JP5068770B2 - Process and apparatus for treating blind areas of vision - Google Patents

Description

  The present invention relates to the treatment of blind areas of the human visual field.

  As used herein, “visual system damage” is defined as a disorder of any tissue (or all tissues) related to the processing of vision. Such tissues include, but are not limited to, nervous system tissue from the retina level, including from the retina to the optic nerve and all brain tissue (related to visual processing). Such damage can cause visual impairment or even loss of visual function, resulting in partial or near complete blindness. This damage can arise from a number of causes, and such damage can include retinal damage or visual cortex damage (particularly the primary visual cortex (V1)). Visual system damage can occur for a number of reasons including trauma, stroke, tumor growth or inflammatory disease. The retina can be damaged by retinal detachment, laser damage, or other causes (such as glaucoma or age-related macular degeneration). Retinal damage is referred to herein as “retinal disease”.

  In perimetry (static or dynamic), the subject's visual field function is systematically measured and this method is used to determine the portion of the visual field that is normal, diminished, or lost (blind). Used to identify.

  Treatment of areas of reduced visual or residual visual function or partial visual system damage (“transition zones”) is taught in US Pat. 10 / 503,869 (Patent Document 2).

  However, the “blind zone” has not been thought to be ameliorated by therapeutic treatment. The reason is that once the visual cortex is damaged, it has been assumed that visual recovery is impossible. However, in recent years, several authors have described neuronal pathways in the brain that often bypass the damaged cortex and are therefore often unaffected by damage. These are commonly referred to as “extrastriatal” pathways, which allow information to travel from the retina to a higher processing center in the brain and thus bypass the primary visual cortex or other damaged areas. it can.

  In the normal brain, these pathways are thought to be related to the perception of moving visual stimuli, so that even if the primary visual cortex is damaged, they move without the patient being fully aware of the visual stimuli. The ability to recognize (or correctly guess) the stimulus continues to be maintained. This phenomenon is known as “blind vision”.

It is a well-understood problem that patients whose primary visual pathway is damaged cannot recognize visual stimuli and thus have a completely blind or partially blind site. While current stimulation treatment paradigms can help regain some of the lost vision, this prior art approach stimulates the residual visual site (ARV) of the damaged primary pathway itself In that case, some residual vision can be found at the start of treatment. However, the improvement achieved by stimulating the surviving cells in the primary system is very labor intensive, but cannot achieve full recovery. Therefore, a method that can achieve faster or more complete recovery is desirable.
US Pat. No. 6,464,356 US Patent Application Publication No. 2005/0213033

(Summary of the Invention)
Embodiments of the present invention can speed up visual recovery and can provide a greater degree of recovery than previously achieved visual recovery. In some embodiments, a stimulation paradigm can be implemented that utilizes a secondary residual visual pathway that continues to provide information to the blind zone. This approach can provide greater stimulation to the higher sites in the brain (above the primary visual cortex) and thus promote overall recovery of vision. The stimulus may be a moving stimulus. The moving stimulus may be in the form of a simple or more complex geometry or object.

  In a first embodiment of the present invention, a method for treating the human visual system is provided. There is at least one blind zone in the patient's field of view. The method of this embodiment can include applying a stimulation pattern to a human such that the stimulation pattern is applied to at least a portion of at least one blind zone, and recording a human response based on the stimulation. The method of this embodiment can also include providing additional stimulation patterns based on the response. In one embodiment, the stimulation pattern is applied to the entire blind zone. In another embodiment, the majority of stimulation is given to the blind zone.

  Other embodiments of the present invention include an apparatus or system that performs the steps described above. In one embodiment of the present invention, an apparatus for treating a human visual defect is provided. The device includes a light emitting module having a plurality of separately actuable locations, each location adapted to emit a light stimulus to target a different part of the human visual field. The apparatus also includes a processor module that repeatedly selects and activates an operational location based on a human input visual field map. The processor selects the majority of the operable locations to target the blind area of the field of view.

  In related embodiments, the device can include an input module for capturing a human response to a light stimulus. The processor can use these responses to selectively target blind regions. The processor may also select and actuate one or more fixation stimuli. The fixation stimulus can include a plurality of fixation anchor locations surrounding a central blind zone.

  In other embodiments of the invention, methods are used to treat the human visual system, including the retina, visual cortex, and / or other neuronal structures. Locate and define the reduced visual blind zone in the human visual system. A treatment area located primarily within the blind zone is defined and visual stimuli are applied to the human visual system. Most of the stimulation is given to at least a portion of the blind zone.

  The steps of locating, defining, and treating the blind zone can be repeated to expand the human intact field of view into a previously defined area defined as a transition of the blind zone. Using a computer, these steps can be performed in an automated or semi-automated manner. This iteration may include directing a stimulus to an area proximate to the border of the blind area.

  Each step of locating and defining the blind zone can be accomplished using peripheral vision measurements. These steps can also be accomplished by automatically stimulating multiple target areas of the field of view and recording the human response to the stimulus.

  The stimulus used may be a static stimulus or a dynamic (moving) stimulus. Stimulation can come from a head mounted display. A head-mounted display can provide an initial series of stimuli to the first human eye and another series of stimuli to another human eye. If the blind zone is associated with the first eye, another eye can be treated with a different stimulation regime. The different stimulation regimes can target a transition zone, an intact zone, or no area at all.

  The foregoing features of the invention will be more readily understood by reference to the following detailed description, taken in conjunction with the accompanying drawings, in which:

(Detailed description of specific embodiment)
Definition. The following terms used in this description and the appended claims have the meanings indicated, unless the context requires otherwise.

  As used herein, the term “region of undamaged vision” is not substantially damaged or affected by an event that leads to impairment of the visual system, ie it is subjected to an optical stimulus. It means the region of the visual field (or part of the brain) that shows normal or poorly reduced visual function. In contrast, the term “reduced visual area” (used in a similar way to the term “residual visual function area” or “partial visual system damage area”) refers to an accident, Events such as stroke, degenerative disease, or retinopathy (such as glaucoma or retinitis pigmentosa) cause brain or retinal damage that affects human visual ability, resulting in at least partial loss of vision Or is defined to mean an area where partial or complete blindness is reached.

  The present invention generally relates to a method for treating human vision by applying optical stimuli to such areas. Visual stimulation can be achieved in a more complete or quicker way by stimulating those pathways using specific stimuli targeted to the lesion-free pathway. In an exemplary embodiment, the stimulus is applied to a “blind zone” within the human visual field. As used herein, the term “blind zone” refers to a field of view that would be classified as a blind spot in commonly used visual field testing methods (ie, excluding special methods such as the use of magnetic resonance imaging). Means any area. In general, it is the region of the field of view in which humans cannot consciously respond to stimuli given by peripheral perimetric methods.

  In an embodiment of the invention, treatment is performed by directing optical stimulation energy to primarily target the human blind zone. In a related embodiment, the stimulus is directed only to the human blind zone.

  FIG. 1 shows a normal field of view (VF) defined to have a circular shape. Shown is a target stimulus TS1 being applied to the field of view VF on a monitor having a monitor frame (MF). The target stimulus TSI can be given by a computer monitor, for example. The stimulus may be any type of stimulus, and some or multiple stimuli may be given together or continuously, with or without another type of background. Useful target stimuli are characters, words, sentences, meaningful objects (figures, faces, photographs, etc.) or meaningless objects (dots, line patterns, etc.) that move or do not move on the screen However, it is not limited to these. The stimulus may include one dynamic pattern of shape, form and color. Furthermore, the delivery of the target stimulus may be varied in yet another way. For example, one or more of the color, brightness, strength, shape, or size of the stimulus may be changed when applied to a human.

  The fixation point (F) and target stimulus for fixing the human eye to be treated may be applied in one place. As shown, the fixation point (F) is in the undamaged visual area.

  However, in some embodiments of the present invention, the target stimulus TS1 (and thus also the fixation point F) is provided in or near the blind zone.

  FIG. 2 shows the case where the visual system in one hemisphere is not functioning. This hemisphere is a blind zone (B). In one embodiment, fixation point F is applied to the blind zone, such as the target stimulus “TS1” (ie, a stimulus for treating the blind zone). As shown, and optionally another target stimulus “TS2” can be applied, partly to the intact field and partly to the damaged field (transition zone TZ).

  FIG. 3 shows the case where the central part of the visual system (eg where the fovea is located) is damaged (“donut-shaped field of view”). In such a case, a fixation point cannot be given to the central part (it will not be recognized because it is damaged), but the so-called “fixed anchor” is located around the blind area (where the undamaged visual area is located). , Defined place). A visual stimulus is then applied to the intact visual area, in this case in the form of words. A fixation stimulus may also be located in the center. As an example, the fixation stimulus can be a color change at 200 ms intervals. Color changes can occur at indefinite times so that the patient cannot predict. The patient is instructed to respond to changes in the fixation stimulus by pressing a button, and the button press is recorded by the processor. The fixation stimulus can be, for example, a 9-pixel green stimulus on a liquid crystal display that changes to a yellow stimulus after various time intervals. The fixation stimulus can be tailored to an individual patient, for example, by enlarging it or using shape cues without color for color blind patients. In one embodiment, the location of the blind zone and possibly its size can be identified (step 402), as roughly shown in the flowchart of FIG. In some embodiments, the location and size of the transition zone can be specified. The measurement can be performed by methods known in the prior art. In one embodiment of the present invention, a standard peripheral vision measuring device, that is, a device commonly used in ophthalmic practice can be used.

  In another embodiment, visual field measurements can be made using a computer that quantifies the visual level at various points within the visual field perimeter. Such an apparatus can define blind areas, partially damaged areas, and intact zones of the field of view. In some embodiments, the treatment area can be selected depending on the size and location of the blind zone. In one embodiment, the transition zone can be treated together with the blind zone.

  A stimulation pattern is also selected (step 404). As described above, the stimulus pattern may actually be any stimulus. For example, the stimulus can be sized to stimulate the entire blind field while not stimulating the intact field at the same time. The stimulus may be a moving stimulus (such as a moving helix, lattice or moving form and shape). The stimulation pattern may be applied using a computer screen, a VRT device, a head-mounted display lens or screen (eg, goggles or glasses), or other suitable release device.

  The human response to the stimulus can be recorded, which can indicate a change in the visual system (step 406). That is, the person can indicate that he / she has recognized the stimulus and can receive the indication. For example, a human can press a button to indicate when a stimulus is recognized. In some embodiments, such a stimulus can be detected even when the stimulus is applied to a blind zone. In some cases, the screen or human can be masked so that the stimulus is only applied to the blind zone. Although this masking process can be performed physically, it can also be performed more conveniently using a computer.

  Different parts of the blind zone can be stimulated based on individual human abilities that can be determined continuously or intermittently during or between treatment periods. The type, shape, strength, duration and time series of treatment stimuli are not limited. One type or more types of therapeutic stimuli can be used. In the latter case, several types can be used at the same time or sequentially at different times. In some embodiments of the invention, an optical or light stimulus is provided to the human visual system. In some embodiments, light stimuli of different colors, brightness, intensity and / or shape can be applied to the human visual system being treated. Such light stimuli can be applied as static light stimuli or a series of light stimuli that produce the impression of a moving object. In another embodiment, a simple depiction of a daily life item or a more discriminating form of stimulation can be applied to the undamaged visual area of the human being treated. Such a depiction may be static or moving (dynamic) as desired. However, the present invention is in no way limited to the above-described preferred embodiments relating to the stimulus to be applied.

  FIG. 5 selects a target parameter for light stimulation, drives the luminescent display using that parameter to emit the stimulus, records the patient's response to the stimulus, and uses the patient response for repeated processing. Fig. 2 shows a schematic diagram of an apparatus for automatically selecting new parameters. The patient is placed in a fixed position in front of the display. The computer selects a portion of the display and drives the display to emit light in that portion. The computer also emits a fixation stimulus (eg, a fixed anchor in FIG. 3). The patient uses his input device to enter his response and the computer records that response or no response. After testing various parts of the patient's field of view, the computer uses the information from the test and selects another part to stimulate accordingly. The computer may be adapted to perform any of the treatment processes described herein. The display may be a desktop display such as an LCD or CRT. Processing circuitry may optionally be incorporated into the display. A head positioning device may be used to reproducibly position the patient's head relative to the tabletop display. The display may also be a head-mounted display (eg, goggles or helmets that incorporate a display screen for each eye). When using a head mounted display, various treatment regimes can be given to each eye. For example, if there is blindness in one eye and the other eye is slightly worse, the stimulus is blindness in the larger affected eye and in the smaller affected eye Can be given to the transition part.

  FIG. 6A represents a moving spiral stimulus. However, when given unchanged, the helix will stimulate an intact field, as shown in FIG. 6B. This stimulus can significantly affect the perception, which can be annoying for the patient. To overcome this problem, the embodiment shown in FIG. 7A can be used. As represented in FIG. 7B, the helix is not completely shown and is only limited to the blind area. In the embodiment of FIGS. 6A-7B, the majority of the blind area is stimulated.

  FIG. 8 shows an outline of the visual system. The left circle shows a spot stimulus that affects the two branches of the visual system (i.e., primary region (V1) and higher secondary cortical portions (V2-V5)). The motion detection path is indicated by “MT”. Stimulation exerts about 90% of its action on V1 and the rest of its action (about 10%) on the secondary area. The secondary visual system existing on V1 is composed of two extrastriatal pathways and two pathways within the extrastriate cortex. The extrastriatal pathway passes over the optic tectum and thalamic pillow that bypass V1, and transmits information directly to the superior extrastriate cortex.

  FIG. 9 shows the effect of lesions on the primary and secondary visual systems. The blind part is represented by a black circle of V1 and a black rectangle of the secondary system. The transition zones are represented as a speckled circle and a rectangle, respectively. If the damage is in V1, the upper cortical parts (V2-V5) will receive less input and may result in atrophy.

  FIG. 10 represents the effect of a standard VRT (ie, Visual Restoration Therapy that does not primarily target the blind zone). The left rectangle represents a dark display with a local luminescent stimulus shown as a white circle. The action of VRT in reducing the blind zone and transition zone is mainly exerted through V1.

  In contrast, FIG. 11 illustrates how embodiments of the present invention (eg, those described with respect to FIGS. 7A-7B) stimulate the tectum and thalamus to stimulate alternative pathways, thereby facilitating visual recovery. Indicates what to do. The left rectangle represents a moving helical stimulus applied mainly to the majority of the blind zone to target the secondary region. In some cases, since V1 is also targeted, a high luminous spot stimulus is given to a specific part of the moving stimulus, whereby both kinds of treatment can be performed, and a synergistic effect can be expected. FIG. 12 shows the potential of such treatments where the size of the blind and transition zones associated with the secondary region has decreased and the upper part is more responsive to stimuli via any of the routes. Effect.

  In some embodiments, an algorithm according to the above presentation strategy can be used. Using such an algorithm, a region or site of visual system function can be treated very efficiently (and in some cases, parallel or continuous treatment of dysfunction or dysfunction is also possible). The detailed steps of the treatment procedure are described below with respect to stimulating specific areas or regions of the human visual system with optical stimuli.

  During the treatment step, changes in the patient's visual system characteristics are recorded. In other words, the patient's ability to visually recognize and respond to optical stimuli is recorded by the system / device of the present invention. In one example, a patient's response time to an optical stimulus applied to an intact zone of the patient's visual system is measured. This response time can be compared with a reference value. The reference value may be a baseline value measured before the start of treatment. However, this example should not be considered as limiting the present invention. Other measurement techniques may be used to record changes in human visual system characteristics continuously or intermittently.

  In one embodiment, the response of a human being treated when given one or more stimuli is measured and rewarded for that human ability. This can be done in such a way that reward points are added to the “reward account” when the response meets predetermined criteria. For example, when the person being treated is instructed to do as fast as possible, reward points are added to the reward account only if the response is recorded within a predetermined time delay (response time). Alternatively, reward points may be awarded to a reward account when the discrimination is done correctly (eg, correct shape, correct color, time discrimination).

  Based on the measurement and recording of the characteristic changes described above, the location and definition of the blind zone may be redefined. In other words, a blind zone is newly defined depending on the patient's ability to process a given optical stimulus in the visual system. This redefinition process may be performed continuously or intermittently. In one embodiment of the present invention, the reward points are used to determine when to automatically make the next task difficult. Although not wishing to be bound by explanation, the vision of the human being treated can be assumed that the blind zone can be improved because the defined blind zone is effectively treated. Functional improvements including, for example, peripheral vision, visual acuity, discrimination ability (between different colors, shapes, movements), reduced strabismus, increased viewing angle, improved visual function in general or removed partial visual system damage Can happen to some extent. As a result, the area of undamaged vision is expanded (and the blind zone is reduced) or at least its contribution to human vision is improved. As can be seen, the patient experienced a subjective improvement in overall vision in relation to improved performance in treatment. By repeating the above steps, the human intact field of view can be extended to an area previously identified and defined as a transition zone.

  The treatment can be carried out with a medical device using a computer for use in a home that is regularly practiced by the person being treated. In one embodiment, a one hour daily treatment in a darkened room can be performed over an extended period of time, such as, for example, the six months used in this study. However, it will be appreciated that other treatment periods are also effective.

  In one algorithm, a light stimulus is emitted on the display device that results in repeated visual stimulation of the blind zone. In the first step, a “blind zone” is located, defined and characterized. That is, accurate visual function measurements in the intact visual area are made with respect to location, size, and type. A treatment area located within the blind zone is then defined. The treatment area is the portion within the blind zone where recovery of neuronal tissue in the human visual system can be expected due to the result of defining and characterizing the blind zone in the first step.

  In subsequent steps, the blind zone is stimulated in a manner based on the capabilities determined in the first and second steps. Typically, when stimulating the blind zone, the intact zone is given little or no stimulation. Also, unlike prior art devices where the program only saves the data for later analysis, embodiments of the present invention can be used continuously or intermittently in the blind system in or near the blind zone. Includes computer programs that adapt treatment algorithms to their capabilities. The computer program can be operated automatically (ie, without human intervention) to adjust the stimulation pattern to match. The program can be associated with the device locally, so there is no need to transmit data to a remote location (eg, via the Internet). This fitting process measures each response from the patient, collects a summary of responses, or measures to a certain statistically significant level (eg, peripheral visual field measurements or visual field measurements). Can be executed after reaching. The program can also operate in a semi-automated manner. For example, a period of time can be automatically adapted and data transmitted to caregivers from time to time or periodically for review.

  In addition, the results of daily treatment can be stored on a suitable storage medium such as tape or disk, so that it can be monitored for compliance and the treatment policy in the human course. Can be adapted. The results of these daily treatments can also be communicated over the Internet (in real time or late).

  In another embodiment, the disclosed visual treatment method can be implemented as a computer program product for use with a computer system, including a medical device using a computer using an appropriate algorithm. Such means may be fixed to tangible media such as computer readable media (eg, diskette, CD-ROM, ROM, or fixed disk), or a modem or other interface device (local area network (LAN)). Or a series of computer instructions that can be transmitted to a computer system via a communication adapter connected via media to a network including a wide area network (WAN). The media may be either tangible media (eg, optical or analog communication lines) or media implemented with wireless techniques (eg, microwave, infrared, or other transmission techniques). The series of computer instructions embodies all or part of the functionality previously described herein with respect to the system. Those skilled in the art will appreciate that such computer instructions can be written in a number of programming languages for use with many computer architectures or operating systems.

  Further, such instructions can be stored in any storage element, such as a semiconductor storage element, a magnetic storage element, an optical storage element or other storage element, and further, an optical transmission technique, an infrared transmission technique, a microwave transmission technique. Or any other communication technology such as other transmission technologies. Such computer program products are distributed as removable media (eg, software packages) with printed or electronic documents attached, or preloaded with the computer system (eg, in the system's ROM or fixed disk). Or could be distributed from a server or bulletin board over a network (eg, the Internet or the World Wide Web). Of course, some embodiments of the invention may be implemented as a combination of both software (eg, a computer program product) and hardware. Still other embodiments of the invention may be implemented as all hardware, or all software (eg, a computer program product).

  While various exemplary embodiments of the invention have been disclosed in the foregoing description, those skilled in the art will make various modifications that achieve some of the advantages of the invention without departing from the true scope of the invention. It should be clear that it can be done.

Represents normal vision. Represents a field of view where one hemisphere is not functioning. It represents the visual field where the central part of the visual field is damaged. 1 shows an example of a method for treating a blind zone. 1 shows a schematic diagram of an apparatus in an embodiment of the present invention. FIG. 6A shows a spiral stimulus. FIG. 6B shows a map of the spiral stimulus of FIG. 6A when the spiral stimulus affects the patient's field of view. FIG. 7A shows a masked spiral stimulus. FIG. 7B shows how the masked spiral stimulus of FIG. 7B affects the patient's field of view. A schematic diagram of the visual system is shown. A representation of a visual system with a lesion is shown. 10 shows how the visual system of FIG. 10 can be stimulated with a conventional VRT. FIG. 11 illustrates how the visual system of FIG. 10 can be stimulated by embodiments of the present invention. FIG. 13 illustrates how the visual system of FIG. 12 may be improved as a result of embodiments of the present invention.

Claims (14)

A system for treating the human visual system, including the retina, visual cortex and / or other neural cell structures,
(A) means for locating and defining a blind zone in the human visual field , the blind zone being on a region of the retina that is currently blind ;
(B) means for defining a treatment region located primarily in the blind zone;
(C) a visual stimulus and means for presenting to the treatment area, the system.   The system of claim 1, wherein the means for locating and defining the blind zone is a perimetry.   The system of claim 1, wherein the system comprises a computer used to perform the treatment in an automated or semi-automated manner.   The means for locating and defining the blind zone uses automatic presentation of stimuli to a plurality of target regions of the field of view and records the human response to the stimuli. System.   The system of claim 1, wherein the visual stimulus is one of a static stimulus and a moving stimulus.   A head mount configured to provide the visual stimulus to the first series of stimuli to the first human eye and the second series of stimuli to the second human eye. The system of claim 1, wherein the system is a display.   The blind zone is associated with the first eye, and the second eye is suitable for being treated with a different stimulation regimen that treats the transition zone, the intact zone, or no zone at all The system according to claim 6. A device for treating a human visual defect,
A light emitting module having a plurality of separately operable locations, each location adapted to emit a light stimulus so as to target a different part of the human visual field;
A processor module adapted to repeatedly select and operate an operable location based on the human input visual field map, such that a majority of the operational location targets a blind region of the visual field. A processor module , wherein the blind region is on a region of the human retina that is currently blind .   9. The apparatus of claim 8, further comprising an input module for capturing the human response to the light stimulus.   The apparatus of claim 9, wherein the processor uses the response to target the blind region by selecting and actuating one or more fixation stimuli.   9. The apparatus of claim 8, wherein the light emitting module presents a stimulus that provides visual perception of movement, the stimulus comprising a dynamic pattern of one of shape, form and color. The apparatus of claim 11, wherein the stimulus is a spiral stimulus.   The apparatus of claim 11, wherein the light emitting module also provides spot stimulation. The light stimulus is released from a head-mounted display configured to present a first series of stimuli to the first eye of the human and a second series of stimuli to the other eye of the human. The apparatus according to claim 8.

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