The present invention generally relates to a relative tracking of a telescopic endoscope having a miniature secondary endoscope deployed within an instrument channel of a larger primary endoscope. The present invention specifically relates to an integrated tracking of both the primary and secondary endoscopes to minimize the position errors that may occur with an individual optical tracking of the miniature secondary endoscope.
Access to distal regions of the lung is often necessary to perform a biopsy. For endoscopic access to regions that are more distal than the fifth (5th) to sixth (6th) branchpoint of a bronchial tree, a miniature secondary may be used where the miniature secondary endoscope is typically deployed through the instrument channel of a larger primary endoscope. For example,
A significant problem faced by physicians with a miniature secondary endoscope is determining the position of the distal end of the miniature secondary endoscope in the bronchial tree relative to the known anatomy (e.g., anatomy imaged on a pre-procedural CT scan). Tracking the position of endoscopes in real-time is a solution to this problem. Prior art in endoscope tracking has been performed with several methods, including electromagnetic systems and optical fiber shape sensors (e.g., Fiber Bragg Gratings and Rayleigh scattering).
Optical fiber-based shape sensors have many advantages over other tracking methods like electromagnetic tracking. However, one limitation of optical fiber-based shape sensors is achieving high accuracy may be very challenging with very long, flexible probes, particularly those that allow for a significant amount of torsion. Specifically, position errors are known to accrue quadratically with length. Consequently, accurate position tracking of a flexible miniature secondary endoscope with optical fiber shape sensors is significantly more challenging than tracking a traditional primary endoscope that is larger and less flexible. For example, as shown in
The present invention provides a technique of simultaneously tracking a larger primary endoscope and a miniature secondary endoscope with optical fiber sensing, so that position errors that arise with individually tracking the miniature secondary endoscope may be minimized. Furthermore, a multi-core fiberscope may serve as the miniature secondary endoscope whereby individual pixel fibers of the multi-core fiberscope may be used for shape sensing interrogation using Rayleigh scatter reflection patterns.
For purposes of the present invention, the terms “primary” and “miniature secondary” are not intended to specify any particular dimensions of the devices being described by these terms. The actual use of the terms is to differentiate the relative dimensions of the devices being described by these terms.
One form of the present invention is a telescopic endoscope including a primary endoscope, miniature secondary endoscope and an endoscope tracker. The primary endoscope has an instrument channel, the miniature secondary endoscope is deployed within the instrument channel of the primary endoscope, and the endoscope tracker includes one or more sensors and one or more markers for sensing any portion of the miniature secondary endoscope extending from a distal end of the instrument channel of the primary endoscope.
A second form of the present invention is an optical tracking method involving a deployment of the miniature secondary endoscope within an instrument channel of the primary endoscope, and an operation of the endoscope tracker for sensing any portion of the miniature secondary endoscope extending from a distal end of the instrument channel of the primary endoscope.
The foregoing forms and other forms of the present invention as well as various features and advantages of the present invention will become further apparent from the following detailed description of various exemplary embodiments of the present invention read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the present invention rather than limiting, the scope of the present invention being defined by the appended claims and equivalents thereof
As shown in
As will be further explained herein in connection with the description of
In one embodiment, the markers are disposed at regular intervals along the length of miniature secondary endoscope 40 whereby sensors 32 count how many markers have passed by as the miniature secondary endoscope 40 is translated within primary endoscope 30 in either a proximal P direction (−) or a distal direction D (+) to thereby determine the extended portion of miniature secondary endoscope 40. Additionally, the markers at different angles are differently colored whereby an angle of miniature secondary endoscope 40 is sensed by how the differently-colored markings are oriented relative to the distal end D of the instrument channel of primary endoscope 30.
The telescopic endoscope of
As shown in
Again, as will be further explained herein in connection with the description of
In one embodiment, the sensors are disposed at regular intervals along the length of miniature secondary endoscope 60 whereby each sensor passing by multi-colored markers 52 as the miniature secondary endoscope 60 is translated within primary endoscope 50 in either a proximal P direction (−) or a distal direction D (+) is counted to thereby determine the extended portion of miniature secondary endoscope 50. Additionally, sensors at different angles may provide differing color filters whereby an angle of miniature secondary endoscope 60 is sensed by how the differing color filters are oriented relative to the distal end D of the instrument channel of primary endoscope 50.
The telescopic endoscope of
The tracking of an extended portion of a miniature secondary endoscope is based on an optical shape sensing of the miniature secondary endoscope, and an optical shape sensing or reference tracking of a primary endoscope as will be further explained in connection with the description of
For purposes of the present invention, the term “optical fiber” is broadly defined herein as any article or device structurally configured for transmitting/reflecting light by means of successive internal optical reflections via a deformation sensor array with each deformation optic sensor of array being broadly defined herein as any article structurally configured for reflecting a particular wavelength of light while transmitting all other wavelengths of light whereby the reflection wavelength may be shifted as a function of an external stimulus applied to the optical fiber. Examples of optical fiber include, but are not limited to, a flexible optically transparent glass or plastic fiber incorporating an array of fiber Bragg gratings integrated along a length of the fiber as known in the art, and a flexible optically transparent glass or plastic fiber having naturally variations in its optic refractive index occurring along a length of the fiber as known in the art (e.g., a Rayleigh scattering based optical fiber).
In practice, each optical fiber may include one or more fiber cores as known in the art, such as, for example, a multi-core embodiment of optical fiber 33 having a known helical arrangement of four (4) cores 34 as shown in
Referring back to
As shown in
In practice, the sensors and the markers of the secondary endoscope tracker may be based on any physical parameter suitable for sensing the extended portion of a miniature secondary endoscope. For example, the endoscope tracker may utilize an optical color sensing as previously described herein, a magnetic sensing, an electrical capacitance sensing, an impedance sensing, a field strength sensing, a frequency sensing, an acoustic sensing, a chemical sensing and other sensing techniques as well known in the art.
As description of an optical tracking system and method will now be provided herein to facilitate a further understanding of the present invention.
As shown in
Telescopic endoscope tracker 80 is broadly defined herein as any device or system structurally configured for executing a shape reconstruction algorithm for reconstructing a shape of optical fiber 83 and/or optical fiber 85 as will be further explained with the description of
Optical interrogation console 81 is broadly defined herein as any device or system structurally configured for transmitting light through optical fibers 83 and 85 for processing encoded optical signals of reflection spectrums generated by the successive internal reflections of the transmitted light via the deformation optic sensor arrays of optical fibers 83 and 85. In one embodiment, optical interrogation console 81 employs an arrangement (not shown) of a coherent optical source, a frequency domain reflectometer, and other appropriate electronics/devices as known in the art.
Sensor console 82 is broadly defined herein as any device or system structurally configured for executing a sensing algorithm appropriate for the sensing scheme being implemented by the secondary endoscope tracker of sensors and markers.
Collectively, telescopic endoscope tracker 80, an optical interrogation console 81 and a sensor console 82 implement a flowchart 90 (
Referring to
A stage S91 of flowchart 90 encompasses a determination of a position of a primary endoscope 84 within tracking coordinate system 100 of console 81, particularly a position of distal end of primary endoscope 84 within tracking coordinate system 100. Specifically, optical interrogation console 81 operates optical fiber 83 to thereby facilitate a reconstruction of a shape of primary endoscope 84 by telescopic endoscope tracker 80.
A stage S92 of flowchart 90 encompasses a determination of any extended portion 86a of miniature secondary endoscope 86. Specifically, sensor console 82 operates the sensors of the secondary endoscope tracker as previously taught herein to thereby determine extended portion 86a.
A stage S93 of flowchart 90 encompasses a reconstruction of a shape of the extended portion 86a of miniature secondary endoscope 86. Specifically, optical interrogation console 81 operates optical fiber 85 to thereby facilitate a reconstruction of extended endoscope portion 86a by telescopic endoscope tracker 80 as sensed by sensor console 82.
A stage S94 of flowchart 90 encompasses a determination of a position of extended portion 86a within optical coordinate system 100 relative to the distal end of primary endoscope 84 by telescopic endoscope tracker 80.
Stages S91-S94 are repeated as many as necessary until the tracking of endoscopes 84 and 86 is terminated.
Referring to
Reference tracker 87 is broadly defined herein as any type of device or system for tracking endoscope or the like within a reference coordinate system. Examples of reference tracker 87 include, but are not limited to, an electromagnetic tracking system, an optical tracking system and an imaging tracking system. With this embodiment, the determination of a position of endoscope 84 within a reference coordinate system during stage S91 (
Motor(s) 88 may be operated to advance/rotate miniature secondary endoscope 86 beyond/within primary endoscope 84 via mechanical actuation. Preferably, motor(s) 88 operate in accordance with a closed-loop control with feedback from the sensors of the endoscope tracker. Feedback to motor(s) 88 may also be provided from the output of the shape determination algorithm via telescopic endoscope tracker 80. In this way, mechanical control of miniature secondary endoscope 84 may be performed in a semi-automated or fully-automated manner by taking into account structural features identified with pre-procedural or intra-procedural images.
Referring to
Still referring to
From the description of
While various exemplary embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that the exemplary embodiments of the present invention as described herein are illustrative, and various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the present invention. For example, although the invention is discussed herein with regard to FBGs, it is understood to include fiber optics for shape sensing or localization generally, including, for example, with or without the presence of FBGs or other optics, sensing or localization from detection of variation in one or more sections in a fiber using back scattering, optical fiber force sensing, fiber location sensors or Rayleigh scattering. In addition, many modifications may be made to adapt the teachings of the present invention without departing from its central scope. Therefore, it is intended that the present invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out the present invention, but that the present invention includes all embodiments falling within the scope of the appended claims.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IB2012/050112 | 1/10/2012 | WO | 00 | 7/29/2013 |
Number | Date | Country | |
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61437387 | Jan 2011 | US |