting member  26  is higher than a temperature denaturalizing protein of living tissue (e.g., approximately 60° C.) due to the high-frequency output or the like, for example, the width change area  72   b  and the proximal area  72   c  are harder to contact the living tissue than in a state in which the width change area  72   b  and the proximal area  72   c  have the same widths as that of the distal area  72   a . Accordingly, by using the vibration transmitting member  26  according to the present embodiment, generation of thermal spread can be restricted when the treatment portion  26   a  of the vibration transmitting member  26  and the clamp member  28  are moved as appropriate. 
         [0061]    Thus, the present embodiment can provide the vibration transmitting member  26  and the surgical apparatus  12  enabling restriction of thermal spread while securing insertability into a small hole and visibility of a distal portion. 
         [0062]    Next, a third embodiment will be described with reference to  FIG. 5 . The present embodiment is a modification example of the first and second embodiments. Members similar to or having similar functions to those described in the first and second embodiments are shown with the same reference numerals as much as possible, and detailed description of such similar components is omitted. It is to be understood in the present embodiment that the treatment portion  26   a  of the vibration transmitting member  26  may be either one having a constant width as described in the first embodiment or one having the distal area  72   a , the width change area  72   b , and the proximal area  72   c  and changing a width depending on a position as described in the second embodiment. 
         [0063]    As illustrated in  FIG. 5 , the treatment area  72  of the distal portion  26   a  of the vibration transmitting member  26  is bent at a bent portion  78  in one direction from a straight state. Similarly, the clamp member  28 , as well as the treatment portion  26   a  of the vibration transmitting member  26 , is bent at a bent portion  58  in one direction from a straight state. Here, as an example, a part from the distal end to the bent portion  78  of the vibration transmitting member  26  is bent, and a part from the bent portion  78  to the proximal side is straight. Similarly, a part from the distal end to the bent portion  58  of the clamp member  28  is bent, and a part from the bent portion  58  to the proximal side is straight. 
         [0064]    Meanwhile, it is to be understood that a part from the distal end of the treatment area  72  to the distal end of the middle area  74  in the treatment portion  26   a  of the vibration transmitting member  26  can be bent to form the bent portion  78 . That is, the treatment portion  26   a  of the vibration transmitting member  26  has only to include the bent portion  78  between the distal end of the treatment area  72  and the distal end of the middle area  74 . Thus, the treatment area  72  of the treatment portion  26   a  includes the bent portion  78  between the distal end of the treatment area  72  and the proximal end of the treatment area  72  in the quarter wavelength area of the vibrational wave output by the ultrasonic transducer  14  from the distal portion to the proximal side (area approximately over the entire length of the treatment portion  26   a ). The shape of the treatment portion  26   a  of the vibration transmitting member  26  may be formed as appropriate as long as easiness of treatment is secured as described below. 
         [0065]    In a case in which treatment of the removal of liver tissue in a curved shape is to be conducted without using energy, when the distal portion  26   a  of the vibration transmitting member  26  is straight as described in the first and second embodiments, a single-time treatment area is in a straight shape. Thus, to conduct the treatment of the removal of the liver tissue in the curved shape, small straight-shaped treatment needs to be repeated while the direction of the distal portion  26   a  is changed. Conversely, since the treatment portion  26   a  of the vibration transmitting member  26  according to the present embodiment is bent in one direction, a single-time treatment area is approximately in an arc. Accordingly, the operation of repeating the small straight-shaped treatment can be omitted at the time of forming the treatment area in the curved shape. For this reason, when the liver tissue is to be dissected annularly, for example, existence of the bent portion  78  enables single treatment to be longer in length than the small straight-shaped treatment and to be conducted in a wider range. Accordingly, in a case in which the treatment portion  26   a  includes the bent portion  78 , the number of times of opening/closing the clamp member  28  with respect to the treatment portion  26   a  can be decreased. That is, the number of times of movement of the vibration transmitting member  26  and the clamp member  28  and the number of times of turning of the clamp member  28  can be decreased. Also, due to the bent portion  78 , at the time of forming the treatment area in the curved shape, it is possible to prevent excessive dissection of a dissected target such as liver tissue and to form a smoother treatment area. 
         [0066]    Also, since the distal portion  26   a  of the vibration transmitting member  26  is bent, visibility of the clamp member  28  and the distal portion  26   a  of the vibration transmitting member  26  with use of a not-illustrated endoscope in laparoscopic surgery can be improved. 
         [0067]    Next, a fourth embodiment will be described with reference to  FIG. 6 . The present embodiment is a modification example of the first to third embodiments. Members similar to or having similar functions to those described in the first to third embodiments are shown with the same reference numerals as much as possible, and detailed description of such similar components is omitted. In the present embodiment, the treatment portion  26   a  of the vibration transmitting member  26  may be straight as described in the first and second embodiments or bent as described in the third embodiment. 
         [0068]    As illustrated in  FIG. 6 , a distal end of the back surface  84  opposed to the treatment surface  82  in the treatment area  72  of the distal portion  26   a  of the vibration transmitting member  26  is provided with a cavitation generating surface  84   a  actively generating cavitation in an intended direction when vibration from the ultrasonic transducer  14  is transmitted to the distal end of the vibration transmitting member  26 . The cavitation generating surface  84   a  is formed as a curved surface. The cavitation generating surface  84   a  generates the cavitation in a normal direction thereof when the vibration from the ultrasonic transducer  14  is transmitted to the distal end of the vibration transmitting member  26 . 
         [0069]    In this manner, the curved cavitation generating surface  84   a  is formed at the distal end of the back surface  84  in the treatment area  72  of the distal portion  26   a  of the vibration transmitting member  26 . Thus, for example, the cavitation generating surface  84   a  can be brought into contact with liver tissue, and when the vibration from the ultrasonic transducer  14  is transmitted to the distal end of the vibration transmitting member  26 , the liver tissue can be emulsified by the cavitation. 
         [0070]    Next, a fifth embodiment will be described with reference to  FIGS. 7A to 7C . The present embodiment is a modification example of the first to fourth embodiments. Members similar to or having similar functions to those described in the first to fourth embodiments are shown with the same reference numerals as much as possible, and detailed description of such similar components is omitted. 
         [0071]    As illustrated in  FIGS. 7A to 7C , when the clamp member  28  is closed with respect to the vibration transmitting member  26 , the distal portion  26   a  of the vibration transmitting member  26  is supplied around a proximal end of the pressing pad  54  with highest stress. As illustrated in  FIG. 7A , the middle area  74  of the treatment portion  26   a  of the vibration transmitting member  26  according to the present embodiment includes a short area  74   a  on the side of the treatment surface  82  and a long area  74   b  on the side of the back surface  84 . The long area  74   b  on the side of the back surface  84  is longer than the short area  74   a  on the side of the treatment surface  82 . Proximal positions of the short area  74   a  and the long area  74   b  along the center axis C are at equal or approximately equal positions, that is, at a position of a distal end of the rod-like area  76 . The short area  74   a  is formed continuously to the treatment surface  82 . The long area  74   b  is formed continuously to the back surface  84  on a proximal side of the back surface  84 . Thus, the middle area  74  of the distal portion  26   a  of the vibration transmitting member  26  according to the present embodiment has an upper side and a lower side asymmetric across the longitudinal axis C in  FIG. 7A  and forms a longer thick part than the middle area  74  of the distal portion  26   a  of the vibration transmitting member  26  described in the first to fourth embodiments. That is, the treatment area  72  according to the present embodiment includes not only a parallel part to the center axis C but also a part of a thick portion  88 . 
         [0072]    Here, as illustrated in  FIGS. 7A and 7B , in the middle area  74 , the distance TU from the center axis C to the top portion (dissecting area)  82   a  of the treatment surface  82  is shorter than a distance TL 1  from the center axis C to a top portion  85  of the back surface  84 . Thus, the long area  74   b  of the middle area  74  is provided with the thick portion  88 , which is thicker than the short area  74   a . That is, the long area  74   b  of the middle area  74  includes the thick portion  88 . Meanwhile, as illustrated in  FIGS. 7A  and  7 C, in the treatment area  72 , the distance TU from the center axis C to the top portion (dissecting area)  82   a  of the treatment surface  82  is approximately equal to the distance TL from the center axis C to the top portion  85  of the back surface  84 . Meanwhile, the top portion (dissecting area)  82   a  of the treatment surface  82  is an abutting surface on which the pressing pad  54  is to abut. 
         [0073]    Consequently, in the present embodiment, the treatment area (parallel area)  72  provided to be parallel to or approximately parallel to the center axis C and adapted to conduct treatment to living tissue is shorter on the back surface  84  than those described in the first to fourth embodiments. On the other hand, the treatment area (parallel area)  72  provided to be parallel to or approximately parallel to the center axis C and adapted to conduct treatment to living tissue can be formed on the treatment surface  82  to be similar to those described in the first to fourth embodiments. That is, the thick portion  88  of the back surface  84  has a part which is not parallel to the longitudinal axis C. As a matter of course, a part of the back surface  84  located further on the distal side than the thick portion  88  can be parallel to the longitudinal axis C. 
         [0074]    In this manner, the thick portion  88  is formed on the back surface  84  on the opposite side of the treatment surface  82  with the longitudinal axis C, extended from the proximal portion to the distal portion around an abutting part on which the proximal end of the pressing pad  54  along the longitudinal axis C in the dissecting area  82   a  abuts, interposed therebetween. The thick portion  88  is thicker than the part continued to the treatment surface  82  with the longitudinal axis C interposed therebetween from the distal side toward the proximal side along the longitudinal axis C. Also, in a state in which the proximal end of the pressing pad  54  of the clamp member  28  abuts on the dissecting area  82   a , the proximal end of the pressing pad  54  of the clamp member  28  is located between a distal end and a proximal end of the thick portion  88  along the longitudinal axis C. That is, the thick portion  88  is formed to be gradually thicker along the longitudinal axis C from a part in the dissecting area  82   a  further on the distal side than the proximal position of the pressing pad  54  along the longitudinal axis C toward a part further on the proximal side than the proximal position. 
         [0075]    Thus, due to the thick portion  88 , the distal portion  26   a  of the vibration transmitting member  26  according to the present embodiment, especially the proximal end of the pressing pad  54 , can improve resistance to stress more than the distal portion  26   a  of the vibration transmitting member  26  described in the first to fourth embodiments. Consequently, the amount of deformation of the treatment area  72  of the distal portion  26   a  of the vibration transmitting member  26  can be restricted. Thus, according to the present embodiment, it is possible to provide the vibration transmitting member  26  and the surgical apparatus  12  enabling resistance to stress in grasping to be secured without influencing treatment performance even in a case of proceeding with size reduction (diameter reduction) of the vibration transmitting member  26  and to restrict to the minimum changes in center of gravity on respective vertical cross-sectional surfaces to the longitudinal axis C and vibration destabilizing elements resulting from the discontinuous changes. 
         [0076]    Meanwhile, the bent portion  78  described in the fourth embodiment can be formed at an appropriate position although it is not illustrated. That is, for example, the bent portion  78  may be formed at a part including the thick portion  88 , at the treatment area  72 , or at both the parts. 
         [0077]    Several embodiments have specifically been described above with reference to the drawings. However, the present invention is not limited to the aforementioned embodiments but includes every embodiment carried out without departing from the spirit and scope thereof.