The clinical presentation and pertinent laboratory analysis often determine the appropriate imaging differential in evaluating any woman presenting with pelvic symptoms.

In a patient with a positive pregnancy test, sonography is the modality of choice to evaluate the pregnancy and any complications. In other patients who are not pregnant and present with pelvic pain or a mass, ultrasound is also the first imaging modality utilized.

Computed tomography (CT) is primarily utilized for staging of pelvic malignancies or suspected bowel abnormalities, such as appendicitis or diverticulitis. However, CT performed for other reasons, including abdominal pain, may detect and may be diagnostic in certain pelvic abnormalities.

Magnetic resonance imaging (MRI) is typically performed in situations where a pelvic mass is detected, but not fully characterized by sonography. This article emphasizes the use of ultrasound and MRI in assessing ovarian/adnexal masses. The authors will not focus on patients with a positive [beta]-hCG or other problems, such as dysfunctional uterine bleeding or uterine enlargement.

Imaging

In evaluating any pelvic mass, it is important to first determine if the mass is arising from the ovaries, the uterus, or another location. If the anatomical location of the mass can be determined, then imaging may be extremely helpful in establishing a more precise diagnosis. For instance, if the mass is of ovarian origin, determining whether it is cystic, solid, or complex is very helpful. Likewise, identifying the presence of any fat or calcium in the mass is important.

Ultrasound

Ultrasound may be extremely helpful in evaluating cystic or solid adnexal masses.

Table 1 is a noninclusive list of common cystic and solid adnexal masses that may be detected--and in many cases diagnosed--by sonography. A comprehensive discussion of all adnexal masses is beyond the scope of this pictorial review. However, a recent article by Levine D., et al published in Radiology in 2010, summarized the Society of Radiologists in Ultrasound (SRU) consensus statement on management of asymptomatic ovarian and other adnexalcysts. (1) Based on the consensus, in the premenopausal female, simple ovarian cysts that are [less than or equal to] 3 cm without color flow need not be followed. In postmenopausal females, small simple cysts [less than or equal to] 1 cm also need not be followed. This consensus statement also reviewed other common features of cysts and presented specific recommendations, which may include follow-up ultrasound at 6 to 12 weeks in certain situations. For worrisome cysts, such as those with multiple or thick septations, color flow within the septation or solid nodules, MRI or surgical evaluation is recommended. Tables 2 and 3 give a summary of the SRU recommendation. Many of these specific entities will be discussed within this article. (1)

Ultrasound is very helpful in diagnosing a number of entities. Ovarian torsion is a common entity that may be diagnosed with sonography. Usually, there is an associated ovarian mass and an enlarged ovary. The torsed ovary may be in an abnormal position, with or without decreased color flow. At times, the ovaries may "torse" then "detorse."...