Patent Publication Number: US-2021177520-A1

Title: Calibration device for surgical instruments

Description:
FIELD OF THE INVENTION 
     This invention generally relates to a calibration device, and more particularly to a calibration device used to calibrate coordinates of surgical instruments. 
     BACKGROUND OF THE INVENTION 
     Surgical navigation system is a necessary auxiliary system for minimally invasive surgeries (brain surgery, vertebrae surgery and abdominal puncture). Before surgery, positioning of navigation system and surgical instruments, such as surgical probe and bone access needle, is required for obtaining surgical instrument coordinate in the surgical navigation system. 
     China Patent Application No. 201410396220.0 (Publication No. CN 104146773 A) disclosed a calibration block used for calibrating surgical instruments. However, calibration error may be caused due to the calibration block is unavailable for calibrating six degrees of freedom and straightness of surgical instruments. Accuracy and precision in conventional surgical navigation system have to be improved. 
     SUMMARY 
     One object of the present invention is to utilize an instrument holder pivotally mounted on a base to allow a surgical instrument inserted into the instrument holder to selectively rotate or swing for calibrating six degrees of freedom and straightness of the surgical instrument. 
     A calibration device of the present invention includes a base, an instrument holder and at least one reference frame marker, the instrument holder is pivotally mounted on the base and includes at least one insertion hole, the at least one insertion hole is provided for insertion of a surgical instrument such that the surgical instrument is able to be rotated or swung selectively on the base, the reference frame marker is mounted on the base. 
     Because of the instrument holder pivotally mounted on the base, the surgical instrument inserted into the instrument holder can be rotated or swung selectively on the base, consequently, a signal processor can receive coordinate signals from the reference frame marker mounted on the base and at least one coordinate marker mounted on the surgical instrument for calibrating the surgical instrument. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective assembly diagram illustrating a calibration device in accordance with a first embodiment of the present invention and a surgical instrument. 
         FIG. 2  is a perspective explored diagram illustrating the calibration device in accordance with the first embodiment of the present invention. 
         FIG. 3  is a cross-section view diagram illustrating the calibration device in accordance with the first embodiment of the present invention. 
         FIG. 4  is a perspective assembly diagram illustrating insertion of a surgical instrument with the calibration device in accordance with the first embodiment of the present invention. 
         FIG. 5  is a perspective assembly diagram illustrating a calibration device in accordance with a second embodiment of the present invention. 
         FIG. 6  is a partial perspective assembly diagram illustrating the calibration device in accordance with the second embodiment of the present invention. 
         FIG. 7  is a perspective explored diagram illustrating the calibration device in accordance with the second embodiment of the present invention. 
         FIG. 8  is a cross-section view diagram illustrating the calibration device in accordance with the second embodiment of the present invention. 
         FIG. 9  is a cross-section view diagram illustrating the calibration device in accordance with the second embodiment of the present invention. 
         FIG. 10  is a cross-section view diagram illustrating the calibration device in accordance with the second embodiment of the present invention. 
         FIG. 11  is a perspective explored diagram illustrating a calibration device in accordance with a third embodiment of the present invention. 
         FIG. 12  is a cross-section view diagram illustrating the calibration device in accordance with the third embodiment of the present invention. 
         FIG. 13  is a perspective assembly diagram illustrating a calibration device in accordance with a fourth embodiment of the present invention. 
         FIG. 14  is a partial perspective assembly diagram illustrating the calibration device in accordance with the fourth embodiment of the present invention. 
         FIG. 15  is a perspective explored diagram illustrating the calibration device in accordance with the fourth embodiment of the present invention. 
         FIG. 16  is a cross-section view diagram illustrating the calibration device in accordance with the fourth embodiment of the present invention. 
         FIG. 17  is a cross-section view diagram illustrating the calibration device in accordance with the fourth embodiment of the present invention. 
         FIG. 18  is a cross-section view diagram illustrating the calibration device in accordance with the fourth embodiment of the present invention. 
         FIG. 19  is a perspective explored diagram illustrating a calibration device in accordance with a fifth embodiment of the present invention. 
         FIG. 20  is a cross-section view diagram illustrating the calibration device in accordance with the fifth embodiment of the present invention. 
         FIG. 21  is a perspective explored diagram illustrating a calibration device in accordance with a sixth embodiment of the present invention. 
         FIG. 22  is a cross-section view diagram illustration the calibration device in accordance with the sixth embodiment of the present invention. 
         FIG. 23  is a cross-section view diagram illustrating a calibration device in accordance with a seventh embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to  FIGS. 1 to 23 , a calibration device  100  is provided for coordinate calibration of a surgical instrument  200 , such as surgical probe or bone access needle. The calibration device  100  includes a base  110 , an instrument holder  120  and at least one reference frame marker  130 . The reference frame marker  130  is mounted on the base  110 , and the instrument holder  120  is pivotally mounted on the base  110 , as a result, the instrument holder  120  can rotate or swing selectively relative to the base  110 . There is at least one insertion hole  122   a  formed on the instrument holder  120 , and the surgical instrument  200  is able to be inserted into the insertion hole  122   a  and able to be rotated or swung selectively with the instrument holder  120  on the base  110 . At least one coordinate marker  210  is mounted on the surgical instrument  200  to be moved with the surgical instrument  200 . The reference frame marker  130  and the coordinate marker  210  are, but not limited to, image sensors or radio frequency components. 
     The calibration device  100  of a first embodiment of the present invention is shown in  FIGS. 1 to 4 . The instrument holder  120  is pivotally mounted in a first accommodation groove  111  of the base  110 , and in the first embodiment, the instrument holder  120  includes a pivot portion  121  and an insertion portion  122 . The pivot portion  121  is pivotally located in the first accommodation groove  111  so the instrument holder  120  is rotatable or swingable, and the pivot portion  121  and the insertion portion  122  are connected to one another and movable together. The insertion hole  122   a  is located on the insertion portion  122  and is revealed by the first accommodation grove  111 . 
     With reference to  FIGS. 1 to 4 , the base  110  of the first embodiment includes a grip portion  110   a , a pivot portion  110   b  and a marker mounting portion  110   c . As shown in  FIGS. 2 and 3 , the grip portion  110   a  is provided for user to grip, the pivot portion  110   b  is coupled to the grip portion  110   a , and an included angle A exists between the pivot portion  110   b  and the grip portion  110   a , the first accommodation groove  111  is recessed on the pivot portion  110   b , the reference frame marker  130  is mounted on the marker mounting portion  110   c . With reference to  FIG. 3 , in the first embodiment, the instrument holder  120  is a spheroid, an axis X passes through a center O 1  of the insertion hole  122   a  and a center of gravity O 2  of the instrument holder  120 , and the center of gravity O 2  is located on a hole bottom surface F of the insertion hole  122   a . Preferably, there are multiple insertion holes  122   a  on the insertion portion  122 , each of the insertion holes  122   a  has a diameter different to one another for insertion of surgical instruments  200  having different outer diameters. If the insertion portion  122  has multiple insertion holes  122   a , there are multiple axes X which each passes through center O 1  of each of the insertion holes  122   a  and the center of gravity O 2  of the instrument holder  120 , further, the center of gravity O 2  is located on hole bottom surface F of each of the insertion holes  122   a  such that terminals of the surgical instruments  200  inserted into different insertion holes  122   a  all can align the center of gravity O 2 . 
     With reference to  FIG. 4 , after inserting the surgical instrument  200  into the insertion hole  122   a , a signal processor  300  is provided to receive a first coordinate signal of the reference frame marker  130  mounted on the base  110  and a second coordinate signal of the coordinate marker  210  mounted on the surgical instrument  200  for calibrating a straightness of the surgical instrument  200 . And then when the surgical instrument  200  is moved (swung or rotated), the signal processor  300  is provided to receive the second coordinate signal after moving to calibrate the degrees of freedom of the surgical instrument  200  in 3D space. 
     With reference to  FIG. 1 to 3 , the calibration device  100  preferably further includes a restriction lid  140  which has an exposure hole  141  communicating with the first accommodation groove  111 . The restriction lid  140  is configured to cover the pivot portion  121  to cage the pivot portion  121  between the first accommodation groove  111  and the restriction lid  140 , and the insertion hole  122   a  is exposed by the exposure hole  141 . In the first embodiment, the restriction lid  140  is provided to contact the pivot portion  121  to prevent improper rotation of the instrument holder  120 . 
       FIGS. 5 to 10  are diagrams illustrating a calibration device  100  of a second embodiment of the present invention. The insertion portion  122  and the pivot portion  121  of the second embodiment are different to those of the first embodiment. With reference to  FIGS. 6 to 9 , in the second embodiment, the insertion portion  122  includes a plurality of grippers  122   b  and a sleeve  122   c , and the pivot portion  121  includes a body  121   a  and a screw post  121   b . The sleeve  122   c  includes an opening  122   d , an accommodation space  122   e  and a conical inner wall  122   f , the opening  122   d  communicates with the accommodation space  122   e , and the conical inner wall  122   f  surrounds around the accommodation space  122   e . The body  121   a  has a second accommodation groove  121   c , and the screw post  121   b  is located in the second accommodation groove  121   c . The sleeve  122   c  is screwed with the screw post  121   b , the grippers  122   b  are placed in the accommodation space  122   e  and surround around the insertion hole  122   a , and the conical inner wall  122   f  of the sleeve  122   c  contacts the grippers  122   b . Preferably, each of the grippers  122   b  has an elastic element  123 . With reference to  FIGS. 7 and 9 , the sleeve  122   c  can be rotated to change the screwing position relative to the screw post  121   b  and further change the diameter of the insertion hole  122   a . Consequently, the insertion hole  122   a  with adjustable diameter is suitable for different surgical instruments  200 . With reference to  FIGS. 7 and 9 , in order to enlarge the diameter of the insertion hole  122   a , the sleeve  122   c  screwed with the screw post  121   b  can be rotated up to allow the elastic elements  123  to push the grippers  122   b  to touch the conical inner wall  122   f . In contrast, the diameter of the insertion hole  122   a  can be reduced by rotating the sleeve  122   c  screwed with the screw post  121   b  down to allow the conical inner wall  122   f  to contact the grippers  122   b . In the second embodiment, the diameter of the insertion hole  122   a  can be adjusted by rotating the sleeve  122   c  up or down to change the screwing position of the sleeve  122   c  on the screw post  121   b , as a result, the grippers  122   b  can be used to grip different surgical instruments  200 . 
     With reference to  FIGS. 5 to 10 , the calibration device  100  further includes a release mechanism  150  in the second embodiment. The release mechanism  150  is provided to allow the restriction lid  140  not to touch the instrument holder  120  such that the instrument holder  120  can be rotated or swung freely. With reference to  FIGS. 6 and 7 , the release mechanism  150  includes a beam  151 , at least one transmission rod  152  and a lever  153 . With reference to  FIGS. 5, 7 and 9 , the base  110  has a first space  110   d  and a second space  110   e  which communicate with each other, the beam  151  is set in the first space  110   d , and the lever  153  is set in the second space  110   e . With reference to  FIGS. 7 and 8 , the transmission rod  152  is movably located in a through hole  110   h  of the pivot portion  110   b , one end of the transmission rod  152  is connected to the beam  151  and the other end of the transmission rod  152  is connected to the restriction lid  140 . The lever  153  is pivotally mounted in the second space  110   e  by a pivot  154  and includes a pushing end  153   a  and a pressed end  153   b , the pushing end  153   a  is located in the first space  110   d  and under the beam  151 , the pressed end  153   b  protrudes from the second space  110   e.    
     With reference to  FIG. 10 , while the pressed end  153   b  is pressed down, the pushing end  153   a  is provided to push the beam  151  to allow the beam  151 , the transmission rod  152  and the restriction lid  140  to move toward a first direction together and allow the restriction lid  140  to release the pivot portion  121  such that the instrument holder  120  is free to rotate or swing in the absence of the restriction lid  140 . 
     With reference to  FIGS. 5 to 10 , preferably, the release mechanism  150  further includes at least one elastic element  155 , and both ends of the elastic element  155  are fixed on the base  110  and the beam  151 , respectively. As shown in  FIGS. 9 and 10 , when no external force acts on the pressed end  153   b , the elastic element  155  is configured to pull the beam  151  such that the beam  151 , the transmission rod  152  and the restriction lid  140  are moved toward a second direction opposite to the first direction to allow the restriction lid  140  to contact the pivot portion  121 . In the second embodiment, the release mechanism  150  further includes a positioning element  156  which is mounted in the base  110  to fix the elastic element  155  in the base  110 . 
     A calibration device  100  of a third embodiment of the present invention is shown in  FIGS. 11 and 12 . The instrument holder  120  is a spheroid in the third embodiment, different to the instrument holder  120  of the second embodiment. In the third embodiment, the release mechanism  150  is also provided to allow the restriction lid  140  to block the pivot portion  121  or allow the restriction lid  140  to unblock the pivot portion  121  by pressing the lever  153 . 
       FIGS. 13 to 18  illustrate a calibration device  100  in accordance with a fourth embodiment of the present invention. The base  110  and the release mechanism  150  of the fourth embodiment are different to that of the second embodiment. With reference to  FIGS. 15 and 17 , in the fourth embodiment, the base  110  includes a restriction hole  110   f  communicating with the first space  110   d , and the release mechanism  15  includes a linkage rod  157  and an elastic element  158 . As shown in  FIG. 17 , there is a restriction bulge  110   g  in the restriction hole  110   f , the linkage rod  157  of the release mechanism  150  is movably placed in the restriction hole  110   f  a first end  157   a  of the linkage rod  157  is coupled to the beam  151 , a second end  157   b  of the linkage rod  157  is restricted in the restriction hole  110   f  and both ends of the elastic element  158  touch the second end  157   b  of the linkage rod  157  and the restriction bulge  110   g , respectively. 
     With reference to  FIG. 18 , when pressing down the pressed end  153   b , the pushing end  153   a  pushes the beam  151  to move the beam  151 , the transmission rod  152 , the restriction lid  140  and the linkage rod  157  together toward a first direction, as a result, the pivot portion  121  is not locked by the restriction lid  140  and the instrument holder  120  can be rotated or swung freely. Further, the elastic element  158  is compressed by the second end  157   b  of the linkage rod  157  to have a return force when the pressed end  153   b  is pressed down. With reference to  FIG. 17 , the compressed elastic element  158  is configured to push the second end  157   b  of the linkage rod  157  when no external force acts on the pressed end  153   b  of the lever  153  so that the beam  151 , the transmission rod  152 , the restriction lid  140  and the linkage rod  157  are moved together toward a second direction opposite to the first direction, and the restriction lid  140  is moved to contact the pivot portion  121  to prevent the instrument holder  120  from rotating. 
     With reference to  FIGS. 19 and 20 , a calibration device  100  of a fifth embodiment of the present invention is disclosed. The difference between the fourth and fifth embodiments is that the instrument holder  120  of the fifth embodiment is a spheroid. In the fifth embodiment, the pivot portion  121  is also be blocked by or unblocked from the restriction lid  140  with the aid of the release mechanism  150 . 
     A calibration device  100  of a sixth embodiment of the present invention is disclosed in  FIGS. 21 and 22 . Different to the second embodiment, the release mechanism  150  of the sixth embodiment further includes a blocker  159  which is a bolt movably mounted on the base  110 . A terminal  159   a  of the blocker  159  is used to contact the instrument holder  120  to prevent undesired rotation of the instrument holder  120 . 
     With reference to  FIG. 22 , when the blocker  159  is screwed toward the instrument holder  120  to allow the terminal  159   a  to contact the instrument holder  120 , the instrument holder  120  cannot be moved. Reversely, the instrument holder  120  is free to rotate or swing when the blocker  159  is screwed away from the instrument holder  120  to allow the terminal  159   a  not to contact the instrument holder  120 . 
       FIG. 23  shows a calibration device  100  of a seventh embodiment of the present invention. The difference between the sixth and seventh embodiments is that the instrument holder  120  is a spheroid in the seventh embodiment. The instrument holder  120  of the seventh embodiment is also prevented from undesired rotation by the blocker  159  and able to be rotated or swung freely when the blocker  159  is moved away from the instrument holder  120 . 
     While this invention has been particularly illustrated and described in detail with respect to the preferred embodiments thereof, it will be clearly understood by those skilled in the art that is not limited to the specific features shown and described and various modified and changed in form and details may be made without departing from the spirit and scope of this invention.