Mirena in Two-Dimensional Ultrasound

Recently, a case report describing a woman who had two Mirena intrauterine devices (IUDs) in uterine cavity is published (1). The patient was suffering from heavy menstrual bleeding. Clinical and ultrasound examinations, laboratory tests, cervical cytology and endometrial biopsy were normal and a Mirena IUD was inserted. Six months later, she still had the same complaints. Ultrasound scan was performed and no Mirena IUD was seen in uterine cavity. A new Mirena IUD was inserted. She did not recover and admitted to another clinic where three-dimensional (3-D) ultrasound scan revealed the presence of two Mirena IUDs. The levonorgestrel intrauterine system (LNG-IUS), often referred to by its brand name Mirena, has been approved by the Food and Drug Administration (FDA) and has been used till early nineties in many countries. Mirena has a 32 mm T-shaped polyethylene frame that releases 20 μg of progestin (levonorgestrel) daily for up to 5 years. In contrast to a copper IUD, the visualization of a Mirena IUD by ultrasound is not straightforward. The two-dimensional (2-D) transvaginal ultrasonography (TVS) is the primary method for the evaluation of the location of Mirena. The absence of copper, leads to the lower image quality visualization, therefore, the imaging of Mirena needs more operator’s skills. When 2-D TVS fails, or when patients carrying Mirena have symptoms, as is seen in the case report, other diagnostic modalities are recommended. These are three-dimensional ultrasound, x-ray of the pelvis, computed tomography or magnetic resonance imaging.