RU2262892C1 - Method for diagnosing optic nerve abnormality in the cases of endocrine ophthalmopathy - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves examining retina light sensitivity degree using computer-aided perimetry approach within 60° bandwidth from fixation point. Direct orbital muscle thickness and retrobulbar space volume is additionally determined by applying ultrasonic b-scanning method. Linear blood circulation speed and resistance index are also determined in the central retinal artery and posterior short ciliary arteries. Macular or general light sensitivity reduction 25% and more relative to age-specific norm being observed together with 50% growth and more in direct orbital muscle thickness, retrobulbar space volume growth by more than 35% in combination with linear blood circulation speed reduction in the central retinal artery and posterior short ciliary arteries by 40% and more and increasing resistance index by 20% and more relative to physiologic norm, optic nerve abnormality is diagnosed at early disease stages.

EFFECT: high reliability of diagnosis.

2 tbl

Description

The invention relates to medicine, namely to ophthalmology, and is intended for the early diagnosis of optic nerve pathology in endocrine ophthalmopathy.

The term ″ endocrine ophthalmopathy ((EO) is used to define eye damage manifested by exophthalmos, swelling of the orbital tissues, and changes in the eye muscles. According to the literature, 2/3 of patients with EO have visual impairment due to pathology of the optic nerve and retina (A.F. Brovkina et al. Edematous exophthalmos and optical neuropathy // collection ″ Eroshevsky readings ″, Samara-2002 - p.595-596).

The determination of the essential features that make it possible to identify early signs of optic nerve pathology in endocrine ophthalmopathy is of great medical and social importance, and, therefore, such a study is relevant and appropriate. There are several methods for diagnosing pathology of the optic nerve based on electrophysiological studies and a comparative assessment of various parameters of the bioelectric activity of the visual analyzer.

A known method for the diagnosis of optic nerve pathology (RF Patent No. 2134054, Bull. Inventory No. 22, 1999), which provides a comparative assessment of the parameters of the optic nerve disk (optic disc) of a patient with an existing reference image of optic disc for various diseases, and with the coincidence of most indicators, character is diagnosed pathology. The disadvantage of this method is its low diagnostic significance in the early stages of the disease, when visual functions are reduced, and objective changes in optic disability are scarce.

A known method for diagnosing pathology of the optic nerve (RF Patent No. 1814536, Bull. Inventory No. 17, 1993) based on determining the size of the blind spot, and with an increase in this indicator diagnose pathology of the optic nerve. The disadvantage of this method is the narrow range of its application, because it reveals the development of only edema of the optic nerve disc, while pathology of the optic nerve can develop without edema of the optic nerve disc.

A known method for diagnosing pathology of the optic nerve (RF Patent No. 2098008, Bull. Inventory No. 34, 1997), in which they measure the threshold of brightness sensitivity in the center of the field of view in a row, and when scattering answers to 0, 4 logarithmic units or more diagnose a pathological condition optic nerve. The disadvantage of this method is the high probability of overdiagnosis of the pathology of the optic nerve in patients with endocrine ophthalmopathy, because in this disease, hormonal and vascular changes have a significant effect on the bioenergetics of the optic nerve, changing it to varying degrees, but the visual functions remain high for a long time.

A known method for the diagnosis of pathology of the optic nerve and retina (RF Patent No. 2187238, Bull. Inventory No. 23, 2002), which provides a quantitative assessment of electrophysiological parameters: threshold of electrical sensitivity (EL) of the retina and electrical lability of the optic nerve in the original the state and 1 hour after a single dose of Wobenzym in the amount of 5-7 tablets, with a decrease in the threshold of EC by 20 μA and an increase in the threshold of EL by 5 Hz, a conclusion is drawn about the reversible nature of damage to the optic nerve and retina. The disadvantage of this method is its low information content with endocrine ophthalmopathy, because changes in orbit are not taken into account. With endocrine ophthalmopathy, an increase in the thickness of extraocular muscles and compaction of retrobulbar space occurs. These changes in the orbit have a negative effect on the orbital and retinal blood flow and on the functional state of the optic nerve.

The closest analogue to the claimed method and taken as a prototype is the "Method for the diagnosis of pathology of the retina and optic nerve" (RF Patent No. 2207039, Bull. Inventory No. 18, 2003), the essence of which is the study of light sensitivity in the range of 60 degrees from the point fixing with the calculation of the probability of the correspondence function between the level of light sensitivity at central points and on the periphery of the field of view. Pathology is diagnosed when the maximum likelihood of matching the compared functions is achieved by excluding the threshold contrast values from the domain of definition. The disadvantage of this method is the complexity of assessing the type of pathology, limited application, because there is no such computer program in widespread use.

The technical task is to develop a method for the diagnosis of optic nerve pathology in patients with endocrine ophthalmopathy in the early stages of the disease. The technical result is achieved by the fact that a patient with endocrine ophthalmopathy is examined the level of light sensitivity of the retina by computer perimetry in the range of 60 degrees from the fixation point, the thickness of the rectus muscle of the eyeball and the volume of retrobulbar space by ultrasonic b-scanning, as well as the linear blood flow velocity (LSC) are additionally determined ) and the resistance index (IR) in the central retinal artery (CAC) and the posterior short ciliary arteries (SCCA) with a decrease in the level of macular and (or) total retinal light sensitivity of 25% or more with respect to the age norm, an increase in the thickness of the rectus muscles by 50% or more, an increase in the volume of retrobulbar space by more than 35% in combination with a decrease in BFV in the CAC and SCCA by 40% or more, with an increase in IR by more than 20% with respect to the physiological norm, pathology of the optic nerve is diagnosed in the early stages of the disease.

The development of the proposed method for the diagnosis of optic nerve pathology in patients with endocrine ophthalmopathy was based on the results of a comprehensive study of 42 patients with a diagnosis of diffuse goiter, endocrine ophthalmopathy. Dynamic observation over 2 years of the clinical development of the disease and a comparative assessment of ophthalmic parameters with a control group of practically healthy individuals of a similar age (24-40 years) made it possible to identify significant signs that affect optic nerve damage and diagnose this pathology in the early stages of EO in 71.4%. Anatomical and physiological indicators of the state of the orbit and the eyeball in people of the control group and in people with endocrine ophthalmopathy (EO) with long-term preservation of visual functions and pathology of the optic nerve are presented in table 1.

The analysis of the obtained results in a comparative aspect in percentage terms showed that, with a favorable clinical course of EO with high visual acuity and peripheral visual field boundaries, the change in anatomical parameters does not exceed 20% with respect to the physiological norm, and the dynamics of physiological parameters does not exceed 15%. With the development of pathology of the optic nerve in the form of atrophy in patients with EO, anatomical indicators rapidly deteriorate more than 40%, and physiological ones - more than 25% in relation to the norm (table 2).

table 2
Dynamics of changes in the anatomical and physiological parameters (in%) with a different state of the visual analyzer indicators Visual analyzer status stable worsening Macular light sensitivity A decrease of 10-15%, on average - 11.6% A decrease of 25-30%, on average - 28.1% Total light sensitivity Decrease by 10-15%, on average -14% A decrease of 25-30%, on average - 27.1% Straight eye muscle thickness An increase of 10-15%, on average - 11.8% An increase of 50-70%, on average - 64.4% The volume of retrobulbar space (mm3) An increase of 10-15%, on average - 14.8% 35-40% increase, on average -41.5% GA LSK
IR

CAC LSK
IR

WCCA LSK
IR

The method is as follows

A patient with endocrine ophthalmopathy is examined for the level of macular and total light sensitivity of the retina using static computer perimetry at the computer perimeter of Torsop (Japan), then, using ultrasound scanning of the orbit on the Acuson apparatus, LSC in CSC and CAC are determined, after which the volume of retrobulbar is determined by the method of B-scan of the orbit the space and thickness of the rectus eye muscles, the results are compared with the physiological norm of the corresponding indicators. With a decrease in the macular and (or) total light sensitivity of the retina by 25% or more, an increase in the volume of retrobulbar space by more than 35%, and the thickness of the rectus muscles by 50% or more in combination with a decrease in BFV in the CAC and SCCA by 40% or more , with an increase in the resistance index (IR) in these vessels by 20% or more with respect to the physiological norm, pathology of the optic nerve is diagnosed in the early stages of the disease.

As a confirmation of the data presented, we present a clinical example:

Patient P. (amb. Source of illness 21/2003), 38 years old, turned to the regional clinical hospital of Rostov-on-Don for a consultation about exophthalmos, pain in the eyeball.

Vis OD = 1.0 IOP = 18.0 mm Hg

Vis OS = 1.0 IOP = 20.0 mmHg

Exophthalmometry - with a base of 98 mm, the distance of the right eye - 23 mm

left eye - 25 mm

The patient, according to the proposed method, was investigated light sensitivity of the retina of both eyes. Computer perimetric data: the level of macular light sensitivity of the right eye was 214 dB (which is 27% below the physiological norm), the level of total light sensitivity was 1637 dB (which is 26% below the norm). Visual acuity of both eyes = 1.0. The anterior segment without features, the fundus of the eye is an optic nerve disc pale pink, the borders are clear, the arteries are evenly narrowed, the veins are dilated, the ratio of the caliber of the vessels is A / B = 1/3.

Ultrasound scan data of orbital vessels (LSC, IR)

Right - CAC - 9 cm / sec (IR-0.7)

ZKCA - 10 cm / sec (IR-0.72)

Left - CAC - 8 cm / sec (IR-0.7)

ZKCA - 9 cm / sec (IR-0.71).

The data obtained indicate a decrease in volumetric blood flow in the ophthalmic arteries (CAC and SCCA) by 45-50% with respect to normal.

An ultrasound study of the orbit showed that on the right the thickness of the rectus muscles is 6.7 mm, and the volume of the retrobulbar space is 25.9 mm ³ . The data obtained indicate an increase in these indicators by 41-46% in relation to the norm.

Based on a combination of symptoms, a diagnosis was made - endocrine ophthalmopathy, a descending partial atrophy of the optic nerve in both eyes.

ATP preparations of 1.0 v / m N 20 were recommended; sermion 1 tab. 2 r per day for 1 month.

A repeated examination after 6 months showed a decrease in visual acuity to 0.8 in both eyes, a narrowing of peripheral borders by 10-15 degrees across all meridians, and the presence of a central relative scotoma. On the fundus was determined blanching of the optic disc, signs of venous dilatation. Ultrasound scanning of the orbital vessels confirmed the same data as during the initial examination. LSC in CAC 9-8 cm / sec, IR -0.7-0.73 in the right and left eye, respectively. An ultrasound study of the orbit showed an increase in the thickness of the rectus muscles of the eyeball up to 7 mm and retrobulbar space up to 26 mm ³ . Exophthalmos also intensified, exophthalmometry data:

Standing right eye = 24 mm left eye = 26 mm basis = 98 mm.

This example shows that after 6 months the diagnosis of optic atrophy became apparent, the decline in visual function, registered by simpler diagnostic equipment, progressed. The obtained results confirmed the diagnosis of optic atrophy at earlier stages of endocrine ophthalmopathy.

Based on the studies, we can conclude that, in comparison with the prototype, the claimed "method for the diagnosis of optic nerve pathology in endocrine ophthalmopathy" allows for early diagnosis of optic nerve damage, depending on the combination of essential distinguishing features.

Claims (1)

A method for diagnosing optic nerve pathology in endocrine ophthalmopathy by determining the light sensitivity of the retina, characterized in that it further determines the thickness of the rectus muscles of the eyeball, the volume of retrobulbar space, the linear blood flow velocity (LSC) and the resistance index (IR) of the central retinal artery (CAS) and posterior short ciliary arteries (SCCA) with a decrease in the level of macular and (or) total light sensitivity of the retina by 25% or more, an increase in the thickness of rectus muscles by 50% or more, an increase and the volume of retrobulbar space by more than 35% in combination with a decrease in BFV in the CAC and SCCA by 40% or more, with an increase in IR by more than 20% with respect to the physiological norm, the pathology of the optic nerve is diagnosed in the early stages of the disease.