CT and MR Imaging of Gynecologic Emergencies

Abstract

Gynecologic emergencies include various diseases that result from adnexal and uterine disorders. Adnexal disorders may be classified into the following three categories: (a) disorders that cause hemorrhage (hemorrhagic ovarian cysts and ectopic pregnancies); (b) disorders related to adnexal tumors (adnexal torsion and rupture of ovarian tumors); and (c) disorders related to pelvic inflammatory disease, such as tubo-ovarian abscesses. Unusual adnexal torsion, such as massive ovarian edema, isolated fallopian tube torsion, and paraovarian cyst torsion, has also been described. Uterine disorders in gynecologic emergencies may be classified into two categories: (a) acute fibroid complications, including red degeneration of a uterine leiomyoma, torsion of subserosal myomas, and torsion of the uterus; and (b) causes of acute uterine bleeding, including retained products of conception and uterine arteriovenous malformations. Some gynecologic diseases are self-limited, while others cause infertility or life-threatening infection or bleeding if left untreated. Therefore, prompt and accurate diagnosis is important for appropriate life-saving treatment and for the preservation of fertility. The imaging findings are important when evaluating acute gynecologic diseases because the symptoms and physical examination findings are often nonspecific and limited. Ultrasonography is the first-line imaging modality; however, when a definitive diagnosis cannot be established, computed tomography (CT) and magnetic resonance (MR) imaging may narrow the differential diagnosis. Appropriate management requires radiologists to be familiar with the CT and MR imaging features of gynecologic emergencies. With respect to rare conditions, radiologists should take into account the representative findings presented in this article to increase diagnostic accuracy. RSNA, 2017.

MRI of Acute Gynecologic Conditions

“…Rupture of an ovarian cyst, either hemorrhagic or simple, may occur spontaneously, but can also be the result of trauma or pregnancy. Right‐sided ovarian cysts more frequently rupture, as it is believed the sigmoid colon acts as a protective barrier to the left ovary in the setting of direct trauma . Although ovarian cyst rupture may cause massive hemoperitoneum, most patients can be managed with conservative treatment unless they are in an unstable condition …”

“…About 20–40% of women over the age of 30 have leiomyomata . Acute onset of pelvic pain secondary to leiomyoma can be due to one of the following causes: leiomyoma degeneration, torsion of a subserosal leiomyoma, or prolapse of a submucosal leiomyoma …”

“…Red degeneration can occur with pregnancy or oral contraceptive use, and is thought to be secondary to either a leiomyoma outgrowing its blood supply, or thrombosis of the venous outflow . Leiomyoma with red degeneration may have a confounding appearance on both ultrasound and CT, appearing as a complex cystic mass . MRI can establish an accurate diagnosis in this setting.…”

“…On MRI, a hemorrhagic degenerating leiomyoma will demonstrate high signal intensity on T 1 ‐weighted images, either peripherally or uniformly, with diminished internal enhancement (Fig. ) . Signal intensity on T 2 ‐weighted images in the center of the lesion is variable, but a T 2 ‐hypointense rim is seen in most cases, reflecting a network of thrombosed dilated blood‐filled vessels at the periphery of the lesion (Fig.…”

MR Imaging of Parasitic Leiomyoma with Red Degeneration

“…The signal intensity characteristics of the rim are thought to be due to the effect of abundant intracellular methemoglobin in the obstructed vessels. 2 Parasitic leiomyoma with red degeneration is very rare. However, parasitic leiomyoma with red degeneration should be suspected if the characteristic imaging findings are detected in a woman with acute abdomen and a history of uterine leiomyoma.…”