TREA

Instrument guide

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Information

  • Patent Grant
  • 6726699
  • Patent Number
    6,726,699
  • Date Filed
    Tuesday, August 15, 2000
    24 years ago
  • Date Issued
    Tuesday, April 27, 2004
    20 years ago
Information
Abstract
An instrument guide that can compensate for surgical instruments that have different outer diameters. The instrument guide includes a shaft that has an inner channel adapted to receive a surgical instrument. The guide also has a leaf that can be deflected relative to the shaft to exert a spring force onto the instrument. The amount of leaf deflection is dependent upon the outer diameter of the surgical instrument.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to an instrument guide for guiding a surgical instrument into a patient.




2. Prior Art




There have been developed various procedures to perform minimally invasive surgery. For example, there have been developed minimally invasive procedures to perform a coronary artery bypass graft (CABG). The minimally invasive CABG procedure can be performed with a robotic system sold by Computer Motion, Inc., the assignee of the present invention, under the trademark ZEUS.




The ZEUS system includes a plurality of robotic arms that can control the movement of surgical instruments inserted through small incisions in the patient. The surgical instruments move in accordance with the movement of handles held by a surgeon. The handles are located at a console that allows the surgeon to view a monitor that is coupled to an endoscope inserted into the patient. The surgeon can perform a surgical procedure by moving the handles and viewing the surgical site displayed by the monitor.




Performing a minimally invasive procedure may require a number of different surgical instruments. Each robotic arm of the ZEUS system has a coupling mechanism that allows instruments to be attached to, and detached from, the arm. The surgeon, or a surgeon assistant can readily replace instruments during a procedure.




The instruments are typically inserted through a trocar that penetrates the body cavity of the patient. The ZEUS system utilizes the incision point of the patient as a pivot point for the robotic arm and the surgical instrument. The system utilizes a software routine that transforms the coordinates of the surgical instruments to stationary world coordinates to provide commands that accurately move the instruments.




An instrument guide may be placed within the trocar to guide the instrument, maintain robotic arm positioning and facilitate instrument exchanges during surgery. The inner diameter of the instrument guide has approximately the same diameter as the outer diameter of the surgical instrument to prevent relative radial movement between the instrument and the guide. Any excessive space between the surgical instrument and the instrument guide may result in a lag between the movement of the handles and the movement of the instrument. This lag may increase the complexity of performing the procedure.




The outer diameter of the surgical instruments may vary from instrument to instrument. Smaller surgical instruments may create an undesired space between the instrument and the guide. It would be desirable to provide an instrument guide that can be secured to a variety of surgical instruments each having a different outer diameter.




BRIEF SUMMARY OF THE INVENTION




One embodiment of the present invention is an instrument guide that can be inserted into a patient and guide a surgical instrument. The instrument guide includes a shaft that has an inner channel adapted to receive the surgical instrument. The guide also has a leaf that extends from the shaft. The leaf is adapted to move relative to the shaft when the surgical instrument is inserted into the inner channel.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an illustration of an embodiment of a robotic surgical system of the present invention;





FIG. 2

is a side view of an instrument guide tip of the robotic surgical system;





FIG. 3

is an illustration of the instrument guide used with a manually actuated surgical instrument.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




In general the present invention includes an instrument guide that can compensate for surgical instruments that have different outer diameters. The instrument guide includes a shaft that has an inner channel adapted to receive a surgical instrument. The guide also has a leaf that can be deflected relative to the shaft to exert a spring force onto the instrument. The amount of leaf deflection is dependent upon the outer diameter of the surgical instrument.




Referring to the drawings more particularly by reference numbers,

FIG. 1

shows an embodiment of a robotic surgical system


10


of the present invention. The system


10


may include a surgical instrument


12


that extends through a body cavity


14


of a patient. The instrument


12


may be coupled to a robotic arm


16


. The robotic arm


16


may include a number of active joints


18


that can be activated to move the instrument


12


relative to the patient. The arm


16


may also have one or more passive joints (not shown) that allow the instrument


12


to pivot about the incision point of the patient.




The surgical instrument


12


may be connected to a tool driver


20


that can both spin the instrument


12


and actuate an instrument end effector


22


. The tool driver


20


can be configured to allow an operator to readily connect and disconnect the instrument


12


from the driver


20


.




The robotic arm


16


and tool driver


20


can be actuated in accordance with the manipulation of handles (not shown) by the surgeon. Such a system may be the same or similar to a robotic system sold by Computer Motion, Inc. under the trademark ZEUS and disclosed in U.S. Pat. No. 6,007,550 issued to Wang et al., which are hereby incorporated by reference.




The surgical instrument


12


may extend through an instrument guide


24


. The instrument guide


24


may extend through a port element such as a trocar


26


that is inserted into the patient. The instrument guide


24


can be used to guide the instrument


12


through the trocar


26


. Although a trocar is shown and described, it is to be understood that the instrument guide


24


can be inserted through a cannula or other port element.




Referring to

FIG. 2

, the instrument guide


24


may include a guide tip


28


which has a plurality of leaves


30


that extend from a shaft


32


. By way of example, the guide tip


28


may have a plurality of leaves


30


. The shaft


32


may have an inner channel


34


that is adapted to receive the surgical instrument


12


. A proximal end of the tip


28


may have a bore


36


that can be pressed into an end of a tube


38


portion of the guide


24


that extends through the trocar


26


as shown in FIG.


1


. The guide tube


38


may be attached to the tool driver


20


.




Referring again to

FIG. 2

, the leaves


30


are separated by slots


40


. The slots


40


allow the leaves


30


to be deflected in an outward direction when the instrument


12


is inserted through the inner channel


34


. The amount of deflection is dependent upon the outer diameter of the surgical instrument


12


. The leaves


30


exert a spring force onto the surgical instrument


12


to prevent radial movement between the instrument


12


and the guide


24


. The deflecting leaves


30


compensate for various instrument outer diameters while securing the instrument at the pivot point of the system. Each leaf


30


may have an inner tapered portion


42


and a lip


44


configured to reduce the difficulty of retracting the instrument


12


from the guide


24


.




While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention is not limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.




For example, although the instrument guide


24


is shown inserted into a trocar and attached to a robotic arm, as shown in

FIG. 3

the guide


24


′ can be inserted into the body cavity


14


without a trocar. Additionally, the surgical instrument


12


′ may be a manually actuated device that is not attached to a robotic arm. In this embodiment the instrument guide


24


′ is configured as a trocar that can be inserted into a patent.



Claims
  • 1. An instrument guide that can be inserted into a patient and guide a surgical instrument that has a diameter, comprising:a shaft that has an inner channel; and, a plurality of leaves that extend from said shaft, said leaves being separated by a space having an inner diameter that is smaller than the diameter of the surgical instrument so that said leaves move when the surgical instrument is inserted into the inner channel, each leaf has a tapered portion and a lip.
  • 2. The instrument guide of claim 1, wherein said leaves are separated by a plurality of slots.
  • 3. The instrument guide of claim 1, wherein said leaves exert a spring force on the surgical instrument.
  • 4. An instrument guide assembly that can be inserted into a patient and support a surgical instrument that has a diameter, comprising:a port element that has an inner channel; and an instrument guide that can be inserted into said inner channel of said port element, said instrument guide having a shaft that has an inner channel, and a plurality of leaves that extend from said shaft, said leaves being separated by a space having an inner diameter that is smaller than the diameter of the surgical instrument so that said leaves move relative to said shaft when the surgical instrument is, inserted into the inner channel, each leaf has a tapered portion and a lip.
  • 5. The assembly of claim 4, wherein said leaves are separated by a plurality of slots.
  • 6. The assembly of claim 4, wherein said leaves exert a spring force on the surgical instrument.
  • 7. The assembly of claim 4, wherein said port element is a trocar.
  • 8. The assembly of claim 4, wherein said port element is a cannula.
  • 9. A trocar that can guide a surgical instrument that has a diameter, comprising:a shaft that has an inner channel and, a plurality of leaves that extend from said shaft, said leaves being separated by a space having an inner diameter that is smaller than the diameter of the surgical instrument so that said leaves move relative to said shaft when the surgical instrument is inserted into the inner channel, each leaf has a tapered portion and a lip.
  • 10. The trocar of claim 9, wherein said-leaves are separated by a plurality of slots.
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