Bicornuate uterus: uterine-fusion abnormality resulting in 2 separate uterine horns.
Fusion anomaly: uterine malformation due to disorder of fusion of embryologic tissue that normally fuses to form the uterus.
Hydrometrocolpos/hematometrocolpus: water (hydro) or blood (hemato) within uterine lumen and upper vagina.
Septated uterus: uterine malformation with smooth fundal contour associated with thick septum.
T-shaped uterus: malformed uterus that is wider than normal, and has T-shaped endometrial lumen.
Uterine artery (fibroid) embolization: interventional radiographic technique in which catheters are used to embolize flow to fibroids.
The ability of sonography, in particular transvaginal sonography (TVS), to depict subtle changes in the myometrium and endometrium makes it the diagnostic modality of choice for the evaluation of many uterine disorders. With sonography, the uterus can be imaged in several scan planes. Because the images are obtained in real time, the sonographer can empirically alter the scanning plane and gain settings for optimal depiction of the endometrium and myometrium. Because of its proximity to the uterus, a transvaginal transducer/probe can enhance the sonographic depiction of the uterus and endometrium.
Once a uterine lesion is suspected clinically, transvaginal sonography can be used to establish the presence, size, extent, and internal consistency of the lesion and to detect associated pathology, such as liver metastases. Sonography has a major role in differentiating palpable uterine masses from those that arise from adnexal structures. The specific diagnosis can be confirmed by endometrial biopsy, through dilation and curettage (D&C); by other imaging techniques, such as hysterosalpingography; and, in some cases, even by direct hysteroscopic visualization. Magnetic resonance imaging (MRI) and computed tomography (CT) can also demonstrate uterine and parauterine anatomy, and are particularly useful in staging known uterine neoplasms.
Transvaginal sonography has an important role in establishing the presence of adenomyosis, a common cause of pelvic pain. Although the TVS findings may be subtle at times, the solicitation of pain when the uterus is scanned is another useful hint to the probability of adenomyosis.
Transrectal sonography (TRS) and transabdominal sonography (TAS) may be useful in certain operative uterine procedures such as difficult D&Cs and placement of a tandem within the uterine lumen for localized radiation therapy.
Three-dimensional (3D) sonography has been shown to be useful in the evaluation of uterine anomalies. Three-dimensional ultrasound (US) affords depiction of the uterine fundus in the coronal plane, which is vital in distinguishing a bicornuate uterus from a septate uterus. Please refer to Chapter 47 for a more extensive discussion.
This chapter discusses and illustrates the sonographic features of the most common uterine malformations and disorders. Sonographic evaluation of the endometrium is discussed in detail in Chapter 34. For the sonographer and sonologist to distinguish normal from pathologic findings, a short discussion of the sonographic features of the normal uterus follows comments concerning scanning technique.