Diagnostic imaging of adnexal masses in pregnancy

Abstract

Adnexal masses detected during pregnancy require a prompt and accurate diagnosis to ensure fetal safety and good oncological outcomes. Computed tomography is the most common and useful diagnostic imaging modality for diagnosing adnexal masses; however, it is contraindicated in pregnant women because of the teratogenic effect of radiation on the fetus. Therefore, ultrasonography (US) is commonly used as the main alternative for the differential diagnosis of adnexal masses during pregnancy. Additionally, magnetic resonance imaging (MRI) can assist in the diagnosis when US findings are inconclusive. As each disease has characteristic US and MRI findings, understanding these features is important for the initial diagnosis and subsequent treatment. Thus, we thoroughly reviewed the literature and summarized the key findings of US and MRI to apply these in real-world clinical practice for various adnexal masses detected during pregnancy.

Keywords: Adnexal disease; Diagnostic imaging; Magnetic resonance imaging; Pregnant woman; Ultrasonography.

Fig. 1

Characteristic features of endometriomas on US. Thick and hypovascular walls (white arrow). Homogenous low internal echogenicity (asterisk). Focal calcification (red arrow). US, ultrasonography.

Fig. 2

Characteristic features of mature cystic teratoma (A) “dermoid plug” of mature cystic teratoma on US (white arrow) (B) High signal intensity of sebaceous and fat components on T1WI of MRI (asterisk). US, ultrasonography; T1WI, T1-weighted; MRI, magnetic resonance imaging.

Fig 3

Characteristic features of cystadenomas on US. (A) Serous cystadenoma: large anechoic, smooth walled unilocular cyst with multiple thin septations (white arrow). (B–D) Mucinous cystadenoma: large hypoechoic cyst (asterisk). Small hypoechoic mural nodules (red arrow). Multiple thick septations (yellow arrow).

Fig. 4

Characteristics of uterine fibroids on US. (A) Hypoechoic solid mass with edge refraction (white arrow). (B) Posterior acoustic shadowing (asterisk). US, ultrasonography.

Fig. 5

Characteristic features of borderline mucinous ovarian neoplasm on US (A–C) unilocular cyst (asterisk), honeycomb appearance (white arrow), multiple mural wall nodules (yellow arrow). (D) A septate cyst with plaque-like excrescences on T1WI of MRI (red arrows). US, ultrasonography; T1WI, T1-weighted; MRI, magnetic resonance imaging.