Pelvic arteriovenous malformation treated by superselective transcatheter venous and arterial embolization

Double Microballoon-occluded Ethanol Embolization for Pelvic Arteriovenous Malformation: A Case Report

A 40-year-old man was incidentally found to have right-sided pelvic arteriovenous malformation (AVM) with an aneurysmal dominant outflow vein (DOV). The AVM had two main feeding arteries forming a cluster of fine vessels shunt to the DOV. As transvenous approach was impossible due to anatomical difficulty, transarterial ethanol embolization was performed under simultaneous double microballoon occlusion of the two feeding arteries in combination with protective coil embolization of the prostatic branches. Ethanol (13 mL) was intermittently injected from both microballoon catheters until the AV shunt was completely occluded. At 1-year follow-up, contrast-enhanced CT revealed shrinkage of the thrombosed DOV without any symptom. Our case demonstrated the usefulness of simultaneous double microballoon-occluded ethanol embolization for treating a localized pelvic AVM with a few feeding arteries.

Stereotactic Body Radiotherapy (SBRT) for an Extracranial Arteriovenous Malformation of the Pelvis

Extracranial arteriovenous malformations (AVMs) are rare pathological, benign conditions that are characterized by aberrantly connected arteries and veins without normal intervening capillary vasculature. Although stereotactic radiosurgery is an established, efficacious, safe treatment for intracranial AVMs, there is no known published data on the use of stereotactic body radiotherapy (SBRT) for the treatment of abdominopelvic AVMs. One patient with an extracranial AVM in the pelvis that was only partially responsive to embolization was treated with SBRT to a dose of 21 Gy, delivered in three fractions over six calendar days. At presentation, the patient was non-ambulatory due to neuropathic pain from a sciatic impingement of the AVM. The patient underwent two prior catheter-based embolization procedures that had achieved partial obliteration, but with the persistence of neuropathic pain and symptoms. After SBRT to the pelvic AVM, the patient had marked improvement in pain over 10 months and was able to ambulate again. Follow-up angiography and CT demonstrated the obliteration of previously visualized AVM. We describe the first known report of pelvic AVM successfully treated with a combination of embolization and SBRT. Three-fraction SBRT to a total dose of 21 Gy appears to be safe and effective for extracranial AVMs arising in the pelvis. This strategy may be considered for patients with pelvic AVMs that are refractory to standard interventional therapies. However, these findings should be validated in larger cohorts.

Paravesical space arteriovenous malformation as a specific subgroup of pelvic vascular anomaly: a case series and review of literature

Treatment of pelvic arteriovenous malformations (AVMs) is frequently challenging because of the complex structures and anatomical diversity among cases. We present a case series of six patients with pelvic AVMs. All patients had a similar anatomical structure consisting of multiple feeders from the unilateral internal iliac artery, collecting into a dilated venous sac in the unilateral paravesical space and draining into a single outflow, eventually joining the pre-prostatic vein or internal iliac vein. Five among these patients were successfully treated by catheter-directed embolo-sclerotherapy. In addition to our six cases, we identified six previous case reports of pelvic AVM with similar anatomical characteristics. Herein, we summarize the clinical and anatomical features of these 12 paravesical AVM cases. In all cases, the patients were men; the AVM was predominantly located at the right paravesical space and demonstrated good therapeutic effect of catheter-directed embolosclerotherapy. These paravesical AVMs may constitute a new subgroup of pelvic vascular anomalies with the same etiology that are treatable by adequate catheter intervention.

Transvenous embolization for a huge pelvic arteriovenous malformation associated with prominent outflow veins

We describe the case of an adult female with a huge pelvic arteriovenous malformation (AVM) measuring approx. 8 × 10 × 13 cm, treated via the transvenous approach alone. Management of huge pelvic AVMs is challenging; there is no consensus on a standardized treatment strategy. In our patient, multiple arterioles shunted to prominently dilated outflow veins. Selective occlusion of prominent outflow veins as close to the nidus as possible achieved significant flow reduction through the nidus. Our treatment may be a safe and acceptable option to control hematuria for huge pelvic AVMs associated with prominent outflow veins, especially when both transarterial embolization and direct puncture are difficult.

Fibrodysplastic implications for transvenous embolization of a high-flow pelvic arteriovenous malformation in Osler-Weber-Rendu syndrome

Osler-Weber-Rendu syndrome is a rare genetic disorder that commonly features high-flow arteriovenous malformations (AVM) within the pulmonary, intracranial, and visceral circulation. We present a patient with a unique case of Osler-Weber-Rendu syndrome featuring a high-flow pelvic AVM in addition to fibromuscular dysplasia affecting multiple vascular beds. This required a unique modification of our embolic therapeutic approach for adequate treatment of the AVM.

Pelvic arteriovenous malformation treated by transarterial glue embolisation combining proximal balloon occlusion and devascularisation of multiple feeding arteries

We present a case of a 70-year-old man with abdominal aortic aneurysm and coincident pelvic arteriovenous malformation (AVM). Before the operation for the aneurysm, we embolised the pelvic AVM that had multiple feeding arteries and an aneurysmal-dilated draining vein. After decreasing the number of the feeding arteries by coil embolisation, an n-butyl-2-cyanoacrylate/lipiodol mixture (1:1) was injected into the prominent feeding artery and nidus with proximal balloon occlusion of the right internal iliac artery to decrease the flow to the nidus. The mixture (1:4-8) was also added for the finer feeding arteries that became apparent after the initial procedure to embolise the rest of the nidus. A follow-up study showed no contrast enhancement of the nidus and aneurysmal draining vein.