Utility of targeted balloon protection of the venous sinus for endovascular treatment of dural arteriovenous fistula by transarterial embolization with Onyx: A case report and literature review

Background: Onyx has already been reported as an effective and safe agent in transarterial embolization of cranial dural arteriovenous fistula (d-AVF). However, successful treatment is related to not only complete shunt obliteration but also preservation of a normal route of venous drainage. Here, we present a case of transverse sigmoid d-AVF in which successful treatment was achieved by transarterial Onyx embolization with targeted balloon protection of the venous drainage. Case Description: A 70-year-old man presented with a 3-month history of tinnitus in the left ear and mild headache. Magnetic resonance imaging (MRI) showed a cluster of abnormal blood vessels in the area of the left transverse sinus (TS)-sigmoid sinus (SS) junction. Cerebral angiography demonstrated a Cognard type IIa d-AVF at the left TS-SS junction, supplied mainly by vessels such as the left middle meningeal artery, left occipital artery, and left meningohypophyseal trunk. In the venous phase, the ipsilateral TS-SS was recognized as a functional sinus and the left vein of Labbe drained into the TS near the drainage channel. Based on these findings, we decided to perform endovascular treatment under a transarterial approach with Onyx using targeted balloon protection of the venous sinus to protect against Onyx migration and preserve antegrade sinus flow. The patient recovered well without sequelae, and follow-up MRI 12 months later showed complete disappearance of the d-AVF. Conclusion: This treatment strategy using targeted balloon protection may be very useful to preserve antegrade sinus flow in patients with Cognard type IIa d-AVF.

Endovascular revascularization of symptomatic chronic total occlusions of the internal carotid artery using a proximal balloon protection device

To investigate the feasibility, efficacy, and safety of endovascular recanalization for symptomatic chronic internal carotid artery occlusions (ICAO). Thirty patients with symptomatic chronic ICAO were treated using the endovascular recanalization method. Proximal balloon protection devices were used to prevent embolic migration by completely blocking the blood flow. The morphology of the internal carotid artery (ICA) at the occluded segment based on catheter angiography was analyzed. Recanalization of symptomatic chronic internal carotid artery occlusion (CICAO) was successful in 20 of the 30 patients (66.7%). The time required for successful revascularization ranged from 120 to 180 min (mean, 150 min). Of the 20 successful patients, 14 were at the cervical ICAs, and six were at the intracranial ICAs. No permanent complications occurred in our study. Ischemic symptoms related to chronic ICAO did not occur during the 18.3 month follow-up period (range, 12–24 months) in the 20 successful patients. Endovascular revascularization can improve hemodynamic compromise. The treated sites of all 20 successfully recanalized patients were patent on computed tomographic angiography or carotid duplex sonography, and no case with >50% restenosis was observed during the follow-up period. Three patients with failed recanalization had a stroke during the follow-up period. Endovascular revascularization of symptomatic CICAO using a proximal balloon protection device is technically feasible in selected patients, and the outcomes are favorable for patients who benefit from revascularization.

Retrograde three-dimensional rotational angiography: A novel method for the detection of plaque protrusion during carotid artery stenting under continuous distal balloon protection

Background To prevent ischemic complications during carotid artery stenting, accurate detection of plaque protrusion and appropriate additional treatment are essential. Here, we introduce a novel method for the detection of plaque protrusion under distal balloon protection using three-dimensional rotation angiography—“retrograde 3DRA.” We evaluated the safety and efficacy of this method. Materials and methods We retrospectively analyzed 28 consecutive carotid artery stenting procedures under distal balloon protection at our hospital between July 2017 and August 2019. The first line of protection was dual balloon protection (proximal and distal balloon). After stent deployment, balloon dilatation, and subsequent blood aspiration, 3DRA was performed with the injection of diluted contrast medium from the aspiration catheter positioned just proximal to the distal protection balloon. The stent lumen was analyzed by obtaining the reconstruction maximum intensity projection image. Results Among the 28 cases, all cases could be assessed for in-stent plaque protrusion using “retrograde 3DRA.” We were able to evaluate the stent lumen clearly. There were three cases (10.7%) in which plaque protrusion could be confirmed. Since additional balloon dilatation was performed for all protrusion cases under continuing balloon protection, no ischemic complications occurred. Conclusion Retrograde 3DRA could be safe and useful for the detection of plaque protrusions and to avoid ischemic complication for tolerable cases of internal carotid artery transient balloon protection.

Safety and efficacy of an open-cell stent and double-balloon protection for unstable plaques: analysis of 184 consecutive carotid artery stentings

IntroductionIn our institute, most cases of carotid artery stenosis are treated by carotid artery stenting (CAS) with an open-cell stent and double-balloon protection, even if plaques are unstable. This study was performed to examine the outcome of CAS with an open-cell stent and double-balloon protection for unstable plaques.MethodsA total of 184 CAS procedures in our institute between October 2010 and February 2018 were assessed. Ultrasonography findings of low-echo plaques, plaque ulceration, or both were defined as unstable plaques. A plaque-to-muscle ratio (PMR) of >1.8 on T1-weighted black blood imaging using spin-echo was also defined as an unstable plaque. Seventy-four unstable plaques on ultrasonography and 86 unstable plaques evaluated by PMR were included. Open-cell stents and double-balloon protection (proximal balloon protection during lesion crossing and distal balloon protection after lesion crossing) were used in all cases.ResultsOn ultrasonography, perioperative asymptomatic thromboembolization was significantly more frequent in the unstable plaque group (39/74, 52.7%) than in the stable plaque group (41/110, 37.3%, p=0.0384). Asymptomatic thromboembolization was also significantly more frequent in the PMR >1.8 group (44/86, 51.2%) than in the PMR <1.8 group (36/98, 36.7%, p=0.0489). However, symptomatic thromboembolization was rare (n=5, 2.7%), and all of these patients had minor stroke. During the 4-year follow-up, the risk of ipsilateral stroke was 0.28% and 0.27% per year in patients with symptomatic and asymptomatic lesions, respectively.ConclusionsThe outcomes of CAS with an open-cell stent and double-balloon protection are acceptable. This method is effective and safe, even if carotid artery stenosis comprises unstable plaques.