Described below is an endoscope, particularly for minimally invasive surgery.
In comparison with frequently conventional open surgery, numerous methodological-technical restrictions apply to minimally invasive or laparoscopic and in particular scarless surgery. The restrictions relate primarily to visualization, spatial orientation, assessment of the tissue constitution and the spatial confinement of the work area with greatly reduced degrees of freedom. For this reason, complex interventions, in particular, have hitherto not yet been able to be carried out minimally invasively, even though this would be inherently very desirable.
Therefore, intensive research and development efforts are being made globally in order to extend the applicability of minimally invasive surgery.
One major disadvantage of conventional minimally invasive surgery is missing or inaccurate information about the third dimension, since only the organ surfaces are viewed and, for example, the sense of touch cannot be used to localize a tumor internally in an organ. The depth information could be conveyed, in principle, by the projection of volume data sets obtained preoperatively, but this form of augmented or enhanced reality conventionally fails for lack of reliable referencing. In comparison with preoperative diagnostics, intraoperatively a more or less pronounced position and shape change, for example of an intra-abdominal anatomy, can always occur, to which a preoperative data set has to be adapted in each case. Such an adaptation would be possible in terms of software if, in comparison with the related art, more exact information were available about a current surface of an organ for example in an abdominal space. In addition, conventionally a field of view is greatly restricted.
Numerous approaches propose a precise, continuous depth measurement in real time. Conventionally, it is not possible to determine accurate distances between a respective anatomy and the measurement objects used at every point in time of an intervention. The absence of this information is a cause of a large number of problems that currently still exist.
For the further development of medical operations via natural orifices of the body, a precise 3D metrology is the key technology. Without a successful implementation, NOTES (Natural Orifice Transluminal Endoscopic Surgery), or the minimally invasive surgery without scars, which involves operating by access through natural orifices of the body, will not be able to be introduced into clinical care. The use of mechatronic auxiliary systems is essential for NOTES. The systems in turn necessarily require a reliably functioning depth or 3D metrology for collision avoidance, for the compensation of breathing- or respiration-dictated organ deflections and a large number of further functions.
Various solution approaches used hitherto in other technical fields can be used to provide 3D information and corresponding 3D metrology.
Stereoscopic triangulation is a known principle of distance measurement. In this case, an object is imaged from two observation directions by cameras. If a distinctive point is recognized in both recordings, then given a known distance between the cameras, the so-called base, a triangle is spanned which is uniquely determined with the base value and two angles and enables the distance of the point to be calculated. What is usually disadvantageous here, however, is the fact that there are too few distinctive points in the object and too few corresponding points are thus found in the cameras. Such a problem is referred to as the correspondence problem.
In order to avoid such a correspondence problem, so-called active triangulation has been used, which projects from one direction known patterns or, as in the case of phase triangulation, a sequence of sinusoidal patterns onto an object. As a result of the imaging of the object from another direction, the pattern appears distorted depending on the shape of the pattern surface, wherein the three-dimensional surface can in turn be calculated from this distortion, which is likewise referred to as a phase shift. This procedure enables even totally contrastless and markerless surfaces to be measured. What is disadvantageous about this type of 3D measurement in the field of minimally invasive surgery is an only minimal space for accommodating a camera and a projector—fitted at an angle—for projecting pattern sequences. A further disadvantage is that the position with respect to the object must not be altered during a projection sequence, since otherwise the 3D coordinate calculation is greatly beset by errors.
Time of flight
The disadvantage of the 3D coordinate calculation beset by errors on account of an object movement likewise occurs in the so-called time of flight (TOF) methods. Here, likewise, from a location of the object surface, at least four intensity values are measured for different times of flight of an intensity-modulated transmission signal. A computation of these intensity values produces a respective distance value. A further challenge however is in particular the measurement of the time-of-flight differences caused by distance differences in the millimeters range given the very high speed of light in the region of 300 000 km per second. Known systems can measure the distance of a single object point at a resolution of one millimeter by using highly developed detectors and electronics. Only inadequate values for surgery in the centimeters range are achieved for planar TOF distance sensors.
Structure from Motion
This method is based on the fact that, in principle, by the motion of a camera in front of an object, many images are recorded from different directions and triangulation is made possible again, in principle, in this way. However, the so-called correspondence problem arises again in this case, that is to say that a distinctive point has to be recognized in the respective sequential images. Furthermore, it is not possible to calculate absolute, but rather only relative values, since the triangulation base, the distance and the orientation between the temporal recordings are not known or would additionally have to be measured by tracking systems.
The problem addressed is that of providing an endoscope such that a visualization, a spatial orientation and/or an assessment of an object, in particular of tissue, in particular in the case of a spatial confinement of a work volume with reduced degrees of freedom, are/is improved and simplified in comparison with conventional systems. In particular, an applicability to minimally invasive surgery is intended to be extended. Complex minimally invasive interventions are likewise intended to be implementable. A precise, continuous depth measurement in real time is intended to be made possible and accurate distances between endoscope and object are intended to be determinable at every point in time of an intervention. An endoscopic apparatus is intended to be provided such that 3D measurement data of surfaces, in particular in the field of minimally invasive surgery, are generated with a higher data quality in comparison with the related art.
For the integration of optical systems particularly in the field of minimally invasive surgery (MIC), it is important that the optical systems are sufficiently miniaturizable and nevertheless do not lose their performance in the sense of imaging or measurement accuracy. It is necessary to overcome the disadvantage that a reduction of dimensions in an optical system generally likewise means a loss of information transmission capacity, be it that the size of a field of view is reduced or that the resolution capability is reduced. This concerns 3D metrology, in particular since the latter has to likewise transmit the third dimension.
In accordance with one aspect, an endoscope for three-dimensionally detecting a region of an internal space is proposed, wherein the endoscope extends along an original elongate endoscope extent as a longitudinal body having a distal end region which can be angled by up to 180°, in particular up to 110° or 90°, with respect to the original elongate endoscope extent, wherein an apparatus for three-dimensionally detecting the region by active triangulation is formed at least partly in the distal end region.
The three-dimensionally measuring optical system proposed makes it possible to produce measurements of distance to individual points of a surface of an internal space and more exact information about an internal space of a body. An endoscopic apparatus is proposed which, particularly for minimally invasive surgery, provides three-dimensional measurement data of surfaces with higher data quality in comparison with the related art. So-called active triangulation is particularly advantageously used, which projects from one direction known patterns or, as in the case of phase triangulation, a sequence of sinusoidal patterns onto an object. Configurations such as are known from DE 10 232 690 A1 are particularly advantageous.
In accordance with one advantageous configuration, the apparatus for three-dimensionally detecting the region can have a projection device for projecting an, in particular redundantly coded, color pattern onto the region and a detection device for detecting an image of the color pattern projected onto the region.
In accordance with a further advantageous configuration, a transmission device can be designed for transmitting the image generated by the detection device to an evaluation device for processing the image to form three-dimensional object coordinates which can be represented as a 3D image for an operator by a display device.
In accordance with a further advantageous configuration, the projection device and/or the detection device can be formed at least partly in the distal end region.
In accordance with a further advantageous configuration, the projection device and the detection device can be formed completely or one of the two can be formed completely and the other is formed partly in the distal end region in such a way that both have in each case a viewing direction substantially perpendicular to the elongate extent of the angled distal end region.
In accordance with a further advantageous configuration, the two viewing directions can be rotatable about a rotation axis running along the elongate extent of the distal end region, in particular an axis of symmetry of the distal end region. A restricted field of view can be extended in this way since, by a depth map, a large number of individual images of the internal space can be joined together to form a virtual panorama, which can likewise be referred to as “mosaicing” or “stitching”. Such an extension of the field of view can considerably facilitate performance of an operation, for example, and effectively improve a safety level.
In accordance with a further advantageous configuration, either the projection device or the detection device can be formed completely and the other is not formed in the distal end region and both can have substantially parallel viewing directions in an angled state.
In accordance with a further advantageous configuration, the two viewing directions substantially can run along the original elongate endoscope extent.
In accordance with a further advantageous configuration, it is possible that the endoscope can be angled by approximately 90° with respect to the regional elongate endoscope extent.
In accordance with a further advantageous configuration, a portion of the projection device and of the detection device which is not formed in the distal end region can be formed in the longitudinal body adjoining the distal end region.
In accordance with a further advantageous configuration, a portion of the projection device and of the detection device which is not formed in the distal end region can be formed outside the longitudinal body at a side of a proximal end region of the longitudinal body.
In accordance with a further advantageous configuration, the detection device or the projection device can be formed outside the longitudinal body and the other is formed in the distal end region.
In accordance with a further advantageous configuration, proceeding from the detection device or projection device formed outside the longitudinal body, an image guide device can be formed into the longitudinal body to an objective adjoining the distal end region in the distal end region.
In accordance with a further advantageous configuration, if the projection device is formed in the distal end region, a light guide device to the projection device can be formed from a light source outside the longitudinal body into the longitudinal body.
In accordance with a further advantageous configuration, it is possible that the endoscope can be rigid and the distal end region can be angled by a joint.
In accordance with a further advantageous configuration, it is possible that the endoscope can be flexible and the distal end region can be angled by a flexible material or a joint.
In accordance with a further advantageous configuration, the endoscope has a mechanical mechanism or electromechanical mechanism by which the distal end region can be angled.
In accordance with a further advantageous configuration, the transmission device can transmit the image by at least one transmission medium from the detection device to the evaluation device.
In accordance with a further advantageous configuration, optical or electrical image data can be detectable by mirrors, electrical lines, light guides or transparent or electrically conductive layers as transmission media.
In accordance with a further advantageous configuration, a position determining device can be formed, by which a position of the projection device and of the detection device can be determinable.
In accordance with a further advantageous configuration, the projection device can project white light onto the region of the internal space alternately to the color pattern, and the detection device can detect color images of the region alternately to 3D images which are calibratable by the white light.
In accordance with a further advantageous configuration, the display device can provide the 3D images and the color images of the region in real time for an operator.
In accordance with a further advantageous configuration, the detection data rate of the 3D images and of the color images can be in each case between 20 and 40 Hz, in particular 25 Hz.
In accordance with a further advantageous configuration, the evaluation device can fuse three-dimensional object coordinate data of the region with point cloud data of the region obtained by at least one further measuring device, in particular a magnetic resonance imaging device or a computed tomography device.
These and other aspects and advantages will become more apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings of which:
Reference will now be made in detail to the preferred embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
The projection device 1 here is positioned completely in the distal end region. Further component parts of a projection device 1 can be a light source, for example at least one light emitting diode LED, drive electronics and further known projector elements. A detection device 3, for example a camera, for detecting an image of the color pattern projected onto the object is arranged outside the distal end region in the longitudinal body adjoining the distal end region. In accordance with the exemplary embodiment in accordance with
In accordance with
Using a light guide, an image of an object can thus be detected by the detection device 3 by the objective 15. In accordance with
The endoscope E enables an enlargement of a triangulation base and measurements of surfaces and the 3D extents thereof in real time. Thus, it is now possible to enlarge a usable cross-sectional area for the optical components of the endoscope E. The Lagrange invariant can be increased, this being a measure of the optical information transmission performance in optics. In this way, an effectively higher lateral resolution and a depth resolution are brought about particularly in the 3D area in the endoscope. Equally, in comparison with the related art in accordance with
b shows the second point in time, at which the operator, specifically here a surgeon, uses point cloud data of the region W obtained by at least one further measuring device, in particular a magnetic resonance imaging device or a computed tomography device, in addition to images and 3D images. In this case, the evaluation device 7 can fuse three-dimensional object coordinate data of the region W or a 3D image with a point cloud data of the region that are obtained by at least one further measuring device, in particular a magnetic resonance imaging device or a computed tomography device. Using this additional information, the region to be treated, for example a liver L, can be detected by the detection device 3 in such a way that defective locations or diseased tissue, for example a tumor T, can be localized and removed. When a 3D endoscope is used as measuring means for the three-dimensional measurement of a surface of an organ, the fusion with in particular preoperatively obtained point clouds is additionally performed in accordance with
An endoscope for three-dimensionally detecting an internal space R of a body are disposed, wherein a projection device 1 for projecting a color pattern onto a region W of the internal space R and a detection device 3 for detecting an image of the color pattern projected onto the region W are positioned at least partly in a distal end region of an elongate endoscope extent and the distal end region can be angled by up to 180° with respect to the original elongate endoscope extent. A triangulation base for evaluating images by active triangulation for generating 3D images of the region W can be simply and effectively enlarged in this way. Such endoscopes can particularly advantageously be employed in minimally invasive surgery or in technical endoscopy.
A description has been provided with particular reference to preferred embodiments thereof and examples, but it will be understood that variations and modifications can be effected within the spirit and scope of the claims which may include the phrase “at least one of A, B and C” as an alternative expression that means one or more of A, B and C may be used, contrary to the holding in Superguide v. DIRECTV, 358 F3d 870, 69 USPQ2d 1865 (Fed. Cir. 2004).
Number | Date | Country | Kind |
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102013200898.8 | Jan 2013 | DE | national |
This application is the U.S. national stage of International Application No. PCT/EP2013/075042, filed Nov. 29, 2013 and claims the benefit thereof. The International Application claims the benefit of German Application No. 102013200898.8 filed on Jan. 21, 2013, both applications are incorporated by reference herein in their entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2013/075042 | 11/29/2013 | WO | 00 |