RU2314033C1 - Method for diagnosing preglaucoma and early stage primary open angle glaucoma - Google Patents

Abstract

FIELD: forensic medicine.

SUBSTANCE: method involves determining ratios of excavation volumes and neuroretinal belt volumes for disk as a whole and in sector-by-sector way. The obtained values are compared to upper boundaries of preliminarily determined reference values. Preglaucoma diagnosis is set, if a reference value is exceeded at least in one sector or for the disk as a whole. Early stage primary open angle glaucoma is diagnosed when scotomas in vision fields are found to be available at the same time.

EFFECT: enhanced effectiveness in detecting structural transformations in optic nerve disk before functional changes are manifested.

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Description

The invention relates to medicine, in particular to ophthalmology, and can be used in glaucoma centers, eye offices and clinics to identify the glaucomatous process in the early stages of the disease.

A known method for the early diagnosis of glaucoma, based on the study of changes in the parameters of the optic disc (hereinafter referred to as optic disc) using optical coherence tomography (I. G. Neyasova. In the collection of articles of the conference for doctors of central hospitals, diagnostic centers and military clinics of the Ministry of Defense of the Russian Federation "Glaucoma: Theories , Trends, Technologies. HRT Club Russia-2005 ”from 09.12.2005, Moscow, p.239).

According to this method, the shape and depth of excavation, the ratio of the area of excavation and the area of the optic nerve disc, the position of the level of the neuroretinal girdle and its volume are determined, the thickness and structure of the peripapillary nerve fibers are examined.

The early signs of the initial stage of glaucoma are:

- gentle wide excavation with a characteristic smooth excavation in the zone of the neuroretinal girdle (URP);

- an increase in the ratio of the excavation area to the area of disability compared with the norm;

- the position of the level of the URP of the temporal half of the optic nerve disc - its "subsidence";

- a decrease in the volume of ILP compared with the norm, which indicates the phenomena of thinning and partial atrophy of the nerve fibers of the optic nerve disc;

This method has several disadvantages, in particular: for research, transparent media and mydriasis of at least 5 mm are required, to obtain reliable data, ~ 12 measurements are necessary, the data are based on average values, the positioned image of the optic disc is associated with the position of the subject during the study, which complicates the early diagnosis and reduces its reliability.

The closest in technical essence and the achieved result is a method for the early diagnosis of glaucoma by measuring the parameters of the disability using the Heidelberg Retina Tomograph confocal laser scanning system (HRT-I and HRT-II) (ABKuroedov, S.Yu. Golubev, G.V.Shafranov Glaucoma, No. 2, 2005, pp. 7-18. "The study of the morphometric criteria of the optic nerve head in the light of the possibilities of modern laser diagnostic technology." Prototype).

This method provides for the measurement of morphometric parameters of the area of DZN, the depth of excavation of DZN, the total area of the URP for 7 age groups is normal and with glaucoma. In this case, the indicators obtained in glaucoma eyes are compared with the average values of the indicators in the norm, and therefore the method is not sufficiently informative.

The objective of the invention was to develop a sensitive parameter retinotomographic studies of preglaucoma and early stage open-angle glaucoma.

The essence of the invention lies in the fact that they examine changes in the optic nerve at the stage when functional changes are not yet detected, for which the volume of excavation by the opticonvascular disc in general and by sectors and the volumes of the neuroretinal girdle are measured on a retinal tomograph of the Heidelberg Retina Tomograph system.

As a sensitive parameter for determining preglaucoma, the ratios of excavation volumes of the ZN disk as a whole and by sectors to the corresponding volumes of the neuroretinal girdle cup / rim volume ratio, conventionally designated Кр - retinotomography coefficient are used.

The obtained values of Cp are compared with the upper limit of the norms established previously in healthy eyes, and in case of exceeding the norms for the optic disc in general or at least one of the sectors is diagnosed with preclaucoma.

With the further development of the disease, the values of Cp increase both in the optic disc and in the sectors, and when cattle appear in the fields of vision, they diagnose the early stage of open-angle glaucoma.

The technical result from the use of this invention is expressed in the following:

- for the diagnosis of preglaucoma, data are used on structural changes in the disability that occur earlier than functional changes;

- the early stage of primary open-angle glaucoma is determined with an increase in Cr values and the simultaneous appearance of livestock specific for glaucoma in the fields of vision.

The proposed method for the early diagnosis of preglaucoma and early stage glaucoma is as follows. Preliminarily, the parameters of the optic disc and its sectors are measured in healthy eyes and the lower and upper limits of the norm are determined. (When developing this method, measurements were taken on 206 healthy eyes of volunteers.) In this case, depending on the area of the optic disc, the parameter values were considered in 3 groups: <1.5 mm ² , 1.5-2.5 mm ² and from 2 5 to 3.0 mm ² . The obtained values are presented in table 1.

When patients with increased IOP or subjective complaints about the condition of the eyes are treated, retinotomographic examinations of the optic nerve disc are performed, the values of CR are determined by the optic discs in general and by sectors, and the obtained values are compared with the corresponding upper normal values. If the Kr norm is exceeded, the disc as a whole or at least one of the sectors is diagnosed with preclam, and then the patient is monitored in dynamics.

In case of negative dynamics of Cp values and the appearance of specific cattle in the fields of vision, the early stage of primary open-angle glaucoma is diagnosed and appropriate treatment is prescribed to the patient.

Table 1 Norms Cr. established during the examination of 206 healthy eyes of volunteers Groups The area of optic disc, mm ² By sector DZN in general T TS Ti N NS Ni I <1.5 0-0.26 0-4.1 0-0.18 0-0.75 0-0.04 0-0.02 0-0.26 II 1.5-2.5 0-1.1 0-7.0 0-1.65 0-1.5 0-0.6 0-1.1 0-0.42 III > 2.5 0-1.1 0-8.8 0-1.9 0-2.6 0-0.44 0-1.1 0-0.6 Sectors: T - temporal TS - superior temporal TI - Low-temporal N - nasal NS - nasal NI - nasal

Example 1. Patient R., born in 1931.

When handling had increased intraocular pressure (29 mm Hg) of the left eye (OS).

The area of the optic disc is 1.514 mm ² , i.e. the patient belongs to the middle group according to the value of the area of optic discs.

On October 4, 04, the first retinotomographic examination was carried out, the results obtained are shown in Table 2. During the initial examination, deviations from the norm were observed only in the temporal sector, in the disk as a whole and in other sectors, the indicators remained normal. No changes in the field of view were detected. The patient was diagnosed with preglaucoma, and it was suggested that further observation be made.

12/07/04, the second retinotomographic examination was carried out, while the negative dynamics of CR was observed in the whole ZN disk, and in the temporal sector - a significant excess of the norm.

In the fields of vision, single scotomas were observed in the nasal segment. Against the background of uncompensated IOP, based on the data of retinotomography and perimetry, an early stage of open-angle glaucoma was diagnosed and treatment was prescribed.

For example 1.

The disk area is 1.514 mm ² , patient R., a.k. No. 150926

table 2 The values of CR obtained during the examination Sectors Norma (upper bound) Survey Conclusion 1st 4.10.04 2nd 7.12.04 DZN 1,1 0.37 0.42 At the first examination in the temporal sector, the value of Cr exceeds the norm, and therefore preglaucoma is diagnosed T 7.0 9.0 15,5 TS 1.65 0.8 0.92 Ti 1,5 0.3 0.24 N 0.6 0.01 0.008 NS 1,1 0.34 0.225 Ni 0.42 - -

Retinotomographic examination data are presented in the appendix - tables 1-1 and 1-2.

Example 2

Patient S., A.K. No. 142761

When turning on the right eye had IOP - 27 mm Hg, there were no changes in the fields of view. The area of the optic disc is 1.848 mm ² .

On April 28, 2004, the first retinotomographic examination was carried out, the results obtained are presented in table 3. During the examination, a deviation of the Kr value was noted only in the upper temporal sector, the remaining indicators did not exceed the upper norm value. No changes in the field of view were detected. The patient was diagnosed with preclaucoma and offered treatment with myotics and further observation.

On September 13, 2004, a second retinotomographic examination was carried out, in which a negative dynamics of Cr was found, while in three sectors its values went beyond the upper limit of the norm. In the fields of vision, scotomas were observed in the nasal segment, the pressure was not compensated: the diagnosis was an early stage of glaucoma. The patient is reinforced with a mystical treatment regimen and further observation is suggested.

For example 2. Patient S., a.k. No. 142761

Table 3 Sectors Upper limit of normal Survey Conclusion 1st 28.04.04 2nd September 13, 2004 DZN 1,1 0.46 0.98 At the first examination of the value, preglaucoma was diagnosed, at the second - stage 1 of primary open-angle glaucoma. T 7.0 1.72 6.6 TS 1.65 2,3 5,0 Ti 1,5 0.7 1.05 N 0.6 0.55 0.02 NS 1,1 0.63 1.35 Ni 0.6 0,07 0.16

Retinotomographic examination data are presented in the appendix, tables 2-1 and 2-2.

Example 3

Patient G., born in 1948.

The area of optic discs is 1.731 mm ² (2nd group).

The patient complained of blurred vision of the right eye. IOP OD = 27 mm Hg

10.25.06, the patient underwent the first examination. No changes in the field of view were detected. Retinotomography data are presented in table 4. A deviation from the norm of Kr was noted in the inferior temporal sector, in connection with which the diagnosis of preglaucoma was made. The patient was prescribed miotics for instillation into the eye. Further observation recommended.

01/17/07, a re-examination. Scotomas characteristic of open-angle glaucoma were found in the fields of vision.

A retinotomographic examination (see Table 4) revealed an excess of the Kr norm in the inferior temporal sector and an increase in Cr in the other five sectors.

The patient was diagnosed with stage I of primary open-angle glaucoma and 0.5% betoptic was prescribed.

Table 4
For example, number 3. Patient G., the area of the optic disc is 1.731 mm ² . Sectors Upper limit of normal Survey Conclusion 1st 10/25/06 2nd 01/17/07 DZN in general 1,1 0.7 0.7 At the first examination of the value, preglaucoma was diagnosed, at the second - stage 1 of primary open-angle glaucoma. T 7.0 4.7 5.8 TS 1.65 1,2 1.3 Ti 1,5 1,6 1.9 N 0.6 0.1 0.1 NS 1,1 0.5 0.6 Ni 0.6 0.3 0.4

Retinotomographic examination data are presented in the appendix - tables 3-1 and 3-2.

Claims (1)

A method for the diagnosis of preglaucoma and the early stage of primary open-angle glaucoma, including retinotomographic measurement of the parameters of the optic disc, characterized in that they determine the ratios of the volumes of excavation of the optic disc as a whole and across sectors to the corresponding volumes of the neuroretinal girdle and if the maximum values of the norms of these relationships are exceeded, although if one sector or disk as a whole is diagnosed with preclaucoma, while the presence of livestock in the fields of vision is diagnosed with early tadium primary open-angle glaucoma.