ASSEMBLY FOR LASER TREATMENT OF OCULAR OPACITIES

Abstract

The assembly for laser treatment of ocular opacities consists of: a measurement system for obtaining depth information regarding ocular structures; a laser system; an eye-tracker unit; a display unit; and a control-and-operating unit. According to the invention, the control-and-operating unit is designed to determine, from the depth profiles, the depth of ocular structures relative to the depth of the laser focus, and, in particular for the retina and the capsular bag, to determine a blocked zone for the laser treatment. Furthermore, the control-and-operating unit is designed to generate, at least for the blocked zones of the retina and capsular bag and the laser focus, at least one tag in each case, the characteristic of which corresponds to the particular depth in the eye, in order to display these tags on the display unit and to overlay them with the live image. The invention relates to a partially automated therapy apparatus for laser treatment of ocular opacities in which two-dimensional views of the eye are combined with three-dimensional imaging from the measurement system.

Claims

1.-21. (canceled)

22. An arrangement for laser treatment of eye opacification, comprising: a measuring system that obtains depth information relating to eye structures; a laser system with optical elements that couple the measuring system and the laser system; an eye tracker unit; a display unit; and a control and operating unit; wherein the measuring system is configured to make available depth information relating to eye structures in the form of depth profiles; wherein the laser system is configured to comminute eye opacifications; wherein the eye tracker unit is configured to detect axial eye movements; wherein the display unit is configured to display at least one 2-D image representation of the eye as a live image; wherein the control and operating unit is configured to determine a depth of eye structures relative to a depth of a laser focus from the depth profiles and to determine at least one exclusion zone for laser treatment, the exclusion zone including at least one of a retina and a capsular bag, and wherein the control and operating unit is further configured to generate at least one marking that marks each of the at least one exclusion zones and marks the laser focus, characteristics of the at least one marking corresponding to a respective depth in the eye, and configured to display the markings on the display unit and to overlay the markings on the live image.

23. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to determine the depth of the eye opacification relative to the depth of the laser focus and to generate markers for the relative position of eye opacification in relation to the laser focus and to display these markings on the display unit.

24. The arrangement as claimed in claim 23, wherein the control and operating unit is configured to vary characteristics of the marking to be generated with regard to at least one of color, shape, numerical value of the depth and size.

25. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to generate the markings with depth-dependent size for the retina, the capsular bag, a lens, the laser focus or the eye opacification in such a way that the markings are arranged, centered around the lateral laser focus position.

26. The arrangement as claimed in claim 22, wherein the eye tracker unit is configured to compensate for axial eye movements.

27. The arrangement as claimed in claim 22, wherein the one 2-D image representation is an en face image representation of the posterior segment of the eye which is displayed as a live image with a refresh rate selected from a group consisting of 5 Hz, 10 Hz, and 20 Hz, and a latency selected from a group consisting of <200 ms, <100 ms and <35 ms.

28. The arrangement as claimed in claim 22, wherein the measuring system for obtaining depth information of the eye comprises an OCDR system.

29. The arrangement as claimed in claim 22, wherein anterior regions of the eye, selected from a group consisting of the capsular bag, a lens, a front surface of the cornea or back surface of the cornea, serve as a reference for the eye tracker unit.

30. The arrangement as claimed in claim 22, wherein a contact glass or a reference marking placed in the vitreous humor by laser treatment serves as a reference for the eye tracker unit.

31. The arrangement as claimed in claim 22, further comprising an OCDR system configured to record an A-scan and further comprising an image recording unit for making recordings of the fundus, with a position of the OCDR measuring beam in relation to the fundus being known through calibration.

32. The arrangement as claimed in claim 22, further comprising an OCT system configured to record a 3-D volume scan and wherein the eye tracker unit is configured to compensate for eye movements detected during the recording of the 3-D volume scan.

33. The arrangement as claimed in claim 22, wherein the display unit is configured to display further image representations, including the scan with the depth information of the eye, an overview of current settings, operating elements or a combination of the foregoing.

34. The arrangement as claimed in claim 22, wherein the display unit comprises a touch screen.

35. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to display on the display unit the markings generated for the exclusion zones of the retina and capsular bag and for the laser focus and to overlay these on the scan.

36. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to localize retinal landmarks, including at least one of a fovea, a macula, an optic nerve head and blood vessels, and to generate a marking for the retinal landmarks.

37. The arrangement as claimed in claim 23, wherein the markings generated by the control and operating unit differ in terms of color, structure or both.

38. The arrangement as claimed in claim 36, wherein the marking generated by the control and operating unit for a laser spot changes color, structure or both when the laser spot approaches one of the exclusion zones or the retinal landmarks.

39. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to warn the operator acoustically, optically or both when the laser focus approaches one of the exclusion zones or retinal landmarks.

40. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to switch off the laser system should the laser focus approach or enter one of the exclusion zones or retinal landmarks.

41. The arrangement as claimed in claim 22, wherein the control and operating unit is configured to assign different tolerances for switching off the laser system when the laser focus is approaching the two exclusion zones and the retinal landmarks.

42. The arrangement as claimed in claim 22, wherein the arrangement for laser treatment of eye opacification is integrated into a slit lamp.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The invention is described in more detail below on the basis of example embodiments. In the figures:

[0042] FIG. 1: depicts a fundus image with overlaid markings,

[0043] FIG. 2: depicts a fundus image with overlaid markings for different focal positions of the laser spot, and

[0044] FIG. 3: depicts a scan with markings for the exclusion areas and the laser spot.

DETAILED DESCRIPTION

[0045] The example arrangement for laser treatment of eye opacification arrangement for laser vitreolysis of vitreous humor opacification includes a measuring system for obtaining depth information of the eye, a laser system with deflection unit, optical elements for coupling the measuring and laser system, an eye tracker unit, a display unit, and a control and operating unit.

[0046] For example, the measuring system is designed to provide depth information of the eye in the form of scans. Axial eye movements are detected and compensated for by the eye tracker unit. The display unit is designed to display at least one 2-D image representation of the eye as a live image. Refresh rates of 5 Hz, for example 10 Hz, and in another example 20 Hz, and a latency <200 ms, for example <100 ms, and in another example <35 ms, are used for the live image.

[0047] According to an example embodiment of the invention, the control and operating unit is configured to determine the depth of eye opacification relative to the depth of the laser focus and to generate markers for the relative position of eye opacification in relation to the laser focus and to display these markings on the display unit.

[0048] Furthermore, the control and operating unit is configured to localize structures of the eye in the scans made available by the measuring system and to determine an exclusion zone for laser treatment, for example for the retina and the capsular bag.

[0049] For example, the control and operating unit is further configured to generate a marking for at least the exclusion zones of the retina and capsular bag and the laser spot, the size of which markings corresponds to the respective depth information in the eye, to display these markings on the display unit and overlay these on the live image.

[0050] By determining the position of the laser focus in relation to the eye structures to be protected exclusion zones generated for these eye structures, the physician is given the option of treating floaters manually. The generated exclusion zones prevent the laser focus from entering and damaging eye structures.

[0051] In accordance with an example embodiment, the control and operating unit further is configured to determine the depth of eye opacification relative to the depth of the laser focus and to generate markers for the relative position of eye opacification in relation to the laser focus and to display these markings on the display unit.

[0052] By additionally determining the position of eye opacification (floaters) in relation to the eye structures to be protected or in relation to the exclusion zones generated for these eye structures, there is the option of automatically treating floaters.

[0053] A manual treatment that is likewise still possible is simplified by virtue of the physician being able to at least approximately estimate the position of the laser focus in relation to the floaters.

[0054] In the arrangement presented herein, an OCDR or OCT system is used as the measuring system for obtaining depth information of the eye, said measuring system for example being combined with a YAG laser system with a deflection unit.

[0055] An A-scan and, with the aid of a further image recording unit, additional recordings of the fundus are recorded when an OCDR system is used, with the position of the OCDR measuring beam in relation to the fundus being known through calibration. The recordings of the fundus are for example recorded using IR or NIR illumination between 780 nm and 1060 nm.

[0056] In contrast thereto, a 3-D volume scan is recorded when the OCT system is used, with the eye movements being detected and compensated for by the eye tracker unit during the recording of the 3-D volume scan. Eye movement compensation is required because a 3-D volume scan acquisition may take up to 2 s and eye movements would cause the scans to be deformed.

[0057] While the eye structures can be detected relatively easily in the OCDR or OCT signals, the situation is different with floaters.

[0058] The identification is for example carried out in such a way that the scattering signal level of the vitreous humor is determined first. Structures which [0059] have signal values that are 2 dB, for example 5 dB higher than the average vitreous body signal, [0060] have a minimum axial size, for example >15 m in tissue or an equivalent optical path with an assumed refractive index of 1.36 and in the case of which signals still occur posteriorly at the level of the vitreous body or [0061] whose signal characteristics correspond to known floaters stored in a database, using size or position ratios, are identified as floaters. The eye tracker unit is designed to detect and compensate for the axial eye movements.

[0062] For example, the anterior regions of the eye serve as a reference, for example the capsular bag, lens or front or back surface of the cornea.

[0063] Since the retina can be more shadowed by floaters, it is not usually used as a reference. Therefore, more anterior eye regions are for example preferred for tracking the axial eye movement in relation to the floaters.

[0064] However, it is also possible for the contact glass or a reference marking placed in the vitreous humor by laser treatment to be used as a reference for the eye tracker unit. Should the contact glass be used as a reference, referencing in the form of a functional coating is conceivable to allow stable tracking.

[0065] According to the invention, the display unit is designed to display further image representations, for example the scan with the depth information of the eye and/or an overview of current settings and/or operating elements, in addition to a 2-D image representation of the eye as a live image. In this context, the display unit can be a touch screen.

[0066] According to example embodiments of the invention, binoculars, 3-D monitors, HMDs or the like are also provided as a display unit. Furthermore, the design of the control and operating unit is important to the invention. For example, it generates markings for the exclusion zones of the retina and capsular bag and the laser spot, in order to display these on the display unit and overlay them on the live image and/or scan. Even the floater itself can be provided with a marking in the process.

[0067] The control and operating unit is further developed to localize retinal landmarks, such as the fovea, macula, optic nerve head or else blood vessels, and to generate a respective marking for each of these in order to optionally also display these on the display unit and overlay these on the live image/and or scan.

[0068] To avoid injury, the laser treatment can be interrupted if the laser beam is aimed at one of the retinal landmarks.

[0069] Moreover, according to the invention, provision is made for local changes in the height of the retina to be monitored, for the purposes of which critical local points can likewise be marked, as described, in order to avoid stresses that could cause retinal detachments during a further laser treatment.

[0070] According to an example embodiment the invention, the markings generated by the control and operating unit differ in terms of color and/or structure.

[0071] In this respect, FIG. 1 shows the representation of a fundus image with overlaid markings, with both the fundus image and the markings being colored in reality. From outside to inside, the markings denote: capsular bag 1, anterior exclusion zone boundary 2, laser focus 3, floaters 4, posterior exclusion zone boundary 5, retina 6, and laser direction 7.

[0072] Furthermore, the marking generated by the control and operating unit for the laser spot changes its color and/or structure when the laser spot approaches one of the exclusion zones or retinal landmarks.

[0073] It is also possible to warn the operator acoustically and/or optically or switch off the laser system should the laser focus approach or enter one of the exclusion zones or retinal landmarks.

[0074] In this respect, FIG. 2 shows the representation of a fundus image with overlaid markings for different focal positions of the laser spot, with both the fundus image and the markings in this case also being colored in reality. In the fundus images depicted here, only the markings for the retina 6, the laser focus 3 and the capsular bag 1 are present for better clarity. While a laser treatment is possible in the top two figures because the laser focus 3 is located in the safe area between the retina 6 and capsular bag 1, a laser treatment is not possible in the two lower images, by contrast, because the laser focus 3 comes too close to the retina 6 or the capsular bag 1 and is located in the respective exclusion zone (not shown) in each case.

[0075] FIG. 3 shows the representation of a scan with markings for the exclusion areas and the laser spot. From this representation of the depth scan 9, the user can very quickly and reliably identify the depth at which the laser focus 3 is located in relation to the retina 6 and the lens 8 (or the capsular bag 1). Additionally, the posterior exclusion zone 5 and the anterior exclusion zone 2 are also depicted here.

[0076] Furthermore, the control and operating unit is designed to assign different tolerances for the approach to both exclusion zones and the retinal landmarks.

[0077] In an example embodiment, the arrangement for laser vitreolysis of vitreous humor opacification is integrated into a slit lamp. However, the concept proposed here for laser vitreolysis is likewise applicable in a similar way in the case of surgical microscopes.

[0078] The example arrangement is also suitable for displaying a type of treatment history, for example by marking and storing shot depths and shot positions. It is also possible to display the incremental change in position of floaters (as a trajectory) and also retinal portions when shooting incrementally with the laser (marking of local elevations).

[0079] Example embodiments of the invention make available an arrangement for laser treatment of eye opacification that eliminates the disadvantages of the known technical solutions and offers a possibility of combining 2-dimensional views of the eye with the 3-dimensional recordings of the measuring system in a simple way, thus easing the handling thereof for the operator. Moreover, the solution is easy to implement and economically cost-effective, and enables a simpler, faster, and, above all, safer treatment of bothersome vitreous humor opacification by way of laser vitreolysis.

[0080] According to example embodiments of the invention, the depth information with regard to the position of sensitive eye structures, the laser focus, and the possibly also moving floater to be processed obtained from OCDR or OCT systems are processed in such a way that they can be combined with the 2-D view familiar to the physician in an intuitively processable manner.