DE102014210056A1 - Method for controlling a surgical device and surgical device - Google Patents

Abstract

A method of driving a surgical device comprises: - marking a first position of the surgical device; Moving the surgical device to a second position; and - driving a tripod of the surgical device to automatically move the surgical device back to the first position.

Description

background

The invention relates to surgical devices, such as surgical microscopes, with a robotic tripod.

Robotic tripods allow you to automatically move a surgical device to use it, for example. B. to bring in a specific position and orientation.

• • Intraoperative Prozeduren in denen das Gerät im Weg stehen würde.
• • Intraoperative Prozeduren in denen das Gerät nicht gebraucht wird.
• • Rollenwechsel zwischen Chirurg und Assistent.
• • Wiederfinden eines bestimmten Punktes im Situs, z. B. der Ort einer Biopsie
• • Wiederfinden eines Situs aus einer vorhergehenden, navigierten Operation.
• • Wechsel zwischen mehreren Situs während einer Operation.

During surgery, there are various situations in which a surgical device is to be brought back by means of the tripod in a specific position, which it had previously taken, for. B .:

• • Intraoperative procedures in which the device would get in the way.
• • Intraoperative procedures in which the device is not needed.
• • Role change between surgeon and assistant.
• • Retrieval of a specific point in the situs, eg. B. the location of a biopsy
• • Retrieving a situs from a previous, navigated operation.
• • Switching between multiple sites during surgery.

Usually, surgical devices are manually returned to the desired position in these cases. The manual repositioning, however, has several disadvantages: To move the system, the surgeon usually has to use at least one hand and thus interrupt his actual activity. This takes time and interrupts the surgeon in his workflow. In extreme cases, the surgeon even has to get up to reposition the device.

Furthermore, the device must be within the reach of the surgeon and be moved or moved by another person with sterile gloves. This restricts the space in which the system can stand during non-use. An operating microscope as an example of a surgical device can be moved in at least 8 degrees of freedom (3 degrees of freedom for position, 3 degrees of freedom for orientation and the settings of focus & zoom). This is a complex task and requires high motor skills and practice.

In part, the place of interest to which the surgical device is to be brought back can not be found visually without using further optical markers. However, these markers could mechanically slip, smear, get in the way, not have enough distinguishing features to distinguish them from other markers, or there could simply be too many markers in the vicinity of a particular desired location.

Overview of the invention

The present invention has the object to control a surgical device such that the device is automatically returned to a specific position, which it has already taken before.

This object is achieved by the control system according to claim 1, by the position control device according to claim 9 and by the surgical microscope according to claim 10.

In one embodiment, a method of driving a surgical device includes marking a first position of the surgical device. In this case, a first camera image can be recorded in a first position of the surgical device. Preferably, in this case at least one 3-D camera is used, which may be integrated in the surgical device and / or in the stand, or which may be mounted on the surgical device and / or on the stand.

Thereafter, the surgical device is moved to a second position and a tripod of the surgical device is actuated to automatically move the surgical device back to the first position. The return of the surgical device may be triggered by user input, or it may automatically, for example, according to a preset positioning plan for surgery, the surgical device after completion of a measurement or engagement at the second position are moved back to the first position. The tripod can in this case comprise a robotic tripod system, which is movable by electrically actuatable actuators. This allows a once-marked position of the surgical device to be restored.

After the surgical device has been moved to the first position, a second camera image can be taken and the first and second camera images can be analyzed. Finally, the position of the surgical device can be adjusted according to the results of the analysis. As a result, additional errors can be compensated in the restoration of the first position of the surgical device, which could not even be detected by a possibly existing sensors of the tripod, z. B. Errors due to brain shift or patient movement.

The inventive method thus allows the surgical device once In the meantime, even if the patient has moved slightly in the meantime, or if tissue structures of the patient have deformed in the meantime, he can reliably restore his position relative to a situs.

According to an embodiment, it may be provided that the marking of the first position of the surgical device is triggered by a user input by means of an operating element of the surgical device. Thus, a surgeon can mark certain points during surgery that are of particular interest to him.

According to a further embodiment it can be provided that the marking of the first position of the surgical device is carried out automatically, wherein the automatic marking can take place at positions at which the surgical device or an external device performs interventions or measurements on which virtual surgery was performed prior to the operation or real markers that were deemed important by an automatic context analysis and / or at which a given mode of the surgical device has been activated. Thus, during surgery, the surgical device automatically marks points in the site that may be of interest to the surgeon. The surgeon can then choose which of these automatically marked points should be approached later.

According to a further embodiment it can be provided that the marking of the first position of the surgical device is carried out automatically before any change in position of the surgical device. Thus, each once set position of the surgical device can be restored.

Furthermore, it can be provided that the analysis of the first and the second camera image comprises the generation of a respective mask from the first and the second camera image and the matching of the two masks. For example, a mask may comprise a pixel matrix, with a matrix element set to "1" if a predetermined structure, such as a blood vessel, exists in the corresponding image area and set to "0" if the structure in the corresponding one Image area is not available. From the comparison of the two masks, a coordinate transformation can be determined, which can be used to further adjust the position of the surgical device.

It can be provided that the analysis of the first and the second camera image comprises the extraction of pixels with a predetermined characteristic and the matching of the respective extracted pixels of the first and the second camera image. In this case, methods from the computer vision can be used (pattern recognition, edge detection, ...) to extract the pixels and align them with each other.

Furthermore, it may be provided that the surgical device comprises a navigation device which generates position data of the surgical device which are detected in the first position of the surgical device, and wherein the detected position data of the navigation device in the step of driving the tripod of the surgical device to the Surgical device automatically move back to the first position to be used. This can further minimize inaccuracies in the positioning of the surgical device.

According to one embodiment, the surgical device may comprise a surgical microscope, wherein the first position of the surgical microscope comprises the position of the surgical microscope in space, and / or a zoom setting and / or a focus setting of the surgical microscope. Thus, not only the position is restored, but also the essential imaging settings of the surgical microscope can be restored, so that the surgical microscope after moving to the marked, first position there can be used immediately with the previously used settings.

In accordance with another aspect of the present invention, there is provided a surgical device position control device having a processor configured to perform the method described above.

According to another aspect of the present invention, there is provided a surgical microscope comprising a microscopy optics, a camera for taking a camera image in a position of the surgical microscope, a tripod system which is controllable by means of actuators to position the surgical microscope in space; and a position control device as mentioned above.

Detailed description of the invention

In the following some embodiments of the invention will be explained with reference to the accompanying figure. It shows:

1 a schematic representation of a surgical microscope as an example of a surgical device according to the invention.

1 shows a surgical system 10 comprising a surgical microscope 12 which is attached to a tripod 14 is movably suspended. The tripod 14 includes several arms, which move through axes of movement 16 connected to each other. The tripod 14 is designed as a robotic tripod, wherein the axes of movement are each controlled by actuators and wherein sensors are provided which a position of the tripod 14 can capture. In the schematic representation in 1 are only two axes of movement 16 schematically illustrated, but usually a tripod will include at least six axes of motion to a positioning of the surgical microscope 12 in three spatial directions and with three degrees of freedom to allow the rotational movement.

At the surgical microscope 12 is a camera in the example shown 18 attached, which by the (not shown) microscopy optics of the surgical microscope 12 captured image and an external position control device 20 can provide. According to some embodiments, at the surgical microscope 12 and / or tripod 14 several cameras 18 be provided. The position control device 20 can be provided as an external device, as in 1 shown, or may be in the surgical microscope 12 or in the tripod 14 be integrated.

Furthermore, in the in 1 example shown a navigation device 22 provided, which is the position of the surgical microscope 12 in the room for example by means of the surgical microscope 12 attached antennas or markers 24 detected, and which the detected position data de operating microscope 12 to the position control device 20 transmitted.

The operation of the in 1 shown exemplary surgical system 10 shown.

The surgical system 10 can be used to select user-marked surgical microscope positions 12 to drive again. During the operation, the surgeon marks certain positions of the surgical microscope 12 who are of particular interest to him. This can z. B. temporarily set sutures, vascular staples or places where a tissue sample (biopsy) was taken. In the simplest case, he would like to temporarily work without a device. Then he takes the work with the surgical microscope 12 again, this should take exactly the last position again.

The method of how the user manually set a marker is open. This can be z. B. done by means of a haptic control, z. B. a button on the surgical microscope 12 or at a further control element, such as a foot switch, by means of a predetermined gesture, which can be detected optically or for example by means of a touch screen input element, or by means of a voice command, which can be detected by an acoustic input element.

Alternatively or additionally, it may be provided that in the surgical system 10 be automatically marked during the surgery positions in the situs. These positions may be, for example, locations where scans were taken with an endoscope, locations where tissue samples were taken with a biopsy forceps, and / or locations where measurements with a specific result were made with an electrophysiology unit , Furthermore, a position marker can automatically be set at locations at which the user has set virtual markers during preoperative planning prior to the operation.

Furthermore, marked positions may be predetermined by certain other surgical instruments, such. B. by a trocar, the surgical microscope 12 is aligned so that the optical axis of the microscopy optics is directed vertically into the trocar.

An automatic marking of positions can be carried out at all position changes, so that each once set position is marked and can be restored later. By means of the position control device 20 or by means of a further control unit, an automatic context analysis can be carried out, with the positions being marked as important on the basis of the results of the context analysis. Furthermore, position markers may be set at locations where applications running on the device have been started, such as the position of the surgical microscope 12 , where the start of an IR800 / FLOW800 recording has been detected, and position markers can be set in locations where a particular mode has been activated on the device, such as a fluorescence mode of the surgical microscope 12 ,

As soon as at least one position has been marked, the user can select any marked position via a user interface. Subsequently, the position control device controls 20 the tripod 14 of the surgical microscope 12 such that the selected position is adjusted with the correct orientation. In addition, other degrees of freedom can also be adjusted be such. B. the zoom and focus adjustment of the surgical microscope 12 ,

A robotic tripod, like the one in 1 schematically illustrated tripod 14 , has motors and angle and possibly displacement sensors in all degrees of freedom. The tripod has at least 6 degrees of freedom in order to be able to position the device without any restrictions in the room.

The user can store the position (position of the device), the orientation (direction in which the device is aimed) via an operating interface and, if necessary, other degrees of freedom that can be set automatically.

Following a command from the user, this setting of the tripod is restored in which the individual actuated degrees of freedom return to their original position.

According to some embodiments, the marked position, ie, the target position, is in restoring an already occupied position of the surgical microscope 12 , not specified by the user during the operation, but determined by automatic device functions. For this purpose, a signal from an external tool such. B. a correspondingly equipped biopsy forceps (detachment of a tissue sample) or an imaging device (confocal endomicroscope, simple endoscope) when recording an image create a marker. This marked position is either immediately or, for example, only after analysis z. B. the tissue sample or after completion of the recording of the imaging device as a target position available.

During the operation planning, based on the collected data from z. B. MRT or CT a specific position can be marked. It can be determined, for example, that a view along a sulcus on a lesion is an advantageous position for the surgical microscope 12 and this position may then be determined from the acquired MRI or CT data and in the position control device 20 be deposited as a marked position.

Furthermore, during the operation itself can be seen from the pictures of the camera 18 of the surgical microscope 12 for certain purposes optimal positions are determined, for example, for a view vertically into a trocar.

For more accurate positioning when restoring a marked position, next to the position indicators of the tripod 14 also information from (preferably 3-D) camera 18 used, with several cameras 18 can be provided. The cameras 18 can in the surgical microscope 12 self-integrated, on the tripod 14 and / or be mounted externally. This could be the ever-existing tolerances of the mechanics and sensors of the tripod 14 be compensated.

In addition, by the camera 18 The information obtained compensates for additional errors arising solely from the sensors of the tripod 14 could not capture and thus offset, for. B. brain shift or patient movements.

The image data could also be used to determine the extent to which the stored point is actually valid: when marking a position, a camera image is taken. After resuming a stored position, this camera image can be used in several ways to validate the plausibility of the position.

According to one embodiment, a camera image is captured again after the original position is resumed. This is compared by an algorithm (eg correlation) for similarity to the original camera image. A score calculated by this algorithm decides the action then taken, e.g. As a warning to the user falls below a certain limit.

According to another embodiment, an image processing algorithm calculates the deviation from the original camera image, without the position of the surgical microscope 12 by the system virtually shifting and distorting the camera image. If the detection of the deviation succeeds, it can alert the user to this deviation and offer him to automatically compensate for this by automatically realigning himself.

According to a further embodiment, a camera image is acquired again after the original position has been resumed. Both in the original camera image and in the new camera image, characteristic anatomies (eg vessels, sulki, etc.) are segmented, ie a mask is created which is "1" if the anatomy is present at the corresponding pixel and " 0 "if the anatomy is not present at the corresponding pixel. Subsequently, both segmentation results are registered to each other (non-elastic or elastic) to obtain a coordinate transformation rule between both camera images, which can finally be used to transform the original point in the site into the new image. Thus, the position of the surgical microscope 12 if necessary readjusted and thus the accuracy can be increased. Of course Both camera images can be registered to each other without segmentation.

According to a further embodiment, a camera image is acquired again after the original position has been resumed. Both in the original camera image and in the new camera image, pixels, so-called keypoints, are automatically extracted, which have a significant characteristic (eg corners) and thus can be found with high probability in the other image as well. In addition, so-called keypoint detectors from Computer Vision are used. Each keypoint is then described by a feature vector in which its local neighborhood is analyzed. Feature descriptors from Computer Vision are used for this. After the keypoints have been detected and described for both images, correspondences between similar keypoints are now created in both images, by taking for example those points for which the Euclidean distance - or another distance measure - between the feature descriptors is minimal. Alternatively, hashing techniques can be used to create correspondence. Correspondence creation can be done in a multi-step process to minimize outliers. With the found correspondences a coordinate transformation (linear, affine, quadratic, ...) can now be estimated. This coordinate transformation is now used to move to the original point in the situs. If the keypoints and correspondences are sufficiently dense, local tissue deformations can also be compensated by using only a subset of the keypoints that are local to the desired site in the original image to calculate the transformation.

According to a further embodiment, the user is offered the camera image recorded at the time the marker was set for comparison with the current camera image. The user decides on the basis of the recorded camera image, the comparison with the current Situs and his experience knowledge, whether the current position can still agree with the original position and to what extent deviations have occurred.

According to some embodiments, navigation data can be used to increase the speed. In many operations, navigation devices are used, such as the in 1 schematically shown navigation device 22 , If the navigation device 22 In addition to the position of the patient, the position of the surgical microscope 12 recorded (position and orientation), this navigation data can be used to the surgical microscope 12 to position more accurately or to recognize and compensate for operating errors during positioning.

• • Patientenbewegungen
• • Bewegungen des OP-Tisches
• • Bewegungen von navigierten Instrumenten
• • Änderungen des Aufstellortes des Stativs

Navigation devices usually detect the position of the different devices absolutely in the room. The tripod 14 itself is only able to grasp its own position and that only relatively by axis 16 to axis 16 , All movements by means of navigation data of the navigation device 22 can be detected using the tripod system 14 even not detected, could also be compensated with such an arrangement. This could be z. For example:

• • Patient movements
• • Movements of the operating table
• • Movements of navigated instruments
• • Changes to the location of the tripod

This measure increases the reliability and usability of the function for restoring a marked position, as well as the safety of use by preventing handling errors due to unintentional misuse.

When restoring marked positions, preoperatively obtained data may be used, according to some embodiments. In many operations, preoperative data are obtained about the position of certain organs or parts of organs. If this data includes the body size and the relative position of the device to the body is known, the device can use this data as additional safety information and z. B. the movement of the tripod 14 stop below a minimum distance to the patient.

The body extent can be obtained from the volume data of an MRI or CT. The body should be at least that of the head, ideally the upper body or whole body. The body extent can be obtained for this purpose from the volume model of the skeleton, in particular the skull bone. The body extent can be obtained from a navigation system from the preoperative data or a surgical microscope with access to this data. In addition, heuristic knowledge could be used to at least roughly determine this data: for example, that the body continues below the head.

The relative position of the surgical microscope 12 to the body can be determined by a navigation system. She can go through the in the surgical microscope 12 built-in camera / s 18 due to image data of anatomical features or due to special markings.

According to another embodiment, the in or on the surgical microscope 12 attached camera / s 18 For example, the direction in which the end effector is moved could automatically inspect for obstruction and, in the event of an impending collision with the operator or patient, stop or at least slow it down.

This can be done with the help of the actuators in the tripod 14 at least one of the cameras 18 be automatically aligned so that they follow the trajectory of the surgical microscope 12 moves, record and monitor for collisions. Only at the destination could then the appropriate camera 18 aligned to the marked position to the above-described plausibility check and fine adjustment of the position of the surgical microscope 12 to enable.

The method described above makes it possible to restore a once-occupied position of a surgical device such as a surgical microscope with high accuracy. As an exemplary embodiment of such a surgical device was a surgical microscope 12 However, it is conceivable to use the method according to the invention in any surgical device that can be positioned in space with the help of a robotic tripod.

Claims (11)

A method of driving a surgical device comprising: - marking a first position of the surgical device; Moving the surgical device to a second position; and - Driving a tripod of the surgical device to automatically move the surgical device back to the first position. A method according to claim 1, characterized in that the marking of the first position of the surgical device is triggered by a user input by means of a control element of the surgical device. A method according to claim 1, characterized in that the marking of the first position of the surgical device is carried out automatically, wherein the automatic marking can take place at positions at which the surgical device or an external device performs interventions or measurements on which prior to the operation virtual or real markers that were deemed important by an automatic context analysis and / or at which a given mode of the surgical device has been activated. A method according to claim 1, characterized in that the marking of the first position of the surgical device is performed automatically before any change in position of the surgical device. Method according to one of claims 1 to 4, characterized in that the method further comprises: - recording a first camera image in the first position of the surgical device; - taking a second camera image after the surgical device has been moved to the first position; - Analysis of the first and second camera image; and - adjusting the position of the surgical device as a function of the results of the analysis. A method according to claim 5, characterized in that the analysis of the first and the second camera image comprises generating in each case a mask from the first and the second camera image and the matching of the two masks. Method according to claim 5 or 6, characterized in that the analysis of the first and the second camera image comprises the extraction of pixels with a predetermined characteristic and the matching of the respective extracted pixels of the first and the second camera image. Method according to one of claims 1 to 7, characterized in that the surgical device comprises a navigation device which generates position data of the surgical device, which are detected in the first position of the surgical device, and wherein the detected position data of the navigation device in the step of driving the Tripods of the surgical device to automatically move the surgical device back to the first position can be used. Method according to one of claims 1 to 8, characterized in that the surgical device comprises a surgical microscope, wherein the first position of the surgical microscope comprises the position of the surgical microscope in space, and a zoom setting and / or a focus adjustment of the surgical microscope. A position control device for a surgical device, characterized in that the control device comprises a processor, which is designed to perform the method according to one of claims 1 to 9. A surgical microscope, comprising: - a microscopy optic; A camera for taking a camera image in a position of the operation microscope; - A tripod system, which is controlled by actuators to position the surgical microscope in the room; and a position control device according to claim 10.

Images