rrhagic cysts and their evolution (grayscale and color Doppler)

Ultrasound On ultrasound, hemorrhagic ovarian cysts demonstrate a number of different appearances as the cyst evolves. Imaging Considerations Typically, the initial appearance of a hemorrhagic cyst will demonstrate a smooth wall with anechoic interior echoes and posterior acoustic enhancement. Application of color Doppler will demonstrate circumference flow but no flow within the cyst itself. Images

Above. Hemorrhagic ovarian cyst with the anechoic interior, smooth wall, and posterior wall enhancement. Image 1

Above. Same case as immediately above. Note color Doppler demonstrates peripheral flow and no flow within the cyst itself. Image 2

Above. Another exam of hemorrhagic ovarian cyst with the anechoic interior, smooth wall, and posterior wall enhancement. Again, note color Doppler demonstrates peripheral flow and no flow within the cyst itself. Image 3.

During the evolution of a hemorrhagic cyst, the appearance may change with the demonstration of fibrin strands which appear as “fishnet, lacy reticular, or a cobweb pattern. Again, there would be no detectable flow with color Doppler. The cysts generally resolve within about 8 weeks.

Above. Lacy, reticular, “fishnet” appearance may be seen during the evolution of a hemorrhagic ovarian cyst. Image 4.

Above 2 images. The evolution of a subacute ovarian hemorrhagic cyst may demonstrate the appearance of a solid neoplasm. The color Doppler continues to demonstrate circumferential blood flow. Images 5 and 6.

Sonographic characteristics of endometriomas (grayscale and color Doppler)

Endometriomas represent endometriosis (the presence of endometrial glands and stroma) within the ovary. Imaging Considerations These lesions are also known as “chocolate cysts” of the ovary and on ultrasound have a typical ground glass appearance. Rarely, they may be multi-locular in appearance. Images

Above. Typical appearance of endometrioma with “ground glass” appearance and posterior acoustic shadowing. Image 7.

Above 2 images. Transvaginal ultrasound. Endometrioma with color Dopper demonstrating peripheral blood flow. Images 8 and 9.

Sonographic characteristics of mature teratomas (grayscale and color Doppler)

Mature teratomas are defined as having three cell lines present (ectoderm, endoderm, and mesoderm). Calcification can represent bone while hair and sebaceous material may be present. Focal or diffuse echogenic components may be present. Echogenic lines or dots may represent areas of acoustic shadowing, while calcifications may represent teeth or bones.  Nondependent fluid may be hyperechoic in appearance. Imaging Considerations The characteristics of mature teratomas (dermoid cysts) are listed in the following table.  [249]

Images

Above. Mature teratoma. Ovarian cyst with calcifications suggesting bone. Note the echogenic lines and dots which might represent acoustic shadowing. Image 10.

Above. The echogenic component in the cyst wall suggests calcification. Image 11.

Above. Abdominal X-Ray defines calcified structure in the pelvis suggestive of mature teratoma. Image 12.

Above. A mass with mixed echogenicity within the cyst wall is suggestive of hair. Image 13.

Above. Mature teratoma with a Rokitansky protuberance looking like vegetation. Image 14.

Sonographic characteristics of pedunculated leiomyomas and ovarian fibromas

Ovarian fibromas may appear similar to pedunculated subserosal uterine fibroids. The ultrasound appearance of fibromas is variable and some tumors may have cystic components. The ultrasound characteristics of fibromas have been described in detail and the following chart represents a summary of findings. [250] Ovarian Fibromas

Pedunculated Myoma In pedunculated myomas, a subserosal myoma may be identified. In addition, there may be other smaller myomas identified. A key feature would be the presence of a vascular channel (bridging vessel sign) from the main uterine body to the pedunculated myoma which would be demonstrated with the color Doppler. The presence of fluid in the pouch of Douglas is less likely with a pedunculated myoma. The continuity of an abdominal mass by a stalk on cross-sectional imaging in the absence of abdominal ascites is indicative of a pedunculated myoma. CT or MRI may confirm the diagnosis.

Images

Above. Typical ovarian fibroma. Note solid tumor with stripe-like attenuated echos. Fluid in the pouch of Douglas may be present. Image 15

Above. Uterus with pedunculated myoma closely adherent to the uterine body. Typical features (not shown) are connecting stalk and a vascular connection (bridging vessel sign). Image 16.

Sonographic characteristics of hydrosalpinges

Hydrosalpinx is defined as the filling of the Fallopian tube with clear or serous fluid. There are multiple causes but the primary cause is pelvic inflammatory disease. Other etiologies include adhesions from surgery, endometriosis, tubal ectopic pregnancy, and potentially cancer of the ovary or other organs.

Above. Schematic representative of hydrosalpinx demonstrating a fluid-filled Fallopian tube. Image courtesy, By BruceBlaus – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=46604060

Ultrasound findings in hydrosalpinx demonstrate the Fallopian tube wall to be extremely thin or in chronic conditions, the tubal wall may be thickened in which case hyperemia can be demonstrated by color Doppler. The tubal spaces are dilated and filled with fluid.

Images

Above. Cross-section of Fallopian tube with hydrosalpinx. Note the thin Fallopian tube wall and the anechoic fluid without evidence of echogenic material. Image 17.

Above. Transvaginal ultrasound. Longitudinal of the Fallopian tube. Again note the thin wall, anechoic fluid. The hyperechoic ovary with follicles is impinging upon the Fallopian tube. Image 18.

Above. Transvaginal ultrasound. Dilated fluid-filled Fallopian tube with a thin imperceptible wall. Image 19.

Above. Hydrosalpinx. Dilated fluid-filled Fallopian tube with thickened septa.  Image 20.

Above. The schematic appearance of the  “cogwheel” seen in patients with hydrosalpinx. This finding is observed in the transverse view of the fallopian tube and is caused by thickening of the mucosal longitudinal fold. Image 21.

Above. Transvaginal gray-scale ultrasound images show a cross-section of the fallopian tube with a pathognomonic cogwheel appearance s. Note the dilated fluid-filled fallopian tube with a thin wall. Image 22.

Sonographic characteristics of tubo-ovarian in the inflammatory process (tubo-ovarian Complex/abscess

A tubo-ovarian abscess is most often a consequence of pelvic inflammatory disease. The sonographic findings are not always specific but taken with the clinical picture of elevated white blood cell count and sedimentation rate as well as the physical findings of pain and fever, ultrasound can be supportive of the diagnosis. Color Doppler is useful in demonstrating abundant blood flow in the region of the mass. The following table demonstrates the sonographic characteristics of tubo-ovarian abscesses. Please note that all features are present in specific cases.

Images

Above. Transvaginal ultrasound. Tubo-ovarian abscess with mass demonstration cystic and some solid elements and septa. Image 23.

Above. Transvaginal gray-scale. Tubo-ovarian abscess. Complex multilocular adnexal mass with associated marked hyperemia (arrows). A small amount of free fluid (FF) also is present. Note the echogenic fat (*) in the surrounding soft tissues, indicating inflammation. Image 24.

Above. Transvaginal ultrasound. Color Doppler of the same patient immediately above. The normal ovarian parenchyma was not identified; this phenomenon is compatible with the destruction of the fallopian tube and ovaries with necrosis and/or liquefaction of the ovarian parenchyma. Multiple cystic components represent areas of ovarian necrosis. The fallopian tube cannot be separated from the involved ovary. Image 25

Sonographic Characteristics of Peritoneal Inclusion Cysts

Peritoneal inclusion cysts represent loculated fluid collections near peritoneal surfaces. The cysts occur in women from 18 to 89 years, and the clinical history includes traumatic injury to the structures. The cysts accumulate due to the presence of adhesions and result from a non-neoplastic reactive process. The following chart demonstrates some previous antecedent events:

Imaging Considerations The following chart represents elements for the diagnosis of peritoneal inclusion cysts as well as their imaging characteristics.

Images

Above. Transabdominal ultrasound of peritoneal inclusion cyst. Note the smooth thin wall of the cyst and the lack of nodularity. The ovary is normal demonstrating only small follicles lying near the psooas muscle. Image 26.

Above. Another transabdominal ultrasound of peritoneal inclusion cyst. Again, note the smooth thin wall of the cyst and the lack of nodularity. The ovary is normal demonstrating only small follicles. Image 27.

Above. Transabdominal ultrasound of peritoneal inclusion cyst. Note the smooth thin wall of the cyst and the lack of nodularity. The anechoic bladder is separate from the peritoneal inclusion cyst. The ovary is normal demonstrating only small follicles. Image 28.

Above.  Peritoneal inclusion cyst. Note the ovary (Ov) is suspended amongst adhesions at the periphery of the cyst. Image obtained with permission. Image 29.

Sonographic characteristics of polycystic ovaries

Polycystic Ovary Syndrome Polycystic ovary syndrome is the most common endocrine disorder in women. The syndrome is frequently characterized by secondary amenorrhea, hirsutism, and obesity. There is hypothalamic-pituitary dysfunction which affects the metabolism of both androgens and estrogens. The ovaries are thickened and sclerotic and there are multiple peripherally located follicles. The clinical, laboratory, imaging characteristics, and differential diagnosis are summarized in the following tables.

Images

Above. Transvaginal ultrasound images demonstrate enlargement of the ovaries with multiple, small, peripherally located hypoechoic follicles and slightly increased echogenicity of the central stroma. Image 30.

Above. Transvaginal ultrasound image.  Note enlargement of the ovary with multiple, small, peripherally located hypoechoic follicles and slightly increased echogenicity of the central stroma. Image 31

Ovarian hyperstimulation. Ovarian Hyperstimulation Syndrome occurs when there is overstimulation of the ovary during infertility treatment to induce ovulation. It may also be observed with increased human chorionic gonadotropin stimulation of the ovary in the presence of gestational trophoblastic disease.

Above. Transvaginal ultrasound in the sagittal plane in mild ovarian hyperstimulation syndrome. Note the cysts within the ovary and the fluid in the retro-uterine space. Image 32.

Above/ Transvaginal ultrasound. Moderate ovarian hyperstimulation syndrome. Both ovaries are in the posterior cul-de-sac. The ovaries contain several large unruptured follicles.  Image 33.

Sonographic characteristics of adnexal torsion

Ovarian torsion is defined as a complete or partial twisting or rotation of the ovarian pedicle that compromises both the arterial and venous flow to the ovary.  In most cases both the ovary and fallopian tube are involved.  Acute pelvic pain is often a presenting symptom and accurate patient evaluation is necessary to arrive at an early diagnosis so that surgical intervention can prevent loss of the blood supply to the ovary and consequent loss of ovarian function. The primary imaging modalities are ultrasound and color Doppler. Both transvaginal ultrasound and transabdominal ultrasound should be used in the suspected diagnosis and the sensitivity of ultrasound for the diagnosis of ovarian torsion is over 80%.  The area of the affected adnexa is usually tender during the application of the ultrasound probe. Imaging Considerations The following table lists the common ultrasound imaging findings for ovarian torsion:

Color Doppler should be used in the assessment of ovarian torsion and should be applied to the affected ovary and compared to the contralateral ovary.  Doppler findings are variable in ovarian torsion and minimal venous flow is common. Due to the dual blood supply of the ovaries, the normal arterial flow may be observed in the presence of torsion. The following table demonstrates the role of color Doppler flow in the presence of a twisted pedicle.

Images

Above. Right ovary in a patient with ovarian torsion. Note the ovarian enlargement. There are peripheral follicles to define this structure as ovarian. Then central ovarian stroma shows a mixed pattern of hyperechoic and hypoechoic structure. The hypoechoic areas may represent edema or blood. Image 34.

Above. This is the same patient as immediately above and demonstrates the normal contralateral ovary which is normal in size and exhibits normal architecture with the presence of ovarian follicles. Image 35.

Above. Same patient as the immediately preceding two images. Color Doppler of the enlarged right ovary with ovarian torsion shows peripheral blood flow only and no central flow. The normal left ovary demonstrates normal central blood flow to the ovary. Image 36.

Sonographic characteristics of malignant adnexal masses

Distinguishing between a benign and malignant extrauterine mass with grayscale ultrasound requires a process of learning which is termed pattern recognition and is superior to all other ultrasound methods while adding color Doppler increases confidence in diagnostic accuracy. Pattern recognition is reported to be superior to serum CA-125 for the discrimination between benign and malignant adnexal masses. Imaging Considerations The following tables illustrate the features of benign and malignant extrauterine pelvic masses. Benign Tumors Cysts without solid components are likely benign unless there are multiple cysts within the tumor in which case the diagnosis may be a borderline mucinous cystadenoma.

Malignant Tumors Malignant tumors tend to demonstrate irregularity, echogenicity, and large and irregular solid components. A strong sign of malignancy is the presence of papillary projections of greater than 3 mm. into the cyst cavity from the cyst wall and are common in borderline ovarian tumors, adenofirbromas as well as serous cystadenomas and mucinous cystadenomas.

The International Ovarian Tumor Analysis (IOTA) simple ultrasound-based rules are listed in the below table for the prediction of malignancy in adnexal mass, and are divided into five benign (B)-features and five malignant (M)-features.          The International Ovarian Tumor Analysis (IOTA)

Above. Note color Doppler blood flow as a potential distinguishing feature between a unilocular tumor and an irregular solid tumor. The color score based IOTA is as follows: 1, no detectable vascularization; color score 2, minimal vascularization; color score 3, moderate vascularization; color score 4, abundant vascularization). Using color Doppler has been considered an adjunct to imaging and to the prediction of malignancy in adnexal masses. Images

Above. Benign unilocular cyst. Note the smooth wall. There are no solid components and no papillary projections. Image 37.

Above. Benign multilocular cyst. Note the absence of solid elements and the absence of papillary projections. Image obtained with permission.Image 38.

Above. A malignant tumor is characterized by the presence of solid components and presence of irregularities. Image 39.

Above. Papillary projections occur in a primary invasive ovarian cancer.  Image 40.

Above. Benign mucinous cystadenoma. Multloculated cyst. No solid elements and no papillary projections. Image 41

Above. Borderline mucinous cystadenoma with border wall echogenicity and solid elements. Image 42

Above. Transvaginal ultrasound. Fallopian tube mixed endometrial and serous carcinoma. The fallopian tube is dilated and fluid-filled (Note anechoic fluid adjacent to the mass.) Color Doppler demonstrates the mass to be vascular and homogeneous. Image 43.