The invention relates to an ophthalmologic device for examining an eye as well as to a method for operating an ophthalmologic device for examining an eye.
In ophthalmology, a patient's eye is investigated by means of a device having a microscope. Modern devices comprise cameras that allow to record images viewed through the microscope. They also comprise a storage device for storing the images.
JP 2016209453 describes a device where some parameters under which the images are taken are recorded for documentation.
The problem to be solved by the present invention is to provide a device and method of the type mentioned above that allow a versatile analysis of the eye.
This problem is solved by the device and method of the independent claims.
Accordingly, the device for examining an eye comprises at least the following elements:
a) A plurality of images from the camera, i.e. recorded by the camera.
b) Attributed imaging parameters for these images. The “attributed image parameter(s)” for a given image is/are descriptive (i.e. provide information on) of at least one recording condition of the given image.
In another aspect, the invention is implemented as a method for operating an ophthalmologic device for examining an eye, wherein the ophthalmologic device comprises a microscope, a camera positioned to record an image through the microscope, and a storage device as mentioned above. The method comprises at least the following steps:
In such a device and method, it is possible to provide one or more “desired imaging parameters” and then to search the stored images in the storage device based thereon. Hence, it becomes possible to search for images that were recorded under given imaging parameters (or parameters similar to them).
Advantageously, the device may comprise at least one current state monitor for determining at least one “current imaging parameter” of the device. This state monitor may e.g. be connected to at least one detector for detecting a setting of the device, and/or it can monitor the movement of actuators in the device and/or it can process the image recorded with the camera.
This e.g. allows to automatically use said current imaging parameter(s) as an attributed image parameter for an image recorded by the camera. In this case, the control unit may be adapted and structured to generate the “attributed imaging parameter(s)” from the current imaging parameter(s).
Also, the device can be adapted to use the current imaging parameter(s) to search the storage device for images that match them, at least to some degree. In this case, the search unit may be adapted and structured to generate the “desired imaging parameter(s)” from the current imaging parameter(s).
In one aspect, the method may comprise the following steps to be carried out during an examination of the eye:
This allows generating a rich record of the state of the eye for differing imaging parameters at a given point in time. This record may later be recalled. For example, if the examiner detects a feature of interest in a given part of the eye in a future examination, she/he can retrieve earlier images of the same part in order to examine if that feature was present in the past.
It must be noted that the control unit of the device may be adapted to carry out the method steps of the invention by being programmed to do so. Hence, any method steps can also be formulated as the control unit being adapted to carry out said method steps.
In an advantageous embodiment, the device can comprise a slit lamp microscope.
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. This description makes reference to the annexed drawings, wherein:
Device
The shown device comprises an optical apparatus A and a computer B.
Optical apparatus A has a base 1 resting e.g. on a desk, a horizontally and vertically displaceable stage 2 mounted to base 1, a first arm 3, and a second arm 4.
The arms 3 and 4 are mounted to stage 2 and pivotal about a common vertical pivot axis 5.
Advantageously, arms 3 and/or 4 are manually operated, i.e. their angular position is changed manually, and they are not equipped with electric actuators. They may, however, also be provided with electric angular actuators to operate them automatically.
The device may further include a headrest 7 mounted to base 1 for receiving the patient's head.
Arm 3 carries a microscope 8, and arm 4 carries a first illumination source 9.
First illumination source 9 may e.g. be a conventional slit lamp as known to the skilled person, adapted to project a slit-shaped light beam onto the eye 10 to be examined.
Microscope 8 has an optical axis 12. It may comprise an entry objective 14, which projects an image of eye 10 onto a camera 16 and/or an eyepiece 18.
Microscope 8 may be provided with changeable zoom optics 15 for changing the optical magnification. Changeable zoom optics 15 may include continuously changeable zoom optics or stepwise changeable zoom optics (e.g. implemented as a Galilean optical system).
For quantitative measurements, the device advantageously is equipped with camera 16, while eyepiece 18 is optional. A beam splitter 20 may be arranged to spilt light between these components.
A plurality of microscope light sources 22a, 22b may be arranged on microscope 8 and movable together with it. They form a second illumination source 22. Advantageously, they are located around entry objective 14 and/or on a side of microscope 8 that faces eye 10.
Advantageously, the microscope light sources 22a, 22b are LEDs. They may, however, also be other types of light sources, e.g. semiconductor lasers.
Advantageously, the microscope light sources 22a, 22b may include infrared light sources 22a with a wavelength of at least 700 nm as well as visible light sources 22b with a shorter wavelength, e.g. a wavelength of less than 500 nm. Alternatively, the visible light sources 22b may e.g. emit green, red, or white light.
While first illumination source 9 is pivotal in respect to microscope 8, second illumination source 22 is fixed in respect to microscope 8.
First illumination source 9 comprises a light source 30, a modulator 32 and imaging optics 34.
Light source 30 can e.g. comprise several units emitting different wavelengths, e.g. in the red, green, blue, and infrared range of the optical spectrum. These units can be controlled separately in order to change the color of light source 30.
Modulator 32 is a spatial light modulator defining the cross section of the beam generated by first illumination source 9. It may e.g. be one of the solutions described in U.S. Pat. No. 5,943,118, such as a liquid crystal display or a controllable micro-mirror array.
Imaging optics 34 projects the light from modulator 32 onto the anterior surface of eye 10, e.g. via a mirror 36 mounted to arm 4.
Illumination source 9 can be arranged above or below mirror 36.
The device further comprises a control unit. In the present embodiment, said control unit is implemented in part in optical device A, e.g. as a microprocessor, and in part in computer B remote from optical device A. This will be described in more detail below.
The device may further comprise a number of detectors:
The components located in optical apparatus A and in computer B are enclosed with dotted lines labeled accordingly. A suitable interface 50 with interface circuits 52a, 52b connects these two parts. Interface 50 may be wire-bound or wireless.
Optical apparatus A comprises a control unit 24, such as a microprocessor with program control, which is connected to the various detectors 40a, 40b, etc. It is also connected to camera 16 for recording images and to the first and second illumination sources 9, 22 for controlling them.
Computer B also comprises a control unit 56, such as a microprocessor with program control, which is connected by means of driver circuitry to a display 58 as well as an input device 60. Input device 60 may e.g. be a keyboard and/or a touch-interface on display 58.
Computer B also comprises a storage device 68 for storing image and/or video data as well as other data as described in more detail below.
In the following, various scenarios while operating the device are described.
Device Operation
In a first step 70, the examiner specifies the client being examined by entering a unique specifier into the device, e.g. by means of input device 60. This specifier may e.g. be a unique patient ID.
The examiner may also enter an identifier descriptive of the examination to be carried out.
Also, the examiner enters the eye to be examined, i.e. if he is about to examine the left or right eye. Alternatively, this information may be derived from the x-position of the microscope.
The device, e.g. computer B, will retain this information in its storage, e.g. by storing the patient ID, an examination specifier, and a left-right-eye indicator.
In a next step 72, the device may optionally be centered on the patient's eye. For example, the examiner can view the image recorded by microscope 8, e.g. through eyepiece 18 or as a life image of camera 16 on display 58, and adjust the microscope along the directions x and y until the eye's pupil is in its center. Also, the optical axis 12 of microscope 8 is brought into its angular center position, i.e. arm 3 is pivoted to align optical axis 12 with direction z.
Once this position is established, the examiner confirms proper alignment of the device by e.g. operating a control on optical apparatus A or computer B.
Starting from this moment, the device knows how microscope 8 is arranged in respect to the eye.
The device will now start to automatically record a series of individual images, e.g. a video feed, by means of camera 16.
Concurrently, the examiner will change the settings of the device in order to investigate one or more specific parts of the eye, step 74. For example, the examiner may offset the microscope along x, y, and/or z, change the viewing angle of the microscope, and/or change its magnification factor.
The device monitors and records these changes of the settings, i.e. it determines the “current imaging parameters”, e.g. in control unit 24. The current imaging parameters are sent to computer B together with the series of images, such that a set of imaging parameters can be attributed to each image.
Computer B stores the images and their “attributed imaging parameters” in storage device 68, step 76.
In the course of the examination, the examiner may explicitly chose to select some images, e.g. for a report, by entering a command in optical apparatus A or computer B. However, the device will not only store these selected images, e.g. marking them as “selected”, but the whole series of images for later retrieval.
When examination is complete, step 78, the examiner may specify this, e.g. again by means of input device 60. At this point, the automatic recording of images in storage device 68 may be terminated.
Hence, in the course of an examination, the device records a large number of images and stores them with their attributed imaging parameters in storage device 68, together at least with the patient ID.
Hence, in more general terms, the present method may contain the steps of
This allows to store, for every image, the relative location of the optical axis 12 in respect to the eye.
In another aspect, the method comprises at least the following steps:
In this way, the device automatically stores a record of a large number of images, taken for N different imaging parameters in storage device 68. Advantageously, the number N is much larger than 1, e.g. 10 or more, during a single examination.
The images in storage device 68 may be stored as individual images. Alternatively, they may be stored as one or more video sequences, with at least some of the images stored as single frames of these video sequences, which may be a more compact form of storage.
For any such video sequence, the attributed image settings may change between frames. Hence, advantageously, storage device 68 holds, for at least some of the video sequences, parameter sequences describing how the attributed imaging parameters of the images change over said video sequence.
Image Retrieval
The device is equipped with a search unit 80, which is shown schematically as a functional block in
As mentioned above, search unit 80 is adapted and structured to retrieve, from storage device 68 and given at least one “desired imaging parameter”, one or more matching images.
For example, the examiner may see a feature of interest in the eye during examination and be interested to see older recordings of the same part of the eye, e.g. in order to view how an abnormality has developed over time. He then can use search unit 80 to retrieve older records of the same part of the eye.
To do so, he may e.g. use the current imaging parameters of the device, such as the current position of the camera and the current zoom factor, and automatically transfer them to search unit 80, which then searches storage device 68 for older images with the same or similar attributed imaging parameters.
When such matches are found, the corresponding images 86a may e.g. be shown in a part 88 of display device 58, each of them with additional information 86b. Such additional information may e.g. be a time of recording of the image as well as, optionally, one or more of its attributed imaging parameters.
In the above example, the “desired” imaging parameters fed to search unit 80 are at least some of the current imaging parameters of the device.
Alternatively, or in addition thereto, the desired imaging parameters fed to search unit 80 may be generated as follows:
The device may also comprise an image processor 90, which is shown as a functional unit in
Image processor 90 is able to identify, in an image recorded by camera 90, the subsection of the eye shown therein, e.g. it can recognize the “scene” visible in the camera. For example, given an image as shown in part 82 of
These parameters, termed “subsection description”, describe the part of the eye visible in the image. As such, they are imaging parameters as mentioned herein. This subsection description can e.g. be used for the following applications:
a) It can be stored as attributed imaging parameters (or parts of the attributed imaging parameters) with the image they have been obtained from.
b) It can be fed to search unit 80 as “desired imaging parameters” in order to search storage device 68.
Hence, in more general terms, the method may comprise the following steps:
Image processor 90 may operate concurrently with the recording of the images by means of camera 16 and feeding them to storage device 68.
Alternatively, the images can first be stored in storage device 68 and image processor 90 may process them at a later time. This provides more time and requires less computing power for processing and properly indexing the images.
Imaging Parameters
As mentioned, the invention relates to the use of imaging parameters of the device for storing these parameters together with the images (attributed imaging parameters) as well as for searching images (desired imaging parameters) as well as for describing the current setup and use of the device (current imaging parameters).
These imaging parameters may include one or more of the following parameters:
As mentioned, the imaging parameters may include at least one setting of the illumination system 9, 22 of the camera, which comprises the first illumination system 9 (the slit lamp) and the second illumination system 22 (the light sources 22a, 22b) mounted to microscope 8. Such parameters may include:
In order to determine the current imaging parameters, the device comprises a current state monitor 92, which may be incorporated in optical apparatus A, e.g. as a part of the software of control unit 24. Current state monitor 92 is able to determine the current imaging parameters of the device. It may do so by cooperating with the detectors 40a, 40b . . . . In addition thereto, or alternatively thereto, it may also be able to determine at least part of the current imaging parameters by monitoring the state of the device, e.g. the state of the stepper motors or other actuators in the device that change the settings, e.g. by monitoring actuators for displacing stage 2 in respect to base 1. It may also cooperate with image processor 90 for extracting at least part of the current imaging parameters from an image taken by camera 16.
Matching Imaging Parameters
The algorithm used by search unit 80 for identifying the images whose attributed imaging parameters best match the desired imaging parameters as well as for ranking them may depend on the type of imaging parameters. The following are some advantageous criteria assuming that the respective parameters are part of the imaging parameters:
Search unit 80 may be configurable to use certain of these criteria and/or to ignore certain of these criteria.
Notes
In
Also, part or all of the computing and storage functionality, and in particular storage device 68, may also be located at a remote site, such as on a remote server accessible e.g. through the internet.
To summarize, in one embodiment, the invention describes an ophthalmologic device that comprises a microscope 8, an illumination system 9, 22, a camera 16 positioned to record an image through said microscope, and a storage device 68. When examining an eye, camera 16 may be operated to continuously record a series of images. The images are stored in storage device 68, each one with attributed imaging parameters describing the recording conditions of the image. When the examiner wants to retrieve images taking under examining conditions similar to the one presently used, the device is able to automatically retrieve the closest matches from storage device 68. This allows to record, in the background, a large number of images documenting an eye's history and to retrieve them efficiently.
While there are shown and described presently preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2019/063348 | 5/23/2019 | WO | 00 |