RU2813151C2 - Method of diagnosing choroidal effusion after filter-type operations - Google Patents

Abstract

FIELD: medicine; ophthalmology.

SUBSTANCE: latent stage of choroidal effusion is diagnosed after filter-type operations using an optical coherence tomograph with an angiography function, in the Cross line spectral OCT mode with centring in the fovea, scanning the central parts of the fundus, including all layers of the choroid, sclera and sclerochoroidal interface, allowing the thickness of the choroid to be measured in a manual mode from the retinal pigment epithelium to the sclerochoroidal junction in the projection of the macular zone, within a radius of 500, 1,500, 2,500 mcm from the fovea in the upper, lower, nasal and temporal segments, assessing the structure and reflectivity of its layers. In the Radial Line mode, with the construction of 18 raster lines 12 mm long, an image of the optic nerve head and peripapillary parts of the retina, choroid and sclera is obtained to assess their relationships and the state of the sclerochoroidal interface. In both cases, attention is paid to the hyper-reflective contours increased in size and the hypo-reflective areas increased in diameter. The appearance of a hyporeflective slit-like space separating the sclera and choroid both in the central part of the fundus and peripapillary, associated with transudation of fluid from the vessels into the interstitial spaces, accompanied by a violation of the differentiation of the layers of the choroid, accumulation of fluid in the subchoroidal space, which determines the latent stage of choroidal effusion.

EFFECT: identification of choroidal effusion in the latent stage, determining its initial changes using OCT scanning, visualization of morphological changes in the choroid for the purpose of timely application of a pathogenetically based method of correcting this condition.

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Description

The invention relates to the field of medicine, namely to ophthalmology. Choroidal effusion (CE) (from the English effusion - effusion) is a complication that most often accompanies filtering surgical interventions for glaucoma, associated with a difference in intraocular pressure and/or depressurization of the eyeball during the operation [Fedorov S.N., Kozlov V. I., Timoshkina N.T. and others. Non-penetrating deep sclerectomy for open-angle glaucoma // Ophthalmosurgery. - 1989. - No. 3. - P.52-55; Cairns J.E. Trabeculectomy. Preliminary report of a new method. Am J Ophthalmol 1968; 66(4):673-679].

Disturbance of hydrostatic equilibrium caused by a decrease in pressure in the anterior part of the hydrostatic system of the eye is accompanied by a violation of the gradient between hydrostatic, osmotic and colloidosmotic pressure in the posterior segment, which causes a decrease in the natural hydraulic resistance of the vessels (arterioles) of the choroid and extravasation of protein-enriched fluid into the interstitial space, i.e. e. Choroidal effusion occurs, subsequently leading to ciliochoroidal detachment (CD).

According to the literature, ciliochoroidal detachment is the most common complication of filter-type operations, ranging from 15-75.3% of cases [Zharov V.V., Rykov V.P. Ciliochoroidal detachment (on issues of etiopathogenesis, prevention and treatment). RMJ. Clinical Ophthalmology 2009; 10(1):40-41; Petrov S.Yu., Podgornaya N.N. etc. Ciliochoroidal detachment. National Journal of Glaucoma, 2015, Vol. 14, No. 1, pp. 94-104.; Shaarawy T.M. et al. Guidelines on design and reporting of glaucoma surgical trials. Kugler Publications, 2009]. CHO is characterized by the accumulation of fluid in the suprachoroidal space. This is subsequently accompanied by paresis of the ciliary body with a decrease in the production of intraocular fluid (IOH) and the development of persistent hypotension, which eliminates the need for the functioning of the outflow tracts newly formed during the operation. The presence of CCO indirectly adversely affects the reparative processes in the newly formed outflow tracts by enhancing the inflammatory phase and, in some cases, is a trigger for scar transformations in the intervention area, which leads to the ineffectiveness of surgical intervention.

Therefore, increasing the accuracy of early diagnosis of this complication seems relevant.

The diagnosis of CCO is verified based on ultrasound data.

There is a known method for diagnosing CCO by ultrasound B-scanning. In case of flat detachment, the examination is carried out with the eye moving to the extreme to the side so that the scanning plane is parallel to the visual axis of the eye. Flat choroidal detachment appears as a hyperechoic linear structure with a characteristic expansion of the suprachoroidal space filled with hypoechoic contents. High detachment is detected in the axial scanning plane and has the appearance of rigid bubbles of a regular hemispherical shape [Shchuko A.G., Zhukova S.I., Yuryeva T.N. Ultrasound diagnostics in ophthalmology. - M.: Ophthalmology, 2013]. The disadvantage of this method is the inability to assess the morphological structure of choroidal tissue, as well as the diagnosis of already clinically significant CTO, which requires the use of long-term regimens of conservative therapy and/or surgical treatment methods.

There is also a known method for diagnosing CCO by ultrasonic biomicroscopy (UBM) [Glaucoma Therapy. State of the art. Edited by Matthias S. Grieshaber, 2009]. The study is carried out under local installation anesthesia using an immersion environment. The ultrasound probe is installed perpendicular to the structure under study (ciliary body), each of the four quadrants is examined, followed by fixation and evaluation of the image. Despite the high resolution of ultrasonic biomicroscopy, the disadvantage of this method is the need to use an immersion ring and instillation anesthesia, since this diagnostic method is contact. In addition, UBM is a method for diagnosing the anterior segment of the eye; it allows one to visualize only the area of the ciliary body and its spatial relationships without the ability to visualize the main volume of the choroid. Moreover, ciliary body detachment does not always accompany choroidal effusion in the early stages of development and does not occur initially, which is also uninformative at the preclinical stage of diagnosing CE.

The listed methods allow diagnosing only clinically significant CTO; they do not allow assessing the initial changes in choroidal morphology: the presence and severity of structural changes in the layers of the choroid in the macular region, peripapillary; thickness (in microns); and conduct a detailed assessment of the surface contours and sclerochoroidal interface throughout.

Thus, it is not possible to diagnose choroidal effusion in the latent stage using the methods described above, and the diagnosis of already clinically significant CTO with a fluid level in the subchoroidal space indicates a protracted pathological process and most often requires the use of surgical methods for correcting this condition.

The objective of the present invention is to increase the accuracy of diagnosing choroidal effusion in the latent (preclinical) stage in order to timely correct this condition and prevent the development of clinically significant CTO.

The technical result of the proposed invention is the detection of ChE in the latent stage, i.e. determination of its initial changes using OCT scanning, which makes it possible to visualize morphological changes in the choroid with the aim of timely application of a pathogenetically based method for correcting this condition.

The technical result is achieved by performing OCT of the posterior segment of the eyeball.

In order to verify the diagnostic value, the proposed method is carried out as follows.

Research is carried out on an optical coherence tomograph with angiography function. Analysis of scanning results consists of quantitative measurements of the choroid, assessment of its structure and reflectivity throughout. In the Cross line mode, spectral OCT with foveal centering in the horizontal and vertical directions scans the central parts of the fundus, including all layers of the choroid, sclera and sclerochoroidal interface. Choroidal thickness is measured manually from the retinal pigment epithelium to the sclerochoroidal junction in the projection of the macular zone, within a radius of 500, 1500, 2500 μm from the fovea in the upper, lower, nasal and temporal segments. The results of previous studies (if they were conducted previously), the choroidal thickness of the fellow eye (in the absence of pathology), or the average statistical values of these parameters in a healthy population can be used as reference values for choroidal thickness. Next, its structure and reflectivity are assessed. Normally, the segmentation of the choroid is preserved throughout: the choriocapillaris layer is defined as a narrow strip of moderate reflectivity adjacent to the “pigment epithelium - Bruch’s membrane” complex; Sattler's layer - a wide layer of round or oval hyperreflective contours with hyporeflective content; Haller's layer is a wide layer of oval hyperreflective contours with a hyporeflective center in the outer parts of the choroid adjacent to the sclera. The sclerochoroidal interface appears as a continuous homogeneous linear structure with a uniform degree of reflectivity along its entire length (Fig. 1).

In the Radial Line mode, with the construction of 18 raster lines 12 mm long, a high-definition image of the optic nerve head and peripapillary parts of the retina, choroid and sclera is obtained to assess their relationships and the state of the sclerochoroidal interface.

When assessing the structure of the choroid in the postoperative period, special attention is paid to the hyper-reflective contours of the structures, and hypo-reflective areas associated with the presence of cavities (vascular lumen, interlayer spaces).

Normally, in the postoperative period, in response to intraoperative decompression, there is an increase in the thickness of the choroid by no more than 30 microns, a moderate increase in the lumen of the vessels with preservation of their contours and a clear orientation of the layers. In this case, the state of the sclero-choroidal interface is visualized in the form of a linear continuous hyper-reflective homogeneous area.

The latent phase of ChE when scanning the choroid in the Cross line mode is characterized by a progressive increase in its thickness from 330 to 415 μm or more, elevation of the contour, decreased differentiation of layers (due to a decrease in the hyperreflectivity of the contours of the vessels) and an increase in the size of hyporeflective areas, indicating an increase in the diameter of the vessels and extravasation fluid from the vessels into the interstitial spaces (OCT - sign - an increase in the area of hyporeflective areas). As the process progresses, both in the Cross line mode and in the Radial line mode, a violation of the sclerochoroidal interface is observed - a hyporeflective slit-like space appears, separating the sclera and choroid both in the central part of the fundus and peripapillary. In addition, for the first time, accumulation of subchoroidal fluid was discovered peripapillary in a larger volume than in the central parts of the retina.

The signs discovered during scanning indicate a change in the structure of the choroid due to an increase in its volume, impaired differentiation of layers and an increase in hyporeflective areas, indicating a change in the hydrostatic buffer effect when hydrostatic equilibrium is disturbed after filter-type operations.

Knowledge of the etiology and mechanisms of development of CE allows us to take timely and adequate measures to carry out a set of preventive measures.

The OCT signs of choroidal effusion identified and described above are an indication for pathogenetically based treatment (introduction of viscoelastic into the anterior chamber to temporarily increase IOP and achieve hydrostatic equilibrium to prevent the development of CTO).

What is new is that optical coherence tomography of the posterior segment of the eyeball is performed in scanning modes of the central sections (Cross line) and peripapillary (Radial line), the thickness of the choroid is determined, its contour, differentiation of layers, vascular lumen are assessed, and the sclero-choroidal interface is characterized , based on the characteristics of changes in volume and degree of reflectivity of structures when diagnosing signs of CE.

What is also new is that the method makes it possible to detect the listed changes even with normal dimensions of the anterior chamber and in the presence of a filtration cushion.

What is also new is that in the Radial line mode, the presence of effusion in the subchoroidal space, preceding effusion in the central parts of the fundus, is detected peripapillarily.

What is also new is that OCT signs of choroidal effusion were described for the first time, confirming the pathogenetic mechanisms of its development. Also, for the first time, the pathogenetic mechanisms of intracameral administration of viscoelastic have been shown, justifying a short-term increase in IOP as a therapeutic procedure that prevents the development of CTO.

Thus, thickening of the choroid, impaired differentiation of its layers and disruption of the sclero-choroidal interface are diagnostic markers of the latent stage of cholecystitis, preceding the development of CHO, which is an indication for pathogenetically based treatment - intracameral administration of viscoelastic for a short-term increase in IOP and, accordingly, achieving hydrostatic equilibrium aimed at preventing the development of CTO in the early postoperative period.

In addition, the described OCT signs of the development of CE at the preclinical stage justify the need to use the technique of tight closure of the scleral flap during penetrating filter-type operations.

The method is illustrated with clinical examples.

Clinical example 1.

Patient K, 62 years old, was admitted to the Institute of Medical Sciences and Technology "Eye Microsurgery" named after. acad. S.N. Fedorov with a diagnosis of primary open-angle glaucoma (POAG) I in the left eye. IOP (Pt) on admission 35 mm Hg. on the maximum medication regimen (MMT). Surgical treatment was performed - non-penetrating deep sclerectomy using standard technology. After peritomy of the conjunctiva with a length of 6-7 mm, cutting out a superficial scleral flap measuring 3.5x3.5 mm, by removing the scleral-corneal block and removing the inner wall of Schlemm’s canal, a “window” of the trabeculo-Descemet membrane (TDM) was formed, a flow of intraocular fluid was obtained from anterior chamber into the scleral bed. The scleral flap is reduced and fixed at the corners with immersed interrupted sutures in the scleral bed. At the final stage, a filtration cushion is formed over the scleral flap by simultaneously fixing the Tenon's capsule and conjunctiva to the cornea with interrupted corneo-sclero-conjunctival submersible sutures with a 10.0 thread.

On the next day after surgery, AF was flat, diffuse, anterior chamber (AC) of medium depth, uniform, IOP 9 mm Hg, no signs of CCO were detected according to UBM and B-scan data. Given the low intraocular tone, the patient underwent OCT to assess the condition of the choroid (Fig. 2). According to OCT, the thickness of the choroid is increased by 120 mm, contour elevation, decreased differentiation of layers and an increase in hyporeflective areas are observed (due to a decrease in the hyperreflectivity of the vascular contours), which indicates vascular dilation and extravasation of fluid into the interstitial space (Fig. 2, red arrow). Also on OCT scans the sclerochoroidal fissure from the optic disc in the direction of the central sections is visualized (Fig. 2, yellow arrow). Thus, according to OCT scanning data, a diagnosis can be made: Choroidal effusion (latent stage) of the left eye.

For a comparative analysis, an OCT scan of the choroid of the same patient was used, performed at the stage of diagnostic examination before surgical treatment (Fig. 3). To prevent the progression of the process and the development of CTO, a paracentesis of the cornea of the left eye was performed and a viscoelastic ophthalmic solution DisCoVisc in a volume of 0.2 ml was injected into the anterior chamber. A short-term increase in IOP was achieved. The next day, according to OCT data, the thickness of the choroid decreased, the contour was correct, and differentiation of the layers was visualized. The sclerochoroidal fissure is not identified. IOP 14 mm Hg. Art., no signs of choroidal effusion were detected (Fig. 4 shows the choroid after intracameral administration of a viscoelastic ophthalmic solution and a short-term increase in IOP on the 4th day after surgery). The patient was discharged under the supervision of an ophthalmologist at her place of residence with dynamic monitoring of IOP and functions.

Clinical example 2.

Patient Sh., 64 years old, was admitted with a diagnosis of primary open-angle glaucoma (POAG) II B of the right eye. IOP (Pt) on admission 32 mm Hg. on the maximum regimen of antihypertensive drugs. Surgical treatment was performed - trabeculectomy ab externo. After peritomy of the conjunctiva with a length of 6-7 mm, cutting out a superficial scleral flap measuring 3.5x3.5 mm, an internal fistula was formed by excision of the corneoscleral block in the trabecular area with a Kelly's Punch device, a basal iridectomy was performed, the scleral flap was reduced into the scleral bed, fixed with 4 with immersed interrupted seams in the corners and parallel to the limbus area. At the final stage, a filtration cushion is formed over the scleral flap by simultaneously fixing the Tennon capsule and conjunctiva to the cornea using interrupted corneo-sclero-conjunctival submersible sutures with 10.0 thread.

On the 2nd day after the operation, the filtration cushion is flat, spilled, the anterior chamber is of medium depth, with ophthalmoscopy of the fundus the reflex is pink, uniform, IOP 7 mm Hg. Taking into account postoperative hypotension, OCT was performed in Cross Line and Radial Line modes (Fig. 5). According to OCT, there is a decrease in the differentiation of layers and an increase in hyporeflective areas (due to a decrease in the hyperreflectivity of the contours of the vessels), the sclero-choroidal fissure is visualized in the central sections (Fig. 5, red arrow) and peripapillary from the optic disc (Fig. 5, yellow arrow). Based on OCT scan data, a diagnosis was made: Choroidal effusion (latent stage) of the right eye.

Violation of the sclero-choroidal interface in the central sections and peripapillary was an indication for intracameral administration of the viscoelastic ophthalmic solution DisCoVisc in a volume of 0.2 ml. A short-term increase in IOP was achieved. The next day, a control OCT scan was performed (Fig. 6). According to OCT, the thickness of the choroid is normal, the contour is correct, the differentiation of layers is visualized. The sclerochoroidal fissure is not defined both in the central sections (Fig. 6, red arrow) and peripapillary (Fig. 6, yellow arrow). IOP 14 mm Hg. Art., no signs of choroidal effusion were detected.

The patient was discharged under the supervision of an ophthalmologist at the place of residence with dynamic monitoring of IOP and functions.

Claims (1)

A method for diagnosing the latent stage of choroidal effusion after filter-type operations using an optical coherence tomograph with an angiography function, which consists in using the Cross line spectral OCT mode with centering in the fovea, scanning the central parts of the fundus, including all layers of the choroid, sclera and sclerochoroidal interface, allowing measurement manual thickness of the choroid from the retinal pigment epithelium to the sclerochoroidal junction in the projection of the macular zone, within a radius of 500, 1500, 2500 μm from the fovea in the upper, lower, nasal and temporal segments, assessing the structure and reflectivity of its layers; in the Radial Line mode with the construction of 18 raster lines 12 mm long, obtaining an image of the optic nerve head and peripapillary parts of the retina, choroid and sclera, to assess their relationships and the state of the sclerochoroidal interface; in both cases, paying attention to the hyperreflective contours increased in size and hyporeflective areas increased in diameter, to the appearance of a hyporeflective slit-like space separating the sclera and choroid both in the central part of the fundus and peripapillary, associated with the transudation of fluid from the vessels into the interstitial spaces, accompanied impaired differentiation of the layers of the choroid, accumulation of fluid in the subchoroidal space, which determines the latent stage of choroidal effusion.