RU2480141C1 - Method of lacrimal tract examination - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to ophthalmology and is intended for examination of lacrimal tract. Lacrimal tract is washed a day before examination. As contrast substance used is Visipaque in concentration 320 mg/ml. Visipak is introduced through infusion system with infusion rate 400 ml/hour, with infusion volume 5 ml, infusion time 2 min. Simultaneously with visipaque introduction carried out is multispiral computed tomography with volume dynamic scanning with 0.5 mm thick cut and 0.25 mm interval in axial projection. Multiplanar and three-dimensional reconstructions are built.

EFFECT: ensured are: possibility of adequate visualisation of anatomofunctional peculiarities of lacrimal tract along entire length with determination of delacrimation phases, as well as determination of the level and degree of lacrimal tract obstruction, its possible cause, which makes it possible to determine further treatment tactics with greater accuracy.

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Description

The present invention relates to ophthalmology and is intended for the study of tear ducts (SOP) using their contrast when performing dynamic multispiral computed tomography (DMSC).

Existing traditional dacryoradiography does not always provide the necessary information about the pathological process. Proposed by many authors (Lupan D.S. et al., Comparative evaluation of X-ray diagnostics of patency of the tear ducts. VII Republic scientific conference. Radiologists and radiologists. Chisinau, 1980. p.203-204, Malinovsky G.F. et al. Practical guidelines for the treatment of diseases of the lacrimal organs. Minsk, 2000. 192 p., Mehrotra AS Distension dacryocystography and its results in normal and epiphora cases. Indian J. Ophthalmology. 1984; 32 (5): 364-367) methods for studying SOPs (stereoradiographic method , macrodacryocystography, dacryocystography with numerical subtraction) are aimed at studying the anatomical topograph the physical properties of the lacrimal system, the study of the functional state of the lacrimal system is difficult. Work Avetisyan A.B. (1983) is devoted to the study of the mechanism of lacrimation. Using the methods of traditional dacryocystorentography, serial radiography and X-ray cinematography, the author made the following conclusions: when conducting a standard radiography technique, contrast is not introduced at the time of the study, which leads to premature emptying of the SOP and obtaining distorted SOP X-ray data; developed a special device designed for the introduction of contrast medium into SOP under a minimum pressure of 25 mm Hg during X-ray imaging, allows you to enter a contrast agent during the study, which makes it possible to study the mechanism of lacrimation (phase filling and emptying of the SOP).

Today, new diagnostic capabilities are associated with the widespread introduction in clinical practice of modern radiation diagnostic methods, such as multispiral computed tomography (MSCT). Most of the methods of MSCT of the lacrimal system are aimed at assessing the bone bed of SOP and their relationship with the structures of the nose, to exclude concomitant rhinopathology, with traumatic dacryocystitis, to accurately determine surgical access, as well as to evaluate the results of an unsuccessful dacryocystorhinostomy (Atkova E.L. et al. Assessment of the condition of the lacrimal passages according to computed tomography CT in the clinic: Thesis, report of the I All-Union Symposium Moscow, 1987, pp. 53-56, Bobrov DL The role of endoscopy and comp computed tomography in the diagnosis of pathology of the nasal cavity and paranasal sinuses in patients with chronic diseases of the tear ducts, Russian Rhinology, 2002; 3: 21-24, SKFreitag et al. Helical computed tomography with three - dimensional reconstruction. A new view of the lacrimal drainage system.Ophthal Plast Reconstr Surg 2002, 18: 121-32, P. Udhay et al. Helical computed tomographic dacryocystography and its role in the diagnosis and management of lacrimal drainage system blocks and medial canthal masses, p: 35-37 Medical Research Foundation , Chennai, India, 2008).

Thus, with the help of MSCT, the anatomical and morphological features of the lacrimation system were studied, and the functional properties of the tear ducts in the dynamic range of MSCT have not been studied to date.

A known method for the study of SOP, including the introduction of a contrast agent "cardiotrust" with a content of 50% iodine in SOP using the developed special device. All patients underwent a general dacryological examination, including external examination, pressure on the area of the projection of the lacrimal sac, tubular and nasal tests, washing with SOP. The SOPs were contrasted using the generally accepted methodology and the proposed methodology for the dosed introduction of contrast agents into SOPs using the developed special device. Then, X-ray studies were carried out: conventional radiography, serial radiography and cinematography. The study of the mechanism of lacrimation was performed using serial radiography and X-ray cinematography. Subsequently, a comparative assessment of the results of X-ray cryocystography was carried out with various methods of introducing cotrast into SOPs (Avetisyan A.B. New method of dacryo-radiography and its significance in the diagnosis of diseases of the tear ducts. Diss. ... Candidate of Medical Sciences. Moscow, 1983).

However, the method has the following disadvantages: the exclusion of the possibility of further computer processing and analysis of the obtained data, in addition, the metal needle-cannula used to supply contrast to the SOP can lead to trauma to the lacrimal tubules and the appearance of artifacts, which causes a distortion of the true functional state of the tear system and makes it difficult to correctly interpret the results.

The closest analogue of the present invention is a method for the study of SOP, including the introduction of a contrast agent Omnipack in SOP with an iodine concentration of 300 mg / ml in dilution with distilled water in a ratio of 1: 1. All patients underwent a general dacryological examination, including an assessment of the position of the lacrimal openings, tubular test. Immediately before the administration of the contrast medium, probing of the lower lacrimal opening and washing of SOPs was performed. The contrast was installed in the conjunctival cavity in the amount of 1-2 drops per minute for 5 minutes, then computed tomography (CT) was done. In the case of inadequate visualization of SOPs, contrast was injected through the cannula and CT was performed (Helical computed tomographic dacryocystography and its role in the diagnosis and management of lacrimal drainage system blocks and medial canthal masses. Priti Udhay, Olma Veena Noronha, Ravindra E Mohan. Medical Research Foundation, Chennai, India, 2008).

However, the method has drawbacks, so dilution of Omnipack in distilled water in a ratio of 1: 1 reduces the visualization ability of the contrast medium, and the expansion of the lower lacrimal opening with a conical probe with washing of the SOP immediately before the study distorts the true functional state of the SOP.

The objective of the invention is to develop an improved functional method for the study of SOPs.

The technical result of the proposed method is the ability to adequately visualize the anatomical and functional features of SOPs throughout, determine the level and severity of obstruction of SOPs, determine its possible cause and choose further treatment tactics.

The technical result is achieved by washing the SOP a day before the study and performing DMSCT simultaneously with the administration of a Visipack contrast agent at a concentration of 320 mg / ml in SOP in a certain mode.

According to Blobel, N Sugihara (2007), the emergence in 2007 in the computed tomography system of the possibility of volume dynamic scanning allows diagnostics to be carried out at a new level. In the past, the assessment of the functional state of an organ was limited due to its small area of coverage. Today, using volume dynamic scanning (for example, a Toshiba Aquilion One computer tomograph, Japan), it is possible to study the functional state of the entire organ in less than 200 ms. The dynamic volumetric scanning system allows functional studies of the brain, heart, pancreas and other organs (J. Blobel et al. Fundamentals of image quality control in the dynamic volumetric CT system Toshiba Aquilion One, 2007).

Rossemodo in 1972 noted that a sharper and more contrasty image is obtained when using high contrast iodine radiopaque substances that dissolve in water and are used for intravascular injection. According to the author, these contrast agents should be introduced into SOP under slight pressure, creating conditions close to natural (Rossemodo N.M. A new method of evaluating lacrimal drainage. - Arch. Ophtal., 1972, 88, 5, p. 523 -525).

For research, we used Visipack, a water-soluble iodine-containing X-ray contrast substance that is close in properties to tear fluid. This radiopaque drug does not cause mucosal irritation and is well tolerated by patients. Vizipack is widely used in cardioangiography, cerebral angiography, peripheral arteriography, urography as a contrast enhancement. Unlike fat-soluble contrast agents used for diagnostics in dacryology, which tend to fragment in the lacrimal fluid, the water-soluble Visipack has a sparse consistency that allows not to expand additional SOP, which makes it possible to study in detail the phases of tear production. We used Visipack (Iodixanol) at a concentration of iodine of 320 mg / ml.

In order to comply with physiological conditions in SOPs, contrast was applied using an infusion B.Braun fmS (Germany), which provides infusion at a constant rate without creating increased pressure. The infusion regimen was developed by us. It is these modes that allow the introduction of a contrast medium with a constant speed and pressure. In order to avoid premature emptying of the SOP and to visualize the SOP along the entire length, the contrast medium and DMSC were performed simultaneously. For the possibility of further analysis of the obtained data on the anatomical and topographic features of SOPs, they perform multi-planar reconstruction (MPR) in coronary and oblique projections, as well as three-dimensional reconstructions, on which the anatomical and functional features of SOPs are studied throughout, phases of the tearing mechanism, determine the level, degree the severity and extent of stenosis, its possible cause.

The proposed method provides a clear visualization of the anatomical and functional features of SOPs throughout, determining the level, severity and extent of stenosis of SOPs, determining its possible cause and, accordingly, choosing further adequate treatment tactics.

The studies were conducted on a group of 10 volunteers and 20 patients with suspected SOP pathology.

Dynamic MSCT SOP with contrasting was performed on a Toshiba Aquilion one 320-spiral computer tomograph with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. Then, multi-planar and three-dimensional reconstructions were built, followed by analysis of the obtained data. A comparative analysis showed high information content of the proposed research method. Using DMSCT, it is possible to study the phases of the lacrimation mechanism, visualize the anatomical and functional features of SOPs throughout, determine the level, severity and extent of stenosis of SOPs, determine its possible cause and choose further treatment tactics.

The method is as follows: the patient undergoes, as is customary, a general ophthalmological and dacryological examination, “colored” tubular and nasal tests, anterior rhinoscopy, endoscopy of the nasal cavity. Diagnostic washing of SOPs is carried out a day before a dynamic CT scan. Dynamic MSCT is performed, for example, on a Toshiba Aquilion one 320-spiral computer tomograph with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. Patient laying - standard - lying on his back, his head is laid in a typical head restraint. To mark the research area, a topogram is performed. Topography begins from the lower edge of the upper jaw and ends at the level of the upper part of the frontal sinuses. Topographic Options:

- Mode - surround dynamic

- Slice thickness 0.5 mm

- Gantry tilt angle 0 °

- Field of study about 7 cm

- Voltage 80 kV

- Current 350 mA

- Type of reconstruction - bone.

After the topogram is completed, the first series of sections is carried out in axial projection. The course of scanning from the upper part of the frontal sinuses to the hard palate. At the same time, the introduction of a caustic substance into the SOP is simultaneously carried out. As a contrast, Visipack (Iodixaiol) is used - a non-ionic iodine-containing water-soluble X-ray contrast substance in an iodine concentration of 320 mg / ml. Contrast is introduced through the lower lacrimal openings into the lower lacrimal canaliculi of both eyes, using the silicone cannulas connected to an infusomatum. You can use the infusomat B. Braun fmS (Germany). Before carrying out the study on an infusomat, the infusion rate (400 ml / h), the infusion volume (5 ml) and the infusion time (2 min) are pre-established. Start the infusion mode and at the same time conduct MSCT with volumetric dynamic scanning with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. Then, reconstructed SOPs are reconstructed with an increase and reconstruction of a 0.5 mm slice. After obtaining sections in the axial projection, multi-planar reconstruction (MPR) is performed in the coronary and oblique projections, as well as three-dimensional reconstructions, on which the phases of the tearing mechanism are studied, the anatomical and functional features of the SOP are visualized along the entire length, the level, severity and extent of stenosis of the SOP are determined, determine its possible cause.

Example 1. Volunteer R., age: 43.

No complaints (taken from the norm group). I’m healthy. The day before the study, a general ophthalmological and dacryological examination was performed, “color” tubular and nasal tests, anterior rhinoscopy, endoscopy of the nasal cavity, and diagnostic washing. Dynamic MSCT with contrasting SOPs was performed on a Toshiba Aquilion one 320-helical computer tomograph with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. The vessel was filled with a contrast medium (Visipack) with a volume of about 0.5 liters. The contrast medium entered the patient’s lacrimal canaliculi and then into the SOP via silicone cannulas connected to an infusomat, for example, B. Braun fMS (Germany), which provided pumping of the fluid at a constant flow rate. The desired infusion rate (400 ml / hr), infusion volume (5 ml) and infusion time (2 min) were pre-set on the infusomat. Silicone cannulas were introduced to the patient in the tear ducts of the right and left eyes. We started the infusion mode and simultaneously performed multispiral computed tomography with volume dynamic scanning with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. Then built multi-planar and three-dimensional reconstruction. According to the results of DMSCT, no pathological changes were detected (Figs. 1-6 - oblique projection, where: 1 - SOP OS without contrast medium, 2 - contrast in the region of the lower lacrimal tubule of the OS, 3 - contrast in the region of the upper lacrimal tubule of the OS, 4 - contrast at the mouth of the lacrimal canaliculi OS, 5 - contrast in the body area of the lacrimal sac OS, 6 - contrast in the neck of the lacrimal sac OS, 7 - contrast in the upper third of the nasolacrimal duct OS, 8 - contrast in the middle third of the nasolacrimal duct OS, 9 - contrast in the region of the lower third of the nasolacrimal duct OS, 10 - contrast output that in the nasal cavity on the left).

Example 2. Patient S., 65 years old.

Complains of lacrimation and lacrimation of the right eye in the street and indoors. From the left eye, no complaints. Preliminary diagnosis: OD - dacryostenosis, OS - normal. In order to determine the level, degree and extent of stenosis on the right, to study the functional state of SOP on the left, DMSCT SOP with contrast was recommended. The day before the study, a general ophthalmological and dacryological examination was performed, “color” tubular and nasal tests, anterior rhinoscopy, endoscopy of the nasal cavity, and diagnostic washing. The results of the tubular test: OD = 15 minutes, OS = 3 minutes, nasal test on the right is 19 minutes, on the left - 5 minutes. Anterior rhinoscopy and endoscopy of the nasal cavity without features corresponds to the age norm. During diagnostic flushing, the flushing fluid flows out of the nose with a thin stream at moderate pressure on the piston, and on the left with a plentiful stream with light pressure on the piston. Dynamic MSCT SOP with congrading was performed on a Toshiba Aquilion one 320-spiral computer tomograph with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. The vessel was filled with a contrast medium (Visipack) with a volume of about 0.5 liters. The contrast medium was delivered to the patient’s lacrimal canaliculi and then to the lacrimal passages through silicone cannulas connected to an infusomat, for example, B. Braun fMS (Germany), which provided a constant flow rate of fluid pumping. The desired infusion rate (400 ml / hr), infusion volume (5 ml) and infusion time (2 min) were pre-set on the infusomat. Silicone cannulas were introduced to the patient in the tear ducts of the right and left eyes. We started the infusion mode and simultaneously performed multispiral computed tomography with volume dynamic scanning with a slice thickness of 0.5 mm and an interval of 0.25 mm in axial projection. Then built multi-planar and three-dimensional reconstruction. According to the results of MSCT - narrowing in the neck of the lacrimal sac and at the exit into the nasal cavity on the right, on the left - normal CT - picture of the tear ducts. Figa (coronary projection), figb (sagittal projection), where: 1 - contrast in the area of the mouth of the lacrimal tubules OD; figa (coronary projection), fig.2b (sagittal projection), where: 2 - the body of the lacrimal sac OD, 3 - the contrast in the neck of the lacrimal sac OD; figa (coronary projection), fig.3b (sagittal projection), where: 4 - contrast in the area of the nasolacrimal duct on the right. According to the obtained tomograms, moderate stenosis on the right at the level of the neck of the lacrimal sac and at the exit into the nasal cavity on the right, CT scan on the left - a picture of normal SOPs. Based on the data obtained, a diagnosis was made - dacryostenosis on the right, on the left - the norm. Treatment was prescribed in the form of a course of washing the lacrimal passages OD with Collalizine N8 solution.

Thus, the proposed method allows you to visualize the movement of the contrast medium along the SOP throughout. In this regard, it becomes possible to study the phases of the lacrimation in the norm and in the pathology of the lacrimal system. The particular value of using DMSCT lies in the possibility of determining not only the level of stenosis of SOPs, but also the degree and extent of stsosis, which in turn allows us to determine further treatment tactics with great accuracy.

Claims (1)

A method for examining a lacrimal system, including washing the lacrimal passages and introducing a contrast medium into the lacrimal ducts, characterized in that the lacrimal ducts are washed the day before the study, and Visipack at a concentration of 320 mg / ml is used as a contrast medium, it is administered through the infusion system at a rate infusion of 400 ml / h, infusion volume of 5 ml, infusion time of 2 min, simultaneously conduct multispiral computed tomography with volume dynamic scanning with a slice thickness of 0.5 mm and an interval of 0.25 mm axial projection and build multi-planar and three-dimensional reconstruction.

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