Magnetic resonance imaging findings in ovarian torsion post in vitro fertilization

Abstract

Patients who get pregnant after being treated with in vitro fertilization (IVF) are at significantly increased risk of ovarian torsion compared to the general population and also in comparison to patients who get pregnant normally [1,2]. The risk is further increased in patients who develop ovarian hyperstimulation syndrome [1]. This possibility should be considered in this group of patients presenting with acute abdominal pain and immediate management should be commenced. Here, we report 2 patients who received treatment for infertility with IVF and developed ovarian torsion and we discuss their management including the imaging workup. The first case is a 34-year-old woman at 11 + 3 weeks of gestation after IVF who presented with a 12-hour acute right lower abdominal pain with nausea and vomiting. She underwent an ultrasound examination and then further evaluated with magnetic resonance imaging which showed asymmetric enlargement of the right ovary and stromal edema and a diagnosis of ovarian torsion was made. The patient underwent laparoscopic detortion and the ovary was salvaged. The second case is a 33-year-old woman at 9 weeks of gestation after IVF who presented with intermittent abdominal pain, vaginal bleeding, and nausea and vomiting for 5 days but became worse on the fifth day. Ultrasound and subsequently magnetic resonance imaging were performed which confirmed hyperstimulation syndrome. Abnormal location of the left ovary anterior to the uterus with higher volume as well as the clinical progression raised the possibility of ovarian torsion and prompted a diagnostic laparoscopy which showed right ovarian torsion and detortion was performed.

Keywords: Complication; In vitro fertilization; Ovarian torsion; Pregnancy.

Fig. 1

Patient 1: 34-year-old female at 11 + 3 weeks of gestation after in vitro fertilization. Pelvic ultrasound images: (a and b): demonstrate asymmetric enlargement of the right ovary (volume: right ovary 43.2 cm³, left ovary 18.7 cm³). (c and d): Color Doppler interrogation demonstrate presence of arterial and venous flow within the right ovarian parenchyma with normal spectral flow in (d) gravid uterus (UT). (Color version of figure is available online.)

Fig. 2

Patient 1: Coronal T2-WI of the pelvis demonstrates swollen right ovary with stromal edema manifested by hyperintense T2 signal of the stoma and prominent follicles (blue arrow), free fluid in the right iliac fossa (white arrow). (Color version of figure is available online.)

Fig. 3

Patient 1: Axial T2-weighted images of the pelvis with fat saturation. The right ovary is enlarged and demonstrates T2 hyperintense signal of the stroma (white arrow in a), in comparison to the normal left ovary which demonstrates normal T2 signal intensity (blue arrow in b). The right ovary was proven to be torted in laparoscopic surgery. (Color version of figure is available online.)

Fig. 4

Patient 2: 33-year-old female at approximately 9 weeks and 3 days gestational age after in vitro fertilization. Pelvic ultrasound images demonstrate massive asymmetric enlargement of both ovaries with multiple bilateral prominent follicular cysts representing ovarian hyperstimulation syndrome (a). The left ovary measures 281 cm³ in volume and the right ovary measures 10 cm³ in volume (a and b). Color Doppler interrogation demonstrates presence of flow within the right ovary (d), however, intra-operatively, the right ovary was torted and the left ovary was normal despite being larger in volume. (Color version of figure is available online.)

Fig. 5

Patient 2: (a) axial T2 WI with fat saturation and (b) T2 WI without fat saturation. Both images demonstrate massively enlarged ovaries (RO and LO) with multiple follicular cysts and stromal edema representing ovarian hyperstimulation syndrome post IVF. The asymmetric enlargement of the left ovary (LO) and its location anterior to the uterus raised the possibility of left ovarian torsion. Intra-operatively, the left ovary was normal and the right ovary was torted. In ovarian hyperstimulation syndrome, the diagnosis of ovarian torsion remains challenging even with MRI.