Presentation
21/40 pregnant. Acute right lower quadrant pain.
Patient Data
Mass with heterogeneous echogenicity located adjacent and connected to the gravid uterus by a bridge of hypoechoic tissue. It measures 6 cm in greatest diameter. On other images (not shown) there was mild left renal pelvicalyceal system dilatation, and the appendix was not clearly identified. The right ovary had a normal appearance.
The appendix is not clearly identified, with no inflammatory change centered on the cecal pole. There is an ovoid mass abutting the right anterior wall of the gravid uterus, with predominantly low signal, similar to the myometrium, with some internal heterogeneity and a trace of free fluid around it. It is inseparable from the uterine wall. The right ovary is seen separately as a normal structure. An incidental but common finding in pregnancy is the presence of paired tubular structures in the right retroperitoneum - the distended right ureter due to physiologic hydronephrosis, and the distended right ovarian vein.
Case Discussion
Carneous (or red) degeneration of a fibroid is a cause of acute pain in pregnancy that is usually managed conservatively. The role of imaging, principally ultrasound and MRI, is to confirm the diagnosis and seek potential alternative diagnoses such as acute appendicitis.