Ultrasound signs of uterine pathology

Pathology of myometrium

Currently, given the widespread introduction into clinical practice of transvaginal ultrasound, the diagnosis of pathological changes in the myometrium does not present significant difficulties. However, the informativity of ultrasonic diagnostics for different pathologies of the myometrium is not the same.

Ultrasound scanning is the most informative method for diagnosing uterine fibroids. Transabdominal ultrasound before hysteroscopy serves to determine the location and magnitude of myomatous nodes. However, only the high resolution of transvaginal sensors allows a more detailed study of the size, location and structure of myomatous nodes, to identify nodes of very small size, especially in patients with obesity. Yielding only to laparoscopy and hysteroscopy for subserous and submucous localization of myomatous nodes, respectively, transvaginal scanning is the leading method for diagnosing intermuscular nodes. The accuracy of determining submucous and interstitial nodes with a centripetal (toward the uterine cavity) growth is 95.7%.

Ultrasound criteria for uterine fibroids: an increase in the size and contours of the uterus, the appearance in the myometrium or uterine cavity of structures of round shape with increased acoustic conductivity.

There are acoustic criteria for the dystrophic transformation of the myomatous nodes of the uterus, which are detected in transabdominal ultrasound:

1. Areas of increased echogenicity without clear boundaries.
2. Anechogenous cystic inclusions.
3. The phenomenon of acoustic amplification along the periphery of a node.

A.N. Strizhakov and A.I. Davydov (1997) during transvaginal ultrasound reveals histologically verified ultrasound signs of proliferating uterine fibroids: the presence of echo-negative areas in combination with fragments of the tumor of average echogenicity. According to the authors, depending on the degree of expression of proliferative processes, the ratio of cystic and dense components of myoma varies.

With ultrasound diagnosis of submucosal or intermuscular uterine fibroids with centripetal growth, special attention should be paid to the state of the mid-uterine structure (degree of deformation of the M-echo). In ultrasound, submucosal nodes of myoma are visualized in the form of rounded or ovoid formations with smooth contours and medium echogenicity located in the enlarged uterine cavity. As a rule, the shape of the uterus cavity is changed only by submucous nodes of large size. With a small tumor size, only the anteroposterior size of the M-echo is noted.

With the centripetal growth of the interstitial node, a deformed uterine cavity with smooth contours (regardless of the size of the node) is always determined. In this case, acoustic signs of fibroid are visualized both near the concave surface of the uterine cavity and the M-echo, and in the adjacent myometrium.

Given that the accuracy of diagnosis under the mucosa and intermuscular myoma of the uterus with centripetal growth increases against the background of uterine bleeding (accumulated in the uterine cavity blood plays a kind of natural contrast), in recent years, with this pathology is widely used hydro sonography. The introduction of a contrast agent into the uterine cavity allows a more precise determination of the size of the formation, the spatial ratio of the tumor to the walls of the uterine cavity and the severity of the intermuscular component of the myomatous node.

Intrauterine ultrasound

The accuracy of ultrasound diagnosis of submucous uterine fibroids in the future will significantly increase when introducing intrauterine ultrasound. It is carried out with the help of special sensors with an enlarged uterine cavity, which is especially important, since the conditions of the method are as close as possible to those for transcervical resection of myoma nodes. This method even before the operation can give the most valuable information about the magnitude of the intramural component of the submucosal node.

More objective information for uterine myoma can be obtained with the help of three-dimensional ultrasound, which is increasingly used in gynecology.

To assess peripheral hemodynamics in patients with uterine myoma and the degree of vascularization of myomatous nodes, Doppler examination and color Doppler mapping are used. With uterine myoma, a significant reduction in vascular resistance in uterine arteries has been demonstrated, which indicates an increase in the arterial blood flow. Decrease in the index of resistance in the vessels of the myomatous node is characteristic for its necrosis, secondary degeneration and inflammatory processes. Color Doppler mapping allows detecting myomatous nodes with pronounced vascularization, which, according to Friedman et al. (1987), correlates with the effectiveness of therapy with gonadotropin-releasing hormone analogues (GnRH).

In the diagnosis of adenomyosis in recent years, great importance is attached to highly informative instrumental methods of investigation, including ultrasound scanning. In this case only transvaginal ultrasound allows to diagnose with a high degree of accuracy the defeat of the endometriosis of the muscular membrane of the uterus.

Pathognomonic acoustic criteria of internal endometriosis were developed: uterine enlargement (mainly due to anteroposterior size) with asymmetric thickening of the anterior and posterior walls, rounded uterine shape, the appearance of abnormal cystic cavities in myometrium, heterogeneity of the echogenic structure of the myometrium, fuzzy boundary between the endometrium and myometrium, etc. . However, according to various authors, the accuracy of adenomyosis diagnosis using transvaginal ultrasound does not exceed 62-86%. This is due to the fact that even with transvaginal adenomyosis, it is not always possible to distinguish endometrioid cavities in myometrium from false echoes (for example, dilated vessels with chronic endometriometry), an increase in the anteroposterior size of the uterus with adenomyosis from that in other pathological conditions of the uterus (for example, in myomas uterus), etc. It should be emphasized that the detection of true endometrioid cavities (cystic cavities of irregular shape, surrounded by a thin echopositive line) becomes possible, as a rule, only at II-III degree of prevalence of the pathological process according to the classification of B.I. Zheleznova and A.N. Strizhakova (1985).

Less difficult is the diagnosis of the nodal form of the disease. The use of high-frequency transvaginal sensors allows for a clear differentiation of the nodes of adenomyosis and uterine myoma. The main acoustic criterion of nodes of adenomyosis is the absence of the surrounding connective tissue capsule, which is characteristic for interstitial uterine myoma.

Helps in the differential diagnosis of the nodular form of adenomyosis and uterine fibroids of small sizes. Color Doppler mapping: nodes of adenomyosis are visualized more clearly and brightly than myomatous, for which, in contrast to adenomyosis, there is a surrounding bright color rim representing the reflection of an ultrasonic wave from a connective tissue capsule.

Pathology of the endometrium

The ultrasonic picture of the endometrial polyps depends on their number, size, location and shape. Polyps are visualized inside the enlarged uterine cavity in the form of rounded or ovoid formations of formations, which usually have even outlines. In contrast to submucous myomatous nodules, lower echogenicity is characteristic of endometrial polyps. As a rule, they do not change the shape of the uterus (with the exception of large polyps).

Endometrial polyps are easier to diagnose with uterine bleeding, in which case the polyp is well contrasted and clearly visible, as it does not merge with the walls of the uterus and the endometrium.

Significantly facilitates the diagnosis of endometrial polyps using a contrast medium when carrying a transvaginal ultrasound. The accumulated experience of carrying out hydrosonography testifies to the high informativeness of this method in the differential diagnosis of various types of intrauterine pathology. Endometrial polyps clearly protrude against the background of contrast fluid.

The most accurate methods for diagnosing hyperplastic processes and endometrial cancer are hysteroscopy and a histological examination of the scraping of the mucous membrane of the uterine cavity. However, given the high information content and minimal invasiveness of transvaginal ultrasound, it is assigned an important role both in the mass examination of women (especially in postmenopausal and hormone replacement therapy) and in the differential diagnosis of various pathological conditions of the uterine mucosa accompanied by uterine bleeding.

Diagnosis of endometrial hyperplasia in ultrasound is based on the detection of a median M-echo increased in anteroposterior size with increased acoustic density. The structure of hyperplastic endometrium may be either homogeneous or with echo-negative inclusions (it is difficult to distinguish from endometrial polyps). A second type of endometrial hyperplasia is also described, in which the hyperechoic gene thickened, thickened endometrial contours limit the hypoechoic homogeneous zone on the echogram.

Transvaginal ultrasound is of great importance in the examination of patients in postmenopausal women with the goal of preventing malignant transformation of the endometrium. According to numerous studies, a risk group among postmenopausal women is women who, with ultrasound, are noted to increase the anteroposterior size of the median uterine structure with an increase in echogenicity.

To date, clear criteria for endometrial pathology in asymptomatic patients in postmenopausal women have not been established; according to different authors, the upper limit of the thickness of the endometrium varies from 5 to 10 mm. At the same time, in the presence of any symptomatology in postmenopausal women, the endometrial thickness is considered to be a thickness of 4 mm or more. On the other hand, the authors believe that a very thin, incalculable endometrial ultrasound, also characteristic of postmenopausal patients, does not exclude the pathology of the endometrium. The accumulation of fluid in the uterine cavity, which is determined by repeated ultrasound, should be alarming; In this case, additional invasive diagnostics are necessary. According to Timmerman and Vergote (1997), provided that all patients with this boundary thickness of the endometrium will undergo additional invasive diagnostics (hysteroscopy, separate diagnostic curettage), the number of surgical interventions can be reduced by 50%.

Endometrial cancer

The possibilities of ultrasound diagnosis of endometrial cancer are limited, since, according to most researchers, malignant transformation of the endometrium does not have specific echographic features. The promising studies on the application of color Doppler mapping in the diagnosis of endometrial cancer have not been well confirmed. To increase the diagnostic capabilities of transvaginal ultrasound for the purpose of differential diagnosis between the polyp, myomatous node and the thickening of the endometrium (hyperplasia or cancer), hydrosonography is recommended.

It is believed that, in contrast to transabdominal ultrasound, a transvaginal study can be used to determine the stage of the disease based on the depth of the myometrium invasion:

• Stage Ia - there are no ultrasound signs of myometrium invasion.
• Stage Ic - invasion of the myometrium by more than 50%. The diameter of the endometrial echoes is more than 50% of the anteroposterior size of the uterus.
• Stage II - the tumor extends to the cervix. There is no clear demarcation line between the endometrial echoes and the cervical canal.

It should be emphasized that the main role assigned to transvaginal ultrasound in identifying endometrial cancer is the screening of high-risk patients: postmenopausal women who have a history of family history of breast, ovarian, and uterus cancer. When an endometrial thickening or unclear ultrasound pattern is detected, invasive diagnosis is performed. A special group of high-risk women are postmenopausal women with breast cancer who are taking tamoxifen. It is proved that they often have endometrial hyperplasia, polyps and endometrial cancer.

[1], [2], [3], [4], [5], [6]

Complications of pregnancy

Ultrasound allows early detection of most complications at their preclinical stage. In the presence of symptoms of the disease, ultrasound gives the opportunity to choose the optimal treatment tactics in due time and determine the indications for hysteroscopy.

One of the most common complications of the first trimester of pregnancy is the termination of pregnancy. The different stages of abortion flow have a characteristic echographic pattern.

The ultrasound picture of incomplete abortion depends on the period of pregnancy and the number of parts of the fetal egg released from the uterus. The size of the uterus with incomplete abortion is less than the expected duration of pregnancy. In the uterine cavity, a large number of separate disparate structures of irregular shape with different echogenicity are revealed, the fetal egg has a flattened shape. The echogram often resembles an ultrasound image of an undeveloped pregnancy or the initial form of a bladder drift. With complete abortion, the uterine cavity, as a rule, is not dilated, the endometrium is relatively thin and uniform.

The most frequent ultrasound picture of an undeveloped pregnancy is anembrion, or an empty fetal egg, i.e. Absence of an embryo in the cavity of the fetal egg, measuring more than 24 mm in transabdominal and more than 16 mm with transvaginal ultrasound. Despite the absence of an embryo, the size of the fetal egg and uterus can increase until the 10th to 12th week of pregnancy, after which their growth usually stops and the clinical symptoms of a miscarriage begin. Studies Kurjak et al. (1991), it is shown that in some cases color Doppler mapping shows vascularization of empty fetal eggs, the degree of which depends on the trophoblast activity. The authors believe that by the severity of vascularization, it is possible to predict in which cases in this pathology there is a risk of a bubble drift.

The diagnosis of an undeveloped pregnancy with ultrasound is also set in the absence of cardiac contractions in an embryo whose length exceeds 6 mm. With this pathology, color Doppler mapping is of great help. With the recent death of the fetus, the fetal egg and embryo have the usual shape and size, there may be no clinical signs of a threat of termination of pregnancy. With a longer stay of the deceased embryo in the uterus, ultrasound reveals abrupt changes in the structure of the fetal egg, visualization of the embryo is usually not possible.

Ultrasound is the most accurate method for diagnosing bladder drift. In this case, the diagnosis is based on the detection of multiple echoes in the uterine cavity, creating a picture of a "snow storm". The longer the gestation period, the more accurate the diagnosis, which is associated with the increase in the size of the bubbles (the picture becomes more distinct).

Also, there is no difficulty in ultrasound diagnosis of partial gall bladder during pregnancy for more than 12 weeks, if the fetus develops normally. With small changes in the chorion and / or severe degeneration of the fetus, the detection of this pathology is often difficult. Differential diagnosis should be performed with uterine myoma during secondary changes in myomatous nodes (edema, necrosis). Difficulties can be encountered in the differential diagnosis of bladder skipping with an undeveloped pregnancy with significant regressive changes.

The ultrasonic criterion for invasion of trophoblast during transvaginal ultrasound is the appearance of focal echogenic sites in myometrium, which may be surrounded by an even more echogenic tissue of the trophoblast.

Valuable information in the diagnosis of trophoblastic disease (invasive bladder skid and chorion carcinoma) gives a transvaginal color Doppler study. Detection of areas of increased vascularization in myometrium (enlarged spiral arteries and newly formed vessels feeding the tumor) with the help of color Dopplerography allows to diagnose this pathology at an earlier time. At the same time, uteroplacental vessels reflect ultrasound worse than in normal pregnancy. Color dopplerography also helps in the differential diagnosis of gestational trophoblastic disease with the remains of the fetal egg after abortion and the pathology of the endometrium.

[7], [8], [9], [10],

Malformations of the uterus

It is extremely important to identify the developmental defects of the uterus before performing hysteroscopy. Echographic diagnosis of malformations of the uterus presents certain difficulties, and the informative nature of this method in revealing this or that pathology is not great.

Diagnosis of the two-horned uterus and its doubling with ultrasound is not difficult. The transverse size of the uterus predominates over the longitudinal, on the echogram there are seen as two separate uterus, connected in the region of the isthmus or somewhat higher; sometimes it is possible to visualize two M-echoes.

The septum in the uterine cavity is not always visible, it is defined on the echogram as a thin-walled structure going in the anteroposterior direction; It seems that the uterus consists of two parts. According to S. Valdes et al. (1984), it is impossible to distinguish between a bicornic uterus and a full or incomplete septum in the uterine cavity. At the same time, Fedele et al. (1991) describe the differential echographic features of these malformations of the uterus for determining the tactics of surgical treatment. When ultrasound is determined by 3 points: the mouth of both fallopian tubes and the upper part of its bottom that enters the uterus cavity. The uterus is classified as bicorne or doubled if the third point is below the assumed line between the ovaries of the fallopian tubes or no more than 5 mm above it. In such a situation, hysteroscopic correction of blemish is impossible. In those cases when the third point is more than 5 mm higher than the line connecting the ovaries of the fallopian tubes, a partial or full septum is diagnosed in the uterine cavity; elimination of such a defect in the development of the uterus is considered possible with hysteroscopy.

Intrauterine synechiae

The possibilities of ultrasound in the diagnosis of intrauterine fusion are limited. In some cases irregular contours of the endometrium are visualized, in the presence of hematomas, an anechoic formation that fills the uterine cavity is determined.

In amenorrhea, transvaginal ultrasound can be used to determine the proliferation of the endometrium against a background of estrogen stimulation. This allows you to determine which part of the uterine cavity is covered with functional endometrium, which facilitates the conduct of treatment activities and is very important in determining the prognosis. Hydro sonography allows to identify single intrauterine fusion in cases where there is no complete obstruction in the lower part of the uterine cavity.

Complications of intrauterine contraception

When the removal of IUD is performed under the control of hysteroscopy, it is necessary to conduct a preliminary ultrasound. The ultrasound pattern produced by the IUD depends on the shape and type of the contraceptive. Each type of CMV has a characteristic clear echogenic image, which can vary depending on the location of the contraceptive in the uterus. Optimal should be considered such an arrangement of BMD, when its distal part is localized in the bottom, and the proximal does not reach the level of the internal pharynx.

With a pathological displacement of the IUD, its proximal part is visualized in the upper third of the cervical canal. The most serious complication of intrauterine contraception is uterine perforation. It may be incomplete (BMC penetrates into the myometrium) or full (BMC partially or completely beyond the uterus).

If there is an IUD in the uterine cavity, pregnancy may occur. In the early period, it is not difficult to determine the IUD: it is located outside the fetal egg and, as a rule, in the lower part of the uterus.

[11], [12], [13], [14], [15], [16], [17], [18]

Postpartum complications

In the diagnosis of postpartum uterine disease before the hysteroscopy, ultrasound is given paramount importance. Ultrasound can track the postpartum involution of the uterus in the dynamics, assess the condition of the uterine cavity, the suture on the uterus after cesarean section, which is of great importance for the selection of adequate therapeutic tactics.

The accuracy of ultrasonic diagnostics of placental tissue delay is almost 100%. Diagnosis in the first days after delivery is based on the detection in the enlarged uterine cavity echogenic formation with uneven contours and spongy structure. Further, the echogenicity of the delayed lobule of the placenta increases. Placental polyp in transvaginal ultrasound is defined as the formation of an oval form with a pronounced hyperechoic structure.

The ultrasonic picture of endometritis in transvaginal ultrasound is characterized by an increase in the anteroposterior size of the uterine cavity and the accumulation of structures of various echoes in it. In a number of observations against the background of the unexpanded uterine cavity, small hyperechoic inclusions are determined and, what is especially important, attracts attention the increased echogenicity of the walls of the uterine cavity, caused by the inflammatory process.

Assessment of the condition of the suture on the uterus after cesarean section. It seems possible to visualize hematomas under the bladder-uterine fold of the peritoneum (they are often not clinically diagnosed) and an abscess in the area of the suture on the uterus. Such ultrasound indices of inflammatory changes in the area of the uterus seams, such as a decrease in echogenicity, appearance of linear structures with pronounced echogenicity, heterogeneity of the myometrium structure, merging of separate reflections from suture material into solid lines, etc.

Insolvency of the suture on the uterus is diagnosed on the basis of revealing a defect in the form of a deep niche of a triangular shape; it is possible to determine the thinning of the myometrium in the seam area.