RU2752031C1 - Method for predicting the risk of primary open-angle glaucoma - Google Patents

Abstract

FIELD: medicine, ophthalmology in particular.

SUBSTANCE: invention relates to medicine, namely to ophthalmology. The current level of intraocular pressure, age, the indicator of optical coherence tomography with angiography - the density of the vascular pattern at the level of the layer of retinal nerve fibers peripapillary are determined, the presence of heredity burdened by glaucoma is noted. After that, the obtained anamnestic data and the results of the examination are substituted into a mathematical model: PRR POAG=5.679*HEREDITY-0.087*RPC_DENSITY+1.677*IOP-0.137*AGE-19.823, where: PRR POAG is the glaucoma risk factor; HEREDITY the presence of glaucoma-burdened heredity, in case of presence 1, in case of absence 0; RPC_DENSITY the density of the vascular pattern at the level of the retinal nerve fiber layer peripapillary,%; IOP the current level of intraocular pressure, mmHg; AGE age, years; 19.823 a mathematical constant. With a risk factor of more than 0.5, a high risk of primary open-angle glaucoma (POAG) is predicted.

EFFECT: method allows predicting the risk of developing glaucoma with high sensitivity and specificity, as well as expanding the arsenal of POAG diagnostic tools.

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Description

The invention relates to medicine, namely ophthalmology, and can be used to predict the risk of developing glaucoma.

Currently, most researchers believe that the main diagnostic feature of this heterogeneous group of diseases is specific glaucomatous optic neuropathy (GON), with corresponding visual field disorders [National Guide to Glaucoma: for practitioners / ed. E.A. Egorova, V.P. Yericheva. - 4th ed., Rev. and additional - Moscow: GEOTAR-Media, 2019 .-- 384 p. DOI: 10.33029 / 9704-5442-8-GLA-2020-1-384].

Primary open-angle glaucoma (POAG), as the most common form of glaucoma, belongs to a group of diseases with a hereditary predisposition associated with age, arising and developing under the interaction of heredity and the environment [Yerichev VP, Yegorov EA On the pathogenesis of primary open-angle glaucoma // Bulletin of Ophthalmology. - 2014. - No. 6. - S. 98-104].

Along with a violation of the outflow of intraocular fluid and an increase in the level of intraocular pressure (IOP), it highlights the vascular factor as one of the reasons for the development and progression of POAG [Astakhov Yu.S., Akopov EL, Nefedova D.M. Vascular risk factors for the development of primary open-angle glaucoma // Russian medical journal. Clinical Ophthalmology - 2008. - No. 2. - S. 68].

A number of authors substantiate the role of the vascular factor in the development and progression of POAG due to impaired vascular autoregulation, as well as a persistent decrease in systemic arterial and perfusion pressure in the glaucomatous eye [Kurysheva N.I. Ocular hemoperfusion and glaucoma / N.I. Kuryshev. - M: Greenlight, 2014. - 128 p.].

In addition to high IOP, the following were noted as significant risk factors for the development and progression of POAG: old age, family history of glaucoma, age, black race, use of systemic or local corticosteroids, concomitant somatic diseases and others [Weinreb RN, Aung T., Medeiros FA The pathophysiology and treatment of glaucoma: a review. JAMA. 2014; 311 (18): 1901-1911.doi: 10.1001 / jama.2014.3192.].

In connection with the multifactorial nature of the pathogenesis of POAG, methods have been developed and continue to be developed for predicting the risk of developing POAG in order to prevent blindness and low vision due to this disease. It is of interest to isolate POAG biomarkers that allow predicting the likelihood of developing POAG and the nature of its course.

РМ,

Р, Brasnu E, Baudouin С,

A. Optic Disc Vascularization in Glaucoma: Value of Spectral-Domain Optical Coherence Tomography Angiography. J Ophthalmol. 2016;2016:6956717. doi: 10.1155/2016/6956717].According to the literature, the indicators of optic disc microcirculation, studied using optical coherence tomography with angiography (OCTA), are reliable markers indicating the risk of developing glaucoma in patients with suspected POAG, and are also associated with corresponding functional and structural defects during the development of the disease ( Chen CL, Zhang A, Bojikian KD, Wen JC, Zhang Q, Xin C, Mudumbai RC, Johnstone MA, Chen PP, Wang RK. Peripapillary Retinal Nerve Fiber Layer Vascular Microcirculation in Glaucoma Using Optical Coherence Tomography-Based Microangiography Invest. Vis Ophthalmol Sci. 2016 Jul 1; 57 (9): OCT475-85.doi: 10.1167 / iovs.l5-18909). There was a significant correlation between the density of the optic nerve disc vessels and the indicators of optical coherence tomography (OCT): the neuroretinal belt, the thickness of the layer of nerve fibers, the thickness of the layer of ganglion cells, as well as the perimetric indicator of the mean deviation [

RM,

P, Brasnu E, Baudouin C,

A. Optic Disc Vascularization in Glaucoma: Value of Spectral-Domain Optical Coherence Tomography Angiography. J Ophthalmol. 2016; 2016: 6956717. doi: 10.1155 / 2016/6956717].

Known methods for predicting the risk of development and progression of glaucoma with the determination of clinical and laboratory parameters: the concentration of MMP-9 and TIMP-1 of the tear fluid by enzyme immunoassay [Patent RU 2665005, 2018.], the level of lactate in the blood on a biochemical automatic analyzer [Patent RU 2530588 , 2013], the level of tear protein by the method of crystallography [Patent RU No. 2281023, 2006], the total and effective concentration of albumin in the tear by the method of fluorimetry with the calculation of the ECA / OKA ratio [Patent RU No. 2235503, 2003]. The disadvantages of these clinical and laboratory methods are: the complexity or inaccessibility of diagnostics, reagents, special, possibly expensive equipment, the involvement of trained medical personnel conducting the study, the need to collect tears in an amount sufficient for research, which is difficult in patients with glaucoma due to the frequent development of the "syndrome dry eye ”, as well as the lack of consideration of other risk factors for the development and prediction of POAG development, except for laboratory ones.

Known methods for predicting the risk of development and progression of GON on the basis of bidirectional pneumoplanning tonometry with an assessment of the biomechanical parameters of the fibrous membrane of the eye and the calculation of the coefficient of biomechanical stress of the fibrous membrane of the eye according to the formula: Kbs = IOPg / CH + CRF [Patent RU No. 2610565,2017]; corneal hysteresis (CG) and central corneal thickness (CTR) with the calculation of the biomechanical coefficient of the cornea: K = CG / CTR [Patent RU No. 2354287, 2009]; as well as evaluating the elastic properties of the cornea and sclera of the eye in differential tonometry according to Shiotz (γS) and in elastotonometry according to Maklakov (γM) with the determination of the coefficient of elasto-rise according to the formula K = γS / γM [Patent RU No. 2599208, 2016]. These models are based on indicators associated with measuring the IOP level and assessing the biomechanical properties of the corneoscleral membrane, however, the vascular and other factors of the pathogenesis of GON were not taken into account.

A known method for predicting the risk of development and progression of glaucoma with the determination of a set of indicators: the speed of propagation of the pulse wave (PWV) in the arteries of the upper and lower extremities using sphygmomanometry, flow-dependent vasodilation (PZVD) of the brachial artery in a sample with reactive hyperemia, total antioxidant capacity of blood serum (AOS), the level of severity of depression (Ud) [Patent RU No. 2669735, 2018]. Calculate the value of regression F using the mathematical formula: F = 0.152 + 1.053 × PWV_worse-2.007 × PWVD-0.075 × AOS + 0.891 × UD, and then the risk coefficient of glaucoma progression Kp: Kp = 1 / (1 + e (-F) ), with Kp≤0.5 a low is predicted, with a Kp value> 0.5 - a high risk of glaucoma progression. The disadvantage of this model is the need for a whole range of additional research methods (sphygmomanometry, electrocardiography, phonocardiography, ultrasound examination, as well as determination of the antioxidant capacity of blood serum), which are available only in specially equipped offices and laboratories, and are also laborious for an ophthalmologist to carry out. Carrying out the above studies, along with the patient passing a survey to identify the level of depression severity according to the A.T. Beck, takes a significant amount of time.

A known method for predicting the progression of optic neuropathy in primary open-angle glaucoma [Patent RU No. 2706956, 2019]. The method is based on determining the thickness of the inner layers of the macula in the lower hemisphere, the relative density of the vessels of the surface layer in the parafovea using the OCTA method, the pattern-ERG coefficient - PERG Ratio 2 - the ratio of the latency of stationary PERG to stimuli with angular sizes of 0.8 ° and 16 °. When the thickness of the inner parts of the macula is less than 105 microns, the relative density of the vessels of the surface layer in the parafovea is less than 45%, the value of PERG Ratio 2≤1.12 predicts the progression of GON in POAG. This method, due to the combination of certain OCTA and EPI data, has a high accuracy in predicting the progression of GON (100% sensitivity and 90% specificity). In this method, the main attention is paid to calculating the risk of POAG progression, without affecting the risk of developing the disease.

There is a known method for predicting the development of open-angle glaucoma in patients with ocular manifestations of pseudoexfoliative syndrome (PES), characterized by the fact that they determine the stage of PES in the eye, measure the thickness of the lens, note the patient's age and the presence or absence of atherosclerosis, coronary heart disease, chronic cerebrovascular insufficiency, hypertension, after which the risk index of development (IRR) of open-angle glaucoma is calculated according to the formula: IRR = 0.0035 * RRP + 0.173 * AED + 0.094 * HR + 0.528 * AT + 0.377 * IHD + 0.276 * HNSGM + 0.388 * GB-0.322 , where: ROS - patient's age, years, PES - stage of PES from 1 to 3, ХР - lens thickness in mm; presence - 1, absence - 0 concomitant cardiovascular diseases: AT - atherosclerosis, coronary artery disease - ischemic heart disease, CHSGM - chronic cerebrovascular insufficiency, hypertension - hypertension, 0.322 - an independent constant; and if the IRR value> 2, then the development of open-angle glaucoma in the eyes with manifestations of RPE is predicted [patent RU 2508043, 2014]. The disadvantages of this method are the attachment of the prognosis to a certain form of glaucoma (pseudoexfoliative) and its laboriousness.

The closest analogue of the invention is a method for predicting the risk of development and progression of POAG, which consists in determining heredity for glaucoma, the minimum daily IOP, daily IOP fluctuation, the concentration of matrix metalloproteinases (MMP-9) in the tear fluid by the method of enzyme-linked immunosorbent assay, after which calculate the risk of developing the disease by the mathematical formula: Probability of developing glaucoma = -1.531 + 0.159 heredity + 0.0047 MMP-9 (in ng / ml) + 0.067 minimum daily IOP (in mm Hg) + 0.052 daily IOP fluctuation [ Levanova O.N., Likhvantseva V.G., Sokolov V.A., Borisenko T.E. Possibilities of modern statistical methods of regression analysis in the prognosis of primary open-angle glaucoma // Practical Medicine. - 2018. - Volume 16. - No. 5. - S. 35-40]. The disadvantages of the prototype are: the need for special, possibly expensive equipment, the involvement of trained medical personnel conducting the study, the need to collect tears in a volume sufficient for the study, which is difficult in patients with glaucoma due to the frequent development of "dry eye syndrome", the need for multiple IOP measurements.

The objective of the invention is to develop a method for predicting the risk of developing glaucoma with high sensitivity and specificity, expanding the arsenal of methods for diagnosing POAG.

The technical result when using the invention is to simplify the method.

The proposed method for predicting the risk of developing glaucoma is as follows. In a patient with a suspicion of this disease, the current IOP level, age, OCTA index - the density of the vascular pattern at the level of the retinal nerve fiber layer are determined peripapillary, the presence of heredity burdened by glaucoma is noted. After that, the obtained anamnestic data and examination results are substituted into the mathematical model:

PRR POAG = 5.679 * HEREDITY-0.087 * RPC_DENSITY + 1.677 * IOP-0.137 * AGE-19.823,

where:

PRR POAG - coefficient of risk of developing glaucoma;

HEREDITY - the presence of heredity burdened by glaucoma, if present - 1, in the absence - 0;

RPC_DENSITY — density of the vascular pattern at the level of the layer of nerve fibers of the retina, peripapillary,%;

IOP - current level of intraocular pressure, mm Hg;

AGE - age, years;

19.823 is a mathematical constant.

If the value of the risk coefficient for developing glaucoma is more than 0.5, a high risk of developing POAG is predicted.

The invention is illustrated by the following figures: FIG. 1 shows a logit model of regression analysis indicating significant risk factors for POAG; in fig. 2 - parameters of linear regression of POAG development.

In order to develop a model for predicting the risk of POAG development, we analyzed the data of 348 patients (348 eyes) with initial and advanced stages of the disease aged 45 to 87 (on average 61.28 ± 10.13) years. Of these, 257 (73.85%) are women and 91 (26.15%) are men. The criterion for inclusion in the study was the diagnosis "Primary open-angle glaucoma" (H40.1), established on the basis of clinical, laboratory and instrumental research methods in accordance with modern diagnostic criteria (Federal Clinical Guidelines for Ophthalmology, approved by the Ministry of Health of Russia, 2017), and also the age of patients over 45 years old. The control group consisted of 48 individuals (48 eyes) without glaucoma, comparable to POAG patients in terms of gender and age.

When developing the model, along with traditional clinical methods for diagnosing glaucoma (visometry, ophthalmoscopy), we used non-contact tonometry (Nidek, Japan). OCTA DZN (Optovue Avanti RTVue XR, USA) was carried out on an area of 4.5 × 4.5 mm in the AngioDisc mode. The levels of segmentation of the optic disc choroid plexus were automatically identified in accordance with the standard research protocol, incl. ONH (optic nerve head, full layer), RPC (radial peripapillary capillaries, layer of plexus of nerve fibers). The blood flow index, the density of the vascular pattern of the optic disc were determined automatically.

Observation of patients was carried out on the basis of the presence / absence of determination of signs characterizing GON. Dividing the outcomes into two possible ones (binary sign): the development of the disease and its absence, we used binary logistic regression to make a forecast.

As a result of statistical analysis, a logit model was obtained that most accurately represents the available regression. It was found that the following indicators were significantly associated with the disease: baseline IOP / (IOP), the presence of glaucoma in relatives / HEREDITY, age / AGE, density of the vascular pattern at the level of the peripapillary layer of retinal nerve fibers RPC_DENSITY (Fig. 1).

The final explanatory power of the regression model was R-square 0.88. Referring to this indicator of the quality of fit (McFadden's CD), it can be concluded that the regression equation explains 88% of the variation in the dependent variable "presence of glaucoma" based on identifying individual patient indicators.

The compliance of the presented model with real data was verified using the Hosmer-Lemeshov test (Fig. 2). As a result of the test, a point estimate of the parameters of interest to us was obtained, and their interval estimates were calculated.

Thus, the estimated linear regression logit model can be represented as: PRR POAG = 5.679 * HEREDITY-0.087 * RPC_DENSITY + 1.677 * IOP-0.137 * AGE-19.823

This formula can be used to calculate the risk of developing POAG in patients with suspected glaucoma. To do this, the numerical value of the IOP level (mm Hg), age (years), and capillary density at the RPC level (%) are substituted into the formula. If the patient has heredity for glaucoma, 1 is substituted into the formula, in the absence - 0. Then the risk coefficient for the development of glaucoma is calculated. The development of POAG is predicted when the value of the indicator is more than 0.5.

The sensitivity of the model was 97.92; specificity - 95.69 The predictive assessment of the POAG development model was high and amounted to 87.997%.

The indicator of the predictive accuracy of the risk of glaucoma progression was the area under the ROC curve - for the developed model it was 0.998 (p <0.001), which corresponds to the good quality of the model and indicates the high informative value of the proposed markers for predicting the risk of POAG development.

Thus, the totality of essential features makes it possible to determine the risk of POAG development based on the combination of age, hereditary, tonometric, and hemodynamic factors. The method provides obtaining data with high sensitivity and specificity for predicting the risk of POAG development.

The essence of the invention is illustrated by the following clinical examples.

Example 1. A 47-year-old female patient applied for a dispensary examination. She had no active complaints. She was worried about glaucoma due to her mother's diagnosis of POAG. Of the concomitant somatic diseases - disorders of the autonomic nervous system. Maximum visual acuity with 1.0 / 1.0 correction. IOP level with non-contact tonometry 16/17 mm Hg. The anterior chamber angle (APC) is open. With static automated perimetry (in the Central 22 mode, Tomey perimeter, Germany), a decrease in the average photosensitivity of the retina was revealed, the AD index was -0.96 dB for the right eye and -1.26 dB for the left. During ophthalmoscopy, the initial glaucomatous excavation of the optic disc in both eyes was determined. On OCT: RNFL for the right and left eyes 88/86 μm, the complex of retinal ganglion cells (GCS) on average - 87/90 μm, respectively, the volume of focal GCS losses - 0.27 / 1.15%, diffuse losses - 7.32 / 4.922%. In OCTA, the density of the vascular pattern at the level of the peripapillary layer of retinal nerve fibers was 67/62%. She was diagnosed with "Suspected glaucoma" in both eyes.

When calculating the integral risk factor for the development of glaucoma, the result was 2.088, which makes it possible to predict a high risk of developing POAG, despite the level of IOP within the statistical norm and the absence of pronounced functional visual impairments. The patient was recommended dynamic observation after 3 months, six months.

The woman appeared at the reception only after 1 year. During the examination, progression of disturbances in morphometric and perimetric parameters was observed, despite the IOP level of 17/17 mm Hg. the AD index was -1.21 dB for the right eye and -1.66 dB for the left. On OCT: the layer of retinal nerve fibers for the right and left eyes is 78/69 μm, the GCS complex is on average 83/79 μm, respectively, the volume of focal GCS losses is 1.39 / 2.02%, diffuse losses are 7.55 / 5 , 65%. Diagnosed with POAG Ia, normal pressure glaucoma in both eyes. Local antihypertensive treatment was prescribed.

Example 2. A 67-year-old female patient underwent follow-up examination after the diagnosis "Suspected glaucoma" in both eyes was established at the place of residence. She did not complain of decreased vision. Glaucoma heredity was not burdened. From concomitant somatic diseases noted chronic pancreatitis. On examination: visual acuity corrected for both eyes was 1.0. IOP level with non-contact tonometry 20/19 mm Hg. UPK is open. With computer perimetry, the AD index was -0.76 dB for the right eye and -1.31 dB for the left. With ophthalmoscopy of both eyes, the optic disc is pale pink, some expansion of physiological excavation, the ratio of excavation to the optic disc is 0.5-0.6. On the OCT: the layer of retinal nerve fibers for the right and left eyes is 89/86 μm, the GCS complex is on average 90.91 / 91.25 μm, respectively, the volume of focal GCS losses is 0.71 / 0.23%, diffuse losses are 2 , 1 / 2.79%. In OCTA, the density of the vascular pattern at the level of the peripapillary layer of retinal nerve fibers was 64/67%. Was diagnosed with "Mild myopia" in both eyes.

When calculating the integral risk factor for the development of glaucoma, the result was -1.021, which makes it possible to predict a low risk of developing POAG. The patient was recommended to follow up in dynamics. Examination after 8 and 15 months did not reveal a significant deterioration in morphometric and perimetric parameters, the IOP level was 19/19 mm Hg.

Example 3. A 72-year-old patient underwent follow-up examination by an ophthalmologist at the place of residence with a diagnosis of "Suspected glaucoma". Complains of decreased vision. Hereditary history of glaucoma was not aggravated. Among the concomitant somatic diseases, hypertension and ischemic heart disease were noted. Corrected visual acuity was 0.8 / 0.8. IOP level with non-contact tonometry - 21/21 mm Hg. The Criminal Procedure Code is open. Automated perimetry revealed a decrease in the average photosensitivity of the retina: the AD index was -2.26 dB for the right eye and -1.78 dB for the left. With ophthalmoscopy of both eyes, the optic disc pallor was determined, the ratio of excavation to the optic disc was 0.5. On OCT: the layer of retinal nerve fibers for the right and left eyes is 84/82 μm, the GCS complex is on average 85.92 / 82.44 μm, respectively, the volume of focal GCS losses is 0.758 / 1.451%, diffuse losses are 10.21 / 9 , 35%. In OCTA, the density of the vascular pattern at the level of the peripapillary layer of retinal nerve fibers was 60/62%. The diagnosis "Suspected glaucoma, incomplete complicated cataract" in both eyes was confirmed.

When calculating the risk coefficient for the development of glaucoma, the result was 0.297, which allows predicting a low risk of developing POAG, despite the level of IOP corresponding to the upper limit of the norm. Dynamic observation was recommended to the patient. Examination after 6 and 13 months did not reveal progression of disturbances in morphometric and perimetric parameters, the IOP level was 20/21 mm Hg. Diagnosed with "Incomplete complicated cataract" in both eyes.

Example 4. A 57-year-old patient was examined routinely. He did not complain of decreased vision. Glaucoma heredity is not burdened. From concomitant somatic diseases noted chronic gastritis, chronic cholecystitis. On examination: visual acuity corrected for both eyes was 0.9-1.0. IOP level with non-contact tonometry 20/20 mm Hg. The Criminal Procedure Code is open. With computer perimetry, the AD index was -1.76 dB for the right eye and -1.31 dB for the left. With ophthalmoscopy of both eyes, the optic disc is pale pink, the ratio of excavation to the optic disc is 0.5-0.6. On OCT: the layer of retinal nerve fibers for the right and left eyes is 90/88 μm, the GCS complex is on average 89.46 / 91.31 μm, respectively, the volume of focal GCS losses is -1.71 / 1.23%, diffuse losses are 4 , 21 / 2.33%). In OCTA, the density of the vascular pattern at the level of the peripapillary layer of retinal nerve fibers was 67/69%. The diagnosis was “Suspected glaucoma in both eyes.

When calculating the integral risk factor for the development of glaucoma, the result was 0.627, which makes it possible to predict a high risk of developing POAG. The patient was under the supervision of an ophthalmologist at the place of residence.

Comprehensive examination after 8 months showed progression of disturbances in morphometric and perimetric parameters, IOP level (with non-contact tonometry) 23/22 mm Hg. At perimetry, the AD index was -2.12 dB for the right eye and -1.56 dB for the left. On the OCT: the layer of retinal nerve fibers for the right and left eyes is 78/85 μm, the GCS complex is on average 81/79 μm, respectively, the volume of focal GCS losses is 2.01 / 1.62%, diffuse losses are 5.55 / 3 , 65%. Diagnosed with POAG Ib in both eyes. Local antihypertensive treatment was prescribed.

Example 5. A 71-year-old female patient underwent a comprehensive examination with self-admission. She complained of lacrimation, low vision. Family history of glaucoma is not burdened. From concomitant somatic diseases - GB, ischemic heart disease. Maximum visual acuity with 0.8 / 0.6 correction. IOP level with non-contact tonometry 19/20 mm Hg. The Criminal Procedure Code is open. Static automated perimetry revealed a decrease in the average light sensitivity of the retina, the AD index was -2.74dB for the right eye and -2.95dB for the left. With ophthalmoscopy, the optic disc of both eyes is pale, the ratio of excavation to the optic disc is 0.4-0.5. On OCT: RNFL for the right and left eyes 81/78 μm, the complex of retinal ganglion cells (GCS) on average - 80/75 μm, respectively, the volume of focal GCS losses - 2.82 / 3.25%, diffuse losses - 5.35 / 7.822%. In OCTA, the density of the vascular pattern at the level of the peripapillary layer of retinal nerve fibers was 66/65%. The diagnosis was "Suspected glaucoma, incomplete complicated cataract" in both eyes, "Age-related macular degeneration" in the left eye.

When calculating the integral risk factor for developing glaucoma, the result was 0.423, which makes it possible to predict a low risk of developing POAG. Dynamic observation was recommended to the patient.

Re-examination a year later did not reveal a significant progression of violations of morphometric parameters, the IOP level was 18/18 mm Hg. Was diagnosed with "Incomplete complicated cataract" in both eyes, "Age-related macular degeneration" in the left eye.

Claims (10)

A method for predicting the risk of developing primary open-angle glaucoma, including determining the ophthalmotonometry indicator and the presence of heredity burdened by glaucoma in a patient, calculating the risk of developing the disease using a mathematical formula, characterized in that the density of the vascular pattern at the level of the retinal nerve fiber layer is determined peripapillary according to optical coherence tomography with angiography and the patient's age, the current level of intraocular pressure is determined as an indicator of ophthalmotonometry, and the risk of developing the disease is calculated using the mathematical formula: PRR POAG = 5.679 * HEREDITY-0.087 * RPC_DENSITY + 1.677 * IOP-0.137 * AGE-19.823, where: PRR POAG - coefficient of risk of developing glaucoma; HEREDITY - the presence of heredity burdened by glaucoma, if present - 1, in the absence - 0; RPC_DENSITY — density of the vascular pattern at the level of the layer of nerve fibers of the retina, peripapillary,%; IOP - current level of intraocular pressure, mm Hg; AGE - age, years; 19.823 is a mathematical constant, and if the value of the risk coefficient for developing glaucoma is more than 0.5, a high risk of developing POAG is predicted.

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