An eye movement examination device

Abstract

The application discloses an eye movement examination device, which is characterized by comprising a display module, a near-infrared image shooting module, a calibration module, an eye movement point calculation module and a smooth pursuit eye movement examination result judgment module. The application has the beneficial effect that the horizontal smooth pursuit eye movement examination and the vertical smooth pursuit eye movement examination can be performed on the examinee, the eye movement examination data of the two eyes are recorded and compared, the abnormal eye movement data caused by the abnormal reasons such as the blocking of the pupil by eyelashes, the blocking of the pupil by eyelids, the reflection of the eyeglass, the eye diseases and the like of the non-central nervous pathway function is effectively excluded, the smooth pursuit eye movement examination result can more accurately reflect whether the function of the smooth pursuit eye movement central nervous pathway is abnormal, and therefore the accuracy of the depression disorder screening or the auxiliary diagnosis through the smooth pursuit eye movement examination is improved, and the misjudgment rate is reduced. Moreover, the risk level of the examinee suffering from the depression disorder can be evaluated.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically to a device for eye movement examination. Background Technology

[0002] Eye movement, also known as eyeball movement, is the process of using the eyes to follow the movement of a smoothly moving object. Smooth pursuit eyemovement (SPEM), also called smooth tracking eye movement, smooth following eye movement, or steady eye tracking, is generally considered to be the process of the eyes following the movement of a smoothly moving object. Currently, it is generally believed that the main central neural pathways involved in smooth pursuit eyemovement are: the brain (including the frontal lobe oculomotor area, supplementary oculomotor area, and parts of the temporal, parietal, and occipital lobes) receives visual information from both eyes, analyzes and integrates it, and sends nerve impulses. These impulses first descend to the dorsolateral pontine nucleus in the brainstem, then to the flocculus and vermis of the cerebellum, and the medial vestibular nucleus in the brainstem. The cerebellum regulates the speed of smooth pursuit, maintaining synchronous movement between the eyes and the stimulus. The basal ganglia and superior colliculus also play a role in the control of smooth pursuit eyemovement. Finally, eyeball movement is controlled through the oculomotor nucleus, trochlear nucleus, and abducens nucleus in the brainstem.

[0003] Studies have found that patients with depressive disorders often have central nervous system damage in certain brain regions. For example, magnetic resonance imaging (MRI) studies have revealed a higher proportion of abnormalities in the frontal and temporal lobes of patients with depressive disorders. Single-photon emission computed tomography (SPET) shows reduced blood flow and decreased activity in the cerebral cortex of some patients with depressive disorders, particularly in the temporal and frontal lobes. This type of damage may be caused by genetic factors, or it may be caused by trauma or medication.

[0004] Currently, the main methods for diagnosing depressive disorders include psychiatric consultations and self-rating scales. Psychiatric consultations primarily involve an in-person examination by a psychiatrist to inquire about the triggers for the onset of symptoms, current symptoms, duration, and severity. This process is time-consuming, often lasting several tens of minutes, and requires a specific setting such as a hospital clinic, making it inconvenient for rapid screening in schools or communities. Self-rating scales are questionnaires completed by the individual using a computer or paper, and the risk of developing the disorder is assessed through scoring. However, self-rating scales are highly subjective and have low accuracy.

[0005] Using a self-developed eye-tracking examination device, the inventors discovered through clinical eye-tracking examinations that approximately 80% of patients with depressive disorders exhibit abnormal results on smooth tracking eye movements. This may be because the areas of central nervous system damage in depressive disorder patients overlap to some extent with the smooth tracking eye movement pathway. The damage to the central nervous system in depressive disorder patients leads to abnormalities in certain links of the smooth tracking eye movement pathway, thus resulting in abnormal smooth tracking eye movement test results. Therefore, smooth tracking eye movement testing can serve as an effective method for screening or assisting in the diagnosis of depressive disorders.

[0006] The inventors also discovered in clinical eye movement examinations that abnormalities in smooth tracking eye movement data can be caused not only by dysfunction of the central nervous system pathway for smooth tracking eye movement, but also by non-central nervous system pathway dysfunctions such as eyelashes obscuring the pupil, eyelids obscuring the pupil, lens reflection, and eye diseases (such as strabismus and oculomotor palsy). Therefore, if abnormalities in smooth tracking eye movement data caused by non-central nervous system pathway dysfunctions such as eyelashes obscuring the pupil, eyelids obscuring the pupil, lens reflection, and eye diseases can be ruled out, the results of smooth tracking eye movement examination can more accurately reflect whether the central nervous system pathway for smooth tracking eye movement is dysfunctional. This improves the accuracy of screening for or assisting in the diagnosis of depressive disorders using smooth tracking eye movement examination and reduces the misdiagnosis rate.

[0007] The invention patent application CN116115179A, entitled "Eye Tracking Examination Equipment," proposes a method for determining whether the results of smooth tracking eye movement examination are abnormal. Although this method can automatically calculate statistical data such as average tracking deviation, total number of rapid eye movements, and total amplitude of rapid eye movements from eye movement point data, and automatically determine whether the results of smooth tracking eye movement examination are abnormal based on these statistical data, it cannot distinguish whether the abnormal results are caused by abnormality in the central nervous pathway of smooth tracking eye movement, or by non-central nervous pathway dysfunction such as eyelashes obscuring the pupil, eyelids obscuring the pupil, lens reflection, or eye diseases. Summary of the Invention

[0008] The purpose of this invention is to provide a device for eye movement examination and statistical analysis of the results data, and to exclude eye movement data abnormalities caused by reasons other than central nervous system pathway dysfunction, so that the eye movement examination results can more accurately reflect whether the function of the smooth eye movement central nervous pathway is abnormal.

[0009] To achieve the above objectives, the technical solution of the present invention is to provide an eye movement examination device, characterized in that it comprises:

[0010] The display module can display two modes, defined as Mode 1 and Mode 2. Mode 1 is for horizontal smooth eye-tracking testing, where the display module shows a target that moves smoothly in the horizontal direction. The trajectory of the target's movement is controlled by the program, and the position of the target at each moment is known. Mode 2 is for vertical smooth eye-tracking testing, where the display module shows a target that moves smoothly in the vertical direction. The trajectory of the target's movement is controlled by the program, and the position of the target at each moment is known. When the target moves, the subject's eyes follow the movement of the target. In both horizontal and vertical smooth eye-tracking tests, the left and right eyes can see the target simultaneously.

[0011] The near-infrared image capturing module includes at least one near-infrared camera and at least one near-infrared light source, and is capable of capturing images of the left eye and the right eye simultaneously.

[0012] The calibration module is used to calibrate the left and right eyes, obtaining the left eye calibration function through the left eye calibration and the right eye calibration function through the right eye calibration.

[0013] The eye-tracking point calculation module calculates the coordinates of the left eye-tracking point based on the left eye image and the left eye calibration function after the left eye calibration and the right eye calibration function.

[0014] The smooth eye-tracking test result judgment module is used to record the coordinate data of the left and right eye movement points and then determine whether the subject's smooth eye-tracking test results are normal or abnormal: In the horizontal smooth eye-tracking test, the recorded coordinate data of the left eye movement point is the left eye horizontal smooth eye-tracking test data, and the recorded coordinate data of the right eye movement point is the right eye horizontal smooth eye-tracking test data; in the vertical smooth eye-tracking test, the recorded coordinate data of the left eye movement point is the left eye vertical smooth eye-tracking test data, and the recorded coordinate data of the right eye movement point is the right eye vertical smooth eye-tracking test data.

[0015] If the subject's horizontal smooth tracking eye movement test data is abnormal in both the left and right eyes and the eye movement trajectories are consistent, then the subject's horizontal smooth tracking eye movement test result is considered abnormal; if the subject's horizontal smooth tracking eye movement test data is normal in both the left and right eyes and / or the right eye movement test data is normal, then the subject's horizontal smooth tracking eye movement test result is considered normal.

[0016] If the subject's left eye vertical smooth following eye movement test data is abnormal and the right eye vertical smooth following eye movement test data is abnormal, and the eye movement trajectories of both eyes are consistent, then the subject's vertical smooth following eye movement test result is judged to be abnormal; if the left eye vertical smooth following eye movement test data is normal and / or the right eye vertical smooth following eye movement test data is normal, then the subject's vertical smooth following eye movement test result is judged to be normal.

[0017] If the subject's horizontal smooth eye-tracking test result is abnormal or the subject's vertical smooth eye-tracking test result is abnormal, then the subject's smooth eye-tracking test result is judged to be abnormal; if the subject's horizontal smooth eye-tracking test result is normal and the subject's vertical smooth eye-tracking test result is normal, then the subject's smooth eye-tracking test result is judged to be normal.

[0018] Preferably, in the smooth eye movement tracking test result judgment module, judgment thresholds PZ1, PC1, and PF1 are set for horizontal smooth eye movement tracking test; and judgment thresholds PZ2, PC2, and PF2 are set for vertical smooth eye movement tracking test.

[0019] The method for determining whether the left eye's horizontal smoothed eye movement tracking data is normal or abnormal is as follows: The smoothed eye movement tracking result judgment module calculates the average tracking deviation Z of the left eye during the horizontal smoothed eye movement tracking test. hl Total number of rapid eye movements (REMs) in the left eye (C) hl Total amplitude of rapid eye movement (REM) of the left eye F hl When Z hl >PZ1, or C hl >PC1, or F hl When Z > PF1, it is judged as abnormal in the horizontal smooth tracking eye movement test data of the left eye; when Z hl ≤PZ1, and C hl ≤PC1, and F hl When ≤PF1, the data of the left eye horizontal smooth eye movement test is judged to be normal;

[0020] The method for determining whether the right eye horizontal smoothed eye movement test data is normal or abnormal is as follows: The smoothed eye movement test result judgment module calculates the average tracking deviation Z of the right eye during the horizontal smoothed eye movement test. hr Total number of rapid eye movements (REMs) in the right eye (C) hr The total amplitude of rapid eye movement (REM) of the right eye F hr When Z hr >PZ1, or C hr >PC1, or F hr When Z > PF1, it is judged as abnormal in the horizontal smooth tracking eye movement test data of the right eye; hr ≤PZ1, and C hr ≤PC1, and F hrWhen ≤PF1, the data of the right eye horizontal smooth eye movement tracking test is considered normal;

[0021] The method for determining whether the left eye's vertical smooth tracking eye movement test data is normal or abnormal is as follows: The smooth tracking eye movement test result judgment module calculates the average tracking deviation Z of the left eye during the vertical smooth tracking eye movement test. vl Total number of rapid eye movements (REMs) in the left eye (C) vl Total amplitude of rapid eye movement (REM) of the left eye F vl When Z vl >PZ2, or C vl >PC2, or F vl When Z > PF2, it is judged as abnormal in the left eye vertical smooth tracking eye movement test data; when Z vl ≤PZ2, and C vl ≤PC2, and F vl When ≤PF2, the data for the left eye's vertical smooth tracking eye movement test is considered normal;

[0022] The method for determining whether the right eye's vertical smooth tracking eye movement test data is normal or abnormal is as follows: The smooth tracking eye movement test result judgment module calculates the average tracking deviation Z of the right eye during the vertical smooth tracking eye movement test. vr Total number of rapid eye movements (REMs) in the right eye (C) vr The total amplitude of rapid eye movement (REM) of the right eye F vr When Z vr >PZ2, or C vr >PC2, or F vr When Z > PF2, it is judged as abnormal right eye vertical smooth tracking eye movement test data; when Z vr ≤PZ2, and C vr ≤PC2, and F vr When the value is ≤PF2, the right eye's vertical smooth tracking eye movement test data is considered normal.

[0023] Preferably, PZ2 > PZ1, PC2 > PC1, and PF2 > PF1.

[0024] Preferably, in the smooth eye movement tracking result judgment module, the method for judging the inconsistency of the eye movement trajectories of the two eyes is any one of the following methods:

[0025] Method 1: Set a distance threshold S1. If the average distance between the coordinates of the eye movement points of both eyes is greater than S1 during horizontal smooth eye movement testing or vertical smooth eye movement testing, it is determined that the eye movement trajectories of both eyes are inconsistent.

[0026] Method 2: Set a proportional threshold S2. If C is used during horizontal smooth eye movement testing... hl and C hrIf the ratio of the smaller value to the larger value is less than S2, it indicates inconsistency in binocular eye movement trajectories; if C is found during vertical smooth eye movement testing... vl and C vr If the ratio of the smaller value to the larger value is less than S2, it indicates that the eye movement trajectories of the two eyes are inconsistent.

[0027] Method 3: Set a proportional threshold S3. If the horizontal smoothness during eye movement testing is... hl and F hr If the ratio of the smaller value to the larger value is less than S3, it indicates inconsistency in binocular eye movement trajectories; if F is found during vertical smooth eye movement testing... vl and F vr If the ratio of the smaller value to the larger value is less than S3, it indicates that the eye movement trajectories of the two eyes are inconsistent.

[0028] Preferably, in the smooth eye movement tracking test result judgment module, 0.5°≤S1≤1.5°, 70%≤S2≤90%, and 70%≤S3≤90%.

[0029] Preferably, the system also includes an auxiliary diagnostic module. If the smooth eye-tracking test result judgment module determines that the subject's smooth eye-tracking test result is abnormal, the auxiliary diagnostic module determines that the subject has a high risk of having a depressive disorder. If the smooth eye-tracking test result judgment module determines that the subject's smooth eye-tracking test result is normal, the auxiliary diagnostic module determines that the subject has a low risk of having a depressive disorder.

[0030] Preferably, the device also includes a fixation module and a saccade module. The fixation module calculates the number of square wave jumps in the left and right eyes during the fixation eye movement test and sets a threshold S4. If the number of square wave jumps in the left eye per unit time is ≥ S4 and the number of square wave jumps in the right eye per unit time is ≥ S4, it is determined that there is an abnormality in square wave jumps during the fixation eye movement test. The saccade module calculates the number of visual distance discrepancies in the left and right eyes during the saccade eye movement test and sets a ratio threshold S5. If the ratio of the number of visual distance discrepancies in the left eye divided by the total number of target jumps is ≥ S5 and the ratio of the number of visual distance discrepancies in the right eye divided by the total number of target jumps is ≥ S5, it is determined that there is an abnormality in visual distance discrepancies during the saccade eye movement test.

[0031] Preferably, the fixation module sets a threshold S4 = 2 times. If the number of square wave jumps in the left eye is ≥ 2 times per 10 seconds and the number of square wave jumps in the right eye is ≥ 2 times per 10 seconds, it is judged that there is an abnormality of square wave jumps during fixation eye movement examination. The saccade module sets a proportion threshold S5 = 20%. If the ratio of the number of poor visual distance recognition in the left eye to the total number of target jumps is ≥ 20% and the ratio of the number of poor visual distance recognition in the right eye to the total number of target jumps is ≥ 20%, it is judged that there is an abnormality of poor visual distance recognition during saccade eye movement examination.

[0032] Preferably, it also includes a risk level assessment module, which assesses the risk level of the subject having a depressive disorder, by means of:

[0033] Level I risk: One of the horizontal smooth eye movement test results and the other of the vertical smooth eye movement test results is abnormal and normal; there is no square wave jump abnormality in fixation eye movement test and no visual distance abnormality in saccade eye movement test.

[0034] Level II risk: Two of the following four items are present: abnormal results in horizontal smooth eye movement test, abnormal results in vertical smooth eye movement test, abnormal square wave jump in fixation eye movement test, and abnormal visual distance in saccade eye movement test. In addition, at least one of the two items, abnormal results in horizontal smooth eye movement test and abnormal results in vertical smooth eye movement test, is present.

[0035] Level III risk: Three out of the following four items are present: abnormal results of horizontal smooth eye movement test, abnormal results of vertical smooth eye movement test, abnormal square wave jump in fixation eye movement test, and abnormal visual distance in saccade eye movement test.

[0036] Level IV risk: All four of the following are present: abnormal results in horizontal smooth eye movement test, abnormal results in vertical smooth eye movement test, abnormal square wave jump in fixation eye movement test, and abnormal visual distance in saccade eye movement test.

[0037] The higher the risk level, the higher the risk of the examinee having a depressive disorder.

[0038] Preferably, it also includes a head fixation bracket for fixing the subject's head during eye movement examination.

[0039] Compared with existing technologies, the beneficial effects of this invention are: it can perform horizontal and vertical smooth eye-tracking tests on subjects, and by recording and comparing the eye-tracking data of both eyes, it effectively eliminates abnormal eye-tracking data caused by non-central nervous system pathway dysfunctions, such as eyelashes obscuring the pupil, eyelids obscuring the pupil, lens reflection, and eye diseases. This allows the smooth eye-tracking test results to more accurately reflect whether the function of the smooth eye-tracking central nervous system pathway is abnormal, thereby improving the accuracy of screening or assisting in the diagnosis of depressive disorders through smooth eye-tracking tests and reducing the false positive rate. Furthermore, this invention can also assess the risk level of subjects suffering from depressive disorders. Attached Figure Description

[0040] Figure 1(a) shows the target trajectory during horizontal smooth eye movement tracking, and Figure 1(b) shows the target trajectory during vertical smooth eye movement tracking.

[0041] Figure 2(a) shows the eye movement trajectory of subject A's left eye in the horizontal smooth eye movement test; Figure 2(b) shows the eye movement trajectory of subject A's right eye in the horizontal smooth eye movement test; Figure 2(c) shows the eye movement trajectory of subject A's left eye in the vertical smooth eye movement test; and Figure 2(d) shows the eye movement trajectory of subject A's right eye in the vertical smooth eye movement test.

[0042] Figure 3(a) shows the eye movement trajectory of subject B's left eye in the horizontal smooth eye movement test; Figure 3(b) shows the eye movement trajectory of subject B's right eye in the horizontal smooth eye movement test; Figure 3(c) shows the eye movement trajectory of subject B's left eye in the vertical smooth eye movement test; and Figure 3(d) shows the eye movement trajectory of subject B's right eye in the vertical smooth eye movement test.

[0043] Figure 4(a) shows the eye movement trajectory of subject C's left eye in the horizontal smooth eye movement test; Figure 4(b) shows the eye movement trajectory of subject C's right eye in the horizontal smooth eye movement test; Figure 4(c) shows the eye movement trajectory of subject C's left eye in the vertical smooth eye movement test; and Figure 4(d) shows the eye movement trajectory of subject C's right eye in the vertical smooth eye movement test.

[0044] Figure 5(a) shows the eye movement trajectory of subject D's left eye in the horizontal smooth eye movement test; Figure 5(b) shows the eye movement trajectory of subject D's right eye in the horizontal smooth eye movement test; Figure 5(c) shows the eye movement trajectory of subject D's left eye in the vertical smooth eye movement test; and Figure 5(d) shows the eye movement trajectory of subject D's right eye in the vertical smooth eye movement test.

[0045] Figure 6(a) shows the eye movement trajectory of subject E's left eye in the horizontal smooth eye movement test; Figure 6(b) shows the eye movement trajectory of subject E's right eye in the horizontal smooth eye movement test; Figure 6(c) shows the eye movement trajectory of subject E's left eye in the vertical smooth eye movement test; and Figure 6(d) shows the eye movement trajectory of subject E's right eye in the vertical smooth eye movement test.

[0046] Figure 7(a) shows the eye movement trajectory of subject Xu's left eye in the horizontal smooth eye movement test; Figure 7(b) shows the eye movement trajectory of subject Xu's right eye in the horizontal smooth eye movement test; Figure 7(c) shows the eye movement trajectory of subject Xu's left eye in the vertical smooth eye movement test; and Figure 7(d) shows the eye movement trajectory of subject Xu's right eye in the vertical smooth eye movement test.

[0047] Figure 8 This is a left eye movement trajectory diagram from a fixation eye movement test of a healthy person.

[0048] Figure 9 This is a left eye movement trajectory diagram from a fixation eye movement test of a patient with a depressive disorder.

[0049] Figure 10(a) shows the left eye movement trajectory (horizontal component) of a healthy person during a saccade eye movement test, and Figure 10(b) shows the left eye movement trajectory (vertical component) of a healthy person during a saccade eye movement test.

[0050] Figure 11(a) shows the left eye movement trajectory (horizontal component) of a patient with depressive disorder during a saccade eye movement test, and Figure 11(b) shows the left eye movement trajectory (vertical component) of a patient with depressive disorder during a saccade eye movement test. Detailed Implementation

[0051] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0052] Example 1

[0053] This embodiment discloses an eye-tracking examination device, including a display module, a near-infrared image acquisition module, a calibration module, an eye-tracking point calculation module, and a smooth-tracking eye-tracking result judgment module. It also includes a computer, on which the calibration module, eye-tracking point calculation module, and smooth-tracking eye-tracking result judgment module are programs running. Additionally, this embodiment includes an auxiliary display that can display in real-time information such as the subject's left-eye image, left-eye eye-tracking point coordinates, right-eye image, right-eye eye-tracking point coordinates, and optotype coordinates, allowing doctors to view the eye-tracking examination process and results in real time. This embodiment also uses a head-fixation bracket to stabilize the subject's head during the eye-tracking examination, facilitating more accurate eye-tracking point calculation results.

[0054] In this embodiment, the display module is a monitor connected to a computer, capable of displaying two modes. Mode 1 is a horizontal smooth eye-tracking test, where a target moves smoothly horizontally along the display module. The trajectory of the target's movement is controlled by a program, and the target's position at each moment is known. Mode 2 is a vertical smooth eye-tracking test, where a target moves smoothly vertically along the display module. The target's trajectory is also controlled by a program, and the target's position at each moment is known. During the target movement, the user's eyes are required to follow the target's movement. In both the horizontal and vertical smooth eye-tracking tests, the target can be seen by both the left and right eyes simultaneously.

[0055] In this embodiment, the near-infrared image acquisition module includes one near-infrared camera and two near-infrared light sources. The two near-infrared light sources are located on either side of the near-infrared camera. The near-infrared camera and near-infrared light sources are housed inside the casing, below the display module. The near-infrared camera is connected to a computer via a USB data cable. The near-infrared image acquisition module can simultaneously capture images of the left and right eyes. In this embodiment, the near-infrared camera in the near-infrared image acquisition module is set to capture 100 frames of eye images per second, that is, one frame of eye image is captured every 10ms. Correspondingly, the eye movement point calculation module calculates the eye movement point coordinates in real time every 10ms. The calculated eye movement point coordinates can be displayed in real time on the doctor's auxiliary display and are also stored in the computer database for statistical analysis.

[0056] In this embodiment, the calibration module is used to calibrate the left and right eyes, obtaining the left eye calibration function through the left eye calibration and the right eye calibration function through the right eye calibration.

[0057] In this embodiment, the eye-tracking point calculation module is used to calculate the coordinates of the left and right eye-tracking points. After the left and right eye calibrations are completed, the left eye-tracking point coordinates are calculated based on the left eye image captured by the near-infrared image capturing module and the left eye calibration function, and the right eye-tracking point coordinates are calculated based on the right eye image captured by the near-infrared image capturing module and the right eye calibration function.

[0058] The process of calibration and eye-tracking point calculation is as follows:

[0059] Because the near-infrared camera in the near-infrared image acquisition module captures corneal reflective points with high brightness (up to 255 gray levels), and two corneal reflective points appear in pairs and are close together, the image regions containing the left and right eyes can be located from the entire image captured by the near-infrared camera based on this characteristic. A gray level threshold is set that is higher than the pupil's gray level but lower than the gray level of the surrounding iris and skin area; areas below this gray level are marked as possible pupil regions. Then, an area threshold is set to exclude interference from small black objects such as eyelashes, thereby determining the accurate region where the pupil is located. The coordinates of the left eye pupil center are obtained from the center of the left eye pupil region; the coordinates of the left eye corneal reflective point center are obtained from the average coordinates of the two corneal reflective point centers. The left eye pupil corneal vector is obtained by subtracting the left eye corneal reflective point center coordinates from the left eye pupil center coordinates. Similarly, the right eye pupil center coordinates, the coordinates of the two corneal reflective point centers, and the right eye pupil corneal vector can be obtained.

[0060] This embodiment uses a 9-point calibration, displaying calibration points at nine locations on the display: center, left, right, top, bottom, upper left, upper right, lower left, and lower right. The positions of these nine points are known and definite. There is a one-to-one correspondence between the pupil-corneal vector of the subject's left eye and the coordinates of the left eye movement point on the display; this is called the left eye calibration function. Similarly, there is a one-to-one correspondence between the pupil-corneal vector of the right eye and the coordinates of the right eye movement point on the display; this is called the right eye calibration function.

[0061] Taking the left eye as an example, the calibration process is as follows:

[0062] Let x be the horizontal coordinate of the left eye movement point on the display plane, and y be the vertical coordinate of the left eye movement point on the display plane; let x be the horizontal value of the left eye pupil corneal vector, and y be the vertical value of the left eye pupil corneal vector. The left eye pupil corneal vector is obtained from the camera image, and its unit is pixels.

[0063] Use the following calibration function:

[0064]

[0065] The 12 values ​​a0, a1, a2, a3, a4, a5, b0, b1, b2, b3, b4, and b5 are unknown before calibration. Calibration is the process of solving for these 12 unknowns.

[0066] Because the coordinates (x, y) of the 9 calibration points on the display plane s1 ,y s1 ), (x s2 ,y s2 ), (x s3 ,y s3 ), (x s4 ,y s4 ), (x s5 ,y s5 ), (x s6 ,y s6 ), (x s7 ,y s7 ), (x s8 ,y s8 ), (x s9 ,y s9 The following is known; the left eye image captured by the near-infrared camera in the near-infrared image acquisition module can be used to calculate that the left eye pupil-corneal vectors when viewing these 9 calibration points are respectively (x... e1 ,y e1 ), (x e2 ,y e2 ), (x e3 ,y e3 ), (x e4 ,y e4 ), (xe5 ,y e5 ), (x e6 ,y e6 ), (x e7 ,y e7 ), (x e8 ,y e8 ), (x e9 ,y e9 Substituting the values ​​into the calibration function, we obtain the following system of 18 equations:

[0067]

[0068]

[0069] Since the number of equations is greater than the number of unknown variables, the overdetermined system of equations needs to be solved using the least squares method to obtain the least squares solution a0,a1,a2,a3,a4,a5,b0,b1,b2,b3,b4,b5.

[0070] After the left eye calibration is completed, since a0, a1, a2, a3, a4, a5, b0, b1, b2, b3, b4, and b5 have all been solved to known values, the left eye calibration function is obtained. When the subject looks at any position on the display module, the eye-tracking point calculation module can calculate the left eye pupil-corneal vector (x) in real time. e ,y e Substituting this into the left-eye calibration function, the coordinates (x, y) of the subject's left-eye position on the display module can be calculated in real time. s ,y s This refers to the coordinates of the left eye movement point. A similar method can be used to calibrate the right eye, obtain the right eye calibration function, and calculate the coordinates of the right eye movement point.

[0071] In this embodiment, the coordinates of the eye-tracking point are based on the midpoint of the display as the origin (0, 0), with the right side of the horizontal direction as the positive X-axis and the top of the vertical direction as the positive Y-axis, and the unit is the viewing angle (degrees). In other embodiments, when the distance between the display and the human eye is known, the viewing angle can also be converted into pixels or length units on the display.

[0072] In this embodiment, left-eye and right-eye calibration are performed simultaneously. This is done so that when the calibration points are displayed on the monitor, both eyes can see them. After all nine calibration points have been displayed, the left-eye and right-eye calibration functions are obtained simultaneously. During subsequent eye-tracking tests, the visual targets displayed on the monitor are also visible to both the left and right eyes simultaneously.

[0073] In other embodiments, the near-infrared image acquisition module can also use a binocular camera system. Based on the principle of binocular vision, the eye-tracking point calculation module calculates the three-dimensional visual axes of the left and right eyes separately after single-point calibration. Then, it obtains the coordinates of the left and right eye-tracking points by calculating the intersection of the visual axes and the display plane. In other embodiments, the near-infrared image acquisition module can also be a smaller device integrated into a head-mounted device. In other embodiments, a binocular vision system such as red-blue glasses can be used to calibrate the left and right eyes separately.

[0074] Taking examinee A as an example, the eye movement examination process is as follows:

[0075] (I) Subject A sits in front of the eye-tracking equipment, resting his chin on the head support, with his eyes facing the monitor. The near-infrared imaging module is located directly below the monitor. The subject's eyes are 60 cm away from the monitor. The near-infrared camera in the near-infrared imaging module is set to capture 100 frames of eye images per second, i.e., one frame of eye image is captured every 10 ms. After the 9-point calibration is completed, the calibration module calculates the calibration functions for the left and right eyes. The eye-tracking point calculation module performs real-time calculations using image processing algorithms, calculating the coordinates of the left eye movement point based on the left eye image captured by the near-infrared imaging module and the left eye calibration function, and calculating the coordinates of the right eye movement point based on the right eye image captured by the near-infrared imaging module and the right eye calibration function. Each frame of left eye movement point data includes the acquisition time of that frame and the corresponding coordinates of the left eye movement point; each frame of right eye movement point data includes the acquisition time of that frame and the corresponding coordinates of the right eye movement point.

[0076] (II) Performing a smooth horizontal eye-tracking test. The computer controls the smooth horizontal movement of the optotype on the monitor. The trajectory of this smooth movement is continuous and uninterrupted. In this embodiment, the optotype is a small white dot with a diameter of 1° of visual angle, and the background color of the monitor is gray. The doctor can instruct the examinee to follow the optotype continuously using the following instructions: "The dot on the screen will move left and right; please follow it with your eyes." The instructions can also be played automatically by the device. After the smooth horizontal eye-tracking test begins, the optotype first appears at the center of the monitor screen, then moves horizontally to the right at a constant speed of 8° / s. When it reaches 10° to the right, it moves horizontally to the left at a constant speed of 8° / s, and then back to the center, completing one cycle. Each cycle lasts 5 seconds. After 20 seconds, i.e., after completing 4 cycles of smooth horizontal movement, the optotype stops moving, and the smooth horizontal eye-tracking test ends.

[0077] Plotting time as the x-axis (unit: ms) and the horizontal displacement of the target as the y-axis (0 point in the middle, positive on the right, negative on the left, unit: visual angle °), a function graph of the target displacement over time can be obtained, i.e., the target trajectory graph, as shown in Figure 1(a), which is a triangular wave changing with time. During the horizontal smoothing eye movement examination, the eye movement point calculation module records the left and right eye movement point data. In this embodiment, the total target movement time is 20 seconds, and one left eye movement point coordinate and one right eye movement point coordinate can be obtained every 10ms. In these 20 seconds, 2000 left eye movement point coordinates and 2000 right eye movement point coordinates can be obtained. Considering the intuitiveness of the eye-tracking diagram, time is used as the X-axis and the horizontal component of the left eye movement point coordinates is used as the Y-axis. By connecting the horizontal component values ​​of the 2000 left eye movement point coordinates, a function graph of the horizontal component of the left eye movement point coordinates changing with time can be obtained, i.e., the left eye-tracking diagram of the horizontal component changing with time, as shown in Figure 2(a). Here, the X-axis represents time (unit: ms), and the Y-axis represents the horizontal component of the eye movement point coordinates (unit: visual angle °). To facilitate comparison of the difference between the eye movement point coordinates and the optotype coordinates at different times, the optotype trajectory diagram is also displayed simultaneously; the optotype trajectory diagram is the triangular wave shown in the figure. Similarly, the right eye-tracking diagram of the horizontal component of the right eye movement point coordinates changing with time can be obtained, as shown in Figure 2(b). Generally, during horizontal smooth eye movement testing, the vertical component of the subject's eye movement point and the vertical component of the visual target coordinates are not significantly different. Therefore, during horizontal smooth eye movement testing, the focus can be on displaying and analyzing the eye movement trajectory diagram showing the change of the horizontal component of the eye movement point coordinates over time.

[0078] In other embodiments, when the target moves at a constant speed in the horizontal direction, the number of cycles of movement, the speed of movement, the range of movement, the starting point and the ending point of movement can be set.

[0079] (III) Perform vertical smooth eye-tracking examination. The central neural pathways for horizontal and vertical smooth eye-tracking overlap to some extent, and there are also some differences in certain areas. Therefore, by performing horizontal and vertical smooth eye-tracking examinations in sequence, the function of the central neural pathways related to smooth eye-tracking can be reflected more comprehensively and completely.

[0080] The computer controls the smooth vertical movement of the optotype on the monitor. This smooth movement is continuous and uninterrupted. In this embodiment, the optotype is a small white dot with a diameter of 1° of viewing angle, and the monitor background is gray. The doctor can instruct the examinee to follow the optotype's movement with their eyes. The instructions are: "The dot on the screen will move up and down; please follow it with your eyes." These instructions can also be played automatically by the device. After the vertical smooth eye-tracking test begins, the optotype first appears at the center of the monitor screen, then moves vertically upwards at a constant speed of 8° / s. When it reaches 10° upwards, it moves vertically downwards at a constant speed of 8° / s, and then moves horizontally upwards at a constant speed of 8° / s when it reaches 10° downwards. Returning to the center completes one cycle, each cycle lasting 5 seconds. After 20 seconds, having completed four cycles of smooth vertical movement, the optotype stops moving, and the vertical smooth eye-tracking test ends.

[0081] Plotting time as the x-axis (unit: ms) and the vertical displacement of the target as the y-axis (0 at the center, positive at the top, negative at the bottom, unit: visual angle °), a function graph of the target displacement over time can be obtained, i.e., the target trajectory graph, as shown in Figure 1(b), which is a triangular wave changing with time. During the vertical smooth eye movement examination, the eye movement point calculation module records the left and right eye movement point data. In this embodiment, the total target movement time is 20 seconds, and one left eye movement point coordinate and one right eye movement point coordinate can be obtained every 10ms. In these 20 seconds, 2000 left eye movement point coordinates and 2000 right eye movement point coordinates can be obtained. Considering the intuitiveness of eye-tracking diagrams, by plotting time as the X-axis and the vertical component of the left eye movement point coordinates as the Y-axis, connecting the vertical component values ​​of these 2000 left eye movement point coordinates yields a function graph showing the change of the vertical component of the left eye movement point coordinates over time, i.e., the left eye movement trajectory diagram showing the change of the vertical component over time, as shown in Figure 2(c). Similarly, the right eye movement trajectory diagram showing the change of the vertical component of the right eye movement point coordinates over time can be obtained, as shown in Figure 2(d). Generally, during vertical smooth eye movement testing, the horizontal component of the subject's eye movement point coordinates and the horizontal component of the target coordinates are not significantly different. Therefore, during vertical smooth eye movement testing, the focus can be on displaying and analyzing the eye movement trajectory diagram showing the change of the vertical component of the eye movement point coordinates over time.

[0082] In other embodiments, when the target moves at a constant speed in the vertical direction, the number of cycles of movement, the speed of movement, the range of movement, the starting point and the ending point of movement can be set.

[0083] The order of horizontal smooth eye-tracking examination and vertical smooth eye-tracking examination can be interchanged.

[0084] (iv) Interpretation of smooth tracking eye movement test results

[0085] The smooth eye movement tracking test result judgment module first determines whether the horizontal smooth eye movement tracking test data of the left eye and the right eye are normal or abnormal.

[0086] In this embodiment, the method for determining whether the horizontal smoothing eye movement tracking data of the left eye is normal or abnormal is as follows: Set judgment thresholds PZ1, PC1, and PF1 for the horizontal smoothing eye movement tracking test. The smoothing eye movement tracking test result judgment module calculates the average tracking deviation Z of the left eye during the horizontal smoothing eye movement tracking test. hl Total number of rapid eye movements (REMs) in the left eye (C) hl The total amplitude of rapid eye movement (REM) of the left eye is F hl When Z hl >PZ1, or C hl >PC1, or F hl When Z > PF1, it is judged as abnormal in the left eye horizontal smooth tracking eye movement test data. hl ≤PZ1, and C hl ≤PC1, and F hl When the value is ≤PF1, the data of the left eye horizontal smooth tracking eye movement test is considered normal.

[0087] The average tracking deviation Z of the left eye movement point data hl The calculation method is as follows: After the horizontal smooth eye-tracking test begins, i.e. after the target begins to move, calculate the distance between the coordinates of the left eye movement point and the corresponding time target coordinates in each frame of left eye movement point data. This distance is accumulated during the test, and the total deviation distance L is obtained after the test. Let M be the total number of frames of left eye movement point data in this test, then Z... hl = L ÷ M. In this embodiment, since the test time is 20 seconds and 100 frames of left eye movement data are obtained per second, the total number of frames of left eye movement data is M = 2000.

[0088] The total number of rapid eye movements (C) in the left eye movement point data. hlThe calculation method is as follows: After the horizontal smooth eye movement test begins, the eye movement velocity of each frame of left-eye eye movement point data is calculated sequentially according to the time order. Starting from the second frame, for the left-eye eye movement point data of the Nth frame, the distance between the left-eye eye movement point coordinates of this frame and the left-eye eye movement point coordinates of the (N-1)th frame is defined as the eye movement distance of this frame's left-eye eye movement point data. Let Δt be the interval between the image acquisition time of this frame's left-eye eye movement point data and the image acquisition time of the (N-1)th frame's left-eye eye movement point data. The eye movement velocity of this frame's left-eye eye movement point data is defined as equal to the eye movement distance of this frame's left-eye eye movement point data divided by Δt. In this embodiment, Δt between every two frames is a fixed time value of 10ms; a velocity threshold V is set, and a distance threshold is set. The value D is used to define a frame of left-eye eye movement data as a fast eye movement data frame when the eye movement velocity of the left eye is greater than V, and as a slow eye movement data frame when the eye movement velocity of the left eye is less than or equal to V. If there are several consecutive frames of fast eye movement data between two frames of slow eye movement data, and the sum of the eye movement distances of these left-eye eye movement data is greater than D, it is recorded as one fast eye movement, and the sum of the eye movement distances of these fast eye movement data is recorded as the amplitude of this fast eye movement. If there is only one frame of fast eye movement data between two frames of slow eye movement data, and the eye movement distance of this fast eye movement data is greater than D, it is also recorded as one fast eye movement, and the eye movement distance of this fast eye movement data is recorded as the amplitude of this fast eye movement. The first frame of left-eye eye movement data at the start of the test can be defined as slow eye movement data, and the last frame at the end of the test can be defined as slow eye movement data. After the test begins, the number of rapid eye movements (REMs) is accumulated. At the end of the test, the total number of REMs in the left eye is obtained, denoted as C. hlThe velocity threshold V should be set to a value greater than the maximum smooth movement speed of the target point. In this embodiment, the smooth movement speed of the target point is 8° / second. Considering the influence of image processing measurement noise and the inherent slight tremors of the eye, the velocity threshold V should generally be set to be more than 10° / second greater than the maximum smooth movement speed of the target point to prevent noise or inherent slight tremors of the eye from being misjudged as rapid eye movements. In this embodiment, the velocity threshold V = 30° / second. The distance threshold D should be set to be greater than or equal to V multiplied by the image acquisition time interval. In this embodiment, V = 30° / second, and the image acquisition time interval = 10ms, so D should be set to a distance threshold greater than or equal to 0.3°. The smaller the value of D, the more rapid eye movements may be calculated; the larger the value of D, the fewer rapid eye movements may be calculated. Considering the limitations of monitor resolution or printer resolution, small-amplitude rapid eye movements are not easily perceived by the naked eye. In this embodiment, the distance threshold D = 2°. In other embodiments, dividing the total number of rapid eye movements (REMs) by the test time yields the number of REMs per unit time, also known as the REM frequency. This is equivalent to the total number of REMs. Similarly, if the target moves smoothly over several cycles, the average number of REMs per cycle can be calculated, which is also equivalent to the total number of REMs.

[0089] The total amplitude of rapid eye movement F in the left eye movement point data hl The calculation method is as follows: After the horizontal smooth eye movement test begins, the amplitude of each left-eye rapid eye movement (REM) is accumulated. At the end of the test, the total accumulated amplitude of the left-eye REM is obtained, which is the total amplitude of the left-eye REM. In other embodiments, if the total REM amplitude is divided by the test time, the REM amplitude per unit time can be obtained, which is interchangeable and equivalent to the total REM amplitude. Similarly, if the target moves smoothly for several cycles, the average REM amplitude per cycle can also be calculated, which is also interchangeable and equivalent to the total REM amplitude.

[0090] The method for determining whether the horizontal smoothed eye movement test results for the right eye are normal or abnormal in the smoothed eye movement test module is similar to that for the left eye. Simply replace the left eye movement data with the right eye movement data, and then calculate the average tracking deviation Z of the right eye during the horizontal smoothed eye movement test using a similar method. hr Total number of rapid eye movements (REMs) in the right eye (C) hr The total amplitude of rapid eye movement (REM) of the right eye F hr When Z hr >PZ1, or C hr >PC1, or F hrWhen Z > PF1, it is judged as abnormal in the right eye horizontal smooth tracking eye movement test data. hr ≤PZ1, and C hr ≤PC1, and F hr When the value is ≤PF1, the data of the right eye horizontal smooth tracking eye movement test is considered normal.

[0091] The smooth eye movement test result judgment module then judges whether the vertical smooth eye movement test data of the left eye and the right eye are normal or abnormal.

[0092] Taking the left-eye vertical smooth tracking eye movement test as an example, the method for determining whether the left-eye vertical smooth tracking eye movement test result is normal or abnormal is as follows: Set the judgment thresholds PZ2, PC2, and PF2 for the vertical smooth tracking eye movement test. During the vertical smooth tracking eye movement test, the smooth tracking eye movement data judgment module calculates the average tracking deviation Z of the left eye. vl Total number of rapid eye movements (REMs) in the left eye (C) vl Total amplitude of rapid eye movement (REM) of the left eye F vl When Z vl >PZ2, or C vl >PC2, or F vl When Z > PF2, it is judged as an abnormal result in the left eye vertical smooth tracking eye movement test. vl ≤PZ2, and C vl ≤PC2, and F vl When the value is ≤PF2, the result of the left eye vertical smooth tracking eye movement test is considered normal.

[0093] The method for determining whether the right eye's vertical smooth tracking eye movement test results are normal or abnormal in the smooth tracking eye movement test module is similar to that for the left eye. Simply replace the left eye movement point data with the right eye movement point data, and then calculate the right eye's average tracking deviation Z during the vertical smooth tracking eye movement test using a similar method. vr Total number of rapid eye movements (REMs) in the right eye (C) vr The total amplitude of rapid eye movement (REM) of the right eye F vr When Z vr >PZ2, or C vr >PC2, or F vr When Z > PF2, it is judged as abnormal in the right eye vertical smooth tracking eye movement test data. vr ≤PZ2, and C vr ≤PC2, and F vr When the value is ≤PF2, the right eye's vertical smooth tracking eye movement test data is considered normal.

[0094] The average tracking deviation reflects the average error between the eye movement point and the target during smooth eye movement testing. A large average tracking deviation often indicates that the subject cannot accurately track the target smoothly. If the target moves smoothly at a fast speed, the judgment thresholds PZ1 and PZ2 for horizontal and vertical smooth eye movement testing can be larger; if the target moves smoothly at a slow speed, PZ1 and PZ2 can be smaller. The values ​​of PZ1 and PZ2 are generally between 1° and 2°. Statistical analysis of clinical data shows that most subjects have an average tracking deviation greater than that for horizontal smooth eye movement testing; therefore, PZ2 can be set to a value greater than PZ1. In this embodiment, PZ1 is set to 1.2° and PZ2 is set to 1.5°.

[0095] The total number of rapid eye movements (REMs) quantitatively reflects the subject's control over the speed of smooth eye movement tracking. A large number of REMs often indicates that the subject cannot smoothly and stably track the target, and there are more deviations, resulting in more square or step-like eye movements. If the target moves smoothly at a fast speed, the judgment thresholds PC1 and PC2 for horizontal and vertical smooth eye movement tests can be set to larger values; if the target moves smoothly at a slow speed, PC1 and PC2 can be set to smaller values. When the test time is 20 seconds, the values ​​of PC1 and PC2 are generally between 10 and 30 times. Statistical analysis of clinical data shows that most subjects have a higher total number of REMs in vertical smooth eye movement tests than in horizontal smooth eye movement tests; therefore, PC2 can be set to a value greater than PC1. In this embodiment, PC1 is set to 16 times and PC2 is set to 20 times. If the test time is longer or shorter than 20 seconds, the threshold settings for PC1 and PC2 can be adjusted proportionally.

[0096] The total amplitude of rapid eye movements (REM) quantitatively reflects the subject's ability to control the speed of smooth eye movement tracking. A large total REM amplitude often indicates that the subject cannot smoothly and stably track the target, and the deviation is significant, often resulting in a large-amplitude square or step-like eye trajectory. If the target moves smoothly at a fast speed, the judgment thresholds PF1 for horizontal smooth eye movement tracking and PF2 for vertical smooth eye movement tracking can be larger; conversely, if the target moves slowly, PF1 and PF2 can be smaller. When the test duration is 20 seconds, the values ​​of PF1 and PF2 are generally between 30° and 100°. Most subjects have a higher total REM amplitude in vertical smooth eye movement tracking than in horizontal smooth eye movement tracking; therefore, PF2 can be set to a value greater than PF1. In this embodiment, PF1 is set to 60° and PF2 to 75°. If the test time is longer or shorter than 20 seconds, the threshold settings for PF1 and PF2 can be adjusted proportionally.

[0097] Using the above methods, the Z-axis of the left eye during the subject's horizontal smooth eye movement test can be calculated. hl =1.57° (>PZ1), left eye C hl =22 times (>PC1), left eye F hl =112.48° (>PF1), right eye Z hr =1.48° (>PZ1), right eye C hr =22 times (>PC1), right eye F hr =111.26° (>PF1), therefore it can be determined that the horizontal smooth tracking eye movement test data of subject A's left eye is abnormal and the horizontal smooth tracking eye movement test data of the right eye is abnormal.

[0098] Using the above methods, the Z-axis of the left eye during the vertical smooth eye movement test of the subject can be calculated. vl =2.38° (>PZ2), left eye C vl =29 times (>PC2), left eye F vl =182.04° (>PF2), right eye Z vr =2.56° (>PZ2), right eye C vr =28 times (>PC2), right eye F vr =173.46° (>PF2), therefore it can be determined that the vertical smooth tracking eye movement test data of subject A's left eye is abnormal and the vertical smooth tracking eye movement test data of the right eye is abnormal.

[0099] Through observation and analysis of clinical eye movement examination data, it was found that the reasons for abnormalities in horizontal or vertical smooth tracking eye movement examination data can be mainly divided into the following two categories.

[0100] The first type of cause: Abnormal smooth eye-tracking data is due to dysfunction in the central neural pathways involved in smooth eye-tracking. The main central neural pathways related to smooth eye-tracking are: the brain (including the frontal lobe oculomotor area, supplementary oculomotor area, and parts of the temporal, parietal, and occipital lobes) receives visual information from both eyes, analyzes and integrates it, and sends nerve impulses. These impulses first descend to the dorsolateral pontine nucleus in the brainstem, then to the flocculus and vermis of the cerebellum, and the medial vestibular nuclei in the brainstem. The cerebellum regulates the speed of smooth tracking, maintaining synchronous movement between the eyeball and the stimulus. The basal ganglia and superior colliculus also play a role in the control of smooth eye-tracking. Finally, eye movement is controlled through the oculomotor nucleus, trochlear nucleus, and abducens nucleus in the brainstem. Therefore, smooth eye-tracking requires the coordinated operation of multiple areas of the central neural pathway. If one or more areas of this pathway malfunction, it can lead to abnormal smooth eye-tracking data.

[0101] The second type of cause: Abnormal smooth eye movement test data is due to abnormalities in the central neural pathways of non-smooth eye movement, such as eyelashes obscuring the pupil, eyelids obscuring the pupil, lens reflection, and eye diseases (such as strabismus and oculomotor paralysis). Because the calculated coordinates of the eye movement point are directly related to the calculated coordinates of the pupil center and the corneal reflector center, if the pupil is obscured by eyelashes or eyelids, it may lead to deviations in the calculation of the pupil center coordinates, resulting in abnormal smooth eye movement tracking data. Similarly, if the lens reflection is located in the pupillary region, it may also cause deviations in the calculation of the pupil center coordinates, leading to abnormal smooth eye movement tracking data. Furthermore, the lens reflection may be located in the area where the corneal reflector is located, causing deviations in the calculation of the corneal reflector center coordinates, resulting in abnormal smooth eye movement tracking data. Some strabismus patients have intermittent or alternating strabismus, which may lead to abnormal smooth eye movement tracking data. Patients with oculomotor palsy often experience restricted eye movement in a certain direction due to oculomotor abnormalities, resulting in abnormal smooth eye movement tracking data. These types of abnormal smooth eye movement tracking data are clearly unrelated to abnormalities in the central nervous pathway for smooth eye movement tracking.

[0102] The intended purpose of this eye-tracking testing device is that normal smooth tracking eye movement test results reflect normal function of the central nervous system pathway for smooth tracking eye movement, while abnormal smooth tracking eye movement test results reflect abnormal function of the central nervous system pathway for smooth tracking eye movement. Therefore, if abnormal smooth tracking eye movement test data is found, it is necessary to rule out the second type of cause as much as possible.

[0103] According to the physiological mechanism of eye movements, under normal circumstances, both eyes move in conjugate motion, meaning they move synchronously and their eye movement trajectories should be consistent. Through observation and analysis of clinical eye movement examination data, the first type of abnormality in smooth tracking eye movement data—namely, abnormal function of the central neural pathway for smooth tracking eye movements—generally does not lead to asynchronous eye movements; the eye movement trajectories of both eyes are consistent. In the second type of abnormality in smooth tracking eye movement data, eye diseases (strabismus, oculomotor palsy) can cause asynchronous eye movements, resulting in inconsistent eye movement trajectories. In this second type of abnormality, interfering factors such as eyelashes obscuring the pupil, eyelids obscuring the pupil, and lens reflections will interfere with the smooth tracking eye movement data, either in one eye or both eyes. If only one eye is affected, it will lead to inconsistent eye movement trajectories. If both eyes are affected, because the interference occurs randomly, the degree of interference is generally different between the two eyes, which will also lead to inconsistent eye movement trajectories. Based on the above patterns, it is possible to distinguish whether the abnormality in smooth eye-tracking test data is due to the first or second type of cause.

[0104] Taking the horizontal smooth eye-tracking test as an example, if the horizontal smooth eye-tracking test data of the left eye is abnormal and the horizontal smooth eye-tracking test data of the right eye is abnormal, and the eye movement trajectories of both eyes are consistent, it can be determined that the reason for the abnormal smooth eye-tracking test data is the first type of reason, that is, the function of the central neural pathway of horizontal smooth eye-tracking. The judgment result of the smooth eye-tracking test result judgment module is: the horizontal smooth eye-tracking test result is abnormal.

[0105] If the horizontal smooth eye movement tracking test data for both the left and right eyes is normal, the result of the smooth eye movement tracking test result judgment module is: the horizontal smooth eye movement tracking test result is normal.

[0106] If the horizontal smooth eye movement tracking data for one eye is normal, while the data for the other eye is abnormal, this indicates inconsistency in the eye movement trajectories. The abnormal data can be attributed to the second type of cause, such as eyelashes obscuring the pupil, eyelids obscuring the pupil, or eye diseases. However, the central neural pathway for horizontal smooth eye movement tracking is functioning normally. Therefore, the judgment from the smooth eye movement tracking result judgment module is: the horizontal smooth eye movement tracking result is normal.

[0107] If both eyes show abnormal horizontal smooth eye-tracking data, and the eye movements are inconsistent, this indicates a second type of cause. However, the presence of a first type of cause is uncertain. Therefore, this situation cannot determine whether the central nervous pathway function of the horizontal smooth eye-tracking test is normal or abnormal. The result of the smooth eye-tracking test result judgment module is: horizontal smooth eye-tracking test result is invalid. In actual clinical eye-tracking examinations, this situation occurs relatively rarely. If it does occur, the horizontal smooth eye-tracking test can be repeated until a valid result is obtained. If multiple horizontal smooth eye-tracking tests are still invalid, the horizontal smooth eye-tracking test for this subject can be abandoned.

[0108] Similarly, in the vertical smooth tracking eye movement test, if the vertical smooth tracking eye movement test data of the left eye is abnormal and the vertical smooth tracking eye movement test data of the right eye is abnormal, and the eye movement trajectories of both eyes are consistent, the judgment result of the smooth tracking eye movement test result judgment module is: the vertical smooth tracking eye movement test result is abnormal.

[0109] If the vertical smooth following eye movement test data for the left eye is normal and the vertical smooth following eye movement test data for the right eye is normal, the judgment result of the smooth following eye movement test result judgment module is: the vertical smooth following eye movement test result is normal.

[0110] If the vertical smooth following eye movement test data for the left eye is normal or the vertical smooth following eye movement test data for the right eye is normal, the judgment result of the smooth following eye movement test result judgment module is: the vertical smooth following eye movement test result is normal.

[0111] If the vertical smooth following eye movement test data for the left eye is abnormal and the vertical smooth following eye movement test data for the right eye is abnormal, and the movement trajectories of the two eyes are inconsistent, the judgment result of the smooth following eye movement test result judgment module is: the vertical smooth following eye movement test result is invalid.

[0112] If the subject's horizontal smooth eye movement tracking test result is abnormal or the subject's vertical smooth eye movement tracking test result is abnormal, the smooth eye movement tracking test result judgment module determines that the subject's smooth eye movement tracking test result is abnormal; if the subject's horizontal smooth eye movement tracking test result is normal and the subject's vertical smooth eye movement tracking test result is normal, the smooth eye movement tracking test result judgment module determines that the subject's smooth eye movement tracking test result is normal.

[0113] If the subject's horizontal smooth eye movement tracking test result is invalid and the subject's vertical smooth eye movement tracking test result is invalid, the smooth eye movement tracking test result judgment module determines that the subject's smooth eye movement tracking test result is invalid; if the subject's horizontal smooth eye movement tracking test result is invalid and the subject's vertical smooth eye movement tracking test result is normal, the smooth eye movement tracking test result judgment module determines that the subject's smooth eye movement tracking test result is invalid; if the subject's horizontal smooth eye movement tracking test result is invalid and the subject's vertical smooth eye movement tracking test result is normal, the smooth eye movement tracking test result judgment module determines that the subject's smooth eye movement tracking test result is invalid.

[0114] In the smooth eye-tracking test result judgment module, if both eyes' horizontal smooth eye-tracking test data are abnormal, or both eyes' vertical smooth eye-tracking test data are abnormal, the method to determine inconsistency in the eye movement trajectories can be any of the following methods: Method 1: Set a distance threshold S1. If the average distance between the eye movement point coordinates of both eyes is greater than S1 in the horizontal or vertical smooth eye-tracking test, the eye movement trajectories are determined to be inconsistent. Method 2: Set a ratio threshold S2. If the average distance between the eye movement point coordinates of both eyes is greater than S1 in the horizontal or vertical smooth eye-tracking test, the eye movement trajectories are determined to be inconsistent. hl and C hr If the ratio of the smaller value to the larger value is less than S2, it indicates inconsistency in binocular eye movement trajectories; if C is found during vertical smooth eye movement testing... vl and C vr If the ratio of the smaller value to the larger value is less than S2, it indicates inconsistency in binocular eye movement trajectories; Method 3: Set a ratio threshold S3. If F is found to be inconsistent during horizontal smooth eye movement testing... hl and F hr If the ratio of the smaller value to the larger value is less than S3, it indicates inconsistency in binocular eye movement trajectories; if F is found during vertical smooth eye movement testing... vl and F vr If the ratio of the smaller value to the larger value is less than S3, it indicates that the eye movement trajectories of the two eyes are inconsistent.

[0115] The method for calculating the average distance between the eye movement point coordinates of both eyes is as follows: during horizontal or vertical smooth eye movement tracking tests, the coordinates of the left and right eye movement points are calculated for each frame. Then, the distance between the coordinates of the left and right eye movement points in each frame is calculated and accumulated during the eye movement test. After the eye movement test is completed, the total accumulated distance is divided by the total number of frames to obtain the average distance between the eye movement point coordinates of both eyes.

[0116] The value of S1 can range from 0.5° to 1.5°, and in this embodiment, S1 is set to 1°. The value of S2 can range from 70% to 90%, and in this embodiment, S2 is set to 80%. The value of S3 can range from 70% to 90%, and in this embodiment, S3 is set to 80%.

[0117] If both eyes show abnormal horizontal smooth eye-tracking data, and no inconsistency in eye movement trajectories is found using the above methods, then the eye movement trajectories are considered consistent during the horizontal smooth eye-tracking test. Similarly, if both eyes show abnormal vertical smooth eye-tracking data, and no inconsistency in eye movement trajectories is found using the above methods, then the eye movement trajectories are considered consistent during the vertical smooth eye-tracking test.

[0118] If, during horizontal smooth eye tracking testing, one eye shows normal data while the other eye shows abnormal data, then the eye movement trajectories are considered inconsistent during the horizontal smooth eye tracking test. Similarly, if, during vertical smooth eye tracking testing, one eye shows normal data while the other eye shows abnormal data, then the eye movement trajectories are considered inconsistent during the vertical smooth eye tracking test.

[0119] If the horizontal smooth eye-tracking test data for both eyes are normal, then the eye movement trajectories of both eyes are considered to be consistent during the horizontal smooth eye-tracking test. If the vertical smooth eye-tracking test data for both eyes are normal, then the eye movement trajectories of both eyes are considered to be consistent during the vertical smooth eye-tracking test.

[0120] In addition to the above method where the smooth eye movement test result judgment module automatically judges whether the eye movement trajectories of both eyes are consistent, doctors can also judge whether the eye movement trajectories of both eyes are consistent by observation based on their experience.

[0121] Taking the smoothed eye-tracking examination of six subjects (subjects A, B, C, D, E, and X) as an example, the smoothed eye-tracking examination data and results of these six subjects are shown in Table 1 according to the above judgment method. If the average tracking deviation, the total number of rapid eye movements, and the total amplitude of rapid eye movements are higher than the corresponding judgment threshold, they are marked with an upward arrow ↑.

[0122] Table 1. Smooth tracking eye movement data and results for six subjects.

[0123]

[0124] Figure 2 shows the eye movement trajectories of Subject A. Figure 2(a) shows the eye movement trajectory of the left eye in the horizontal smooth following eye movement test, Figure 2(b) shows the eye movement trajectory of the right eye in the horizontal smooth following eye movement test, Figure 2(c) shows the eye movement trajectory of the left eye in the vertical smooth following eye movement test, and Figure 2(d) shows the eye movement trajectory of the right eye in the vertical smooth following eye movement test. From the various eye movement test data of Subject A in Table 1, it can be seen that the horizontal smooth following eye movement test data of both the left and right eyes is abnormal, and the eye movement trajectories of both eyes are consistent, indicating an abnormal result in the horizontal smooth following eye movement test. Similarly, the vertical smooth following eye movement test data of both the left and right eyes is abnormal, and the eye movement trajectories of both eyes are consistent, indicating an abnormal result in the vertical smooth following eye movement test. The final conclusion is that Subject A's smooth following eye movement test result is abnormal.

[0125] Figure 3 shows the eye movement trajectory diagrams of Subject B. Figure 3(a) shows the eye movement trajectory of the left eye in the horizontal smooth following eye movement test, Figure 3(b) shows the eye movement trajectory of the right eye in the horizontal smooth following eye movement test, Figure 3(c) shows the eye movement trajectory of the left eye in the vertical smooth following eye movement test, and Figure 3(d) shows the eye movement trajectory of the right eye in the vertical smooth following eye movement test. From the various eye movement test data of Subject B in Table 1, it can be seen that the horizontal smooth following eye movement test data of the left and right eyes are normal, indicating that the horizontal smooth following eye movement test results are normal; the vertical smooth following eye movement test data of the left and right eyes are abnormal, and the eye movement trajectories of the two eyes are inconsistent (C). vl ÷C vr <S2,F vl ÷F vr <S3, through on-site observation, it was found that the inconsistency in the eye movement trajectories of the two eyes was due to eyelid and eyelash obscuring the pupils in both eyes, thus the vertical smooth eye movement tracking test result was deemed invalid. The final judgment was that the smooth eye movement tracking test result for examinee B was invalid.

[0126] Figure 4 shows the eye movement trajectory diagrams of subject C. Figure 4(a) shows the eye movement trajectory of the left eye in the horizontal smooth following eye movement test, Figure 4(b) shows the eye movement trajectory of the right eye in the horizontal smooth following eye movement test, Figure 4(c) shows the eye movement trajectory of the left eye in the vertical smooth following eye movement test, and Figure 4(d) shows the eye movement trajectory of the right eye in the vertical smooth following eye movement test. From the various eye movement test data of subject C in Table 1, it can be seen that the horizontal smooth following eye movement test data of both the left and right eyes are normal, indicating that the horizontal smooth following eye movement test results are normal. The vertical smooth following eye movement test data of the left eye is normal, while the vertical smooth following eye movement test data of the right eye is abnormal (observation revealed that the abnormal data was caused by the right eyelashes obscuring the pupil), indicating that the vertical smooth following eye movement test results are normal. The final judgment is that subject C's smooth following eye movement test results are normal.

[0127] Figure 5 shows the eye movement trajectory diagrams of subject D. Figure 5(a) shows the eye movement trajectory of the left eye in the horizontal smooth following eye movement test, Figure 5(b) shows the eye movement trajectory of the right eye in the horizontal smooth following eye movement test, Figure 5(c) shows the eye movement trajectory of the left eye in the vertical smooth following eye movement test, and Figure 5(d) shows the eye movement trajectory of the right eye in the vertical smooth following eye movement test. From the various eye movement test data of subject D in Table 1, it can be seen that the horizontal smooth following eye movement test data of both the left and right eyes are normal, indicating that the horizontal smooth following eye movement test result is normal; the vertical smooth following eye movement test data of both the left and right eyes are normal, indicating that the vertical smooth following eye movement test result is normal. The final judgment is that subject D's smooth following eye movement test result is normal.

[0128] Figure 6 shows the eye movement trajectories of subject E. Figure 6(a) shows the eye movement trajectory of the left eye in the horizontal smooth following eye movement test, Figure 6(b) shows the eye movement trajectory of the right eye in the horizontal smooth following eye movement test, Figure 6(c) shows the eye movement trajectory of the left eye in the vertical smooth following eye movement test, and Figure 6(d) shows the eye movement trajectory of the right eye in the vertical smooth following eye movement test. From the various eye movement test data of subject E in Table 1, it can be seen that the horizontal smooth following eye movement test data of both eyes are normal, indicating a normal result for the horizontal smooth following eye movement test. The vertical smooth following eye movement test data of both eyes are abnormal, and the eye movement trajectories are consistent, indicating an abnormal result for the vertical smooth following eye movement test. The final judgment is that subject E's smooth following eye movement test result is abnormal.

[0129] Figure 7 shows the eye movement trajectories of subject Xu. Figure 7(a) shows the eye movement trajectory of the left eye in the horizontal smooth following eye movement test, Figure 7(b) shows the eye movement trajectory of the right eye in the horizontal smooth following eye movement test, Figure 7(c) shows the eye movement trajectory of the left eye in the vertical smooth following eye movement test, and Figure 7(d) shows the eye movement trajectory of the right eye in the vertical smooth following eye movement test. From the various eye movement test data of subject Xu in Table 1, it can be seen that the horizontal smooth following eye movement test data of both the left and right eyes are abnormal, and the eye movement trajectories of both eyes are consistent, indicating an abnormal result in the horizontal smooth following eye movement test. The vertical smooth following eye movement test data of both the left and right eyes are normal, indicating a normal result in the vertical smooth following eye movement test. The final judgment is that subject Xu's smooth following eye movement test result is abnormal.

[0130] In other embodiments, the target can be made to move smoothly and uniformly along a rectangular trajectory on the display for one or more cycles. Then, the eye movement data when the target moves horizontally and the eye movement data when it moves vertically are statistically analyzed, and the smooth following eye movement result judgment module makes the corresponding judgment.

[0131] In other embodiments, the speed at which the target moves smoothly in the horizontal or vertical direction can also vary with time according to a sine function. For example, taking the horizontal direction as an example, the target's moving speed v is set to a function of time t, v(t) = Asin(ωt), with the center of the display screen as the origin, rightward as the positive direction, and the target's initial position as -A / ω (degrees), and then it begins to move to the right; the target moves fastest at the midpoint, with a speed of A; when the target moves to the right at A / ω (degrees), the speed becomes 0 and it begins to move to the left; the period of the target's movement is 2π / ω (seconds). The number of periods of target movement, the speed of movement, the range of movement, and the starting and ending points of movement can be set.

[0132] In addition, during eye movement testing, if the duration is long, the subject may blink once or several times during the test. This embodiment also includes an automatic blink filtering module, a program running on a computer that can filter out abnormal eye movement data during blinks. This avoids misjudging blinks as rapid eye movements and also avoids calculation errors in the average tracking deviation caused by eye movement point coordinate deviations due to blinks.

[0133] Example 2

[0134] Using this eye-tracking device, eye-tracking examinations were conducted on hundreds of patients with depressive disorders in multiple hospitals. It was found that over 80% of these patients had abnormal smooth tracking eye-tracking results, while such abnormalities are relatively rare in healthy individuals. This indicates a strong correlation between depressive disorders and abnormal smooth tracking eye-tracking results, suggesting that smooth tracking eye-tracking can be used for screening or auxiliary diagnosis of depressive disorders.

[0135] The eye-tracking examination device in this embodiment also includes an auxiliary diagnostic module, which is a program running on a computer. If the smooth eye-tracking result judgment module determines that the subject's smooth eye-tracking result is abnormal, the auxiliary diagnostic module determines that the subject has a high risk of having a depressive disorder; if the smooth eye-tracking result judgment module determines that the subject's smooth eye-tracking result is normal, the auxiliary diagnostic module determines that the subject has a low risk of having a depressive disorder. The auxiliary diagnostic results of this device can provide a reference for the formal diagnosis by professional physicians; it can also be used for rapid screening in schools, communities, physical examinations, etc., and then the high-risk individuals identified in the screening can be further diagnosed by professional physicians, thereby improving the efficiency of depressive disorder screening.

[0136] Furthermore, the eye movement testing device used in this embodiment, based on Embodiment 1, also includes a fixation module and a saccade module, enabling it to perform fixation eye movement testing and saccade eye movement testing. Through fixation eye movement testing and saccade eye movement testing on multiple patients with depressive disorders, it was found that the abnormal rates of both fixation and saccade eye movement testing in these patients were significantly higher than those in healthy individuals.

[0137] The fixation module is a program running on a computer. Its function is to display a fixed optotype at a designated location on the monitor after the fixation eye movement test begins, instruct the subject to stare at it, and then record the coordinates of the left and right eye movement points during the fixation eye movement test. In this embodiment, during the fixation eye movement test, a white dot with a diameter of 1° is displayed at the center of the monitor for 10 seconds.

[0138] The saccade module is a program running on a computer. Its function is to randomly display a moving target at different positions on the monitor after the saccade eye movement test begins. The subject is required to move their eyes to the corresponding position as the target moves. In this embodiment, during the saccade eye movement test, a white dot with a diameter of 1° is first displayed at the center of the monitor. After staying at the center for 1 second, it randomly moves up, down, left, or right to a position 10° away from the center, holds for 1 second, and then jumps back to the center. This process is repeated 10 times over a total of 20 seconds.

[0139] By observing and analyzing the results of fixation eye movement tests in patients with depressive disorders, a common abnormality was found to be square wave saccades. Square wave saccades refer to horizontal eye movements that sag away from the fixation point. The fixation module can detect the number of square wave saccades. In this embodiment, the method for detecting square wave saccades using the fixation module is as follows: the left eye's eye movement point saccades horizontally (peak eye velocity > 100° / second) away from the midpoint and then saccades back to the midpoint (peak eye velocity > 100° / second), with a deviation time > 300ms and a deviation amplitude > 1°, and this is recorded as one square wave saccade. Similarly, the number of square wave saccades for the right eye can be recorded. A threshold S4 is set; if the number of square wave saccades per unit time for both the left and right eyes is ≥ S4, it is determined that a square wave saccade abnormality exists during the fixation eye movement test. In this embodiment, S4=2 is set. If the number of square wave jumps in the left eye is ≥2 times per 10 seconds, and the number of square wave jumps in the right eye is ≥2 times per 10 seconds, it is judged that there is an abnormality of square wave jumps during fixation eye movement examination.

[0140] Figure 8 This is an eye movement trajectory diagram of a healthy person's fixation eye movement test. The horizontal axis represents time, and the vertical axis represents the horizontal component of the eye movement point coordinates. Since the eye movement trajectories of both eyes are similar, to save space, only the eye movement trajectory diagram of the left eye is presented. Based on the above judgment method, the fixation module judged that the number of square wave jumps in the left and right eyes of this subject was 0, and judged that there was no abnormal fixation square wave jump during the fixation eye movement test.

[0141] Figure 9 This is an eye movement trajectory diagram of a patient with a depressive disorder during a fixation eye movement test. Because the eye movement trajectories of both eyes are similar, only the eye movement trajectory diagram of the left eye is presented to save space. Based on the above judgment method, the fixation module judged that the number of square wave jumps in the left and right eyes of this subject was 3, which was judged as an abnormality of square wave jumps during the fixation eye movement test.

[0142] By observing and analyzing the results of saccade eye movement tests in patients with depressive disorders, a common abnormality was found to be visual distance malfunction. Visual distance malfunction refers to a situation where, after a target point jumps to a new position, the eye movement point significantly exceeds or lags behind the target point's position when the eye performs a saccade to view the new location. The number of visual distance malfunctions can be detected using a saccade module. In this embodiment, the method for detecting visual distance malfunction using the saccade module is as follows: after the target point jumps from the midpoint upwards, downwards, leftwards, or rightwards to a new position, the distance traveled by the left eye movement point during the first saccade (the distance between the starting and ending saccades) is recorded. If the first saccade distance of the left eye movement point is less than 70% of the target point's movement distance (called undershoot) or greater than 115% (called overshoot), it is determined that a visual distance malfunction has occurred in the left eye. Similarly, the number of visual distance malfunctions in the right eye can be recorded. A threshold S5 is set. If the ratio of the number of times the visual distance is poor in the left eye divided by the total number of target jumps is greater than or equal to S5, and the ratio of the number of times the visual distance is poor in the right eye divided by the total number of target jumps is also greater than or equal to S5, it is determined that there is an abnormality in visual distance during saccade eye movement. In this embodiment, S5 is set to 20%. If, in every 10 target point jumps, the number of times the visual distance is poor in the left eye is greater than or equal to 2, and the number of times the visual distance is poor in the right eye is also greater than or equal to 2, it is determined that there is an abnormality in visual distance during saccade eye movement.

[0143] Figure 10 shows the eye movement trajectory of a healthy person during a saccade eye movement test. The horizontal axis represents time. In Figure 10(a), the vertical axis represents the horizontal component of the eye movement point coordinates, and in Figure 10(b), the vertical axis represents the vertical component of the eye movement point coordinates. Since the eye movement trajectories of both eyes are similar, only the eye movement trajectory of the left eye is shown to save space. To facilitate comparison of the difference between the eye movement point coordinates and the optotype coordinates at different times, the optotype trajectory is also displayed at the same time. The optotype trajectory is a gray square wave in the figure. Based on the above judgment method, the saccade module judged that the number of visual distance impairments in the left and right eyes of this subject was 0, and judged that there was no visual distance impairment abnormality during the saccade eye movement test.

[0144] Figure 11 shows the eye movement trajectory of a patient with depressive disorder during a saccade eye movement test. The horizontal axis represents time. In Figure 11(a), the vertical axis represents the horizontal component of the eye movement point coordinates, and in Figure 11(b), the vertical axis represents the vertical component of the eye movement point coordinates. Since the eye movement trajectories of both eyes are similar, only the eye movement trajectory of the left eye is shown to save space. To facilitate comparison of the differences between the eye movement point coordinates and the optotype coordinates at different times, the optotype trajectory is also displayed at the same time. The optotype trajectory is a gray square wave in the figure. Based on the above judgment method, the saccade module judged that there were 6 instances of visual distance malfunction in both the left and right eyes of this subject (3 instances of overshoot in the horizontal direction and 3 instances of undershoot in the vertical direction), and judged that there was an abnormality of visual distance malfunction during the saccade eye movement test.

[0145] In this embodiment, the eye-tracking device was used to perform horizontal smooth tracking eye-tracking, vertical smooth tracking eye-tracking, fixation eye-tracking, and saccade eye-tracking tests on 102 patients with depressive disorders and 56 healthy individuals. The abnormality rates of each eye-tracking test were also calculated, and the results are shown in Table 2.

[0146] Table 2 Abnormal rates for various eye movement examinations

[0147]

[0148] The abnormality rates for horizontal smooth eye-tracking tests in the patient group were calculated as follows: horizontal smooth eye-tracking test abnormality rate (number of patients with abnormal results divided by the total number of patients); vertical smooth eye-tracking test abnormality rate (number of patients with abnormal results divided by the total number of patients); smooth eye-tracking test abnormality rate (number of patients with abnormal results in either horizontal or vertical smooth eye-tracking tests divided by the total number of patients); fixation eye-tracking test square wave jump abnormality rate (number of patients with square wave jump abnormalities during fixation eye-tracking tests divided by the total number of patients); and saccade eye-tracking test visual distance impairment abnormality rate (number of patients with visual distance impairment during saccade eye-tracking tests divided by the total number of patients). The abnormality rates in the healthy group were calculated similarly to those in the patient group.

[0149] As shown in Table 2, the abnormality rate of smooth tracking eye movement (SLT) results reached 82.35% in patients with depressive disorders. Therefore, abnormal SLT results can be used as a primary indicator for screening or auxiliary diagnosis of depressive disorders. Furthermore, because the abnormality rates of square wave jumps in fixation eye movement (SLT) and visual distance impairment in saccade eye movement (SAE) were significantly higher in the depressive disorder group than in the healthy group, these abnormalities can be used as reference indicators for screening or auxiliary diagnosis of depressive disorders. Combining these four eye movement tests allows for a comprehensive assessment of the risk level of the examinee having a depressive disorder.

[0150] This embodiment also includes a risk level assessment module, which is a program running on a computer. The specific method for its assessment is as follows:

[0151] Level I risk: One of the horizontal smooth eye movement test results and the other of the vertical smooth eye movement test results is abnormal and normal; there is no square wave jump abnormality in fixation eye movement test and no visual distance abnormality in saccade eye movement test.

[0152] Level II risk: Two of the following four items are present: abnormal results in horizontal smooth eye movement test, abnormal results in vertical smooth eye movement test, abnormal square wave jump in fixation eye movement test, and abnormal visual distance in saccade eye movement test. In addition, at least one of the two items, abnormal results in horizontal smooth eye movement test and abnormal results in vertical smooth eye movement test, is present.

[0153] Level III risk: Three out of the following four items are present: abnormal results of horizontal smooth eye movement test, abnormal results of vertical smooth eye movement test, abnormal square wave jump in fixation eye movement test, and abnormal visual distance in saccade eye movement test.

[0154] Level IV risk: All four of the following are present: abnormal results in horizontal smooth eye movement test, abnormal results in vertical smooth eye movement test, abnormal square wave jump in fixation eye movement test, and abnormal visual distance in saccade eye movement test. The higher the risk level, the higher the risk of the examinee having a depressive disorder.

Claims

1. An eye examination apparatus, characterized in that The application comprises the following modules: a display module capable of displaying two modes, defined as mode one and mode two respectively, wherein: mode one is horizontal smooth pursuit eye movement examination, the display module displays a target moving smoothly in the horizontal direction, the trajectory of the target is controlled by the program, and the position of the target at each moment is known; mode two is vertical smooth pursuit eye movement examination, the display module displays a target moving smoothly in the vertical direction, the trajectory of the target is controlled by the program, and the position of the target at each moment is known; when the target moves, the eyes of the examinee follow the movement of the target; in the horizontal smooth pursuit eye movement examination or the vertical smooth pursuit eye movement examination, the left eye and the right eye can simultaneously see the target; a near-infrared image shooting module comprising at least one near-infrared camera and at least one near-infrared light source, capable of simultaneously shooting left eye images and right eye images; a calibration module for calibrating the left eye and the right eye, obtaining a left eye calibration function through left eye calibration, and obtaining a right eye calibration function through right eye calibration; an eye movement point calculation module for calculating left eye eye movement point coordinates according to the left eye images and the left eye calibration function, and calculating right eye eye movement point coordinates according to the right eye images and the right eye calibration function after the left eye calibration and the right eye calibration are completed; a smooth pursuit eye movement examination result judgment module for recording left eye eye movement point coordinate data and right eye eye movement point coordinate data, and then judging whether the smooth pursuit eye movement examination result of the examinee is normal or abnormal: in the horizontal smooth pursuit eye movement examination, the recorded left eye eye movement point coordinate data is left eye horizontal smooth pursuit eye movement examination data, and the recorded right eye eye movement point coordinate data is right eye horizontal smooth pursuit eye movement examination data; in the vertical smooth pursuit eye movement examination, the recorded left eye eye movement point coordinate data is left eye vertical smooth pursuit eye movement examination data, and the recorded right eye eye movement point coordinate data is right eye vertical smooth pursuit eye movement examination data; if the left eye horizontal smooth pursuit eye movement examination data of the examinee is abnormal, the right eye horizontal smooth pursuit eye movement examination data of the examinee is abnormal, and the eye movement trajectories of the two eyes are consistent, it is judged that the horizontal smooth pursuit eye movement examination result of the examinee is abnormal; if the left eye horizontal smooth pursuit eye movement examination data is normal and / or the right eye horizontal smooth pursuit eye movement examination data is normal, it is judged that the horizontal smooth pursuit eye movement examination result of the examinee is normal; if the left eye vertical smooth pursuit eye movement examination data of the examinee is abnormal, the right eye vertical smooth pursuit eye movement examination data of the examinee is abnormal, and the eye movement trajectories of the two eyes are consistent, it is judged that the vertical smooth pursuit eye movement examination result of the examinee is abnormal; if the left eye vertical smooth pursuit eye movement examination data is normal and / or the right eye vertical smooth pursuit eye movement examination data is normal, it is judged that the vertical smooth pursuit eye movement examination result of the examinee is normal; if the horizontal smooth pursuit eye movement examination result of the examinee is abnormal or the vertical smooth pursuit eye movement examination result of the examinee is abnormal, it is judged that the smooth pursuit eye movement examination result of the examinee is abnormal; if the horizontal smooth pursuit eye movement examination result of the examinee is normal and the vertical smooth pursuit eye movement examination result of the examinee is normal, it is judged that the smooth pursuit eye movement examination result of the examinee is normal.

2. The eye examination apparatus of claim 1, wherein In the smooth pursuit eye movement examination result judgment module, the judgment threshold PZ1, PC1, PF1 of the horizontal smooth pursuit eye movement examination is set; the judgment threshold PZ2, PC2, PF2 of the vertical smooth pursuit eye movement examination is set; The method for judging whether the left eye horizontal smooth pursuit eye movement examination data is normal or abnormal is: the smooth pursuit eye movement examination result judgment module calculates the left eye average pursuit deviation Z hl , the total number of left eye rapid eye movement C hl , and the total amplitude of left eye rapid eye movement F hl When Z hl >PZ1, or C hl >PC1, or F hl >PF1, it is judged that the left eye horizontal smooth pursuit eye movement examination data is abnormal; when Z hl ≤PZ1, and C hl ≤PC1, and F hl ≤PF1, it is judged that the left eye horizontal smooth pursuit eye movement examination data is normal. The method for judging whether the right eye horizontal smooth pursuit eye movement examination data is normal or abnormal is: the right eye horizontal smooth pursuit eye movement examination result judgment module calculates the right eye average pursuit deviation Z hr , the total number of right eye rapid eye movement C hr , and the total amplitude of right eye rapid eye movement F hr When Z hr >PZ1, or C hr >PC1, or F hr >PF1, it is judged that the right eye horizontal smooth pursuit eye movement examination data is abnormal; when Z hr ≤PZ1, and C hr ≤PC1, and F hr ≤PF1, it is judged that the right eye horizontal smooth pursuit eye movement examination data is normal. The method for judging whether the vertical smooth pursuit eye movement test data of the left eye is normal or abnormal is: the smooth pursuit eye movement test result judgment module calculates the average pursuit deviation Z of the left eye during the vertical smooth pursuit eye movement test vl , the total number of rapid eye movement C of the left eye vl , the total amplitude F of rapid eye movement of the left eye vl When Z vl >PZ2, or C vl >PC2, or F vl >PF2, it is judged that the vertical smooth pursuit eye movement test data of the left eye is abnormal. When Z vl ≤ PZ2, and C vl ≤ PC2, and F vl ≤ PF2, it is determined that the left eye vertical smooth pursuit eye movement test data is normal. The method for judging whether the vertical smooth pursuit eye movement examination data of the right eye is normal or abnormal is: the smooth pursuit eye movement examination result judgment module calculates the average pursuit deviation Z of the right eye during the vertical smooth pursuit eye movement examination vr , the total number of rapid eye movement C of the right eye vr , the total amplitude F of rapid eye movement of the right eye vr When Z vr >PZ2, or C vr >PC2, or F vr >PF2, it is judged that the vertical smooth pursuit eye movement examination data of the right eye is abnormal; when Z vr ≤PZ2, and C vr ≤PC2, and F vr ≤PF2, it is judged that the vertical smooth pursuit eye movement examination data of the right eye is normal.

3. The eye examination apparatus of claim 2, wherein, PZ2>PZ1, and PC2>PC1, and PF2>PF1.

4. The eye examination apparatus of claim 2, wherein, In the smooth pursuit eye movement examination result judgment module, the method for judging the inconsistency of the eye movement trajectories of the two eyes is any one of the following methods: Method one: a distance threshold S1 is set, if the average distance of the eye movement point coordinates of the two eyes during the horizontal smooth pursuit eye movement examination or the vertical smooth pursuit eye movement examination is greater than S1, it is judged that the eye movement trajectories of the two eyes are inconsistent; Method two: set a proportion threshold S2, if the proportion of the smaller value divided by the larger value in C hl and C hr of horizontal smooth pursuit eye movement test is < S2, it is judged that the eye movement trajectories of the two eyes are inconsistent; if the proportion of the smaller value divided by the larger value in C vl and C vr of vertical smooth pursuit eye movement test is < S2, it is judged that the eye movement trajectories of the two eyes are inconsistent; Method three: set a proportion threshold S3, if the proportion of the smaller value divided by the larger value in F hl and F hr during horizontal smooth pursuit eye movement test is < S3, it is judged that the eye movement trajectories of the two eyes are inconsistent; if the proportion of the smaller value divided by the larger value in F vl and F vr during vertical smooth pursuit eye movement test is < S3, it is judged that the eye movement trajectories of the two eyes are inconsistent.

5. The eye examination apparatus of claim 4, wherein, In the smooth pursuit eye movement examination result judgment module, 0.5°≤S1≤1.5°, 70%≤S2≤90%, and 70%≤S3≤90%.

6. The eye-tracking device according to any one of claims 1 to 5, characterized in that It also includes an auxiliary diagnosis module, if the smooth pursuit eye movement examination result judgment module judges that the smooth pursuit eye movement examination result of the examinee is abnormal, the auxiliary diagnosis module judges that the examinee has a higher risk of having a depressive disorder; if the smooth pursuit eye movement examination result judgment module judges that the smooth pursuit eye movement examination result of the examinee is normal, the auxiliary diagnosis module judges that the examinee has a lower risk of having a depressive disorder.

7. The eye examination apparatus of claim 6, wherein It also includes a fixation module and a saccade module; the fixation module calculates the number of times of square wave saccades of the left eye and the right eye during the fixation eye movement examination, sets a number threshold S4, if the number of times of square wave saccades of the left eye per unit time is greater than or equal to S4, and the number of times of square wave saccades of the right eye per unit time is greater than or equal to S4, it is judged that there is an abnormal square wave saccade during the fixation eye movement examination; The saccade module calculates the number of times of poor visual resolution of the left eye and the right eye during the saccade eye movement examination, sets a proportion threshold S5, if the proportion of the number of times of poor visual resolution of the left eye to the total number of times of target jumping is greater than or equal to S5, and the proportion of the number of times of poor visual resolution of the right eye to the total number of times of target jumping is greater than or equal to S5, it is judged that there is an abnormal poor visual resolution during the saccade eye movement examination.

8. The eye examination apparatus of claim 7, wherein, In the fixation module, the number threshold S4 is set to 2, if the number of times of square wave saccades of the left eye per 10 seconds is greater than or equal to 2, and the number of times of square wave saccades of the right eye per 10 seconds is greater than or equal to 2, it is judged that there is an abnormal square wave saccade during the fixation eye movement examination; in the saccade module, the proportion threshold S5 is set to 20%, if the proportion of the number of times of poor visual resolution of the left eye to the total number of times of target jumping is greater than or equal to 20%, and the proportion of the number of times of poor visual resolution of the right eye to the total number of times of target jumping is greater than or equal to 20%, it is judged that there is an abnormal poor visual resolution during the saccade eye movement examination.

9. The eye examination apparatus of claim 7, wherein, It also includes a risk level judgment module, which judges the risk level of the examinee having a depressive disorder, the method being: Level I risk: one of the horizontal smooth pursuit eye movement examination result and the vertical smooth pursuit eye movement examination result is abnormal, and one is normal; there is no abnormal square wave saccade during the fixation eye movement examination, and there is no abnormal poor visual resolution during the saccade eye movement examination; Level Ⅱ risk: two of the following four items exist: horizontal smooth pursuit eye movement test result abnormality, vertical smooth pursuit eye movement test result abnormality, fixation eye movement test square wave jump abnormality, saccade eye movement test poor visual acuity abnormality, and at least one of the horizontal smooth pursuit eye movement test result abnormality and the vertical smooth pursuit eye movement test result abnormality exists; Level Ⅲ risk: three of the following four items exist: horizontal smooth pursuit eye movement test result abnormality, vertical smooth pursuit eye movement test result abnormality, fixation eye movement test square wave jump abnormality, saccade eye movement test poor visual acuity abnormality; Level Ⅳ risk: all of the following four items exist: horizontal smooth pursuit eye movement test result abnormality, vertical smooth pursuit eye movement test result abnormality, fixation eye movement test square wave jump abnormality, saccade eye movement test poor visual acuity abnormality; The higher the risk level is, the higher the risk of judging that the subject has a depressive disorder is.

10. The eye examination apparatus of claim 1, wherein, A head fixing support is further included to fix the head of the subject when the eye movement test is performed.

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