Abstract:
Local excessive laser radiation is prevented, and uniform laser radiation is performed in a target treatment region. Provided is a laser ablation device including: a light source that emits laser light for cauterizing an affected area; a fiber that is provided in an insertion portion and that guides the laser light emitted from the light source to radiate the laser light from an insertion-portion distal end; and a first drive unit that is provided on the fiber and that vibrates the fiber with a first period.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a continuation of International Application PCT/JP2013/074632, with an international filing date of Sep. 12, 2013, which is hereby incorporated by reference herein in its entirety. This application claims the benefit of Japanese Patent Application No. 2012-249519, filed on Nov. 13, 2012, the content of which is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a laser ablation device. 
       BACKGROUND ART 
       [0003]    In the conventional art, a laser ablation catheter with which laser light is radiated onto affected tissue from an insertion portion that emits laser light having high-density energy, thus cauterizing the affected tissue, has been known (for example, Japanese Unexamined Patent Application, Publication No. Hei 7-8502). The laser ablation catheter is used mainly to perform arrhythmia treatment and has the advantage, for patients, that only a minimum region into which the laser ablation catheter can be inserted needs to be incised, thereby making it possible to cauterize an affected area, which allows minimally invasive surgery to be performed. 
       CITATION LIST 
     Patent Literature 
     SUMMARY OF INVENTION 
     Technical Problem 
       [0004]    With the above-described laser ablation catheter, because laser light having high energy is radiated in a linear fashion, the laser cauterization performance at the affected area is high. An operator manually vibrates an insertion portion and operates the laser ablation catheter so as to prevent laser light from being locally and excessively radiated, this requires a highly-skilled operation. Particularly in a narrow space in the pericardium, manipulations performed by the operator at an insertion-portion base end to be transferred to an insertion-portion distal endare limited. Although the amount of light, the radiation region, and the radiation time are specified for laser radiation for treatment, because the density of laser radiation differs depending on the manipulation route, uneven radiation occurs. 
         [0005]    The present invention is a laser ablation device that prevents local excessive laser radiation and that performs uniform laser radiation in a target treatment region. 
       Solution to Problem 
       [0006]    According to one aspect, the present invention provides a laser ablation device including: a light source that emits laser light for cauterizing an affected area; a fiber that is provided in an insertion portion and that guides the laser light emitted from the light source to radiate the laser light from an insertion-portion distal end; and a first drive unit that is provided on the fiber and that vibrates the fiber with a first period. 
         [0007]    In the above-described aspect, it is preferable to further include a second drive unit that vibrates the fiber with a second period. 
         [0008]    It is possible to set the first period and the second period to different periods or also to the same period. 
         [0009]    In the above-described aspect, it is preferable that the amplitude produced by the second drive unit be larger than the amplitude produced by the first drive unit. 
         [0010]    In the above-described aspect, it is preferable that the first drive unit be provided closer to a distal end of the fiber than the second drive unit; and the second period be longer than the first period. 
         [0011]    In the above-described invention, it is preferable that the first drive unit be provided closer to a distal end of the fiber than the second drive unit; and the second period be a period n times (n is an integer) the first period. 
         [0012]    In the above-described aspect, it is preferable that the fiber be made to perform rotational motions by the first drive unit and the second drive unit; and the number of rotations of the fiber due to the first drive unit be faster than the number of rotations of the fiber due to the second drive unit. 
         [0013]    The first drive unit and the second drive unit allow the fiber to perform a resonant motion, raster scanning, spiral scanning, and scanning obtained by combining different types of scanning. 
         [0014]    It is preferable that further including one or more other drive units for periodically vibrating the fiber. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0015]      FIG. 1  is a view showing the overall configuration of a laser ablation device according to a first embodiment of the present invention. 
           [0016]      FIGS. 2A to 2C  show an insertion portion of the laser ablation device according to the first embodiment of the present invention:  FIG. 2A  is a view showing the overall insertion portion;  FIG. 2B  is a view showing a state in which a shaft and a fiber are fixed; and  FIG. 2C  is a cross-sectional view cut along the line A-A′ in  FIG. 2B . 
           [0017]      FIG. 3  is a view showing the overall configuration of a laser ablation device according to a second embodiment of the present invention. 
           [0018]      FIGS. 4A to 4D  show an insertion portion of the laser ablation device according to the second embodiment of the present invention:  FIG. 4A  is a view showing the overall insertion portion;  FIG. 4B  is a view showing a state in which a shaft and a fiber are fixed;  FIG. 4C  is a cross-sectional view cut along the line A-A′ in  FIG. 4B ; and  FIG. 4D  is a cross-sectional view cut along the line B-B′ in  FIG. 4B . 
           [0019]      FIGS. 5A and 5B  show example laser-light radiation trajectories produced by the fiber of the laser ablation device according to the second embodiment of the present invention. 
           [0020]      FIG. 6  is a view showing the overall configuration of a laser ablation device according to a third embodiment of the present invention. 
           [0021]      FIG. 7  is a view showing an insertion portion of the laser ablation device according to the third embodiment of the present invention. 
           [0022]      FIGS. 8A to 8C  show example laser-light radiation trajectories produced by a fiber of the laser ablation device according to the third embodiment of the present invention. 
           [0023]      FIG. 9  is a view showing an insertion portion of a laser ablation device according to a modification of the third embodiment of the present invention. 
           [0024]      FIGS. 10A to 100  show example laser-light radiation trajectories produced by a fiber of the laser ablation device according to the modification of the third embodiment of the present invention. 
           [0025]      FIGS. 11A and 11B  show other examples of insertion portions of laser ablation devices according to the present invention. 
           [0026]      FIGS. 12A to 12C  show example laser-light radiation trajectories produced by fibers of the laser ablation devices shown in  FIGS. 11A and 11B . 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
       [0027]    A laser ablation device  10  according to a first embodiment of the present invention will be described below with reference to the drawings. The laser ablation device  10  of this embodiment radiates laser light from an insertion portion, to be described later, onto affected tissue to cauterize the affected tissue, thereby performing treatment for arrhythmia etc., and includes an insertion portion  11  and a main portion  12 . 
         [0028]    As shown in  FIGS. 1 and 2 , the insertion portion  11  to be inserted into the body of patients is a long bendable pipe conduit and includes a fiber  15  that guides laser light emitted from a light source, to be described later, and that radiates the laser light from an insertion-portion distal end and a motor  16  that is provided on the fiber  15  to vibrate the fiber  15  with a predetermined period. Specifically, the fiber  15  is provided integrally with a shaft  16 A of the motor  16  and guides laser light while rotating in conjunction with rotation of the motor  16 . 
         [0029]    Specifically, the shaft  16 A has a hollow structure, and the fiber  15  passes through the shaft  16 A. The shaft  16 A of the motor  16  has a bent portion, so that the output of the motor  16  is made to be eccentric with respect to the axis of rotation. As shown in  FIG. 2C , four ball bearings  16 B are disposed in a distal end of the shaft  16 A at equal-spaced intervals, the fiber  15  is in contact with the shaft  16 A via the ball bearings  16 B, and thus the fiber  15  is fixed to the shaft  16 A. A lens  15 A through which laser light emitted from an emitting end of the fiber  15  is transmitted is provided on a distal end surface of the insertion portion  11 . 
         [0030]    The main portion  12  includes a light source section  17 , a vibration control section  18  that controls the vibration of the fiber  15 , and a control section  19  that controls the light source section  17  and the vibration control section  18 . 
         [0031]    The light source section  17  includes an LD (laser diode)  17 A that serves as the light source, which emits laser light for cauterizing an affected area, and an LD driving part  17 B that drives the LD  17 A. 
         [0032]    The vibration control section  18  has a motor driving part  18 A that rotationally drives the motor  16  and a rotating-speed modulating part  18 B that appropriately modulates the rotating speed of the motor  16 . 
         [0033]    The operation of the thus-configured laser ablation device  10  will be described below. 
         [0034]    The distal end of the insertion portion  11  of the laser ablation device  10  is inserted up to the vicinity of an affected area. In this state, when power is supplied from the LD driving part  17 B to the LD  17 A based on a control signal sent from the control section  19 , laser light is emitted from the LD  17 A and enters an incident end of the fiber  15  that is located at a base end of the insertion portion  11 . The laser light is guided by the fiber  15  to the distal end of the fiber  15  and is radiated from the emitting end of the fiber  15  onto the affected area via the lens  15 A, which is provided at the distal end of the insertion portion  11 . 
         [0035]    At this time, the fiber  15  is provided integrally with the shaft  16 A of the motor  16  so as to guide the laser light while rotating in conjunction with rotation of the motor  16 . Furthermore, because the shaft  16 A of the motor  16  makes the output of the motor  16  eccentric with respect to the axis of rotation, when the motor  16  is rotationally driven by the motor driving part  18 A, the laser light emitted from the fiber  15  is radiated onto the affected area while tracing a circular trajectory corresponding to the eccentric position of the shaft  16 A. 
         [0036]    As described above, according to this embodiment, rotation of the motor  16  vibrates the fiber  15 , which emits laser light, thereby making it also possible to vibrate the laser-light radiation trajectory, thus preventing laser light from being locally radiated onto the affected area and allowing uniform laser-light radiation while expanding the radiation region. 
       Second Embodiment 
       [0037]    Next, a laser ablation device  30  according to a second embodiment of the present invention will be described below with reference to the drawings. In this embodiment, identical reference signs are assigned to the same components as those in the above-described first embodiment, and a description thereof will be omitted. This embodiment mainly differs from the first embodiment in that piezoelectric elements  15 B are provided symmetrically in four directions around the axis of the output end of the shaft  16 A, as shown in  FIG. 3 . 
         [0038]    Therefore, the main portion  12  further includes a piezoelectric-element control section  20  that controls the piezoelectric elements, and the control section  19  controls the light source section  17 , the vibration control section  18 , and the piezoelectric-element control section  20 . 
         [0039]    The piezoelectric-element control section  20  includes an AM modulation part  23  that supplies electric power to the piezoelectric elements  15 B, a PLL control part  24  that adjusts the phases of modulated signals output from the AM modulation part  23  and the number of rotations of the motor  16 , an AC-signal generating part  21  that generates AC signals to be supplied to the AM modulation part  23 , and an amplification part  22  that amplifies the AC signals output from the AC-signal generating part  21 . 
         [0040]    As shown in  FIGS. 4A to 4D , the fiber  15  is provided in the hollow shaft  16 A, and the distal end of the fiber  15  is fixed to the shaft  16 A by ball bearings  16 B that are provided via an elastic member  16 C. Contact points of the ball bearings  16 B are located at the position of a node of a vibration of the elastic member. Because the piezoelectric elements  15 B are provided symmetrically in four directions around the axis of the fiber  15  via the elastic member  16 C and are composed of X-axis-driving piezoelectric elements and Y-axis-driving piezoelectric elements, the phases of the AC signals supplied from the AC-signal generating part  21  to the X-axis-driving piezoelectric elements and the Y-axis-driving piezoelectric elements are shifted by 90 degrees. 
         [0041]    Furthermore, the modulated signals output from the AM modulation part  23  and the rotating speed of the motor  16  are individually controlled by the PLL control part  24  so as to establish a relationship between frequency division and multiplication. 
         [0042]    The operation of the thus-configured laser ablation device will now be described. 
         [0043]    AC signals generated by the AC-signal generating part  21  are amplified by the amplification part  22  and are AM-modulated at the AM modulation part  23 . The frequencies of the voltage and the current to be applied to the piezoelectric elements  15 B are made to match the resonance frequency of a vibration of the fiber  15 . When the modulated signals output from the AM modulation part  23  are supplied to the piezoelectric elements  15 B, the piezoelectric elements  15 B vibrate due to the piezoelectric effect, thus vibrating the shaft  16 A. The vibration is transferred to make the fiber  15  resonate. 
         [0044]    In this state, when the LD driving part  17 B supplies predetermined power to the LD  17 A based on a control signal of the control section  19 , the LD  17 A emits laser light toward the emitting end of the fiber  15 . The emitted laser light is radiated onto an affected area from the insertion-portion distal end via the fiber  15 . 
         [0045]    At this time, as described above, because the motor  16  is driven, thereby rotating the shaft  16 A, and the piezoelectric elements  15 B vibrate due to the piezoelectric effect, thereby vibrating the distal end of the shaft  16 A, light radiated from the distal end of the insertion portion  11  traces a radiation trajectory obtained by superposing a vibration produced by the motor and a vibration produced by the piezoelectric elements  15 B. 
         [0046]      FIGS. 5A and 5B  show example laser-light radiation trajectories produced by the fiber  15 .  FIG. 5A  shows an example radiation trajectory in the case where, by setting the amplitude of a vibration produced by the piezoelectric elements  15 B smaller than the amplitude of a vibration produced by the motor  16 , the motor  16  roughly moves the laser light at the same time as the piezoelectric elements  15 B finely move the laser light.  FIG. 5A  shows an example laser-light radiation trajectory in the case where the piezoelectric elements  15 B vibrate the fiber  15  in a spiral pattern, and  FIG. 5B  shows an example laser-light radiation trajectory in the case where the piezoelectric elements  15 B vibrate the fiber  15  in a circular trajectory. 
         [0047]    In this way, according to this embodiment, by superposing the vibration produced by rotational motion of the motor  16  and the vibration produced by the piezoelectric elements  15 B, it is possible to prevent the laser light from being locally radiated and also to allow more uniform laser-light radiation, which prevents damage to tissue other than the affected area. Because it is possible to avoid fixed-point radiation and to allow area radiation, the therapeutic dose can be visually perceived with observation optics, such as an endoscope. 
         [0048]    Note that the number of rotations, the rotating speed, and the direction of rotation of the motor may be desirably set, and the amplitude of the motor may be different from or may be the same as the amplitude of the piezoelectric elements. Furthermore, in this embodiment, although a description has been given of a case in which the frequencies of the voltage and the current to be applied to the piezoelectric elements  15 B are made to match the resonance frequency of the vibration of the fiber  15 , the frequencies are not necessarily resonant and may be non-resonant. 
       Third Embodiment 
       [0049]    Next, a laser ablation device  40  according to a third embodiment of the present invention will be described with reference to the drawings. In this embodiment, identical reference signs are assigned to the same components as those in the above-described second embodiment, and a description thereof will be omitted. This embodiment mainly differs from the second embodiment in that piezoelectric elements  15 C are provided instead of the motor  16 , as shown in  FIGS. 6 and 7 . 
         [0050]    Specifically, the fiber  15  is provided with an elastic member  32  for supporting the piezoelectric elements  15 B and the piezoelectric elements  15 C. The piezoelectric elements  15 B are provided symmetrically in four directions at a distal end of the elastic member  32 , and the piezoelectric elements  15 C are provided symmetrically in four directions at a base end thereof. 
         [0051]    Therefore, the main portion  12  includes, instead of the piezoelectric-element control section  20 , a piezoelectric-element control section  28  that controls the piezoelectric elements  15 B and the piezoelectric elements  15 C. 
         [0052]    The piezoelectric-element control section  28  includes AM modulation parts  23 B and  23 C that supply electric power to the piezoelectric elements  15 B and  15 C, respectively, a PLL control part  24  that individually adjusts the phases of modulated signals output from the AM modulation parts  23 B and  23 C, AC-signal generating parts  21 B and  21 C that generate AC signals to be supplied to the AM modulation parts  23 B and  23 C, and amplification parts  22 B and  22 C that amplify the AC signals output from the AC-signal generating parts  21 B and  21 C. 
         [0053]    AC signals generated by the AC-signal generating part  21 B are amplified at the amplification part  22 B and are AM-modulated at the AM modulation part  23 B. Similarly, AC signals generated by the AC-signal generating part  21 C are amplified at the amplification part  22 C and are AM-modulated at the AM modulation part  23 C. Although the modulated signals output from the AM modulation part  23 B and the AM modulation part  23 C have different frequencies, they are controlled at the PLL control part  24  so as to establish a relationship between frequency division and multiplication. Furthermore, the frequencies of the voltage and the current to be applied to the piezoelectric elements  15 B are made to match the resonance frequency at the distal end portion of the elastic member  32 , and the frequencies of the voltage and the current to be applied to the piezoelectric elements  15 C are made to match the resonance frequency of the fiber  15 . 
         [0054]    The operation of the thus-configured laser ablation device will now be described. Modulated signals output from the AM modulation part  23 B and the AM modulation part  23 C are supplied to the piezoelectric elements  15 B and  15 C, respectively, and the piezoelectric elements  15 B and  15 C vibrate due to the piezoelectric effect based on the modulated signals. The vibrations are transferred via the elastic member  32  to vibrate the fiber  15 . 
         [0055]    In this state, when the LD driving part  17 B supplies predetermined power to the LD  17 A based on a control signal output from the control section  19 , the LD  17 A emits laser light toward the incident end of the fiber  15 . The emitted laser light is emitted from the distal end of the insertion portion  11  via the fiber  15 . 
         [0056]    At this time, because the piezoelectric elements  15 B and  15 C vibrate the fiber  15 , the laser light emitted from the distal end of the insertion portion  11  traces a radiation trajectory obtained by superposing a vibration produced by the piezoelectric elements  15 B and a vibration produced by the piezoelectric elements  150 . 
         [0057]      FIGS. 8A to 80  show example laser-light radiation trajectories produced by the fiber  15 .  FIGS. 8A to 8C  show example radiation trajectories in the case where, by setting the amplitude of a vibration produced by the piezoelectric elements  15 B smaller than the amplitude of a vibration produced by the piezoelectric elements  15 C, the piezoelectric elements  15 C roughly move the laser light at the same time as the piezoelectric elements  15 B finely move the laser light.  FIG. 8A  shows an example laser-light radiation trajectory in the case where the piezoelectric elements  15 B vibrate the fiber  15  in a spiral pattern at the same time as the piezoelectric elements  15 C vibrate the fiber  15  in a circular trajectory, and  FIG. 8B  shows an example laser-light radiation trajectory in the case where the piezoelectric elements  15 B vibrate the fiber  15  in the same way as in  FIG. 8A , and the piezoelectric elements  15 C vibrate the fiber  15  in a spiral pattern.  FIG. 8C  shows an example laser-light radiation trajectory in the case where both the piezoelectric elements  15 B and  15 C vibrate the fiber  15  in a circular trajectory. 
         [0058]    In this way, according to this embodiment, the vibration produced by the piezoelectric elements  15 B and the vibration produced by the piezoelectric elements  15 C are transferred to the fiber  15  via the elastic member  32 , and the vibration produced by the piezoelectric elements  15 B and the vibration produced by the piezoelectric elements  15 C are superposed, thereby making it possible to prevent the laser light from being locally radiated and also to allow more uniform laser-light radiation, which prevents damage to tissue other than the affected area. Because it is possible to avoid fixed-point radiation and to allow area radiation, the therapeutic dose can be visually perceived with observation optics, such as an endoscope. Because the variable range of the radiation region is wide, it is possible to respond flexibly to different treatment regions. 
       Modification of Third Embodiment 
       [0059]    Next, a laser ablation device according to a modification of the third embodiment of the present invention will be described with reference to the drawings. In this modification, identical reference signs are assigned to the same components as those in the above-described third embodiment, and a description thereof will be omitted. This embodiment mainly differs from the third embodiment in that a so-called three-stage structure in which piezoelectric elements are provided at three places in the axial direction of the elastic member  32  is built, as shown in  FIG. 9 . 
         [0060]    Specifically, the fiber  15  is provided with an elastic member  32  for supporting the piezoelectric elements  15 B, the piezoelectric elements  15 C, and piezoelectric elements  15 D. The elastic member  32  has the piezoelectric elements  15 B provided symmetrically in four directions at the distal end, the piezoelectric elements  15 C provided symmetrically in four directions closer to the base end than the piezoelectric elements  15 B, and the piezoelectric elements  15 D provided symmetrically in four directions at the base end. 
         [0061]    Therefore, as in the above-described third embodiment, the main portion includes, instead of the piezoelectric-element control section  20 , a piezoelectric-element control section  28  that controls the piezoelectric elements  15 B, the piezoelectric elements  15 C, and the piezoelectric elements  15 D, and the piezoelectric-element control section  28  includes AM modulation parts that supply electric power to the piezoelectric elements  15 B,  15 C, and  15 D, a PLL control part that individually adjusts the phases of modulated signals output from the AM modulation parts, AC-signal generating parts that generate AC signals to be supplied to the AM modulation parts, and amplification parts that amplify the AC signals output from the AC-signal generating parts. 
         [0062]      FIGS. 10A to 10C  show example laser-light radiation trajectories produced by the fiber  15  in the case where the piezoelectric elements  15 B,  15 C, and  15 D are provided at three places in the axial direction of the fiber, as described above.  FIGS. 10A to 10C  show example radiation trajectories in the case where, by setting the amplitude of a vibration produced by the piezoelectric elements that are provided closer to the distal end of the fiber  15  to be smaller, the piezoelectric elements that are provided closer to the base end roughly move the laser light at the same time as the piezoelectric elements that are provided closer to the distal end finely move the laser light. In particular,  FIG. 10A  shows an example laser-light radiation trajectory in the case where the piezoelectric elements  15 B vibrate the fiber  15  in a spiral pattern at the same time as the piezoelectric elements  15 C and  15 D vibrate the fiber  15  in a circular trajectory.  FIG. 10B  shows an example laser-light radiation trajectory in the case where the piezoelectric elements  15 D vibrate the fiber  15  in a circular trajectory at the same time as the piezoelectric elements  15 B and  15 C vibrate the fiber  15  in a spiral pattern.  FIG. 10C  shows an example laser-light radiation trajectory in the case where all of the piezoelectric elements  15 B,  15 C, and  15 D vibrate the fiber  15  in a circular trajectory. 
         [0063]    In this way, according to this embodiment, the vibrations produced by the piezoelectric elements  15 B,  15 C, and  15 D are transferred to the fiber  15  via the elastic member  32 , and the vibrations produced by the piezoelectric elements  15 B,  15 C, and  15 D are superposed, thereby making it possible to prevent the laser light from being locally radiated and also to allow more uniform laser-light radiation, which prevents damage to tissue other than the affected area. Because it is possible to avoid fixed-point radiation and to allow area radiation, the therapeutic dose can be visually perceived with observation optics, such as an endoscope. Because the variable range of the radiation region is wide, it is possible to respond flexibly to different treatment regions. 
         [0064]    Note that, in the above-described embodiments, although piezoelectric elements are used as a means for producing a vibration, such means is not necessarily limited to the piezoelectric elements and can be electromagnetic vibration elements, for example. 
         [0065]    Furthermore, although the third embodiment is provided with a two-stage structure that has a drive unit in which the piezoelectric elements  15 B produce a vibration and a drive unit in which the piezoelectric elements  15 C produce a vibration, and the modification of the third embodiment is provided with a three-stage structure that has three drive units in each of which the piezoelectric elements produce a vibration, a structure having four or more stages may be provided, and every possible means that can vibrate the fiber, such as motors, piezoelectric elements, and electromagnetic vibration elements, can be used alone or in appropriate combinations, as drive units. 
         [0066]    For example, as shown in  FIGS. 11A and 11B , an electromagnetic vibration element  35  has a permanent magnet  33  that is disposed on the axis of the elastic member  32 , which transfers a vibration to the fiber  15 , and a coil  34  that is provided so as to surround the permanent magnet  33 . When the thus-configured electromagnetic vibration element  35  is used, it is possible to build a structure in which the electromagnetic vibration element  35  is provided closer to the base end of the fiber  15 , and the piezoelectric elements  15 C are provided closer to the distal end thereof, as shown in  FIG. 11A , or a structure in which the electromagnetic vibration element  35  is provided closer to the base end of the fiber  15  and also closer to the distal end thereof, as shown in  FIG. 11B . 
         [0067]    Then, when current is supplied to the coil, the permanent magnet vibrates due to electromagnetic induction, and this vibration vibrates the distal end of the fiber  15  via the elastic member. Because the electromagnetic vibration element  35  can perform raster scanning, when the piezoelectric elements are provided closer to the distal end of the fiber  15 , as shown in  FIG. 11A , the raster scanning can be combined with a vibration produced by rotation of the piezoelectric elements, as shown in  FIGS. 12A and 12B . Furthermore, when the electromagnetic vibration element  35  is provided closer to the base end of the fiber  15  and also closer to the distal end thereof, as shown in  FIG. 11B , if both of the electromagnetic vibration elements  35  perform raster scanning, a scan trajectory shown in  FIG. 12C  can be obtained. In either case, laser light can be prevented from being locally radiated. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           10 ,  30 ,  40  laser ablation device 
           11  insertion portion 
           15  fiber 
           15 B piezoelectric elements 
           15 C piezoelectric elements 
           16  motor 
           16 A shaft 
           17 A light source 
           18  vibration control section 
           19  control section 
           20 ,  28  piezoelectric-element control section