Device and system for initiating an entoptic phenomenon that can be perceived by a patient

Abstract

The invention relates to a device (1) for initiating an entoptic phenomenon that can be perceived by a patient, a system with a device (1) of this type, as well as a data processing unit (12) which provides the patient with information relating to the use of the device and with a functional status of their retinal vessels in a targeted manner. The device (1) according to the invention is characterised in that a housing (4) is provided with a contact surface (6) which can be placed on the head (8) of the patient in the region of the eye (7) in such a way that light emitted by the lamp unit (5) falls at least partially onto the retina (2), wherein the lamp unit (5) is designed to emit light at different times and along different beam paths in such a way that the emitted light falls in different points on the retina (2) when the contact surface (6) is in place.

Description

[0001] Device and system for initiating an entoptic phenomenon perceivable by a patient

[0002] The invention relates to a device for initiating an entoptic phenomenon perceivable by a patient. Furthermore, the invention relates to a system comprising such a device and a data processing unit that provides the patient with targeted information regarding the use of the device and the functional status of their retinal vessels. The described device comprises a handle and a housing in which a lighting unit is arranged and which has a contact surface so that the device can be placed on the patient's head in the area of ​​the eye and precisely aligned.

[0003] Various methods are known in the art that enable non-invasive, indirect observation of retinal vessels, particularly the Purkinje vein pattern and macular achilles, by triggering entoptic perception. The main application of the aforementioned methods is the early detection and monitoring of diabetic retinopathy and the assessment of postoperative visual acuity in cases of media opacities.

[0004] The entoptic Purkinje tree test can be used to observe the retinal blood vessels of one's own eye. During normal vision, the shadows cast by the retinal vessels are not perceived due to local adaptation. However, light projected into the eye through the sclera, bypassing the optical system, creates briefly perceived shadows of the retinal vessels on other retinal receptors. Figure 5 shows a sketch of the "Purkinje tree" in this context. This entoptic image creates an image of the retinal vessels, which, however, quickly fades if the light source is not moved. The vessels are perceived as a magnified image representing a complex and branched vascular tree, the "Purkinje tree." Figure 5 also shows the unique structure of the avascular macula with its so-called macular ochre.Macular chagrin is perceived by the patient as numerous glittering points of light in the avascular region of the retina. These points of light are created when a spot of light is moved across the sclera parallel to the limbus and are presumably caused by light reflections at the boundary surfaces of the foveal cone mosaic. Macular chagrin allows for a qualitative assessment of macula function. Purkinje vein pattern is an entoptic phenomenon that consists in the perception of the retinal vein pattern as a shadow on the retina. The vein pattern is observable when a small light source is moved back and forth across the sclera parallel to the limbus. The retinal blood vessels are normally not subjectively perceptible because their shadow image on the retina is stationary and thus erased by local adaptation.If the light source is moved, the retinal vessels are imaged at different retinal locations, preventing local adaptation. The Purkinje vein pattern can also be perceived in cases of media opacities in the cornea and lens.

[0005] The principles of entoptic perception of retinal vessels are generally well known and described in detail in the scientific literature.

[0006] Important for the described technical solution for self-examination of the functional status of retinal vessels is that in diabetic patients, the progression of diabetes should be determined by observing the vascular supply to the eye at regular intervals. If the examination is performed by an ophthalmologist, ophthalmoscopic assessment of the retina is available as the gold standard, at least provided there is no media opacification, such as cataracts, in the eye. In addition to visual acuity, monitoring diabetic retinopathy is important for the detection of cardiovascular diseases. Especially in type 1 and type 2 diabetes patients, an increased risk can be assumed if it is determined that the retinal vessels exhibit only a few microaneurysms.However, diabetes patients only notice the development of their microangiopathy very late, since involvement of the center of the retina, which is responsible for reduced visual acuity, only occurs late in the course of the disease.

[0007] Based on the above, it would be desirable that a reliable examination of the retinal vessels could be carried out at shorter intervals, in a comparatively simple and cost-effective manner and, particularly with regard to medical care in many developing or emerging countries, without the presence of an ophthalmologist during the examination being necessary.

[0008] Clinically, entoptic perception of the retinal vessels and macular chagrin is used to assess the functional status of the retina when severe opacities of the light-refracting media, such as the cornea, lens, or vitreous humor, are present. In this context, it is known to test potential vision by placing a bright penlight with a point light source directly into the patient's open or closed eye and moving it up and down at a frequency of approximately 5 Hz. During the movement, the illumination is either transscleral with the eyelid open or transpalpebral through the closed eyelid. To date, process parameters such as frequency, holding angle, or contact pressure have been varied by questioning the patient until the retinal vessels and possibly even the macular chagrin can be perceived by the patient.Alternatively, the moving light spot is generated using a light fixture in which the patient's head is fixed. Following the initiation of entoptic perception by the patient, the physician questions them about their observations and describes what they see or have seen. A disadvantage of these conventional examination methods is that simple self-diagnosis is largely impossible.

[0009] Furthermore, the reproducibility of the examination results is often severely limited and depends on the experience and skills of the people involved, both the physician and the patient. Furthermore, the induced vascular image is no longer recognizable after a few seconds, making quantitative examination impossible.

[0010] A device designed to automatically initiate entoptic perception is known from WO 91 / 16857 A1. The device described features a holder for the patient's chin or forehead, which is designed to ensure reliable head fixation during the examination. As soon as the head is in the fixed position, a light spot is automatically moved over the open or closed eye, thus triggering entoptic perception in the patient. Once again, the patient describes the structure and appearance of the retinal vessels to the physician as they appear to him.

[0011] Nevertheless, the success of a self-examination and the entoptic perception of retinal vessels, both with manual and automated light spot guidance, depends heavily on the interaction between physician and patient. In this case, the patient has only limited or no control over the quality of the image, and a stabilized image on which the patient focuses to describe their retinal vessels cannot be generated using the known methods. Based on the technical solutions known from the prior art and the problems described above, the invention is based on the object of creating a handy and easy-to-use device that enables a patient to trigger a reproducible, entoptic perception of their retinal vessels and thus perform a reliable self-diagnosis of the functional status of the retina.The device should be simple to operate and require as few steps as possible from the patient. Using the device to be specified, it should be relatively easy for a patient to generate a moving light spot on their own retina and thus obtain reproducible results. Furthermore, the device should be reliable and easy to operate by the patient themselves, without the need for an ophthalmologist.

[0012] Furthermore, a system should be specified into which a device that solves the aforementioned tasks can be easily integrated, ensuring both the generation of entoptic perception and patient support in performing a self-diagnosis to determine the functional status of their own retina. The system should be designed in such a way that a patient can be provided with comparatively simple assistance both in operating the device and in evaluating the perceived retinal vascular structures. The system used should, in turn, be usable by the patient without the need for the presence of a physician for proper use.

[0013] It is essential that, on the basis of an entoptic perception of the vascular structures of the retina, a reliable self-diagnosis of the functional status of the retinal vascular structure is possible in a simple manner and without the need for special equipment, and at the same time, changes can be detected quickly and easily so that the patient can consult an ophthalmologist in such a case as soon as possible.

[0014] The above-described object is achieved with a device according to claim 1 and a system according to claim 8. A suitable data processing system for a system for performing a self-diagnosis of the functional status of the retinal vessels is specified in claim 11. Advantageous embodiments of the invention are the subject of the dependent claims and are explained in more detail in the following description, with partial reference to figures. The invention relates to a device for initiating an entoptic phenomenon on the patient's retina that is perceptible by a patient, comprising a handle and a housing in which a lighting unit is arranged.According to the invention, the housing has a contact surface that can be placed on the patient's head, in particular on the closed eyelid, in the area of ​​the eye in such a way that light emitted by the lighting unit falls at least partially on the retina, wherein the lighting unit is configured to emit light at different times along different beam paths in such a way that the emitted light strikes the retina at different points in time when the contact surface is placed on it. The invention is thus essentially characterized in that a light spot can be produced at at least two different locations on the patient's retina using the lighting unit. In relation to the device, this means that the lighting unit emits light along at least two different beam paths, which are arranged or run differently relative to the contact surface and the housing of the device.At the same time, the lighting unit is configured in such a way that the housing, which is connected to the handle that can be grasped by the patient, does not have to be moved in order to emit light along the at least two differently arranged beam paths and thus to generate a light spot at least in two locations on the patient's retina. It is therefore essential for the invention that it is possible for a patient to place the housing of the device, in particular a handheld device, on their head in the region of the eye, with the contact surface preferably enclosing at least part of the eye to be examined, and to generate a light spot on the retina which appears to the patient as a moving light spot, without the patient themselves having to move the housing or the device.

[0015] In principle, it is conceivable in this context that the lighting unit is designed to generate light spots at different locations on the retina using a plurality of light sources that can be specifically switched on and off, and / or that it has a drive for moving a light source or an optical element, in particular a mirror, in order to generate a movable light spot and apply it to the retina at at least two different locations. In both cases, it is again not necessary to move the device itself and its housing in order to generate a light spot sequentially at at least two locations on the retina. The invention therefore provides a device with which it is possible for a patient to trigger an entoptic perception of their own retinal vascular structure in a simple, reliable and reproducible manner.A particular advantage of the device according to the invention is that the patient can place the device himself on the eye to be examined and can intuitively vary, for example, the contact pressure and angle of incidence of the light emitted by the light source as needed, without the need for additional adjustment steps.

[0016] According to a particular embodiment of the invention, the lighting unit has a plurality of light sources that can be selectively switched on and off, or are selectively switched on and off, to generate a light spot at different locations on the patient's retina, which the patient perceives as a moving light spot. The at least two light sources are arranged as needed within the housing in the area of ​​the lighting unit.

[0017] Alternatively or additionally, it is conceivable to generate a light spot and / or light spots that are movable or moved relative to the retina at at least two locations on the retina by providing at least one servomotor for the controllable movement of the at least one light source and / or a deflection mirror for deflecting a light beam emitted by the light source. The device according to the invention is advantageously designed such that the light spot generated on the retina of a patient at least temporarily successively at at least two locations has a diameter of 0.5-3 mm in the region of the eye after the housing is placed on the patient's head.

[0018] According to a particularly suitable embodiment of the invention, focused light sources or light sources followed by optical elements for focusing, such as suitable lenses, are used to generate the at least one light beam.

[0019] It has further been shown that it is advantageous for a patient if light spots lying on a circular path on the retina, or a light spot moving along an at least almost circular path across the patient's retina, are generated successively or at least simultaneously for a short time. In order to generate a light spot that is perceived by the patient as a light spot moving along an at least almost circular path on the retina, the light source provided according to the invention has a plurality of light sources and / or suitable movement means are provided to specifically direct a light beam along different beam paths onto the patient's retina.In a particular embodiment, at least one servo motor and / or a movable deflecting mirror is provided to direct the light beam generated by a light source of the lighting unit in a circular movement over the retina, so that it appears to the observer as if the light spot is moved in a circular movement over the retina.

[0020] According to an alternative embodiment of the invention, the lighting unit has a plurality of light sources arranged in a circle or at least approximately in a circle in the housing. If these circularly arranged light sources are switched on and off one after the other, the patient perceives a light spot moving in a circle across the retina. In a particularly advantageous manner, the individual light sources are switched on and off in such a way that a so-called fading effect is achieved, whereby a transition of the light phenomena of the individual neighboring light sources occurs. In this case, a light source is only completely switched off after a neighboring light source has already been switched on. It is also conceivable that the intensity of the light radiation emitted by the individual light sources is varied in a temporal overlap region between the switching on and off of the individual light sources.In this context, it may be advantageous if the intensity of the light emitted by a light source is slowly increased after switching on and / or slowly decreased before switching off.

[0021] Furthermore, a specific embodiment of the invention provides for a plurality of light sources of a lighting unit to be arranged in a row. Such a row-like arrangement of various light sources can be provided as an alternative to or in addition to a circular arrangement of multiple light sources. By means of a plurality of light sources arranged in a row, which are switched on and off sequentially or at least partially overlapping in time, it is thus possible to generate a light spot that moves linearly, preferably in opposite directions, across the retina of the patient performing a self-diagnosis.

[0022] A further particular embodiment of the invention provides that the lighting unit comprises a plurality of light sources, in particular LEDs, arranged in the form of a matrix, i.e., in rows and columns preferably aligned perpendicular to one another. Such a matrix is ​​particularly preferably square, so that the same number of light sources is arranged in the respective perpendicularly aligned rows of light sources.

[0023] According to a specific development of the invention, it is further provided that the light sources are at least partially switched on and off one after the other. In addition, it is conceivable that the individual light sources are at least partially switched on and off again in a temporally overlapping manner, with different forms of control being possible. The individual light sources could be switched on and off in a fixed or random order by means of a suitable control system, with it again being conceivable that at least two of the light sources, in particular adjacent light sources, light up simultaneously at least temporarily. By arranging a plurality of light sources in the form of a matrix, a light spot can advantageously be generated on the retina of a patient by directing light onto the patient's retina via different beam paths.Here, as with a different arrangement of the light sources, the device according to the invention is designed such that a patient can carry out a comparatively simple self-diagnosis by simply placing the device against the face in the area in front of the eye. Since the patient can advantageously compare the images they perceive with provided reference images, they can make an assessment of the condition of the retina even without the presence of a treating professional, in particular a doctor. On the basis of this assessment, the patient can then contact or consult a doctor at an early stage for a more detailed diagnosis. This means that, particularly in areas with a low density of doctors, comprehensive support for medical pre- and post-operative care measures can be provided to a certain degree of accuracy.

[0024] In a particular development of the invention, an operating element is provided, for example in the form of a push-button, slide-button, or rotary switch element, the operation of which can activate a control for changing the order in which the light sources are switched on and off, the wavelength and / or intensity of the emitted light, and / or the frequency at which the light sources are switched on and off. According to this embodiment, the device according to the invention thus has both an operating element and a control unit, which enables targeted influencing of the function of the individual light sources of the lighting unit.In this way, it is possible to specifically and needs-based influence the switching on and off times of the individual light sources, the wavelength and / or the intensity of the emitted light and / or the frequency with which light emanates from different light sources, and thus the properties and type of movement of a light spot guided across the patient's retina. If the operating element, the control unit and at least some of the light sources are configured to change the intensity and / or the wavelength, i.e. in particular the color of the emitted light, it is possible for a patient to adjust the brightness and color of the light spot moved across the retina in such a way that the light spot is not perceived as unpleasant and comparatively strong entoptic perceptions are triggered in a particularly advantageous manner.It has been shown that light with an increased green component, i.e. with wavelengths in a range of about 500 nm, is perceived by a patient as particularly pleasant during self-diagnosis and at the same time triggers the required entoptic perceptions.

[0025] Furthermore, the invention also relates to a system for performing a self-diagnosis to determine the functional status of the vascular structure of a retina. The system also makes it possible to detect retinal diseases and / or monitor the progression of the disease within the framework of a self-diagnosis.

[0026] The system according to the invention comprises a device according to at least one of the previously described embodiments, a data processing unit configured to provide retina-, device- and / or disease-specific information, and an output unit by means of which the provided information can be output to an operator, in particular the patient, who carries out a self-diagnosis at intervals.

[0027] It is particularly advantageous if the data processing unit has at least one data storage unit and / or a data interface configured to exchange data containing the required or desired information unidirectionally or bidirectionally with an external data storage device. In this case, it is initially conceivable that the desired information can be made available to the patient quickly and reliably before, during, or after the procedure, especially without the need to consult a doctor.

[0028] According to a specific development of the invention, data containing information about the properties of a retina, device- or device-specific information, such as operating instructions and / or information about the vascular structures of certain retinal diseases, is alternatively or additionally stored in the internal or external data storage device. It is also conceivable for a user, in particular a patient who is performing or has performed a self-diagnosis, to store data on the internal or external data storage device. In this way, observations made by the patient can be advantageously documented, or even a type of diary can be created containing the results of the self-diagnosis performed.

[0029] It is particularly advantageous if the data processing unit described above, in at least one of its embodiments, is part of a tablet computer, a mobile phone, and / or a smartphone. Alternatively, it is conceivable that the data processing unit is at least partially integrated into a device for self-diagnosis of the functional status of the retina according to an embodiment as described above and is connectable to a tablet computer, a mobile phone, and / or a smartphone for further data communication via at least one suitable interface. In this context, it is conceivable in a particularly advantageous manner that a device designed according to the invention for initiating entoptic perception of retinal vascular structures is used in a system together with a tablet computer or a smartphone on which a special application (app) is implemented.

[0030] A suitably designed app implemented on a tablet computer or a smartphone is preferably configured such that, upon a corresponding request, at least one piece of information about the properties, operating status, and / or operating options of the device according to the invention can be output to a patient before, after, or during self-diagnosis via an output unit of the tablet computer or smartphone, in particular via a loudspeaker or a display. In this context, it is conceivable that, in this way, information about the appropriate use or operation, maintenance, and / or servicing of the device according to the invention can be output in a targeted and needs-based manner upon request.It is also conceivable that, by using the application implemented in the data processing system, retinal vascular structures can be displayed on a screen, providing a patient with more detailed information about both healthy vascular structures and possible clinical pictures. Particularly preferably, the application is designed and implemented on a tablet computer or a smartphone in such a way that it provides a patient who is performing or intends to perform a self-diagnosis using a device according to the invention, which is preferably designed as a handheld device, with information about operating steps, potentially perceptible retinal vascular structures, and / or specific clinical pictures.

[0031] According to a particularly suitable embodiment, certain vascular structures, the data for which are stored in an internal or external data memory, are shown graphically on a display to the user, wherein the patient also preferably has the option of showing or hiding structural elements and / or certain parts of the vascular structures initially shown. It is also conceivable, for example when perceiving an aneurysm in the region of the retina, for the patient to place a mark at a corresponding point in the vascular structure shown on a display, which represents the aneurysm perceived by the patient on the retina. In a special development of the invention, the vascular structures orwhich in turn stores the underlying data in an internal or external data storage, whereby the stored data records are preferably provided with a time stamp.

[0032] In this way, it is possible not only to perform a comparatively simple self-diagnosis, but also to document the progression of a disease. The invention thus also relates to a data processing unit for a system according to one of the previously described embodiments, having an implemented computer program product, in particular a special application (app), which is configured to request, as a function of a request signal, from a plurality of data sets, specific data containing retina-, device-, and / or disease-specific information, and to effect the transmission of the data to an output unit and the output of the requested information via the output unit, in particular a display.Furthermore, the implemented computer program product is designed and implemented on the data processing unit in such a way that the patient can store data modified and / or generated by him in a retrievable manner on an internal data storage device of the data processing unit or on an external data storage device.

[0033] A further specific embodiment of the invention provides that a system according to at least one of the previously described embodiments, in particular the data processing unit or a tablet computer, a mobile phone, or a smartphone with a data processing unit further developed according to the invention, has at least one interface that enables unidirectional or bidirectional data communication with an external data processing unit. The system according to the invention further developed in this way is advantageously configured such that it can exchange data with a telemedicine system and / or be integrated into a telemedicine system.In this way, information about the patient, the patient's state of health, any self-diagnoses performed and / or results can be made available directly to a telemedicine system, with the information preferably being accessible only to an authorized physician. Above all, vascular structures perceived entopically by the patient can be transmitted to an ophthalmologist, who can then send suitable information to the data processing unit used by the patient and thus to the patient. It is therefore comparatively easy and quick to transmit information about the functional status of the vascular structures of a retina, in particular any changes that have occurred, to a treating ophthalmologist and to receive instructions from the ophthalmologist and / or initiate further steps just as quickly.All this is possible without the patient having to visit an ophthalmologist. Thus, the invention not only ensures regular and early diagnosis but also enables reliable monitoring of the retinal function even without the ophthalmologist present, making it suitable for use in areas with a low density of ophthalmologists, as is sometimes the case in developing and emerging countries.

[0034] The invention will be explained in more detail below, without limiting the general inventive concept, using specific embodiments with reference to the figures. Identical elements are identified by the same reference numerals. They show:

[0035] Fig. 1 : Schematic representation of the light spot stimulation known from the prior art for initiating entoptic perception in the left and right human eye;

[0036] Fig. 2: Device designed according to the invention for initiating an entoptic perception of the vascular structures of a retina;

[0037] Fig. 3: System consisting of a device according to the invention and a suitably designed data processing unit and Fig. 4: Schematic representation of the entoptic self-diagnosis using a system according to the invention.

[0038] Fig. 5: Sketch of a Purkinje vein figure (Purkinje tree structure) with macular achrin

[0039] Fig. 1 schematically shows a light spot stimulation for initiating entoptic perception in the left and right human eye 7 of a patient, as is known from the prior art. For the stimulation, a light spot is generated using a flashlight, moving either linearly back and forth or circularly over the open or closed eye 7, so that the corresponding light phenomenon on the retina 2 is perceived by the patient. According to the embodiment shown in Fig. 1a), the flashlight moves up and down at a preferred frequency of approximately 5 Hz.

[0040] In Fig. 1b) an alternative embodiment is shown in which the pen lamp is moved by the practitioner in a circular movement over the eye 7, so that the light spot moves in a circular movement over the retina 2 of the patient.

[0041] Using the method described above, the practitioner can trigger the entoptic perception of the Purkinje vein pattern and macular achrin in the patient. This method is primarily used for the early detection and monitoring of diabetic retinopathy, as well as for assessing postoperative visual acuity in cases of media opacities. However, the problem with this method is that the entoptic perception of the retinal vessels 20 depends heavily on the interaction between physician and patient, and the patient has only limited or no control over the quality of the appearance. In particular, it is not possible to generate a stabilized image on which the patient can focus to describe their retinal vessels 20. As explained below, the invention solves this problem and, in particular, enables the patient to perform a reliable and rapid self-diagnosis without the need for an ophthalmologist.

[0042] Fig. 2 shows a device 1 according to the invention for non-invasive direct observation of the retinal vessels 20, in particular the Purkinje vein pattern and the macular ochre, through entoptic perception. The device 1 shown has a housing 4, a handle 3, and a lighting unit 5 arranged inside the housing 4. A contact surface 6 is arranged in the front area of ​​the housing 4, which circumferentially surrounds the lighting unit 5 and can be placed on the head 8 of a patient such that the contact surface 6 surrounds the eye 7 to be examined. The contact pressure and the orientation of the device 1 can be adjusted by the patient as needed.

[0043] According to the embodiment shown in Fig. 2, the lighting unit 5 has a plurality of light sources 9 arranged in a circle and / or in series within the housing 4. When using this device 1, the individual light sources 9 are switched on one after the other and later switched off again, so that light emanating from the various light sources 9 impinges on different points of the retina 2 to be examined at different times.

[0044] In an alternative embodiment of the invention, a servo motor is provided which enables a targeted movement of a light source 9 or a deflecting mirror, so that the emitted light is also transmitted in this way via different beam paths and ultimately strikes different points on the retina 2 of the patient, so that the patient perceives a light spot moving across the retina 2.

[0045] The patient can set different operating modes with regard to the type of switching on and off, the movement of a light source 9 or a deflecting mirror, the intensity of the emitted light, and the light color. If a movable light source 9 or a movable deflecting mirror is used, two operating modes can be set with regard to their movement, so that the light spot is moved either back and forth or at least approximately circularly across the patient's retina 2.

[0046] Using the device 1 shown in Fig. 2 in the form of a handheld device with a lighting unit 5 with a plurality of light sources 9, the patient can trigger the entoptic perception of the Purkinje vein pattern in themselves. Using the device 1 in the operating mode in which a light spot is moved in a circular motion over the retina 2 is advantageous, as experiments have shown that this allows for optimal perception of the retinal vessels 20.

[0047] According to the invention, a device 1, preferably in the form of a small, portable handheld device for initiating entoptic perceptions, is provided by the use of comparatively simple technical means with simultaneous miniaturization. The advantage here is that the patient can place the device with its contact surface 6 onto the eye 7 to be examined and usually carries out self-adjustment completely independently. For the adjustment, the patient intuitively varies in particular the contact pressure and, especially in the case of devices 1 which have several light sources 9 which cannot be moved by a servomotor, the angle of incidence until the vascular structures appear optimal. If this is not successful, the device 1 additionally allows individual adaptation of the light stimulation by varying the light intensity, the light color, the shape of the light beam and / or, depending on the design of the lighting unit, the movement of the light beam.

[0048] With the device 1 shown in Fig. 2, a light beam is generated and emitted so that the light spot impinging on different locations on the retina 2 has a diameter of approximately 0.5 to 3 mm. By using optical lenses as needed or by using movable lenses connected downstream of a light source 9, the focus of the light beam and thus the diameter of the light spot in the plane of the retina 2 can be changed.

[0049] With the aid of the invention, a moving light spot is thus automatically generated on the patient's retina 2, something which was previously only possible if a treating physician manually moved a flashlight over an eye 7 in a suitable manner. In contrast to the methods known from the prior art, the device 1 shown in Fig. 2 allows the light beam to be directed in a standardized, reproducible manner at a defined wavelength and with standardized circular stimulus application through the closed eyelid 7 (transpalpebral) onto the retina 2, as is also shown in Fig. 1 b). This bypasses retinal local adaptation and creates a stable optical perception.

[0050] Fig. 3 shows a schematic representation of a system for suitably carrying out a self-diagnosis of the functional status of the retinal vessels 20, which system comprises, on the one hand, a device 1 designed according to the invention and, in addition, a specially configured data processing unit 12. The data processing unit 12 is capable of storing information about the device 1, such as different operating settings or operating instructions, properties and representations of structures of the retinal vessels 20 and / or information about relevant clinical pictures, and outputting this information upon request by the user via an output unit 13 in the form of a display. Likewise, it is possible for the patient to store the results of their self-diagnosis in an internal data storage unit 14 of the data processing unit 12.An interactive approach is preferred, allowing the patient to compare the vascular structures presented to them with the structures they perceive and to actively show or hide substructures. They can also mark aneurysms they perceive during self-diagnosis. In addition, the patient can keep a kind of diagnostic diary and thus document the results they perceive, thus also allowing for a follow-up review.

[0051] The data processing unit 12 can also be connected to a telemedicine system 18 via a suitable interface 15, enabling an ophthalmologist, for example, to retrieve the information stored by the patient and, based on the findings derived therefrom, to provide the patient with recommendations for action or therapy, in particular for retrieval via the data processing unit 12. In order to implement the functions described above, a computer program product 17 or an application (app) is implemented on the data processing unit 12, which is, for example, part of a smartphone 19 or a tablet computer, which enables the patient to operate the system easily and safely.

[0052] In this context, Fig. 4 additionally shows, in a schematic representation, the implementation of an entoptic self-diagnosis using a system according to the invention. The patient uses the device 1 according to the invention, here in the form of a handheld device, for self-diagnosis of the functional status of his retinal vessels 20. The device 1 is held by the patient himself against the closed eye 7 to be examined. By optimizing the contact pressure and holding angle, the patient corrects the position of the device 1 until a stabilized entoptic perception of the vascular structures is achieved. As required, various stimulation parameters, such as the intensity of the light or the color of the light, can be varied via a control element 10 on the handle 3, the actuation of which causes a control signal to be generated by a control unit 11 or controller.

[0053] For the description and documentation of the subjective appearance of the retinal vessels 20, the user is supported by an assistive computer program product 17, here an application (app) implemented on a smartphone 19. According to the described embodiment, the patient can, for example, view instructions for operating the device 1, typical example images of vascular structures, or training and explanatory videos, and can also document their own results. Furthermore, the computer program product 17 is configured such that the patient can receive training regarding the self-diagnosis they are to perform, which training imparts sufficient expert knowledge and is preferably carried out using animated example images in the form of a map-like representation of retinal vessels 20.Pathologies identified by the patient, such as microaneurysms, can be added or removed with a click in a standardized representation of a typical retinal vascular structure. Thus, the computer program product 17 implemented on the smartphone 19 offers the possibility of documenting the disease progression.

[0054] In addition, an interface 15 for data exchange with a telemedicine system 18 is provided. With the aid of the computer program product 17, the patient's health data can be exchanged with a telemedicine system 19, and even external access by medical personnel or a treating physician to the data stored in a data storage device 14 of the smartphone 19 or an external data storage device 16 can be enabled to clarify the state of health. A major advantage here is that the patient's willingness (adherence) to actively participate in therapeutic measures increases and, if necessary, the number of doctor's visits can be reduced. In this context, it is conceivable for a treating ophthalmologist to routinely check the health status of their patients by retrieving the patient data. During a doctor's visit, the data generated by the patient themselves can then be holistically evaluated together with the current findings.

[0055] The system according to the invention thus enables, in a special way, the documentation, evaluation, and use of results generated during the patient's entoptic self-diagnosis. With the help of the computer program product 17 implemented on a smartphone 19, after the patient has performed the self-diagnosis, a matrix is ​​generated on the display 13 of the smartphone 19, on which the pathological changes perceived by the patient are documented and objectified. The information entered by the patient supports the staging of microangiopathy in diabetic retinopathy, for example, and can help detect progression. By offering this patient cooperation, it is expected that their adherence will be significantly increased and that the treating ophthalmologist will be informed of the progression at an early stage.A tabletop device with interchangeable devices 1 was developed for experiments and initial clinical studies. To stimulate entoptic perception, the devices each have lighting units 5 with multiple light sources 9. To test a suitable arrangement of the light sources 9, the device 1 can be exchanged. Four devices 1 with various at least nearly circular arrangements of multiple light sources 9 and one device 1 with a row arrangement were investigated. The row arrangement of multiple light sources 9 within the housing 4 of the device 1 simulates the effect of a moving light beam, e.g., a flashlight, which is moved back and forth over the patient's eye 7, as shown in Fig. 1 a).

[0056] The tabletop device contains electronics and a programmable microcomputer that enables the wired electrical control of the device 1 used. Control elements on the tabletop device allow the activation and variation of illumination parameters, such as the light intensity, the stimulation pattern, and the stimulation speed, in order to generate a stable shadow image of the retinal vessels 20 for the observer.

[0057] In general, light-emitting diodes with a small beam angle, particularly preferably less than 20°, are preferably used as light sources 9. The light intensity can be adjusted to the needs of a patient performing self-diagnosis, preferably by pulse width modulation. In order to be able to adjust the light color, i.e. the wavelength of the emitted light, devices 1 were used that comprise light units 5 with light sources 9 that emit light of different wavelengths. In addition, light-emitting diodes with white light were tested; however, their characteristic wavelengths dominate in the blue and yellow wavelength ranges. A pleasant entoptic perception was observed by the test subjects predominantly with green-emitting diodes that emit light with a wavelength of approximately 525 nm, which is why this color of the emitted light appears particularly advantageous.The preferred LEDs have a standard plastic LED housing with integrated optical lenses for a focused beam angle of approximately 15°, with the LED housing having a diameter of 3 mm.

[0058] For the devices 1 with circularly arranged light sources 9, a rotating running light with a fading transition (fading effect) of the neighboring light sources 9 was determined in the preliminary test as the preferred stimulation pattern in order to simulate a continuous movement of a point light source 9. The individual light sources 9 were thus switched on and off in such a way that light was emitted from at least two neighboring light sources 9 for at least a certain period of time. The structurally provided individual control 11 of the individual light sources allows this type of commissioning. A preferred direction of rotation, i.e. either counterclockwise or clockwise, was not determined. For the device 1, which has light-emitting diodes arranged in series as light sources 9, a back and forth movement of the light spot is preferably realized.For the evaluation of the test results, the radius of curvature of the eye was assumed to be 15 mm.

[0059] List of reference symbols

[0060] 1 device

[0061] 2 Retina

[0062] 3 Handle

[0063] 4 housings

[0064] 5 lighting units

[0065] 6 contact surface

[0066] 7 Eye

[0067] 8 heads

[0068] 9 Light source

[0069] 10 Control element

[0070] 11 Control

[0071] 12 Data processing unit

[0072] 13 Output unit

[0073] 14 Data storage unit

[0074] 15 Data interface

[0075] 16 external data storage

[0076] 17 Computer program product

[0077] 18 Telemedicine system

[0078] 19 smartphones

[0079] 20 retinal vessels

Claims

Patent claims 1. Device (1) for initiating an entoptic phenomenon of the patient that can be perceived by a patient, with a handle (3) and with a housing (4) in which a lighting unit (5) is arranged, characterized in that the housing (4) has a contact surface (6) that can be placed on the head (8) of the patient in the region of the eye (7) in such a way that light emitted by the lighting unit (5) falls at least partially on the retina (2), wherein the lighting unit (5) is set up to emit light at different times along different beam paths in such a way that the emitted light strikes the retina (2) at different points in time when the contact surface (6) is placed in place.

2. Device according to claim 1, characterized in that the lighting unit (5) has a light source (9) movable by a drive and / or a mirror movable by a drive.

3. Device according to claim 1 or 2, characterized in that the lighting unit (5) has a plurality of light sources (9) which can be switched on and off independently of one another.

4. Device according to claim 3, characterized in that the light sources (9) are arranged in a circular or at least approximately circular manner in the housing (4).

5. Device according to claim 3, characterized in that the light sources (9) are arranged in series in the housing (4).

6. Device according to claim 3, characterized in that the light sources (9) are arranged in the form of a matrix, in particular in rows and columns running perpendicular to one another.

7. Device according to claim 6, characterized in that the light sources (9) are arranged in the form of a rectangular, in particular square matrix. Device according to claim 6 or 7, characterized in that the light sources (9) can be at least partially switched on and off by means of a control such that at least two, preferably adjacently arranged light sources (9) temporarily illuminate together. Device according to one of claims 3 to 8, characterized in that an operating element (10) is provided, the operation of which can activate a control (11) for changing an order in which the light sources (9) are switched on and off and / or a frequency with which the light sources (9) are switched on and off. Device according to one of the preceding claims, characterized in that an operating element (10) is provided, the operation of which can activate a control (11) for changing an intensity and / or a wavelength of the emitted light.A system for detecting a retinal disease, comprising a device (1) according to at least one of the preceding claims, a data processing unit (12) for providing retina-, device-, and / or disease-specific information, and an output unit (13) via which the provided information can be output. The system according to claim 11, characterized in that the data processing unit (12) comprises a data storage unit (14) and / or has a data interface (15) configured to exchange data unidirectionally or bidirectionally with an external data storage device (16). The system according to claim 11 or 12, characterized in that the data processing unit (12) is part of a mobile phone, a smartphone, or a tablet computer.System according to one of claims 11 to 13, characterized in that a computer program product (17) is implemented in the data processing unit (12) which is configured to react thereto. Information can be provided in response to a patient input, data can be stored in an internal data memory of the data processing unit, data can be transmitted to an external data memory, and / or data can be exchanged unidirectionally or bidirectionally with a telemedicine system. A data processing unit (12) for a system according to one of claims 11 to 14, comprising an implemented computer program product (17) configured to select a specific data set from a plurality of data sets containing retinal, device, and / or disease-specific information, depending on a request signal, and to effect transmission to an output unit (13). A computer program product configured to effect interaction between the patient and the system according to one of claims 11 to 14 and / or between the patient and a data processing unit according to claim 15,

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