Transabdominal two‐ and three‐dimensional color Doppler imaging of a uterine arteriovenous malformation

Abstract

Uterine arteriovenous malformation (AVM) is a rare condition that has been reported in patients ranging in age between 18 and 72 years1. Several terms have been used for uterine AVM, including arteriovenous fistula, arteriovenous aneurysm, cirsoid aneurysm, racemose aneurysm, pulsatile angioma and cavernous angioma2. Arteriovenous malformations can be congenital or acquired and consist of a ‘proliferation of arterial and venous channels with fistula formation and an admixture of small capillary-like channels’2. Congenital AVM is very rare and is the result of a defect in the embryonic development of vascular structures3,4. Most uterine AVMs are acquired following damage to the uterine tissue. Cases of acquired AVM have been attributed to a variety of causes, including pelvic trauma, surgical interventions such as dilatation and curettage and Cesarean section, cervical and endometrial carcinoma, trophoblastic diseases, inflammation and diethylstilbestrol exposure, and can be idiopathic5–8. Uterine AVMs grow slowly and the appearance of symptoms may be delayed. However, the onset of symptoms can be sudden4. Patients may suffer from irregular vaginal bleeding, heavy menses and/or abdominal pain. Bleeding is thought to occur as a result of vessels of the AVM being exposed by shedding of the endometrium. There are several signs that can indicate the diagnosis of uterine AVM; an audible bruit or palpable thrill may be present and in some cases a pulsatile mass can be detected on manual examination7. A 40-year-old woman (gravida 6, para 3, abortus 3) presented at our hospital with heavy menstrual bleeding. The bleeding was reduced by intravenous administration of 10 IU oxytocin in physiological solution and methylergonovine maleate was then prescribed until bleeding ceased. An ultrasound scan was performed 3 days after this. The patient declined to undergo a transvaginal scan. On transabdominal gray-scale ultrasound, we observed multiple irregular hypoechoic spaces in the anterior wall and fundus of the uterus, which formed a mass that extended to the endometrium Figure 1 Gray-scale transabdominal ultrasound image showing hypoechoic spaces in the anterior wall and fundal part of the uterus extending to the endometrium.