Interventional Neuroradiology

The marginal tentorial artery runs over the free edge of the tentorium. Different origins have been described, always involving branches of the carotid artery. We report the superior cerebellar artery as an unknown origin of this artery. We developed our strategy in a case of a tentorial meningioma mainly supplied by this artery.

A 53-year-old man was admitted in our institution for the surgical treatment of a large tentorial and petroclival meningioma. A 2D conventional angiogram was insufficient to detect the tumoral blush. A 3D digital subtraction angiogram (DSA) of the vertebral artery highlighted a blush arising from a marginal tentorial artery fed by the superior cerebellar artery. Selective embolization of this branch led to significant devascularization of the tumor. A total tumor resection was performed 24 h after embolization without complication. The dural medial tentorial artery of the superior cerebellar artery is relatively unknown and courses at the inferior surface of the tentorium. We report the first case in which the marginal tentorial artery arises from this artery. Major bleeding may result from its section or its avulsion from the superior cerebellar artery during surgery; its preoperative diagnosis is thus essential. In this case, a 3D-DSA with dual volume visualization was more sensitive than a 2D conventional angiogram to detect such an anatomic variant.

The marginal tentorial artery may originate from the superior cerebellar artery. The recognition of this anatomic variant may be essential to avoid hemorrhagic complications during surgery of hypervascular tumors of the tentorium.

Investigation of the venous system surrounding a tumor that is invading a dural sinus is of great use for guiding the surgical excision. Non-invasive imaging is often inadequate since enhancement of the tumor causes it to blend with the contrast of the venous vascular structures. Conventional two-dimensional angiography is also often insufficient.

The objective of this study was to report regarding the potential of three-dimensional digital subtracted computed tomography angiography (3D DS-CTA) as a technique to preoperatively explore these tumors.

We retrospectively studied the radiological and surgical features of patients explored with 3D DS-CTA for a tumor invading a major dural sinus.

Three patients were included in this study, one hemangiopericytoma and two meningiomas. 3D DS-CTA allows for accurate assessment of the patency of the sinus, the location of the secondary intra- and trans-osseous venous outlets, and surgical guidance by neuronavigation.

3D DS-CTA could be a promising guiding and diagnostic tool for the pre- and intraoperative treatment of vascular tumors invading the dural sinuses, for which the venous morbidity and mortality is substantial.

A major complication of internal coil trapping for vertebral artery dissection (VAD) is medullary infarction associated with perforator occlusion. Currently, higher spatial resolution imaging can be obtained with high-resolution cone-beam computed tomography (VASO CT), and the efficacy of perforator visualization adjacent to VAD was examined.

Eight patients who underwent internal coil trapping or stent-supported coil embolization underwent VASO CT to evaluate perforators around VAD. Visualization of perforators was compared with conventional digital subtraction angiography (DSA) and three-dimensional rotational angiography (3D-RA). Postoperative MRI was performed in all patients to investigate ischemic complications. The relationship between the perforators and the infarction was analyzed.

Perforator visualization was much clearer on VASO CT than on 2D DSA or 3D-RA. It was sharp enough to identify each perforating artery. Medullary infarctions were detected in two cases. In these two cases, each ischemic lesion corresponded to the territory of a perforator that was well visualized on VASO CT. The axial view with adjoining tissue structures on VASO CT was useful to detect the territories of perforators.

VASO CT is an efficient modality for the detection and identification of perforators in the vicinity of VAD. It provides accurate anatomical information about the vertebrobasilar system that is useful for the treatment of unruptured VAD.

Intracranial wide-neck aneurysms at the arterial bifurcations, especially in the aneurysms where the bifurcating branches emanate directly from the base of the aneurysm, have been particularly difficult on which to perform endovascular treatment. The ‘Y’-configuration, double stent-assisted coil embolization is an option for the treatment of these difficult aneurysms, allowing the closure of the aneurysm, preserving the parent arteries.

In a nine-year period, 546 intracranial aneurysms in 493 patients were treated at our center by endovascular approach. We have reviewed the medical records and arteriographies from November 2007 to January 2017 of 45 patients who were treated using ‘Y’-configuration double Neuroform® stent-assisted coil embolization.

All patients were successfully treated.

The location of the aneurysms were: middle cerebral artery (MCA) 20 (44.4%), anterior communicating artery (AComA) 17 (37.7%), basilar four (8.9%), internal carotid artery (ICA) bifurcation three (6.6%) and posterior communicating artery (PComA) one (2.2%).

The mRS at hospital discharge was: mRS 0: 42 (93.3%), mRS 1: 1 (2.2%), mRS 2: 1 (2.2%) and mRS 5: 1 (2.2%).

The Modified Raymond-Roy Occlusion Classification, in the control at six months, was: Class I: 41 (91.1%), Class II: 2 (4.4%), Class IIIa: 1 (2.2%) and Class IIIb: 1 (2.2%).

Forty-four (97.8%) patients had a good outcome (mRS < 2) at six months. One (2.2%) patient had a poor outcome (mRS > 2) at six months that was due to sequelae of SAH.

There was no mortality at six months.

This technique is safe and effective for the endovascular treatment of difficult wide-neck bifurcation aneurysms, allowing the stable closure of the aneurysm, preserving the parent arteries.

Segmental arterial mediolysis (SAM) is an uncommon or underdiagnosed arteriopathy that presents with life-threatening hemorrhage. SAM can affect the intracranial, spinal, and visceral arteries, with reported cases of concomitant intracranial and visceral hemorrhage.

We present the case of a 61-year-old male with concurrent subarachnoid and intraperitoneal hemorrhage caused by simultaneously bleeding posterior spinal artery and splenic artery pseudoaneurysms. The posterior spinal artery pseudoaneurysms were treated with selective injection of polyvinyl alcohol particles into the posterior spinal artery, while the splenic artery pseudoaneurysm was treated with Gelfoam embolization. The constellation of imaging, clinical, and laboratory features led to a presumptive diagnosis of SAM, which remains the only reported cause of concurrent neurovascular and visceral artery aneurysm rupture.

SAM is a key diagnostic consideration in cases of concomitant intracranial, spinal, and visceral artery aneurysm rupture.

Blunt head trauma can injure the cavernous segment of the internal carotid artery (ICA). This may result in a carotid cavernous fistula (CCF). Rarely, a traumatic aneurysm may bleed medially causing massive epistaxis.

We present two cases of traumatic intracavernous carotid pseudoaneurysms with delayed massive epistaxis. The patients were managed with endovascular treatment involving coil embolization with parent vessel sparing and detachable balloon occlusion with carotid sacrifice. Early clinical outcome was good in both patients. Wherever possible, the CARE¹ guidelines were followed in the reporting.

These cases illustrate the delayed nature of traumatic aneurysms and the need for a high index of suspicion in the presence of skull base fractures. The use of endovascular detachable balloon occlusion and coil embolization treatment with parent vessel preservation is shown.

The anterior or posterior choroidal artery is often recruited to supply deep location arteriovenous malformations (AVMs). This study is to report curative and adjunctive AVM Onyx embolization through these arteries.

This study retrospectively reviewed six patients with cerebral AVMs who underwent endovascular embolization through the choroidal arteries between October 2015 and October 2016. Embolization was performed as a curative procedure in five patients and adjunctive procedure in one patient.

Four patients underwent embolization through the anterior choroidal artery (AchA), and two patients underwent embolization through the lateral posterior choroidal artery (LPchA). One of the four patients in whom embolization was from the AchA (distal to the plexal point) developed transient hemiparesis. Complete obliteration was confirmed by angiography at the last follow-up in five patients.

Onyx embolization of cerebral AVMs through the choroidal arteries is possible as a curative or adjunctive procedure.

The aim of the study was to assess the efficacy of balloon angioplasty-assisted mechanical thrombectomy without urgent stenting in the carotid artery as another approach for endovascular treatment of tandem occlusions.

Fifteen consecutive cases of tandem occlusions treated with the endovascular approach between January 2014 and May 2016 were reviewed. The study cohort included patients with an etiology of large vessel atherosclerosis. Extracranial carotid stenting was performed in another session if post-thrombectomy mRS modified Rankin Score (mRS) was 0–2. Good clinical outcome was determined by follow-up at 7–10, 30 and 90 days according to the mRS.

Most patients (80%) were male. Eight (53.4%) patients received intravenous thrombolysis before angiography. Proximal revascularization was successful in 100% of cases with balloon angioplasty internal carotid artery (ICA) origin. Successful recanalization (modified thrombolysis in cerebral infarction (mTICI) 2b-3) (mTICI 2 b–3) occurred in 12 cases (80%) and good clinical outcomes were achieved in 10 patients (66.7%). Cervical ICA stent placement was performed in 10 patients with good clinical outcomes. No symptomatic intracranial hemorrhage occurred after delayed ICA stenting

This is the first reported case series to evaluate this approach for endovascular treatment of tandem occlusions. Carotid angioplasty-assisted mechanical thrombectomy without urgent stenting seems to be a safer approach.

The purpose of this article is to assess the efficacy and safety of manual aspiration thrombectomy (MAT) using a Penumbra catheter in patients with anterior cerebral artery (ACA) occlusions.

From January 2012 to March 2016, 16 patients underwent MAT with Penumbra catheters using a proximal and distal supporting technique to treat ACA occlusions. We evaluated immediate angiographic results and clinical outcomes by reviewing patient electrical medical records.

Of these patients, 11 had a complete obstruction of the distal internal carotid artery (ICA) and five had ACA and middle cerebral artery (MCA) occlusions. All patients achieved successful recanalization of the distal ICA or MCA (Thrombolysis in Cerebral Infarction (TICI) grade ≥2b). Overall the recanalization rate for ACA occlusions (TICI grade≥2b) was 93.7% (15/16). The median procedure time was 45 minutes (range: 35–65 minutes). No patients were observed to have a procedure-related subarachnoid hemorrhage. Four patients (25.0%) died during hospitalization because of massive symptomatic hemorrhage, brain edema, or herniation. At discharge, the median NIHSS score for surviving patients was 6 (range: 1–17). Five patients had favorable clinical outcomes (modified Rankin scale ≤2).

MAT appears to be safe and successfully achieves recanalization in patients with ACA occlusions.

The efficacy of the endovascular treatment of acute ischemic stroke has been substantiated by several recent randomized clinical trials. While intra-arterial therapy has significantly evolved in recent years, anatomic cerebrovascular variants and disease burden can present challenges to timely recanalization. We present the first reported case of anterior-to-posterior mechanical clot retrieval with use of a stent retriever.

A 53-year-old man presented with basilar artery thrombosis. Endovascular mechanical clot retrieval was performed. The typical, antegrade, access to the basilar artery thrombus was precluded by the findings of a hypoplastic left vertebral artery and an occluded proximal right vertebral artery. Given a number of factors including the patient’s worsening symptoms and the high morbidity and mortality associated with basilar stroke, cross-circulation—anterior-to-posterior—intra-arterial therapy was performed. Thrombectomy of the basilar thrombus was achieved via the right internal carotid artery and right posterior communicating artery.

To our knowledge, we report the first case of cross-circulation, anterior-to-posterior thrombectomy, with the use of a stent-retriever device. Cross-circulation stroke treatment may be beneficial in cases of proximal vessel occlusion or anatomical constraints. Larger studies will need to evaluate the safety and efficacy of these approaches.

The objective of ischemic stroke (IS) treatment is to achieve revascularization in cerebral arteries to restore blood flow. However, there is no available method to extract arterial flow data from clinical CTA images. We developed 3D Stroke Arterial Flow Estimation (SAFE), which provides blood flow data throughout the Circle of Willis based on 3D CTA and allows comparison of arterial flow distribution in the brain.

We implemented a newly developed 3D vascular reconstruction algorithm for clinical stroke CTA images.

Based on the patient-specific vascular structure, SAFE calculates time-resolved blood flow information for the entire Circle of Willis and allows quantitative flow study of IS cases. Clinical IS cases are presented to demonstrate the feasibility. Four patients with CTA images and CT perfusion data were studied. To validate the SAFE analysis, correlation analysis comparing blood flow at the MCA, ICA, and BA was performed.

Different blood flow patterns were found in individual IS patients. Altered flow patterns and high collateral flow rates were found near occlusions in all cases. Quantitative comparison of blood flow data showed that SAFE obtained flow data and CTP were significantly correlated and provide complementary information about cerebral blood flow for individual patients.

We present SAFE analysis for collecting detailed time-resolved cerebral arterial flow data in the entire Circle of Willis for IS. Further study with more cases may be important to test the clinical utilization of SAFE and helpful to the study of the underlying hemodynamics of stroke.

Preoperative meningioma embolization may be performed with microparticles or liquid embolic agents. The pressure cooker technique (PCT) has recently been described for the embolization of brain arteriovenous malformations (AVMs).

We present the case of a 73-year-old woman with a large frontal interhemispheric meningioma that was successfully preoperatively embolized with the PCT using Squid 12, a new ethyl-vinyl alcohol copolymer embolic agent. The PCT presents considerable advantages relative to conventional embolization techniques such as deeper and faster tumor penetration and embolization of tumors with difficult vascular access, and retrograde feeling of pial afferents may be achieved.

The use of the PCT with Squid 12 may potentially increase the effectiveness of meningioma embolization, increase tumor devascularization and improve outcomes of surgical resection.