Field of the of the Present Disclosure
The disclosure relates to a miniaturized scanning system to generate 2D movement of a distal part of a medical tool.
Background Art
The Applicant has developed a confocal imaging system based on a fiber bundle probe for in vivo in situ imaging of biological tissues as described for example in US Patent Application 2005/0242298 which is fully incorporated herein by reference. Such a system, also referred as a fibered confocal microscope, is for example represented schematically on
The single images acquired by fibered confocal microscopy typically cover an area of 240×200 μm2. The smallness of the image size is due on the one hand to the necessity of a high level of resolution and, on the other hand, because the optical lenses housed in the optical head and the fiber bundle probe carrying the images are minimized for minimal invasiveness. A single image is not always large enough for a conclusive diagnostics and solutions have been developed to obtain high resolution images with a large field of view based on scanning the tissue area by moving the optical head of the imaging system and merging the collected images. US Patent Application 2009/0041314 in the name of the applicant describes image mosaicing techniques that can be used to provide efficient and complete representation of an enlarged field of view. With a mosaicing algorithm as described in US 2009/0041314, a sample scan of 3 mm2 on tissue typically requires maintaining a distance of 150 μm from a previously traced line with an approximate precision of 25 μm for a continuous duration of approximately one minute. With manual sweeping, it is difficult to obtain this precision for such a long time. Further, manual sweeping may not provide the smoothness of the motion with minimal accelerations and/or changes of directions which are important when the surface to be scanned over is a biological tissue.
Several assisted handheld instruments are presented in the literature (see for example B. C. Becker, R. A. MacLachlan, L. A. J. Lobes, and C. N. Riviere, “Semiautomated intraocular laser surgery using handheld instruments”, Lasers in Surgery and Medicine, vol. 42, pp. 246-273, 2010).
US 2001/0055462 from Siebel et al. describes an endoscopic image acquisition system, in which a unique optical fiber is driven across the field of view using two pairs of piezoelectric actuators, placed along the optical fiber at a distal end of the imaging system and oscillating in quadrature, thereby forcing the fiber to bend with the tip of the fiber describing a spiral. The fiber movement is driven close to the resonance frequency of the piezoelectric actuators so that large bending amplitudes can be reached. However, high resonance frequency is required to image a tissue in real time and this technique can hardly be used with heavy movable element.
The Applicant proposes herein under a miniaturized scanning system that can generate a 2D movement of a distal part of a medical tool, for example a surgical or endoscopic tool, while preserving the scanning accuracy, its reproducibility and the smoothness of the movement, and may be applied to any medical tool in which the distal part comprises a bulky movable element, e.g. a fiber bundle associated with a distal optical head, a catheter, a therapeutic device or the like.
In at least one aspect, embodiments disclosed herein relate to a miniaturized scanning system to generate movement of a flexible device positioned at a distal part of a medical tool. The miniaturized scanning system comprises:
2D motion of the end of the flexible device can thus be obtained, possibly by actuation motors, for example electrical motors, located at a proximal part of the medical tool, i.e. apart from the part intended to intrude in the operation region when applied to a surgical or endoscopic medical tool. Further, the scanning system may be miniaturized while preserving the scanning accuracy, reproducibility and smoothness of motion of the end of the scanned device.
According to an embodiment, the abutment comprises an axially symmetric structure to be mounted around said device.
According to a further embodiment, the pusher mechanism comprises a movable sleeve with said end portion attached thereto, wherein the movable sleeve is mounted around said inner shaft and configured to rotate around said longitudinal axis of the inner shaft, the rotation of the movable sleeve resulting in a change of the contact point between said end potion and said external surface of the abutment.
Addressing the scanned surface is thus performed in a polar coordinates referential.
According to an embodiment, the movable sleeve may be configured to be simultaneously rotated around said longitudinal axis and translated along said axis.
According to an embodiment, the miniaturized scanning system may further comprise an outer shaft to be mounted around said movable sleeve, wherein said movable sleeve is coupled to an inner surface of the outer shaft to perform a helical movement with respect to said inner surface of the outer shaft.
According to an embodiment, said movable sleeve and inner surface of the outer shaft are coupled by a screw system.
According to a further embodiment, said external surface of the abutment has a conical shape calculated such that the simultaneous rotation and translation movement of the movable sleeve results in a spiral motion of an end of the device.
According to an embodiment, the miniaturized scanning system may further comprise a rotary drive mechanism of the movable sleeve around said longitudinal axis of the inner shaft.
According to an embodiment, the rotary drive mechanism comprises a toothed wheel arranged in a hollow portion of the inner shaft and a drive rod.
According to a further embodiment, the pusher mechanism comprises at least two end portions configured to translate independently.
According to an embodiment, the miniaturized scanning system may further comprise at least one driving motor to drive the at least one end portion of the pusher mechanism.
According to a further embodiment, said end portion comprises an edge configured to be tangent to the external surface of the abutment.
In a second aspect, embodiments disclosed herein relate to a robotized device comprising a flexible device to be positioned at a distal part of a medical tool and a miniaturized scanning system according to the first aspect to generate a movement of an end of said device.
According to an embodiment, said flexible device is one of an imaging device, a therapeutic device, a hollow conduit.
In a third aspect, embodiments disclosed herein relate to a medical tool comprising:
According to an embodiment, the miniaturized scanning system comprises at least one driving motor positioned at a proximal part of the medical tool.
In a fourth aspect, embodiments disclosed herein relate to a fiber confocal microscopy system for inspecting a biological tissue comprising:
According to an embodiment, the miniaturized scanning system comprises at least one driving motor positioned at a proximal part of the microscope.
In a fifth aspect, embodiments disclosed herein relate to a method for high resolution high field of view in vivo imaging of a biological using a confocal microscope with a distal part to be in contact with said biological tissue, wherein said distal part comprises an optical head connected to an optical fiber bundle, the method comprising:
According to an embodiment, the motion of the optical head is a spiral motion.
Other aspects and advantages of the disclosure will be apparent from the following description and the appended claims.
Specific embodiments of the present disclosure will now be described in detail with reference to the accompanying Figures. Like elements in the various Figures may be denoted by like numerals. Embodiments of the present disclosure relate to a miniaturized scanning system to generate movement of a flexible device positioned at a distal part of a medical tool and a robotized device comprising said miniaturized scanning system.
The optical probe 1 as shown in
In
The inner shaft 4 is configured to guide the optical probe. As shown in the example of
The pusher mechanism 3 is adapted to engage with the abutment 2. In the embodiment as shown in
In the example as shown in
The external surface 20 of the abutment may be calculated to determine the 2D movement of the end of the scanned device when the scanning mechanism is actuated. For example, the 2D movement may be a spiral.
The working principle of the miniaturized scanning system as shown in
In
The tip point P thus follows a trajectory passively constrained by the mechanics of the system. The precision of following the desired trajectory may thus be limited only by the precision of the mechanical construction of the pieces. In the embodiment as described in
The present disclosure may be implemented for in-vivo imaging by integration to a fibered confocal microscope, for example the Cellvizio® imager from the Mauna Kea Technologies® (Paris, France). This system may perform confocal fluorescence imaging, records images of size 240×200 μm2 with 1.2 μm lateral and 3 μm axial resolutions at a rate 12 frames/sec, and may use the mosaicing algorithm presented in US Patent Application 2009/0041314. The confocal probe may consist of a flexible bundle of optical fibers and an optic-head hosting the micro lenses, located at the tip. The outer diameter of the flexible bundle is 1.4 mm. The optic-head is for example a 12 mm long cylinder with an outer diameter of for example 2.6 mm.
The outer shaft is for example around 3.5 cm long with an inner diameter of 5 mm. In order to take images the surgeon manually brings the tip of the outer shaft to the locus of interest and slightly presses on the tissue. The outer edge of the outer shaft stabilizes the region to be scanned. The tissue covered by the edges of the outer shaft slightly bends and touches the tip of the optic-head inside. The surgeon presses a button to energize the motor that drives the movable sleeve. With the rotation of the movable sleeve the optic-head automatically scans the tissue following a spiral path. When the scan is completed, in approximately one minute, the driving motor stops and the surgeon is noticed with the turn-on of a led. At this point the scan is over and the images for mosaicing are collected. The surgeon releases the tube from the tissue and presses another button to initialize the system for another scan. This button activates the driving motor in the reverse direction to rewind to its initial position in about 5-10 seconds.
It is therefore possible with the miniaturized scanning mechanism of the present disclosure to scan an area of 3 mm2 on the tissue. This corresponds to a circular region of approximately 2 mm in diameter. One minute duration is targeted for a full spiral scan. It corresponds to a linear speed of approximately 0.38 mm/sec on a spiral with 0.15 mm distance in between its sequential curves. The distance between the two successive scan-lines is restricted by the image size and should be less than 0.2 mm (200 μm).
As mentioned above, during scanning the outer shaft is pressed on the tissue. The outer shaft and the optic-head get into contact inside the tube. This contact may be maintained when the mechanism is moved inside the tube throughout the scan. With the conical structure 2 as described in
While the previous embodiment was described to generate movement of an optical probe, the mechanism of the miniaturized scanning device of the present disclosure is independent from the device characteristics and geometry. In particular, the miniaturized scanning device does not necessitate any special operation on the object to be manipulated and fixing the device at the abutment suffices. Consequently, the same could have been used to generate movement of any flexible device to be positioned at a distal part of a medical tool, or at least any device comprising a flexible portion, for example a hollow conduit (e.g. a catheter), a therapeutic device (e.g. a plasma jet, an electrode, surgical tools), an imaging device (e.g. optical probe for an endoscope, an endomicroscope).
While the disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the disclosure as disclosed herein. Accordingly, the scope of the disclosed invention should be limited only by the attached claims.
Filing Document | Filing Date | Country | Kind |
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PCT/IB2013/001024 | 4/8/2013 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
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WO2013/153448 | 10/17/2013 | WO | A |
Number | Name | Date | Kind |
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20010055462 | Seibel | Dec 2001 | A1 |
20050242298 | Genet et al. | Nov 2005 | A1 |
20080015445 | Saadat et al. | Jan 2008 | A1 |
20090041314 | Vercauteren et al. | Feb 2009 | A1 |
20100179386 | Kobayashi | Jul 2010 | A1 |
20110257486 | Chang et al. | Oct 2011 | A1 |
Number | Date | Country |
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1142529 | Oct 2001 | EP |
S63122417 | May 1988 | JP |
2001-174744 | Jun 2001 | JP |
2010-162090 | Jul 2010 | JP |
Entry |
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International Search Report for corresponding International Application No. PCT/IB2013/001024, mailed Oct. 1, 2013 (2 pages). |
Written Opinion for corresponding International Application No. PCT/IB2013/001024, mailed Oct. 1, 2013 (7 pages). |
Brain C. Becker et al.; “Semiautomated Intraocular Laser Surgery Using Handheld Instruments;” Laser in Surgery and Medicine, 42:264-273; Pittsburgh, Pennsylvania (2010) (10 pages). |
Notification of Reasons for Refusal issued in corresponding Japanese Patent Application No. 2015-505029, mailed on Nov. 29, 2016 (10 pages). |
Number | Date | Country | |
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20150057499 A1 | Feb 2015 | US |
Number | Date | Country | |
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61623985 | Apr 2012 | US |