ASSEMBLY COMPRISING AN OCT DEVICE FOR ASCERTAINING A 3D RECONSTRUCTION OF AN OBJECT REGION VOLUME, COMPUTER PROGRAM, AND COMPUTER-IMPLEMENTED METHOD FOR SAME

Abstract

The invention relates to an assembly (10) comprising an OCT device (20) for scanning an object region volume (22) arranged in an object region (18) using an OCT scanning beam (21), an object (24) with a section, which can be arranged in the object region (18) and which can be located in the object region volume (22) by means of the OCT device (20), in the object region volume (22), and a calculating unit (60) which is connected to the OCT device (20) and contains a computer program for ascertaining a 3D reconstruction of the object region volume (22) and for ascertaining the position of the section of the object (24) in the object region volume (22) by processing OCT scanning information obtained by scanning the object region volume (22) using the OCT device (20). According to the invention, the computer program has a calculation routine for ascertaining a target area (90) in the 3D reconstruction of the object region volume (22), said calculation routine determining a reference variable for the object (24) relative to the target area (90). The object (24) is designed as a surgical instrument which has a capillary with an opening for discharging a medium. The calculation routine of the computer program is used to ascertain an actual value of the volume of the medium discharged through the opening of the capillary in the target area by comparing data of the target area in the 3D reconstruction of the object region volume (22) and/or by comparing scanning information of the target area obtained by scanning the object region volume (22) using the OCT device (20) prior to and while discharging the medium. The invention also relates to a computer program and to a method for determining the volume of a medium discharged in an object region (18) through an opening by means of a surgical instrument with a capillary.

Claims

1. An arrangement comprising: an OCT device for scanning an object region volume in an object region by means of an OCT scanning beam; an item which has a section that is arrangeable in the object region volume and is localizable there by means of the OCT device; and a computer unit which is connected to the OCT device and which contains a computer program for determining a 3-D reconstruction of the object region volume and determining the relative position of the section of the item in the object region volume by processing OCT scanning information obtained by means of the OCT device by scanning the object region volume, wherein the computer program has a computing routine for determining a target area in the 3-D reconstruction of the object region volume, said computing routine determining a guide variable for the item in relation to the target area, the item being in the form of a surgical instrument which has a capillary with an opening for the release of a medium and the computing routine of the computer program serving to determine an actual value of the volume of the medium released into the target area through the opening of the capillary by comparing data of the target area in the 3-D reconstruction of the object region volume and/or by comparing scanning information of the target area obtained by means of the OCT device by scanning the object region volume before and during the release of the medium.

2. The arrangement as claimed in claim 1, wherein the computer program is configured to determine a 3-D reconstruction of the object region volume from data which are obtained by examining the object region volume using an imaging method by scanning the object region volume by means of the OCT scanning beam of the OCT device, and/or which are data determined presurgery and/or which are data relating to sensor signals for determining a position of the section of the item in the object region volume.

3. The arrangement as claimed in claim 1, wherein the computer program is designed to determine the relative spatial position of data in relation to one another by means of a registration method, said data comprising data from the following group: scanning information obtained by means of the OCT device by scanning the object region volume, the object region volume, data from further imaging methods, in particular optical image representations, Mill data, CT data, ultrasound images, endoscopy images, a position of the section of the item, data determined presurgery, position sensor signals.

4. The arrangement as claimed in claim 1, wherein: the OCT device is designed for successive continuous scanning of the object region volume by means of the OCT scanning beam and/or in that the OCT device is designed for successive continuous scanning of a region of the object region volume containing the section of the item by means of the OCT scanning beam; and/or the computer program is designed for successive continuous determination of the 3-D reconstruction of the object region volume and/or for successive continuous determination of the relative position of the section of the item in the object region volume; and/or the computer program is designed to determine a spatial target position for the item in the 3-D reconstruction of the object region volume; and/or the computer unit is connected to a memory for the provision during surgery of data determined presurgery; and/or the computer program is designed to determine target areas and/or spatial target positions in data determined presurgery and/or target areas and/or spatial target positions in the 3-D reconstruction of the object region volume by virtue of the application of methods for segmenting tissue structures and/or tissue layers; and/or in that the computer program contains a routine for generating a guide variable in the form of control signals for the item; and/or in that the computer program is designed to determine as a guide variable a spatial target position in the target area in the 3-D reconstruction of the object region volume taking account of characteristic features of the item and/or of a further item and/or of the target area in the 3-D reconstruction of the object region volume, and/or taking account of geometric relationships, in particular offset information, between these; and/or in that the arrangement comprises a device for visualizing the relative position of the section of the item in the 3-D reconstruction of the object region volume and/or for visualizing data determined presurgery and/or for visualizing the guide variable determined in relation to the target area and/or for visualizing variables derived from the guide variable; and/or in that the computer program generates acoustic, optical or haptic indication signals for the surgeon on the basis of the guide variable determined in relation to the target area and/or variables derived therefrom; and/or in that the computer program contains a shadowing routine for determining a corrected 3-D reconstruction of the object region volume, said shadowing routine recognizing regions that are shadowed by the item and specifying a compensation rule for the 3-D reconstruction of the object region volume in relation to these regions; and/or in that a marker that is localizable by the OCT scanning beam is arranged in the section of the item and/or in the object region; and/or in that the computer program contains a scanning routine for scanning the object region volume and/or the section of the item using specific scanning patterns and/or for adjusting a scanning rate, which scans the object region volume at a lower rate in comparison with the position of the section of the item; and/or in that the computer program is designed for adjusting the determination rule for the 3-D reconstruction and/or the determination rule for the relative position of the section of the item in the object region volume on the basis of a criterion.

5. The arrangement as claimed in claim 1, wherein OCT angiography data of the object region volume are generated from the scanning information obtained by means of the OCT device by scanning the object region volume.

6. The arrangement as claimed in claim 5, wherein the computer program is designed to determine the position and/or dimensions of blood vessels in the target area on the basis of the OCT angiography data, the computing routine of the computer program for determining the target area in the 3-D reconstruction of the object region volume taking account of the course and/or the position and/or the dimensions of the blood vessels in the target area.

7. The arrangement as claimed in claim 1, wherein the computer program contains a path planning routine which, on the basis of a criterion, calculates an optimal path of the item to the spatial target position.

8. The arrangement as claimed in claim 7, wherein the criterion is a measure of shadowing that quantifies the presence of shadows caused by the item in the calculated 3-D reconstruction.

9. The arrangement as claimed in claim 1, wherein the computer program contains a routine for determining a target area and/or a target position for the item in provided data determined presurgery and has a registration routine for registering the data determined presurgery with the 3-D reconstruction of the object region volume and a transfer routine for transferring the target area and/or the target position in the data determined presurgery to the 3-D reconstruction of the object region volume.

10. The arrangement as claimed in claim 1, wherein the computing routine of the computer program serves to determine as a guide variable a target value for the volume of the released medium by processing the target area in the 3-D reconstruction of the object region volume and/or by processing data determined presurgery and/or by processing OCT scanning information obtained by means of the OCT device by scanning the object region volume and/or by way of an input of a target value by a surgeon.

11. The arrangement as claimed in claim 1, wherein the computing routine of the computer program is designed to determine as a guide variable for a readjustment of the volume of the released medium a difference between a target value and an actual value of the volume of the medium released into the target area.

12. The arrangement as claimed in claim 1, wherein the computing routine of the computer program serves to determine as a guide variable the position of a substance to be removed and/or an amount of substance to be removed by processing the target area in the 3-D reconstruction of the object region volume and/or by processing data determined presurgery and/or by way of the input of a target value by a surgeon.

13. The arrangement as claimed in claim 12, wherein a visualization routine for visualizing the position of the substance to be removed and/or the amount of substance to be removed in the object region volume.

14. A computer program for determining a 3-D reconstruction of an object region volume in an object region and for determining the relative position of a section of an item in the object region volume by processing OCT scanning information obtained by means of an OCT device by scanning the object region volume, wherein a computing routine for determining a target area in the 3-D reconstruction of the object region volume and a guide variable for the item in relation to the target area, the item being in the form of a surgical instrument which has a capillary with an opening for the release of a medium and the computing routine serving to determine an actual value of the volume of the medium released into the target area by comparing data of the target area in the 3-D reconstruction of the object region volume and/or scanning information of the target area obtained by means of the OCT device by scanning the object region volume before and during the release of the medium.

15. A method comprising scanning, with an OCT device, an object region volume in an object region by means of an OCT scanning beam; providing an item, the item being in the form of a surgical instrument which has a capillary with an opening for the release of a medium and which has a section that is arrangeable in the object region volume and is localizable there by means of the OCT device; determining, by a computer unit which is connected to the OCT device and which contains a computer program, a 3-D reconstruction of the object region volume; determining a relative position of the section of the item in the object region volume by processing OCT scanning information obtained by means of the OCT device by scanning the object region volume; determining, by the computer unit, a target area in the 3-D reconstruction of the object region volume; determining, by the computer unit, a guide variable for the item in relation to the target area; and determine, by the computer unit, an actual value of the volume of the medium released into the target area through the opening of the capillary by comparing data of the target area in the 3-D reconstruction of the object region volume and/or by comparing scanning information of the target area obtained by means of the OCT device by scanning the object region volume before and during the release of the medium.

Description

[0056] Below, advantageous exemplary embodiments of the invention are described on the basis of the schematic drawings, in which:

[0057] FIG. 1 shows a first arrangement having a surgical microscope, having an OCT device for scanning an object region and having an item in the form of a surgical instrument in the form of an injection needle therein;

[0058] FIG. 2 shows a magnified view of the surgical instrument;

[0059] FIG. 3 shows a section of a portion of the retina;

[0060] FIG. 4 shows a transfer of a target area based on data determined presurgery to a 3-D reconstruction of an object region volume;

[0061] FIG. 5A, and FIG. 5B show image data relating to OCT-B-scans of an object region volume with inhomogeneities during the stem cell injection;

[0062] FIG. 6 shows a second arrangement having a surgical microscope, having an OCT device for scanning an object region, having an item in the form of a surgical instrument and having an image providing device;

[0063] FIG. 7 shows a third arrangement having a surgical microscope, having an OCT device for scanning an object region, having an item in the form of a surgical instrument and having a robotic unit;

[0064] FIG. 8 shows a fourth arrangement having a surgical microscope, having an OCT device for scanning an object region, having an item in the form of a surgical instrument, having an image providing device and having a robotic unit;

[0065] FIG. 9 shows an item in the form of an applicator for a further item in the form of a retinal pin;

[0066] FIG. 10A shows a front side of an implant for the retina;

[0067] FIG. 10B shows a back side of an implant for the retina;

[0068] FIG. 10C shows a magnified partial view of an implant having 3-D electrodes;

[0069] FIG. 11 shows a first image of an operating region in the eye interior of a patient's eye captured by means of a camera, having an applicator for a retinal pin and having an implant;

[0070] FIG. 12 shows a further image of the operating region in the eye interior of a patient's eye captured by means of a camera, having the applicator for a retinal pin and having the implant;

[0071] FIG. 13 shows an image of an operating region in the eye interior of a patient's eye captured by means of a camera, having a vitrectome for vitrectomy that produces a shadowed region;

[0072] FIG. 14 shows images of the ocular fundus of a patient's eye based on OCT angiography data for the visualization of blood vessels; and

[0073] FIG. 15 shows an image of an operating region in the eye interior of a patient's eye captured by means of a camera, having an implant and having blood flowing out of an injured blood vessel on the retina of the patient's eye.

[0074] The arrangement 10 shown in FIG. 1 contains a surgical microscope 16 for visualizing the object region 18 with magnification. By way of example, the surgical microscope 16 can be the OPMI® Lumera 660 Rescan surgical microscope by Carl Zeiss Meditec AG. The arrangement 10 comprises an OCT device 20 which provides an OCT scanning beam 21 for scanning the object region volume 22 with an A-, B- and C-scan at the patient's eye 14, as described, e.g., in chapter 3, pages 45 to 82 in A. Ehnes, “Entwicklung eines Schichtsegmentierungsalgorithmus zur automatischen Analyse von individuellen Netzhautschichten in optischen Koharenztomographie—B-Scans”, Dissertation, University of Giessen (2013).

[0075] The arrangement 10 comprises an item 24 in the form of a surgical instrument which has a section 84 that is arrangeable in the object region 18 and localizable in the object region volume 22 by means of the OCT device 20 on the basis of a marker 78.

[0076] The surgical microscope 16 comprises a stereoscopic observation beam path 38, 40, which facilitates the examination of the patient's eye 14 through a microscope main objective 42 in the object region 18. The surgical microscope 16 further comprises a zoom system 44 and an eyepiece 46. It comprises an illumination device 48 which illuminates the object region 18 with illumination light through the microscope main objective 42 for the purposes of stereoscopically visualizing the patient's eye 14 in the eyepiece 46.

[0077] The OCT device 20 provides the OCT scanning beam 21 with short coherent light, which is guided through the microscope main objective 42 to the object region 18 in an object region volume 22 by way of adjustable scanning mirrors 50, 52 and beam splitters 54 and 56. The light of the OCT scanning beam 21 scattered in the object region volume 22 returns at least in part to the OCT device 20 via the same light path. Then, the light path of the scanning light is compared in the OCT device 20 to a reference path. Using this, it is possible to detect the precise position of scattering centers in the object region 18, in particular the position of optically effective areas, with an accuracy which corresponds to the coherence length l.sub.c of the short coherent light in the OCT scanning beam 21.

[0078] In the surgical microscope 16, there is a device 58 for controlling the OCT scanning beam 21 and for setting the position of the object region volume 22 scanned by the OCT scanning beam 21 in the object region 18. The device 58 contains a computer unit 60. The computer unit 60 has an input interface 61 as a means for entering target values and contains a computer program for controlling the OCT scanning beam 21 and adjusting the spatial extent and position, i.e., the relative position and orientation, of the object region volume 22 scanned by the OCT scanning beam 21. The device 58 for controlling the OCT scanning beam 21 is embodied in this case for successive continuous scanning of the object region volume 22 and of the region of the object region volume 22 containing the section 84 of the item 24 by means of the OCT scanning beam 21. In this case, the OCT scanning beam 21 has a frame rate of 10 ms to 20 ms in order to allow the surgeon to have fast hand-eye coordination.

[0079] The device 58 for controlling the OCT scanning beam 21 contains a display unit 28, connected to the computing unit 60, in the form of a display for displaying a user interface, on which the object region volume 22 with the section 84 of the item 24, scanned on the patient's eye 14 by means of the OCT scanning beam 21 is able to be visualized on the basis of an image 64. Moreover, in the arrangement 10, the OCT scanning information for the OCT device 20 may be visualized for a surgeon in the eyepiece 46 of the surgical microscope 16 by means of a device for overlaying data 34.

[0080] The computer unit 60 connected to the OCT device 20 additionally generates indication signals by means of a signal generator 30. In the case of the stem cell injection, an indication signal produced by means of the signal generator 30 as an acoustic signal is generated when the injection location is reached. Moreover, a variable in the form of the amount of stem cells still to be injected, which is derived from the guide variable, is generated on the basis of a visual indication signal.

[0081] Further, the computer program in the program memory of the computer unit 60 contains a control routine which specifies the reference length for the OCT scanning beam 21 and the settings of the adjustable scanning mirrors 50, 52 for scanning the object region volume 22 in the object region with the patient's eye 14. There is a control member 62, actuatable by an operator, in the device 58 for setting the object region volume 22 scanned by means of the OCT scanning beam 21. The control routine moreover contains a scanning routine for scanning the object region volume 22 and the section 84 of the item 24 using specific scanning patterns. In the process, the object region volume 22 is scanned at a lower rate than the section 84 of the item 24 in order to keep the amount of data as small as possible and hence the computation time as short as possible.

[0082] The computer program in the program memory of the computer unit 60 moreover serves to determine a 3-D reconstruction 94 of the object region volume 22 and the relative position of the section 84 of the item 24 in the object region volume 22 by processing scanning information obtained by the OCT device 20 by scanning the object region volume 22. In this case, the OCT scanning information, the 3-D reconstruction 94 and the relative position of the section 84 of the item 24 in the object region volume 22 are determined in real time. Moreover, the computer program contains a calculation routine for determining a target area 90 in the 3-D reconstruction 94 of the object region volume 22. A guide variable for the item 24 is determined in relation to the target area 90. Here, in the present case, a guide variable is understood to be a variable which is determined by the computer program and which serves to guide the item 24 in the object region 18.

[0083] When injecting stem cells into the retina 15, a target value for the volume of the amount of a medium 88 in the form of stem cells that should be released by the injection needle is determined as a guide variable.

[0084] FIG. 2 is a magnified view of the item 24 in the form of a surgical instrument.

[0085] The surgical instrument is an injection needle for injecting stem cells in the retina 15 of the patient's eye 14. The injection needle has a section 84 which acts as an effective section and has a handle section 76 which can be held by a surgeon or, as an alternative thereto, by a micro-robot 70, too. The injection needle contains a capillary 86 and has a tip 80 with an opening 82 for releasing a medium 88 in the target area 90. There is a marker 78 that is localizable by means of the OCT scanning beam 21 at the injection needle.

[0086] It should be observed that the surgical instrument may also be in the form of an applicator for a retinal pin for placing an implant on the retina 15 of the patient's eye 14 or as a vitrectome for removing the vitreous humor from the patient's eye 14. It should moreover be observed that, in principle, the arrangement 10 can also be used for surgery on other body parts than a patient's eye 14.

[0087] FIG. 3 shows the structure of the retina 15 of the patient's eye 14, comprising blood vessels 108 as well as photoreceptors 112 and drusen 114.

[0088] FIG. 4 shows a transfer of a target area 90′ based on data 92 determined presurgery to a 3-D reconstruction 94 of an object region volume 22 in the computer unit 60. To determine a target area 90 and a target position 91 in the 3-D reconstruction 94 of the object region volume 22, data 92 of the object region 18 determined presurgery are combined by calculation in said 3-D reconstruction with a target position 91′ in a target area 90′. Here, the target position 91′ denotes a location in the data 92 determined presurgery that relate to the object region volume 22, at which the item 24 should carry out a certain function. When injecting stem cells, the target position 91′ in the target area 90′ in the data 92 determined presurgery corresponds to the envisaged location for the stem cell injection in the retina 15.

[0089] Methods for segmenting the tissue structures and tissue layers are applied for the purposes of determining the target position 91′ and/or the target area 90′ in the data 92 determined presurgery. Alternatively, the target position 91′ and/or the target area 90′ can also be marked by a surgeon in the data 92 determined presurgery.

[0090] The target position 91′ and/or the target area 90′ are transferred by the computer program from the presurgery data 92 of the object region volume 22 to the 3-D reconstruction 94 of the object region volume 22 determined from scanning information obtained by scanning the object region volume 22 and optionally from further data. In this case, a registration method serves for the transfer, said registration method mapping the target position 91′ in the target area 90′ in the data 92 determined presurgery to the target position 91 in the target area 90 of the object region volume 22. Alternatively, the surgeon can also directly mark the target position 91 and/or the target area 90 in the 3-D reconstruction 94 of the object region volume 22.

[0091] Then, the guide variable is determined by processing data of the target area 90′ in the data 92 determined presurgery or of the 3-D reconstruction 94 of the object region volume 22. When injecting stem cells, a guide variable is determined in the form of the amount of stem cells still to be released.

[0092] In this respect, FIG. 5A and FIG. 5B each show an OCT-B-scan of the object region volume 22 with stem cells released at a target position 21 in a target area 90, with the OCT-B-scans having injection inhomogeneities.

[0093] To monitor and control the amount of stem cells injected, an actual value of the volume of the amount of stem cells released at the target position 91 in the target area 90 of the object region volume 22 is determined by comparing OCT scanning information of the target area 90 obtained by the OCT device 20 by scanning the object region volume 22 before and during the release of the stem cells. In this case, the amount of stem cells injected is determined by means of image processing. To determine the volume change, it is possible for example to evaluate difference images which emerge as the difference of OCT scanning information item acquired at different times and/or the difference of 3-D reconstructions 94 determined at different times. Should the injected amount of stem cells contain particles visible to the OCT scanning radiation, difference images could also be used to determine, by way of image processing, the location of leakages in the object region volume 22. Leakages possibly present are taken into account by these measures and it is ensured that the specified amount of stem cells are in fact injected at the injection location. If necessary, the injection location, that is to say the target position of the injection needle, may also be adjusted during the stem cell injection.

[0094] On the basis of a target value for the amount of stem cells to be injected, specified by the surgeon, the guide variable in the form of the amount of stem cells still to be released is determined from the difference between target value and determined actual value of the amount of stem cells released. For readjusting the amount of stem cells, the computer program generates indication signals for a surgeon and/or control signals for the injection needle, which are transmitted to the control unit 72 of a micro-robot 70 guiding the injection needle, until the specified amount of stem cells are obtained at the target position 91 in the target area 90.

[0095] In this case, an indication signal is generated for the surgeon by the signal generator 30, said indication signal specifying the amount of stem cells still to be released or the amount of stem cells already released. The indication signal is represented in the form of a bar on the display of the display unit 28. On the basis of the signal, the surgeon can carry out the injection of stem cells themselves or monitor the injection procedure by the micro-robot 70.

[0096] FIG. 6 shows a second arrangement 10′ having a surgical microscope 16, having an OCT device 20 for scanning an object region 18, having an item 24 in the form of a surgical instrument and having an image providing device 65. To the extent the components and elements of the second arrangement 10′ shown in FIG. 6 correspond to the components and elements of the first arrangement 10 visible in FIG. 1, these have been identified with the same numbers as reference signs.

[0097] The image providing device 65 contains an image capturing device 66, by means of which images of the patient's eye 14 can be captured in real time. In addition or as an alternative thereto, the image providing device 65 contains a memory 63, in which data 92 determined presurgery that relate to the object region are provided. The images of the patient's eye 14 and the data 92 determined presurgery are used in addition to the data obtained by scanning the object region volume 22 by means of the OCT scanning beam 21 of the OCT device 20 in order to calculate the 3-D reconstruction 94 so as to obtain greater accuracy in the process. It should be observed that, in principle, biometric patient data may also be used when creating the 3-D reconstruction 94 of the object region volume 22, for example an eye length, an eye diameter, white-to-white, a corneal thickness, an anterior chamber depth or an anterior chamber angle.

[0098] A registration method is used for determining the relative spatial position of different data in relation to one another and for combining different data sources, said registration method processing scanning information obtained by the OCT device 20 by scanning the object region volume 22 and data 92 determined presurgery, target positions 91 for the items 24, 24′ and, if present, further data of the object region volume 22. This permits simultaneous use of all acquired data in every visualization of the object region volume 22.

[0099] FIG. 7 shows a third arrangement 10″ having a surgical microscope 16, having an OCT device 20 for scanning an object region 18, having an item 24 in the form of a surgical instrument and having a robotics unit 68. To the extent the components and elements of the third arrangement 10″ shown in FIG. 8 correspond to the components and elements of the first arrangement 10 visible in FIG. 1 or the components and elements of the second arrangement 10′ visible in FIG. 6, these have been identified with the same numbers as reference signs.

[0100] The robotics unit 68 comprises a micro-robot 70 with a control unit 72. By way of example, the micro-robot 70 can be in the form of a manipulator for surgical instruments with motor drives, as provided in the ophthalmic surgical operating system R1.1 by Preceyes B.V.

[0101] To ensure automation of the operation that is as comprehensive as possible, a movement of the item 24 embodied as a surgical instrument in the form of an injection needle is set in this case by means of the micro-robot 70. The micro-robot 70 of the robotics unit 68 is controlled in this case on the basis of the information items processed by the computer unit 60.

[0102] The control signals generated by the computer unit 60 for adjusting the micro-robot 70 in the robotics unit 68 are guide variables for the item 24, which is embodied as a surgical instrument in the form of an injection needle, in the third arrangement 10′″.

[0103] It should be observed that, in place of an item 24 embodied as a surgical instrument in the form of an injection needle, the micro-robot can in principle also move an item in the form of a surgical instrument embodied as an applicator or as a retinal pin or as a vitrectome in order to guide the item to a target area 90 in the object region volume 22. Offset information, which specifies the spatial offset of the section 84 of the item 24 from a spatial target position 91, can also be calculated to this end by the computer program on the basis of the target area 90 determined in the object region volume 22 and the determined relative position of the item 24. Then, control signals for displacing the item 24 are generated from the offset information and are transmitted to the control unit 72 of the micro-robot 70.

[0104] FIG. 8 shows a fourth arrangement 10′″ having a surgical microscope 16, having an OCT device 20 for scanning an object region 18, having an item 24 in the form of a surgical instrument and having a robotics unit 68, and having an image providing device 65. To the extent the components and elements of the fourth arrangement 10′″ shown in FIG. 9 correspond to the components and elements of the arrangements 10, 10′, 10″ which are visible in FIG. 1, FIG. 6 and FIG. 7 and described on the basis of these figures, these have been identified with the same numbers as reference signs. The image providing device 65 with the image capturing device 66 in this case facilitates, in turn, a calculation of the 3-D reconstruction 94 of a patient's eye 14 with an accuracy that is greater than a 3-D reconstruction which is based exclusively on scanning information obtained by means of an OCT device 20.

[0105] It should be observed that, during the vitrectomy by means of a surgical instrument also in the form of a vitrectome, the amount of vitreous humor to be removed from the respective point of the retina 15 may be specified as a guide variable in the arrangements described above.

[0106] It should moreover be observed that if the surgical instrument is also in the form of a vitrectome, an amount of vitreous humor to be removed from a patient's eye 14 can be indicated in the arrangements 10, 10′, 10″, 10′″ described above.

[0107] FIG. 9 shows an item 24 embodied as a surgical instrument in the form of an applicator for placing a further item 24′ in the form of a retinal pin, which serves to fasten a further item in the form of an implant to the retina 15.

[0108] FIG. 10A and FIG. 10B show an implant for the retina 15 of a patient's eye 14 as an item 24, said implant containing a power source 116 with a photovoltaic assembly and an image capture assembly 118. In this case, FIG. 10A is a perspective view of the implant in the case of a viewing direction directed at the side facing away from the retina. FIG. 10B is a perspective view of the implant in the case of a viewing direction on a side facing the retina of the patient's eye 14. FIG. 10C is a magnified partial view of the implant. The implant has 3-D electrodes 120, which penetrate into the retina 15 and interact with the neural network of the nerve tracts there.

[0109] In the apparatuses 10, 10′, 10″, 10′″ described above, the target position 91 of the envisaged location of attachment of the retinal pin to the retina 15 of the patient's eye and the actual position of the implant on the retina 15 can be displayed on the display unit 28 for the purposes of attaching an implant in a patient's eye 14.

[0110] FIG. 11 shows a first image of an operating region in the eye interior of a patient's eye 14 captured by means of a camera, said image containing a first item 24 in the form of an applicator for a retinal pin and containing a further item 24′ in the form of an implant just before the placement thereof on the retina 15. FIG. 12 shows a corresponding image of the operating region with the implant following the placement thereof on the retina 15. After the implant has been attached to the retina, the seat of the implant is verified by virtue of, e.g., the surgeon examining whether the implant fulfills its intended physiological function. When an implant is attached to the retina 15 of a patient's eye 14, a guide variable in the form of a control signal for the displacement of an applicator for attaching a retinal pin for fastening the implant is generated by the computer program and transmitted to the surgeon or the control unit 72 of the micro-robot 70.

[0111] FIG. 13 shows images 106 of the ocular fundus of a patient's eye 14 based on OCT angiography data for the visualization of blood vessels. In the above-described arrangements 10, 10′, 10″, 10′″, corresponding OCT angiography data can be generated from the scanning information obtained by the OCT device 20 by scanning the object region volume 22 and can be displayed on the display unit 28. The images 106 show the course of the blood vessels 108 in the object region 18. The position and/or the dimensions such as the diameter or the length of the blood vessels 108 is determined by the computer program on the basis of the images 106 that are based on OCT angiography data, for example by means of image processing. This information then is taken into account when determining the target positions 91 of the items 24, 24′ in the target area 90 in the 3-D reconstruction 94 of the object region volume 22. In particular, the number of blood vessels 108 to be punctured is minimized when determining a spatial target position 91 for an item 24, 24′ in the target area 90.

[0112] FIG. 14 shows an image of an operating region in the eye interior of a patient's eye 14 captured by means of a camera, having an implant and having blood flowing out of an injured blood vessel 108 on the retina 15 of the patient's eye 14.

[0113] OCT angiography data from the scanning information obtained by the OCT device 20 by scanning an object region volume 22 allow the prevention of hemorrhaging 110 as a result of injuring relatively large blood vessels 108 in the case of ophthalmic-surgical operations.

[0114] FIG. 15 is an image, captured by means of a camera, of an operating region in the eye interior of a patient's eye 14, in which an item 24 in the form of a vitrectome for vitrectomy is positioned, as a result of which a region 104 of the patient's eye 14 is shadowed. An exact vitrectomy without remains is important for the success of retinal implant surgery, as it facilitates an improved signal-to-noise ratio.

[0115] Hence, for the vitrectomy within the scope of an ophthalmic surgical operation by means of a vitrectome, the target position 91 of the latter in the target area 90 can be displayed on the display unit 28 in the above-described apparatuses 10, 10′, 10″, 10′″ as the location in the 3-D reconstruction 94 of an object region volume 22 where the vitreous humor should be removed.

[0116] Hence, the computing routine of the computer programs in the computer unit 60 of the above-described arrangements 10, 10′, 10″, 10′″ is designed for the vitrectomy by means of a vitrectome, in such a way that an amount of vitreous humor to be removed is determined as a guide variable by processing the target area 90 in the 3-D reconstruction 94 of the object region volume 22. Alternatively, the amount of vitreous humor to be removed can also be determined by processing data 92 determined presurgery or by the input of a target value by a surgeon. In this case, the vitreous humor is identified by injecting the triamcinolone marker, as is evident from FIG. 15, in order to facilitate a more accurate identification of the vitreous humor and hence a removal thereof without remainder where possible. In this case, the vitreous humor to be removed is visualized to the surgeon on the basis of a contour map which indicates for each point on the retina 15 the amount of the vitreous humor, located thereabove, to be removed. Moreover, during the vitrectomy, the computer program continuously indicates to the surgeon a boundary between the vitreous humor and a solution (BSS) for rinsing the object region 18. As a result, the amount of vitreous humor to be removed can be determined automatically by means of image processing and can be displayed in the visualization of the operating region by way of the display unit.

[0117] Further guide variables in the form of control signals for displacing the surgical instrument in the form of the injection needle or the vitrectome are generated both when injecting stem cells and when removing vitreous humor, and said further guide variables are transmitted to the surgeon or to the control unit 72 of the micro-robot 70.

[0118] FIG. 15 moreover shows a region 104 in an object region volume 22 that is shadowed by an item 24 in the form of a vitrectome. The computer program contains a shadowing routine to prevent the shadowing of regions in the object region volume 22. It identifies regions 104 shadowed by the item 24 and specifies a compensation rule for the 3-D reconstruction 94 of the object region volume 22 for these regions. In this case, the compensation rule provides for the replacement of the shadowed regions. OCT data of the same regions at other recording times, in particular OCT data just preceding the shadowing of the shadowed region 104, can be used both for identifying and for replacing the shadowed regions 104 in a 3-D reconstruction 94 shown in FIG. 15. As an alternative thereto, the shadowing routine for recognizing shadowed regions and/or for specifying the compensation rule may use the current 3-D reconstruction 94 and/or the currently recorded OCT data and/or data from other modalities relating to the same regions, for example optical data, MRI data, ultrasound images or CT data. Data 92 determined presurgery may also be used. Alternatively, the shadowed regions 104 may also be detected in the 3-D reconstruction 94 and may be replaced by data acquired from other regions outside of shadowed regions 104. Alternatively, the shadowed regions 104 may be detected in the data or in the 3-D reconstruction 94 and may be replaced by data generated by the computer program, for example by way of inpainting methods.

[0119] In an alternative embodiment, shadowing of regions is avoided by virtue of the computer program containing a path planning routine which, on the basis of a criterion, calculates an optimal path of the item 24 to the spatial target position 91 in the target area 90 of the object region volume 22. In this case, the path planning routine determines a measure of shadowing in the form of a value which quantifies the presence of shadows in the OCT data. If the light source position is known, the region 104 shadowed by the item 24 in the OCT data is calculated in advance for a certain path of the item 24 on the basis of the calculated relative position of the item 24. The measure of shadowing in this case denotes the magnitude of shadowing. On the basis of the measure of shadowing, the path planning routine then determines the shortest path of the item 24 to the target position 91 which does not exceed a threshold of the measure of shadowing. Alternatively, the path planning routine minimizes a criterion of the summation of the path length and the weighted measure of shadowing in order to determine a path which minimizes both the path length and the measure of shadowing to the greatest possible extent. The computer program contains a visualization routine for visualizing the optimal path of the item 24 for the surgeon using the display unit 28. In this case, planning the path for an item 24 to a target area 90 represents a guide variable.

[0120] It should be observed that both the input data of the 3-D reconstruction method and the input data of the registration method are adjusted where possible during the operation to the availability and the measurement accuracy of the provided data in order to obtain a greater accuracy for the 3-D reconstruction 94 of the object region volume 22. If the measurement accuracy of individual data points is too low, these are not taken into account by the respective method.

[0121] In summary, the following, in particular, should be noted: The invention relates to an arrangement 10, 10′, 10″, 10′″ comprising an OCT device 20 for scanning an object region volume 22, arranged in an object region 18, by means of an OCT scanning beam 21, comprising an item 24, which has a section 84 in the object region volume 22 that is arrangeable in the object region 18 and is localizable in said object region volume 22 by means of the OCT device 20, and comprising a computer unit 60 which is connected to the OCT device 20 and which contains a computer program for determining a 3-D reconstruction 94 of the object region volume 22 and determining the relative position of the section 84 of the item 24 in the object region volume 22 by processing OCT scanning information obtained by the OCT device 20 by scanning the object region volume 22, wherein the computer program has a computing routine for determining a target area 90 in the 3-D reconstruction 94 of the object region volume 22, said computing routine determining a guide variable for the item 24 in relation to the target area 90.

[0122] In particular, the invention relates to the aspects specified in the following clauses: [0123] 1. An arrangement (10, 10′, 10″, 10″) [0124] comprising an OCT device (20) for scanning an object region volume (22) in an object region (18) by means of an OCT scanning beam (21); [0125] comprising an item (24, 24′) which has a section (84) that is arrangeable in the object region volume (22) and is localizable there by means of the OCT device (20), and [0126] comprising a computer unit (60) which is connected to the OCT device (20) and which contains a computer program for determining a 3-D reconstruction (94) of the object region volume (22) and determining the relative position of the section (84) of the item (24, 24′) in the object region volume (22) by processing OCT scanning information obtained by means of the OCT device (20) by scanning the object region volume (22), [0127] characterized in that [0128] the computer program has a computing routine for determining a target area (90) in the 3-D reconstruction (94) of the object region volume (22), said computing routine determining a guide variable for the item (24, 24′) in relation to the target area (90). [0129] 2. The arrangement (10, 10′, 10″, 10′″) according to clause 1, characterized [0130] in that the computer program is designed to determine a 3-D reconstruction (94) of the object region volume (22) from data which are obtained by examining the object region volume (22) using an imaging method, in particular by scanning the object region volume (22) by means of the OCT scanning beam (21) of the OCT device (20), and/or which are data (92) determined presurgery and/or which are data relating to sensor signals for determining a position of the section (84) of the item (24, 24′) in the object region volume (22); [0131] and/or [0132] in that the computer program is designed to determine the relative spatial position of data in relation to one another by means of a registration method, said data comprising data from the following group: scanning information obtained by means of the OCT device (20) by scanning the object region volume (22), the object region volume (22), data from further imaging methods, in particular optical image representations, MRI data, CT data, ultrasound images, endoscopy images, a position of the section (84) of the item (24), data (92) determined presurgery, position sensor signals; [0133] and/or [0134] in that the OCT device (20) is designed for successive continuous scanning of the object region volume (22) by means of the OCT scanning beam (21) and/or in that the OCT device (20) is designed for successive continuous scanning of a region of the object region volume (22) containing the section (84) of the item (24, 24′) by means of the OCT scanning beam (21); [0135] and/or [0136] in that the computer program is designed for successive continuous determination of the 3-D reconstruction (94) of the object region volume (22) and/or for successive continuous determination of the relative position of the section (84) of the item (24, 24′) in the object region volume (22); [0137] and/or [0138] in that the computer program is designed to determine a spatial target position (91) for the item (24, 24′) in the 3-D reconstruction (94) of the object region volume (22); [0139] and/or [0140] in that the computer unit (60) is connected to a memory (63) for the provision during surgery of data (92) determined presurgery; [0141] and/or [0142] in that the computer program is designed to determine target areas (90′) and/or spatial target positions (91′) in data (92) determined presurgery and/or target areas (90) and/or spatial target positions (91) in the 3-D reconstruction (94) of the object region volume (22) by virtue of the application of methods for segmenting tissue structures and/or tissue layers; [0143] and/or [0144] in that the computer program contains a routine for generating a guide variable in the form of control signals for the item (24, 24′); [0145] and/or [0146] in that the computer program is designed to determine as a guide variable a spatial target position (91) in the target area (90) in the 3-D reconstruction (94) of the object region volume (22) taking account of characteristic features of the item (24) and/or of a further item (24′) and/or of the target area (90) in the 3-D reconstruction (94) of the object region volume (22), and/or taking account of geometric relationships, in particular offset information, between these; [0147] and/or [0148] in that the arrangement comprises a device for visualizing the relative position of the section (84) of the item (24) in the 3-D reconstruction (94) of the object region volume (22) and/or for visualizing data (92) determined presurgery and/or for visualizing the guide variable determined in relation to the target area (90) and/or for visualizing variables derived from the guide variable; [0149] and/or [0150] in that the computer program generates acoustic, optical or haptic indication signals for the surgeon on the basis of the guide variable determined in relation to the target area (90) and/or variables derived therefrom; [0151] and/or [0152] in that the computer program contains a shadowing routine for determining a corrected 3-D reconstruction (94) of the object region volume (22), said shadowing routine recognizing regions (104) that are shadowed by the item (24, 24′) and specifying a compensation rule for the 3-D reconstruction (94) of the object region volume (22) in relation to these regions; [0153] and/or [0154] in that a marker (78) that is localizable by the OCT scanning beam (21) is arranged in the section (84) of the item (24, 24′) and/or in the object region (18); [0155] and/or [0156] in that the computer program contains a scanning routine for scanning the object region volume (22) and/or the section (84) of the item (24, 24′) using specific scanning patterns and/or for adjusting a scanning rate, which scans the object region volume (22) at a lower rate in comparison with the position of the section (84) of the item (24, 24′); [0157] and/or [0158] in that the computer program is designed for adjusting the determination rule for the 3-D reconstruction (94) and/or the determination rule for the relative position of the section (84) of the item (24, 24′) in the object region volume (22) on the basis of a criterion. [0159] 3. The arrangement (10, 10′, 10″, 10′″) according to clause 1 or 2, characterized in that OCT angiography data (106) of the object region volume (22) are generated from the scanning information obtained by means of the OCT device (20) by scanning the object region volume (22). [0160] 4. The arrangement (10, 10′, 10″, 10″) according to clause 3, characterized in that the computer program is designed to determine the position and/or dimensions of blood vessels (108) in the target area (90) on the basis of the OCT angiography data (106), the computing routine of the computer program for determining the target area (90) in the 3-D reconstruction (94) of the object region volume (22) taking account of the course and/or the position and/or the dimensions of the blood vessels (108) in the target area (90). [0161] 5. The arrangement (10, 10′, 10″, 10″) according to any one of clauses 1 to 4, characterized in that the computer program contains a path planning routine which, on the basis of a criterion, calculates an optimal path of the item (24, 24′) to the spatial target position (91). [0162] 6. The arrangement (10, 10′, 10″, 10″) according to clause 5, characterized in that the criterion is a measure of shadowing that quantifies the presence of shadows caused by the item (24, 24′) in the calculated 3-D reconstruction (94). [0163] 7. The arrangement (10, 10′, 10″, 10″) according to any one of clauses 1 to 6, characterized in that the computer program contains a routine for determining a target area (90′) and/or a target position (91′) for the item (24) in provided data (92) determined presurgery and has a registration routine for registering the data (92) determined presurgery with the 3-D reconstruction (94) of the object region volume (22) and a transfer routine for transferring the target area (90′) and/or the target position (91′) in the data (92) determined presurgery to the 3-D reconstruction (94) of the object region volume (22). [0164] 8. The arrangement (10, 10′, 10″, 10″) according to any one of clauses 1 to 7, characterized in that the item (24, 24′) is in the form of a surgical instrument which comprises a capillary (86) with an opening (82) for the release of a medium (88). [0165] 9. The arrangement (10, 10′, 10″, 10″) according to clause 8, characterized in that the computing routine of the computer program serves to determine as a guide variable a target value for the volume of the released medium (88) by processing the target area (90) in the 3-D reconstruction (94) of the object region volume (22) and/or by processing data (92) determined presurgery and/or by processing OCT scanning information obtained by means of the OCT device (20) by scanning the object region volume (22) and/or by way of an input of a target value by a surgeon. [0166] 10. The arrangement (10, 10′, 10″, 10′″) according to clause 8 or 9, characterized in that the computing routine of the computer program serves to determine an actual value of the volume of the medium (88) released into the target area (90) by comparing data of the target area (90) in the 3-D reconstruction (94) of the object region volume (22) and/or scanning information of the target area (90) obtained by means of the OCT device (20) by scanning the object region volume (22) before and during the release of the medium (88). [0167] 11. The arrangement according to any one of clauses 8 to 10, characterized in that the computing routine of the computer program is designed to determine as a guide variable for a readjustment of the volume of the released medium (88) a difference between a target value and an actual value of the volume of the medium (88) released into the target area (90). [0168] 12. The arrangement according to any one of clauses 1 to 7, characterized in that the computing routine of the computer program serves to determine as a guide variable the position of a substance to be removed and/or an amount of substance to be removed by processing the target area (90) in the 3-D reconstruction (94) of the object region volume (22) and/or by processing data (92) determined presurgery and/or by way of the input of a target value by a surgeon. [0169] 13. The arrangement (10, 10′, 10″, 10′″) according to clause 12, characterized by a visualization routine for visualizing the position of the substance to be removed and/or the amount of substance to be removed in the object region volume (22). [0170] 14. A computer program for determining a 3-D reconstruction (94) of an object region volume (22) in an object region (18) and for determining the relative position of a section (84) of an item (24) in the object region volume (22) by processing OCT scanning information obtained by means of an OCT device (20) by scanning the object region volume (22), characterized by determining a target area (90) in the 3-D reconstruction (94) of the object region volume (22) and a guide variable for the item (24) in relation to the target area (90). [0171] 15. A method for determining a 3-D reconstruction of an object region volume (22) in an object region (18) and for determining the relative position of a section (84) of an item (24) in the object region volume (22) by means of a computer program according to clause 14.

LIST OF REFERENCE SIGNS

[0172] 10, 10′, 10″, 10′″ Arrangement/apparatus [0173] 14 Patient's eye [0174] 15 Retina [0175] 16 Surgical microscope [0176] 18 Object region [0177] 20 OCT device [0178] 21 OCT scanning beam [0179] 22 Object region volume [0180] 24, 24′ Item [0181] 28 Display unit [0182] 30 Signal generator [0183] 34 Data overlay [0184] 38, 40 Stereoscopic observation beam path [0185] 42 Microscope main objective [0186] 44 Zoom system [0187] 46 Eyepiece [0188] 48 Illumination device [0189] 50, 52 Scanning mirror [0190] 54, 56 Beam splitter [0191] 58 Device [0192] 60 Computer unit [0193] 61 Input interface [0194] 62 Control member [0195] 63 Memory [0196] 64 Image [0197] 65 Image providing device [0198] 66 Image capturing device [0199] 68 Robotics unit [0200] 70 Micro-robot [0201] 72 Control unit [0202] 76 Handle section [0203] 78 Marker [0204] 80 Tip [0205] 82 Opening [0206] 84 Section [0207] 86 Capillary [0208] 88 Medium [0209] 90 Target area [0210] 90′ Target area in data determined presurgery [0211] 91 Target position [0212] 91′ Target position in data determined presurgery [0213] 92 Data determined presurgery [0214] 94 3-D reconstruction [0215] 104 Shadowed region [0216] 106 Images based on OCT angiography data [0217] 108 Blood vessel [0218] 110 Hemorrhaging [0219] 112 Photoreceptors [0220] 114 Druse [0221] 116 Power source [0222] 118 Image capture assembly [0223] 120 3-D electrodes