RU2718269C1 - Stereo vision recovery and development method - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to ophthalmology and is intended for recovery and development of stereovision. Stereoscopic image is displayed alternatively for the right and left eyes with a change in the level of difficulty by varying the level of disparity. Stereo image is a lilac-colored ring located on a black background, inside which there are two identical in shape and size partially overlapping contours of the red and blue butterflies. Image is presented through glasses with a red and blue light filter during 20 tasks. Further, the level of disparity is changed in random order both towards decrease and increase from average level corresponding to 34.25 arcmin. First, alternating regimen is used, including monocular phases for right and left eye and interval with presence of only black background between monocular phases with sequential reduction of duration of monocular phases and interval from 50 to 20 ms. That is followed by a non-alternating regimen in the form of constant presentation of stimuli for the right and left eye, wherein each task is presented with a variable stereoscopic image by changing the distance on the screen between centers of partially overlapping contours of red and blue butterflies with respect to the plane of the ring until the patient's depth is matched by the perceived contour of the butterfly with the ring plane. In the presence of ametropia and an angle of strabismus, a stereotest is presented in conditions of optimal optical correction of ametropia and full prismatic compensation of the angle of eccentricity. Color stimuli have characteristics for red parts – R 255, G 0, B 0, blue – R 0, G 0, B 255, purple – R 215, G 102, B 162.

EFFECT: invention provides improved ability of stereoscopic perception and improved visual acuity.

3 cl, 2 ex, 2 dwg

Description

The present invention relates to ophthalmology and is intended for the restoration and development of stereo vision.

Currently, there is a widespread introduction of 3D technology in various fields of human life and professional activity. In this regard, it becomes more and more urgent to improve the ability to stereo perception not only in patients with gross violations of binocular functions (for example, strabismus), but also in people who do not have serious ophthalmopathology, but who have difficulty assessing depth and / or discomfort with observation of stereo stimuli due to instability of binocular vision, reduced fusional reserves.

Currently, in developing methods for training binocular functions and, in particular, the ability to stereo perception, great importance is attached to creating observation conditions that are as close as possible to the natural, individual selection of parameters of visual stimuli and the mode of presentation (Kashchenko T.P., Raigorodskiy Yu.M. , Kornyushina T.A. Functional treatment for strabismus, amblyopia, and accommodation disorders.Methods and devices.- M.: IIC SSMU, 2016. - 163 p.).

In this regard, the attention of ophthalmologists and orthoptists is increasingly attracted by the use of phase haploscopy in combination with the possibilities of computer presentation of stereoscopic stimuli (Rychkova S., Ninio J. Alternation frequency thresholds for stereopsis as a technique for exploring stereoscopic difficulties // i-Perception, 2011. - Vol. 2. - P 1-17.).

A known method that allows as visual stimuli to use both two-dimensional stimuli and stereo pairs, as well as present images corresponding to the right and left eye alternately or simultaneously. To do this, use two independent electronic displays, separately for the right and left eye, mounted in a special frame of virtual reality glasses. The disadvantage of this method is the mechanical separation of the fields of view, creating observation conditions that are far from natural (US 8328354 B2, 12/11/2010).

A device for treating visual impairment is also known, involving the use of two computer screens located at an angle to each other or one screen with a mechanical separator of the field of view of the right and left eyes and an optics system that allows you to control the accuracy of projection of the right and left images (including stereo stimuli) to the central areas of the retina of the right and left eye. The disadvantage of this method is also the mechanical separation of the visual fields of two eyes and the insufficiently wide choice of the presentation of visual stimuli (EP 1509121 B1, 09/26/2012).

The closest analogue of the proposed method is a method of the same purpose, in which for training stereo vision using a hardware-software complex ZhKOK (liquid crystal glasses - computer). This complex is a combination of glasses with a liquid crystal shutter, a pulse generator and a diskette with a program for a standard IBM-compatible personal computer. The generator delivers impulses to the plates of the glasses in such a way that the right or left eye alternately opens. The switching frequency is 50 Hz, which obviously exceeds the critical fusion frequency of flickers of the human eye. The program recorded on a floppy disk, simultaneously with the switching of the glasses plates, gives the image on the monitor screen alternately for the right and left eye. The patient looks at the monitor screen through the liquid crystal glasses (for patients with ametropia, provided that it is optimally corrected with ordinary glasses or contact lenses). A plot picture appears on the display screen, which the patient with glasses sees in three-dimensional space. The program has 10 difficulty levels with disparity values (created due to horizontal shift of image details visible separately by the right and left eye) from 60 angles. min to 2.5 ang. min The exercises are playful. The patient's task is to correctly assess the relative position of the two test objects and perform the necessary action (for example, by controlling the mouse to knock down the target). The complexity of the task is expressed in a sequential decrease in the degree of disparity of the right and left images, which provides training stereo vision. The result is logged. The disadvantage of this method is the inability to use different modes and durations of presentation of visual stimuli, which limits its correction capabilities (RU 2133103, 07.20.99).

The objective of the invention is to further improve the methods of restoration and development of stereo vision using the presentation of stereo images.

The technical result of the proposed method is to improve the ability to stereo perception and increase visual acuity.

The technical result is achieved by presenting the developed stereotest with color incentives in alternating and non-alternating modes with a change in the level of disparity in a random order both downward and upward from the average level.

In the proposed method, essentially conducting interactive visual training in the conditions of anaglyph separation of visual fields (using red filters for one eye and blue filters for the other eye) by presenting a stereotest in alternating and non-alternating modes. The change in the distance between the stimuli for the right and left eye leads under binocular observation to a change in the perception of the relative distance of the details of the stereo image to improve the ability to stereo perception.

We have developed a test stereo image, which is a purple ring located on a black background, inside of which are located two identical in shape and size partially overlapping contours of the red and blue butterflies - Fig. 1. The color characteristics of stimulus details for red details are mainly characterized as R 255, G O, B 0, blue - R O, G O, B 255, purple - R 215, G 102, B 162. On the monitor screen, for example, 27 × 47.5 cm, the diameter of the ring is, for example, 9 cm, the size of the figure of each butterfly is 3.5 cm vertically and 3 cm horizontally. Dimensions may vary depending on the conditions in which the method is carried out.

When observing this image through glasses with light filters (red filter for the right eye and blue for the left), the purple ring is visible simultaneously with the right and left eye, the red butterfly is visible only with the right eye (through the red filter); blue butterfly - only with the left eye (through the blue light filter). With the successful operation of binocular mechanisms in humans, a stereo effect occurs due to disparity (horizontal distance between the red figure of the butterfly visible by the right eye and the blue figure of the butterfly visible by the left eye). Moreover, in a person with a normal state of binocular functions, the following stereo-effects are possible: 1) if the red butterfly is located on the right and the blue on the left, then the integral (with successful fusion) image of the butterfly is perceived to be located deeper than the ring; 2) if the red butterfly is located on the left, and the blue one on the right, then a holistic (with successful fusion) image of the butterfly is perceived to be located deeper than the ring. In a patient with stereo vision impairment, the stereo effect is absent in the presence of disparity in image details. In this case, only one red butterfly can be visible, only one blue butterfly, or both butterflies can be visible, but as separate (unfusable) figures.

Disparity is created by horizontally shifting the shapes of the red and blue butterflies) when viewing stereo images on a monitor screen.

The proposed visual exercises for the restoration and development of stereo vision are playful in nature. For patients without ametropia and without strabismus, exercises are carried out only with the use of glasses with red and blue filters. For patients with ametropia, in addition to light filters, optimal optical correction of ametropia (glasses or contact lenses) is necessary. If there is a strabismus angle, it is necessary to compensate it additionally with the help of prisms (for example, you can use a set of Luneau prisms, including 22 prism lenses with a power of 1.0 to 50.0 prD). The correctness of the selection of prism correction is controlled using a one-way cover test. For this, a prism with a force approximately equal to the deviation value is placed in front of the examined eye at the moment when the other eye is covered with a shutter. If the strength of the prism is sufficient to compensate for the deviation, there is no adjusting movement of the examined eye. If the installation movement is still observed, repeat the study with a stronger prism, achieving complete disappearance of the installation movements. In FIG. 2. demonstrates prismatic compensation of the strabismus angle and anaglyphic separation of the visual fields in a patient with strabismus: a - eye position under optimal spectacle correction; b - with a prism of 12.0 prD, which compensates for the strabismus angle; c - conditions of anaglyphic separation of the fields of view (a red filter is installed in front of the right eye and blue - in front of the left).

One training exercise involves the patient completing 20 tasks. At the same time, the disparity level is changed in a random order both in the direction of decrease, and in the direction of increase from the average level corresponding to 34.25 angles. min The patient’s task is to evaluate the spatial arrangement of the butterfly butterfly in relation to the plane of the ring (the butterfly is located deeper or deeper than the plane of the ring) and then, using the buttons with the horizontal arrows on the computer keyboard, try to combine the figure of the butterfly in space with the plane of the ring. When the patient has a distinct feeling that the butterfly and the ring are in the same spatial plane, he presses the enter button on the computer keyboard and the program records the result.

In this case, the successful combination of the plane of the butterfly butterfly with the plane of the ring (in this case, on the screen there is an exact coincidence of the figures of both butterflies in the center of the ring) can be indicated as a zero value. If, despite the patient’s feeling that the fusible butterfly is in the same plane as the ring, the figure of the red butterfly is on the left and the blue to the right of the center of the ring, the recorded result is indicated by a positive number, and if the figure of the red butterfly is slightly on the right and the blue on the left the center of the ring, a fixed result is indicated by a negative number.

After completing one task, the patient proceeds to the next one by pressing the up arrow button on the computer keyboard. In this case, the initial disparity and the relative position of the figures of the red and blue butterflies change with the transition to the patient's next task.

Two modes of presentation of visual stimuli are used - non-alternating and alternating. Begin exercise using the alternating mode. It provides for the alternation of visual stimuli in the following order: from the monocular phase for one eye (the ring and the butterfly are visible through the appropriate filter), the interval with the presence of only a black background, the monocular phase for the other eye (the ring and the butterfly are visible through the corresponding filter), the phases with only black background, monocular phase for the other eye, etc. A sequential decrease in the duration of the monocular phases and the interval from 50 to 20 ms is carried out. After achieving successful completion of tasks in the alternating mode, they proceed to perform the same exercises in the non-alternating mode, which provides for a constant (non-alternating) presence on the monitor screen of stimuli for the right and left eye.

At the end of the lesson, after completing all 20 tasks, the overall result of the success of the execution is reflected in the number of successfully completed tasks (for example, 15 tasks out of 20 (15/20) or 18 out of 20 (18/20) have been successfully completed) .

In the method, the duration of the course of treatment and procedures generally accepted in orthoptic treatment was used.

The method is as follows.

Example 1

Patient K.I., age 11 years.

Diagnosis: Common intermittent partially accommodative converging monolateral strabismus of the left eye. Hypermetropia of an average degree of both eyes. Amblyopia dysbinocular weak degree of the left eye.

Visual acuity: vis OD = 0.5 sph (+) 3.5D = 0.9; vis OS = 0.1 sph (+) 4.0 D = 0.5. Refraction under cycloplegia (midriacyl 1% three times): OD = sph (+) 4.0D; OS = sph (+) 4,5D. Hirschberg's squint angle in points from 0 ° to (+) 5 ° OS, without points from (+) 5 ° to (+) 10 ° OS. In conditions of optimal spectacle correction, the squint angle is compensated by a prism 10.0 prD OS ax 180 °, the base to the temple. In a study with a four-point color test, the nature of vision is unstable binocular. When researching with the Lang test and Fly test, stereo vision is absent.

At the first stage of orthoptic treatment, presentation of a stereotest with a color characteristic for red details — R 255, G O, BO, blue — R O, GO, B 255, purple-R 215, G 102, B 162 was used.

in alternating mode. In the first lesson, the duration of the monocular phases and the interval with the presence of only a black background was 50 ms, in the second lesson - 40 ms, in the third 30 ms and in the fourth 20 ms. In the sixth lesson, the exercises were repeated with the duration of the monocular phases and the interval with the presence of only a black background of 20 ms to consolidate the achieved results in the form of successful completion of the majority (18 of 20) tasks.

In the seventh lesson, we proceeded to performing exercises in a non-altering mode of the program. At the end of the lesson, 15 out of 20 tasks were successfully completed. At the eighth, ninth and tenth lessons, the exercises were repeated in a non-altering mode. At the same time, there was a positive trend in the success of the exercises. By the end of the tenth session, all 20 tasks were successfully completed.

At the end of the course (which included 10 lessons of 20 minutes per day): Visual acuity: vis OD = 0.5 sph (+) 3.5D = 1.0; vis OS = 0.2 sph (+) 4.0 D = 0.7. Hirschberg strabismus angle in points 0 °, without points to (+) 5 ° OS. In a study with a four-point color test, the nature of vision is stable binocular. The Lang test is positive (1200-600 arcsec), the Fly test is positive.

Thus, as a result of the course of visual training, there was a positive dynamics in the form of an increase in visual acuity of the left eye, a decrease in the angle of strabismus and its transition from partially accommodative to accommodative, an increase in the stability of the binocular nature of the four-point color test and the appearance of stereo vision in the study with classical stereo tests .

Example 2

Patient W.A., age 10 years.

Diagnosis: Friendly convergent operated strabismus. Weak hypermetropia in both eyes.

Visual acuity: vis OD = 0.7 sph (+) 1.5D = 1.0; vis OS = 0.8 sph (+) 1.0 D = 1.0. Refraction under cycloplegia (midriacyl 1% three times): OD = sph (+) 2.0D; OS = sph (+) 1,5D.

The strabismus angle according to Hirschberg with glasses and without glasses 0 °, prism compensation is not needed. In a study with a four-point color test, the nature of vision is binocular. Lang test is negative, Fly test is negative.

At the first stage of exercises, we used a program for training stereo vision in an alternating mode. A stereo test was presented with a color characteristic for red details - R 255, G 0, B 0, blue - R 0, G 0, B 255, purple-R 215, G 102, B 162.

In the first and second classes, the duration of the monocular phases and the interval with the presence of only a black background was 50 ms, in the second and third classes - 40 ms, in the fourth and fifth - 30 ms, in the sixth and seventh - 20 ms. At the end of the seventh lesson, all tasks were successfully completed. In the eighth lesson, we proceeded to performing exercises in a non-altering mode of the program. At the end of the eighth lesson, 16 out of 20 assignments were successfully completed. At the ninth and tenth lessons, the exercises were repeated in a non-altering mode. At the same time, there was a positive dynamics of success and ease of exercise. By the end of the tenth session, all 20 tasks were successfully completed.

At the end of the course (including 10 lessons of 20 minutes per day):

Visual acuity: vis OD = 0.8 sph (+) 1.25D = 1.0; vis OS = 0.9 sph (+) 1.0 D = 1.0.

The strabismus angle according to Hirschberg with glasses and without glasses 0 °. the nature of vision is binocular. The Lang test is positive (1200-400 arcsec), the entire Fly test is positive.

As a result of the course of visual training, the patient showed a positive dynamics in the form of the appearance of stereo vision in a study with classical stereotests, as well as an increase in uncorrected visual acuity.

Thus, the proposed method for the restoration and development of stereo vision allows not only to improve the ability to stereo perception, but also to increase visual acuity, and in some cases reduce the strabismus angle (if any).

Claims (3)

1. The method of restoration and development of stereo vision by presenting stereo images on the monitor screen alternately for the right and left eye with a change in difficulty level due to a change in the level of disparity, characterized in that the stereo image is a purple ring located on a black background, inside of which there are two identical the shape and size of the partially overlapping contours of the red and blue butterflies, while the image is presented through glasses with a red and blue light filter for 20 tasks ny, and the level of disparity is changed in a random order, both in the direction of decrease, and in the direction of increase from the average level corresponding to 34.25 angles. min, in this case, first an alternating mode is used, including monocular phases for the right and left eyes and an interval with the presence of only a black background between the monocular phases with a sequential decrease in the duration of the monocular phases and the interval from 50 to 20 ms, then the non-alternating mode is used in the form of constant presentation of stimuli for the right and left eye, with each task showing a changing stereo image by changing the distance on the screen between the centers of partially overlapping edge contours hydrochloric butterflies and blue with respect to the plane of the ring to the patient by combining the perceived depth contour butterfly with the plane of the ring. 2. The method according to p. 1, characterized in that in the presence of ametropia and strabismus angle stereotest is presented under conditions of optimal optical correction of ametropia and complete prism compensation of strabismus angle. 3. The method according to p. 1, characterized in that the color stimuli have characteristics for red details - R 255, G 0, B 0, blue - R 0, G 0, B 255, purple - R 215, G 102, B 162 .

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