CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the priority of German patent application No. 102017110103.9, filed May 10, 2017, the entirety of which is hereby incorporated by reference herein, including the English translation thereof.

TECHNICAL FIELD

The present invention relates to a visualization system for visualizing a three-dimensional target area of an object and can for example be formed as a stereo surgical microscope.

BACKGROUND

Surgical operating microscopes are used for example in eye surgery for interventions on the anterior and/or posterior chamber of the eye. By means of the stereo surgical microscope, during a surgery the user or surgeon receives a stereoscopic top view of the target area in which the surgery is to be carried out, such that the surgeon can orientate himself well. In the case of such a surgery it is desirable for the surgeon to have a good visual grasp of the distance of the surgical instrument, which he is using, to a predetermined structure in the target area.

The object of the invention is therefore to provide a visualization system for visualizing a three-dimensional target area of an object, with which a good visualization of a distance of a surgical instrument in the target area to a predetermined structure in the target area can be realized.

SUMMARY

The visualization system according to the invention for visualizing a three-dimensional target area of an object can comprise a measuring device which determines a distance of a surgical instrument in the target area to a predetermined structure in the target area, and which generates a first view of the target area as well as a second view with the surgical instrument and the predetermined structure, wherein the second view runs transverse to the first view or wherein the second view does not lie parallel to the first view. Furthermore, the visualization system can comprise a display unit for representing the views and a control unit, wherein the control unit controls the display unit such that it is in a first display mode when the determined distance is greater than a predetermined first limit value, and such that it switches from the first display mode into a second display mode when the determined distance changes from being greater than a predetermined second limit value, which is smaller than or equal to the predetermined first limit value, to being smaller than the predetermined second limit value. In the first display mode of the views, at least the first view is represented and in the second display mode, when the second view is not represented in the first display mode, the second view is represented in the second display mode, or, when the second view is represented in the first display mode, the second view is represented optically highlighted in comparison with the first display mode.

With the visualization system according to the invention, an automatic switching from the first display mode into the second display mode thus takes place when the value falls below the predetermined second limit value. Thus, the first view, which is for example a top view of the target area, can be represented in the first display mode and the second view can then be represented in the second display mode, such that the user or surgeon can visually perceive the distance between his surgical instrument and the predetermined structure well. The second view can be a side view or a sectional view. With the visualization system according to the invention, the surgeon can thus be provided with a good overview of the target area based on the first view in the first display mode, such that the surgeon can orientate himself well. As soon as the surgeon with his surgical instrument is close to the predetermined structure, the system is switched into the second display mode, in which the distance between the surgical instrument and the predetermined structure is visually represented to the surgeon. The first view can of course still additionally be represented in the second display mode. However, it is also possible that the first view is not represented in the second display mode.

By the optically highlighted representation of the second view in the second display mode is meant in particular that the second view is represented larger and/or brighter than in the first display mode and/or at a different position (e.g. more central) on the display unit than in the first display mode. Furthermore, the colour can additionally or alternatively be changed during the representation.

The display unit can represent the first view stereoscopically. Furthermore, the display unit can represent the second view stereoscopically. The first view can in particular be a top view onto the target area. The second view can be a side view or sectional view. The first and second views can be representations of the target area which are perpendicular to each other or form an angle which lies in the range of from 45° to 90°.

The control unit can control the display unit such that it switches from the second display mode into the first display mode when the determined distance changes from being smaller than the predetermined first limit value to being greater than the predetermined first limit value. When the predetermined first limit value is greater than the predetermined second limit value, there is thus a hysteresis which prevents a switching back and forth in the case of small changes in the region of the predetermined first limit value or of the predetermined second limit value.

Furthermore, the control unit can control the display unit such that, before another switching from the first display mode into the second display mode, a predetermined period must have elapsed after the switching from the second display mode into the first display mode. A hysteresis is also generated thereby, which prevents a switching back and forth.

The measuring device can comprise a microscope which generates the first view by means of optical imaging. The microscope can be formed as a stereo microscope and/or as a surgical microscope

The measuring device can comprise an optical coherence tomography (OCT) device which generates OCT measurement data covering the entire target area. The OCT measurement data can in particular be used for generating the second view. However, they can also additionally or alternatively be used for generating the first view.

Furthermore, the measuring device can comprise a microscope, the measurement data of which are used for generating the first view and/or the second view. In particular, the measurement data of the microscope and the measurement data of the OCT device can be used together for generating the first view and/or the second view.

Furthermore, the measuring device can comprise a distance measurement unit which (preferably continuously) measures the distance between the surgical instrument and the predetermined structure in the target area.

The display unit can for example be formed as an eyepiece of the microscope. The second view can for example be reflected into the eyepiece. Furthermore, the display unit can be formed as a monitor or screen or as a display device that can be mounted on the head of a user (head-mounted display device=HMD device). The monitor or screen, as well as the HMD device can present the views as two-dimensional views or as three-dimensional views. For example, the first view can be represented three-dimensionally and the second view two- or three-dimensionally.

The OCT device can be based on all known OCT technologies. The OCT device can be a time-domain OCT system, a frequency-domain OCT system, a spectral-domain OCT system and/or a swept-source OCT system.

The OCT device and the microscope can, at least in part, use identical optical elements.

Furthermore, a visualization method for visualizing a three-dimensional target area of an object is provided for a visualization system which comprises a measuring device which determines a distance of a surgical instrument in the target area to a predetermined structure in the target area, and which generates a first view of the target area as well as a second view with the surgical instrument and the predetermined structure, wherein the second view lies transverse to the first view or does not extend parallel to the first view, and a display unit for representing the views. The display unit is controlled such that it is in a first display mode when the determined distance is greater than a predetermined first limit value, and such that it switches from the first display mode into a second display mode when the determined distance changes from being greater than a predetermined second limit value, which is smaller than or equal to the predetermined first limit value, to being smaller than the predetermined second limit value, wherein, in the first display mode of both views, at least the first view is represented and in the second display mode, when the second view is not represented in the first display mode, the second view is represented, or, when the second view is represented in the first display mode, the second view is represented optically highlighted in comparison with the first display mode.

The visualization method according to the invention can comprise the method steps described in connection with the visualization system according to the invention. In the same way, the visualization system according to the invention can comprise elements or components in order to carry out the steps described in connection with the visualization method according to the invention.

Furthermore, a computer program product is provided which comprises software code in order to carry out the steps of the visualization method according to the invention when the product is executed (in particular on a control device or a control unit of a visualization system with the measuring device and the display unit).

It is understood that the features named above and those yet to be explained below can be used not only in the combinations indicated but also in other combinations or alone, without departing from the scope of the present invention.

The above summary is not intended to describe each illustrated embodiment or every implementation of the subject matter hereof. The figures and the detailed description that follow more particularly exemplify various embodiments.

