Sialografiya

Sialography (radiography of salivary glands with artificial contrast of their ducts) is most often used to diagnose various diseases.

Sialografiya allows you to judge the condition of the ducts and the parenchyma of the gland.

[1], [2]

Methods of carrying out the sialography

Sialografiya is to study the ducts of large salivary glands by filling them with iodine-containing drugs. To this end, use water-soluble contrast or emulsified oil preparations (dianosyl, ultra-liquid lipoiodinol, etiyldol, mayodil, etc.). Before administration, the preparations are heated to a temperature of 37-40 ° C to exclude cold vasospasm.

The study is conducted to diagnose mainly inflammatory diseases of the salivary glands and saliva-stone disease.

A special cannula, a thin polyethylene or non-latonic catheter with a diameter of 0.6-0.9 mm or a blunt and slightly curved injection needle is inserted into the opening of the excretory duct of the salivary gland examined. After the flowering of the duct, the catheter with the mandrel inserted into it at a depth of 2-3 cm is tightly covered by the duct walls. To study the parotid gland, 2-2.5 ml is administered, the submandibular gland is administered with 1-1.5 ml of a contrast agent.

Radiography is performed in standard lateral and direct projections, sometimes performing axial and tangential shots.

With simultaneous contrasting of several salivary glands, panoramic tomography (pantomosialografy) is preferred, which allows one to obtain a rather informative picture in one picture at low radiation loads on the patient.

Analysis of the pictures taken in 15-30 minutes, makes it possible to judge the function of the salivary glands. To stimulate salivation, citric acid is used.

Sialografiya in conjunction with CT is successfully used for the distinctive recognition of benign and malignant tumors of the parotid salivary gland.

In recent years, ultrasound has been used to diagnose salivary gland diseases, a functional digital subtraction sialogram. The introduction of contrast agents into cystic formations is carried out by puncturing the wall of the cyst. After suctioning the contents, a heated contrast medium is introduced into the cavity. Radiographs are performed in two mutually perpendicular projections.

As a contrast agent, use oil (iodolipol, lipiodol, etc.) or water-soluble (76% solution of veropain, 60% urographine solution, omnipac, trazograph, etc.) preparations. Water-soluble drugs are advisable to apply to cases of risk of getting the substance outside the salivary gland (in patients with Sjogren's syndrome, with strictures of the ducts, malignant tumors) and in contraindications to long-term retention of iodine preparations in the ducts (in patients undergoing radiotherapy). Contrast substance is slowly introduced through the duct into the gland until the patient feels a sense of bursting in it, which corresponds to the filling of channels of I-III orders. To fill the ducts of unchanged parotid gland, 1-2 ml of oily or 3-4 ml of water-soluble preparation is required. To fill the ducts under the mandibular gland - respectively 1.0-1.5 ml and 2.0 - 3.0 ml.

The sialogram of salivary glands is carried out only during remission of the process. Otherwise the aggravation of the course of sialadenitis may follow.

The most complete picture of the structure of the parotid gland is obtained on the sialogram in the lateral projection. In the sialogram of the submaxillary glands in the lateral projection, the submandibular duct is determined at the level of the body of the lower jaw, the upper pole is superimposed on the angle of the lower jaw, the greater part being defined below its base.

Pantomosialography

This is a sialogram with simultaneous contrasting of two parotid, two submandibular or all four salivary glands followed by panoramic tomography. This technique is shown in the same cases as the sialogram. Simultaneous examination of the paired glands allows revealing a clinically hidden inflammatory process in the paired gland.

The description of the sialogram is made according to the following scheme. With respect to the parenchyma, the gland is established:

• how the image is revealed (well, fuzzy, but evenly, unclearly and unevenly, not detected);
• presence of a defect in filling the ducts;
• the presence of cavities of different diameters;
• clarity of contours of cavities.

When examining the ducts, determine:

• narrowing or widening of IV channels (uniform, uneven);
• expansion of the parotid or submandibular duct (uniform, uneven);
• mixing or discontinuity of the ducts;
• clarity of the contours of the ducts (clear, fuzzy).

Digital sialography

This sialografiya, which is carried out on special devices (usually with digital information), allows you to get a more contrast image and analyze it in the dynamics of filling the gland and evacuating the contrast medium.

Digital subtractional sialography increases the diagnostic capabilities of sialography due to subtraction (subtraction of the surrounding background of bone-tissue formations) and the ability to visualize the filling and evacuation of contrast medium in the dynamics of the study. The examination is performed on X-ray machines with a digital prefix or on angiographs; the time of examination is 30-40 seconds. An analysis of the flow system pattern, the time of filling and evacuation of the water-soluble contrast medium is performed.

[3], [4], [5]

Sialadenolymphography

The method was suggested by V.V. Neustroiev et al. (1984) and Yu.M. Kharitonov (1989) for the diagnosis of salivary gland diseases based on the study of their lymphatic apparatus (intra- and extraorganic lymphatic system). Using a syringe and a needle in the parotid gland, 4 ml of a water-soluble or 2 ml of a fat-soluble contrast medium is transdermally administered. After 5 and 20 minutes, 2 and 24 hours make serial sialadenolymphography. The authors pointed out that the X-ray semeiotic of chronic sialadenitis is associated with an uneven depletion pattern of intraglacial lymph vessels with preservation of the contours of the organ and regional lymph drainage. For tumors, the filling defect is determined.

Computer sialotomography

The image is obtained on computer tomographs. Scanning starts from the level of the hyoid bone at a Gentry tilt of 5 ° for submandibular and 20 ° for the parotid glands. Perform 15 slices with a pitch (thickness) of 2-5 mm. The resulting cross-section is a topographic anatomical, similar to Pirogov's. The method is indicated for the diagnosis of salivary stone disease and various types of salivary gland tumors.

Radionuclide research methods (radiosialography, scanning and scintigraphy) are based on the selective ability of the glandular tissue to absorb radioactive isotopes I-131 or Technetium-99m (pertechnetate). These methods are practically harmless, since the patient is injected with indicator doses of radiopharmaceutical with a radiation power of 20-30 times less than in a conventional radiographic study. The methods allow to objectively assess the functional state of the secreting parenchyma, regardless of the quality and quantity of secretion, to carry out differential diagnosis between the tumor and inflammation of the salivary gland.

Radiosialography of the parotid glands (radioisotope sialometry) was developed by L.A. Yudin. The study consists of recording the radiation intensity curves for the parotid glands and heart after intravenous administration of pertechnetate (Tc-99m) at a dose of 7.4-11.1 MBq and allows an objective evaluation of their function. The radiosialogram of unchanged parotid glands normally consists of three curves: the first minute there is a sharp rise in radioactivity over the salivary glands, then a small rapid decline (the first vascular segment of the curve). Further, for 20 minutes, the radioactivity gradually increases. This section is called the concentration segment. The increase in radioactivity stops or goes less intensively (plateau). This level of radioactivity corresponds to the maximum accumulation of radiopharmaceutical (MPH). Normally, the MPR time is 22 ± 1 min for the right and 23 + 1 min for the left WSUS. After 30 minutes, stimulation of saliva by sugar leads to a sharp (within 3-5 min) fall in radioactivity, and this site is called the excretory segment. In this period, determine the percentage and time of the maximum fall in radioactivity. Normally, the percentage of MNR is 35 ± 1 for the right and 33 + 1 for the left WSUS. Time MPR is 4 + 1 min for the right and left parotid glands. The next segment of the curve is called the second concentration segment. In addition, it is possible to determine the ratio of radioactivity in the salivary gland at the conditional time intervals (3, 10, 15, 30, 45 and 60 min) and the MNR moment to the radioactivity of the blood at the 30th minute (if necessary to obtain quantitative parameters of radioactivity in the gland in the indicated time periods). In diseases of the salivary glands, all parameters change. The method of radiosialography allows the most accurate determination of the functional state of the parotid salivary glands.

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Sialosanography (ultrasound diagnosis of salivary gland diseases)

The method is based on different degrees of absorption and reflection of ultrasound by the tissues of the salivary gland with different acoustic resistance. Sialosonography gives an idea of the macrostructure of the salivary gland. According to the echogram, it is possible to judge the magnitude, shape and ratio of the layers of the gland with various densities, to identify sclerotic changes, salivary stones and the boundaries of neoplasms.

Thermosialography (thermovision, thermal imaging)

Allows you to observe the dynamics of temperature changes in the salivary glands. The method is based on different degrees of infrared radiation of tissues with different morphological structure, as well as on the possibility of measuring the temperature of the studied object at a distance and observing its distribution over the surface of the body in dynamics. For thermovision, thermal imagers are used, on the kinescope of which a thermal map of the temperature of the face and neck is created. It has been established that there are normally three types of symmetrical thermo-picture of the face: cold, intermediate and hot, which are individual for each person and persist throughout life. Inflammatory processes and malignant tumors of the salivary glands are accompanied by an increase in the skin temperature above them in comparison with the opposite, healthy side, which is recorded by the thermal imager. With the help of the method, it is also possible to determine the secretively occuring inflammatory processes in the salivary glands. The method is simple, harmless and has no contraindications.

Such methods as sialotomography (combination of conventional nomography and sialotrafy), electrorentgenosialigraphy (sialography using an electroradiographic device and obtaining sialograms on writing paper), pneumosubmandibulography (sialogram of the submandibular salivary gland with simultaneous filling of the soft tissues of the submandibular region with oxygen), stereoradiography (spatial, volumetric X-ray image of the ducts of the salivary glands with the help of two X-ray photographs taken under different angles to the X-ray tube), sialography with a direct magnification of the image, are currently used rarely and mainly in the conduct of scientific research.

Rheography of salivary glands is carried out for the study of vascular blood flow and microcirculation in tissues with various forms of chronic sialadenitis. Changes in the nature of the amplitude of fluctuations and the rate of blood flow make it possible to assess the degree of morphological changes and predict the course of the disease. Associated diseases can be reflected in the results of the study, and therefore should be taken into account when assessing them.

X-ray diagnosis of salivary gland diseases

Large salivary glands (parotid, submandibular,  sublingual ) have a complex tubular-alveolar structure: they consist of parenchyma and IV-order ducts (respectively, interlobar, interlobular, intralobular, intercalary, striated).

Parotid gland. Its growth and formation take place up to 2 years. The size of the gland in an adult: vertical 4-6 cm, sagittal 3-5 cm, transverse 2-3.8 cm. The length of the parotid (stenoval) duct 40-70 mm, diameter 3-5 mm. In most cases, the duct has an ascending direction (obliquely posteriorly anteriorly and upward), sometimes descending, less often its shape is straight geniculate, arched or bifurcated. The form of the gland is incorrectly pyramidal, trapezoid, sometimes semilunar, triangular or oval.

For the purpose of examining the parotid gland, radiographs are performed in the frontal-nasal and lateral projections. In the fronto-nasal projection, the gland branches project outside of the lower jaw, and in the lateral they overlap the branch of the lower jaw and the submandibular fossa. Exiting the gland at the level of the anterior edge of the branch, the duct opens on the threshold of the oral cavity in accordance with the crown of the second upper molar. On the fronto-nasal radiographs, the projection shortens the duct. The optimal conditions for studying the duct are created on orthopantomograms.

The submandibular salivary gland has a flattened-rounded, ovate or ellipsoidal shape, its length is 3-4.5 cm, width 1.5-2.5 cm, thickness 1.2-2 cm. The main submandibular (varton) excretory duct has a length of 40 -60 mm, width 2-3 mm, in the mouth up to 1 mm; as a rule, it is straight, more rarely arched, opens on either side of the frenum of the tongue.

The dimensions of the sublingual salivary gland 3.5x1.5 cm. The sublingual (Bartholin) excretory duct has a length of 20 mm, a width of 3-4 mm, opens on both sides of the frenum of the tongue.

In connection with anatomical features (a narrow duct opens in several places of the hyoid fold or in the submandibular duct), it is not possible to produce a sublingual gland sialogram.

Involutional changes in large salivary glands are manifested by a decrease in the size of the glands, lengthening and narrowing of the lumen of the ducts take place, they acquire a segmental,

Depending on the etiology and pathogenesis, the following diseases of the salivary glands are distinguished:

1. inflammatory;
2. reactive-dystrophic sialosis;
3. traumatic;
4. tumor and tumor-like.

Inflammation of the salivary gland manifests itself in the form of inflammatory diseases of the duct of the salivary gland, and has been called "sialodohitis", the parenchyma of the gland is "sialadenite." Infection of the parenchyma of the salivary glands occurs through the ducts from the oral cavity or hematogenously.

Acute inflammation of the salivary gland is a relative contraindication to carrying out the sialogram, since it is possible to retrograde infection with the administration of a contrast agent. The diagnosis is established on the basis of a clinical picture of the results of serological and cytological studies of saliva.

Chronic nonspecific symptoms of inflammation of the salivary glands are divided into interstitial and parenchymal.

Depending on the severity of changes in iron on sialograms, three stages of the process are distinguished: initial, clinically pronounced and late.

X-ray methods include non-contrast radiography in various projections, sialogram, pneumosubmandibulography, computed tomography and combinations thereof.

Chronic parenchymal sialadenitis affects primarily the parotid gland. In these cases, lymphohistiocytic infiltration of the stroma is observed, in places there is a desolation of the ducts in combination with their cystic enlargement.

In the initial stage, on the sialogram, rounded clusters of contrast medium 1-2 mm in diameter are detected against the background of unchanged parenchyma and ducts.

In the clinically pronounced stage, the channels of II-IV orders are sharply narrowed, their contours are even and clear; the gland is enlarged, the parenchyma density is reduced, a large number of cavities with a diameter of 2-3 mm appear.

In the late stage, abscesses and scarring occur in the parenchyma. Numerous different sizes and shapes (mostly rounded and oval) are seen in the cavities of abscesses (diameter from 1 to 10 mm). Protocols IV and V orders on the sialogram are narrowed, in some areas there are none. Oil contrast medium is retained in cavities up to 5-7 months.

In chronic interstitial sialadenitis, stroma proliferation, hyalinization with substitution and compression of the parenchyma and ducts with fibrous tissue are noted. Primarily affected parotid glands, less often - submandibular.

At the initial stage of the process, the narrowing of the HI-V channels is revealed and some unevenness in the image of the parenchyma of the gland.

In the clinically pronounced stage, the ducts of II-IV orders are considerably narrowed, the density of the parenchyma is reduced, the gland is enlarged, the contours of the ducts are even, clear.

In the late stage, all ducts, including the main one, are narrowed, their outlines are uneven, in some areas they are not contrasted.

Diagnosis of specific chronic sialadenitis (for tuberculosis, actinomycosis, syphilis ) is established taking into account serological and histological studies (detection of drusen with actinomycosis, mycobacteria in tuberculosis). In patients with tuberculosis, the detection on the roentgenogram of calcifications in the gland has an important diagnostic value. The sialogram shows multiple cavities filled with contrast medium.

Chronic sialodohitis. Primarily parietal gland ducts are affected.

In the initial stage on the sialogram the main excretory duct is unevenly expanded or unchanged, the ducts I-II, sometimes II-IV orders, are widened. The extended sections of the ducts alternate with the unaltered (view of the rosaries).

In the clinically pronounced stage, the lumen of the ducts is significantly expanded, their outlines are uneven, but clear. The expansion sites alternate with the sites of constriction.

In the late stage on the sialogram, the areas of expansion and narrowing of the ducts alternate; sometimes the course of the ducts is interrupted.

Saliva-stone disease (sialolithiasis)  is a chronic inflammation of the salivary gland, in which concretions (salivary stones) form in the ducts. The most often affected submandibular, less often - parotid and extremely rarely - the hyoid gland. The share of salivary stone disease accounts for about 50% of all cases of salivary gland diseases.

One or several stones are located mainly in the areas of the main duct bending, their mass varies from several grams to several tens of grams. They are localized in the submandibular salivary gland.

Diagnosis is established after X-ray or ultrasound. Stones can be located in the main excretory duct or in ducts of I-III orders (they are commonly called "gland stones"). The stones are calcified in most cases and are determined on the roentgenogram in the form of clearly defined dense shadows of round or irregularly oval shape. The intensity of the shadow is variable, determined by the chemical composition and magnitude of the stones. To diagnose the stones of the varton duct of the submandibular salivary gland, intraoral roentgenography of the oral cavity bottom is applied, and if the "stones of the gland" is suspected, the x-ray of the lower jaw is in the lateral projection. Radiographs of the parotid salivary gland produce X-rays of the lower jaw in the lateral projection and images in the frontal-nasal projection.

In order to identify unimagined (X-ray negative) stones and assess the changes in the salivary gland, sialography with the use of water-soluble drugs is of particular importance. On sialograms stones have the appearance of a filling defect. Sometimes they are enveloped, impregnated with contrast material and become visible in the picture.

In the initial stage, the expansion of all ducts located behind the calculus (salivary retention stage) is determined on the sialogram.

In the clinically pronounced stage, the areas of expansion and narrowing of the ducts alternate.

In the late stage, as a result of repeated exacerbations, cicatricial changes occur, leading to the formation of filling defects. The contours of the gland ducts are uneven.

X-rays detect stones 2 mm or more in size, the stones located in the gland are better seen.

The group of reactive-dystrophic processes includes Sjogren's disease and Mikulich's disease.

Disease and Sjogren's syndrome. The disease manifests itself by the progressive atrophy of the parenchyma of the salivary glands with the development of fibrous connective tissue and lymphoid infiltration.

In the initial stage of the disease there are no changes on the sialogram. In the future, extravasates appear due to increased permeability of the duct walls. In later stages, cavities of round and oval form with a diameter of up to 1 mm, and III-V orders appear unfilled. As the disease progresses, the cavities increase, their contours become indistinct, the ducts are not filled, the main duct is enlarged. In general, the sialogram picture is the same as in chronic parenchymal sialadenitis.

Disease of Mikulich. The disease is accompanied by lymphoid infiltration or the development of granulation tissue on the background of a chronic inflammatory process.

On the sialogram the main duct of the salivary gland is narrowed. Lymphoid tissue, squeezing the ducts in the lobes of the lobes, makes it impossible to fill the smallest channels with contrast material.

Benign in malignant formation of the salivary glands. On sialograms in malignant tumors due to their infiltrative growth, the border between normal tissue and tumor is fuzzy, respectively, the tumor shows a filling defect. In benign tumors, a filling defect with clear contours is determined. Filling the ducts in the peripheral parts of the tumor suggests a benign character of the process. Diagnostic possibilities are extended by combining sialography with computed tomography.

If a malignant tumor is suspected, it is preferable to perform the sialogram using water-soluble contrast agents, which are secreted and dissolve faster than the oil ones. This is important, as in some patients radiation therapy is planned in the future.