Radiology Case of the Month:Diagnosis and Treatment of an Acquired Uterine Arteriovenous Malformation in a 26-Year-Old Woman presenting with Vaginal Bleeding.

Arteriovenous malformations (AVMs) are a rare source of potentially life-threatening uterine bleeding, and should be suspected in patients presenting with metromenorrhagia. Histologically, AVMs are characterized as having both arterial and venous tissues without an intervening capillary network.1 The etiology may be either congenital or acquired secondary to prior uterine surgery or uterine malignancy.2 Congenital lesions are thought to result from arrested vascular development and contain a nidus of multiple feeding arteries anastomosed to multiple draining veins. In contrast, acquired lesions contain small fistulas between a single feeding artery and draining vein.4 While angiography is considered the gold standard for diagnosing AVMs, its limitations include exposure to contrast and radiation and the inability to accurately detect the degree of pelvic extension.5 As a result, ultrasound (US) with color Doppler is the imaging modality of choice in suspected AVM and can be confirmed noninvasively with magnetic resonance imaging (MRI).6 Angiography remains the preferred method of imaging when there is a high index of suspicion of AVM in a patient who may potentially undergo embolization as treatment.3 Historically, the definitive treatment for AVMs has been either hysterectomy or uterine artery ligation. However, embolotherapy has become a well-recognized alternative to surgery since the first reported case in 1982.5 One of the advantages of embolotherapy is the preservation of reproductive structures. Currently, treatment for AVMs is based on the patient's desire to maintain fertility. The objective of this study was (1) to describe the diagnostic features of an AVM on Doppler ultrasound in a patient who presented with vaginal bleeding and (2) discuss the treatment and outcome of this patient using uterine artery embolization.