Adnexal: refers to tube and ovary.
Complex mass: contains both cystic and solid components.
Cystic mass: refers to a mass containing fluid and having a thin, regular wall.
Solid mass: has solid central consistency.
Torsion: twisting of adnexa, usually resulting in compromised blood flow.
Sonography is the diagnostic modality of choice for the initial evaluation of most patients with a pelvic mass. This is particularly true for pelvic masses thought, on a clinical basis, to be benign. Although the sonographic features of a pelvic mass frequently do not permit a specific histopathologic diagnosis, sonography usually provides clinically important parameters for the pelvic mass.1 These include the following:
Confirmation of the presence or absence of a pelvic mass
Delineation of the size, internal consistency, and contour of the mass
Establishment of the origin and anatomic relationship of the mass to other pelvic structures
A survey to establish the presence or absence of abnormalities associated with malignant disease, such as as-cites or metastatic lesions
Guidance for aspiration or biopsy of selected pelvic masses
Each of these parameters will be discussed, as well as specific types of pelvic masses. This chapter is structured to emphasize the way sonographic evaluation of pelvic masses proceeds from evaluation of clinically pertinent parameters to consideration of specific lesions.
Information gained by sonography is useful in guiding the gynecologic surgeon through decisions regarding surgical intervention. In general, masses that are over 5 cm in average dimension, contain irregular solid components, or are associated with significant amounts (over 20 mL) of intraperitoneal fluid require surgical treatment.2 Similarly, pelvic masses that are associated with acute pelvic pain may require immediate surgical intervention because they may be associated with adnexal torsion.3 In contrast, masses that are completely cystic and smaller than 4 to 5 cm may be observed over a few months with repeat sonograms to document any change in size. Although small (<5 cm) adnexal masses can be detected in postmenopausal women, only a low percentage (approximately 3%) will represent a malignant neoplasm.4,5 In patients with recurrent ovarian carcinoma, sonography has been found to be highly accurate in the detection of as-cites, but it is a poor predictor of the presence of diffuse small peritoneal implants.6
The role of magnetic resonance imaging (MRI) and computed tomography (CT) relative to sonography must be considered. In general, CT and MRI are more accurate than sonography in staging histologically proven neo-plastic tumors, such as cervical carcinoma.7 Because of their high operational costs and limited availability, however, these modalities are not as frequently used in the initial evaluation of a pelvic mass as is sonography. Computed tomography and MRI are usually used as a secondary adjunctive examination when the characteristics of the mass raise concern about malignancy.
The use of transvaginal sonography can add specificity in certain areas to the conventional transabdominal sonographic examination. The limited field of view of most transvaginal transducer/probes confines their ...