An electrolytically-detachable microcoil is introduced here in the paper. The testing results indicate that, the microcoils have stable mechanical properties, clear radiographic images and fine insulation performance. Their detaching time varies from 30s to 200s when voltage changes from 2V to 5V.
Embolization, Therapeutic ; instrumentation ; Equipment Design ; Intracranial Aneurysm ; therapy

BACKGROUNDAneurysms with wide-necked or a large neck/fundus ratio, especially located on an arterial bifurcation or a small artery, are challenges for interventional neuroradiologist because of the risk of coil migration or coil protrusion into the parent vessels. Our study was designed to improve the efficacy and safety of the "remodeling technique" with the HyperForm balloon for these difficult aneurysms and was confirmed by a follow-up result.

METHODSFrom June 2004 to September 2006, forty-two patients (20 men, 22 women) with wide-necked or large neck/fundus ratio aneurysms were treated by using the "remodeling technique" with the HyperForm balloon.

RESULTSForty wide-necked aneurysms were successfully treated with the HyperForm balloon remodeling technique with only two failed cases. Final results consisted of total occlusion in 34 cases (80.9%), subtotal in 4 (9.5%) and incomplete in 2 (4.8%). One aneurysmal rupture occurred, but no clinical consequence was shown. No thromboembolic events were observed during treatment. Final angiographic follow-up time ranged from 3 to 18 months.

CONCLUSIONSThe "remodeling technique" with the HyperForm balloon is a very useful tool in the treatment of wide-necked or unfavorable neck/fundus ratio intracranial aneurysms-located on an arterial bifurcation or a small artery and, especially, located on the bifurcation of a large artery and a small one. In our experience, this technique provided a safe and efficient treatment for difficult aneurysms when the standard remodeling technique might have failed.

Angioplasty, Balloon ; instrumentation ; methods ; Female ; Humans ; Intracranial Aneurysm ; therapy ; Male

The formation mechanisms of rare intracranial aneurysms are various, which lead to various kinds of treatment methods. The present article summarized the pathogenesis, pathologic changes in vascular walls and imaging features of rare intracranial aneurysms including segmental ectasia, aneurysms with dissection, aneurysms with intramural hemorrhage, mycotic aneurysms, aneurysms related to HIV, neoplastic aneurysms and traumatic aneurysms through literature review.
Diagnostic Imaging ; Dilatation, Pathologic ; Humans ; Intracranial Aneurysm ; diagnosis ; pathology ; therapy

BACKGROUNDStent placement has been widely used to assist coiling in cerebral aneurysm treatments. The present study aimed to investigate the hemodynamic effects of stenting on wide-necked intracranial aneurysms.

METHODSThree idealized plexiglass aneurismal models with different geometries before and after stenting were created, and their three-dimensional computational models were constructed. Flow dynamics in stented and unstented aneurismal models were studied using in vitro flow visualization and computational fluid dynamics (CFD) simulations. In addition, effects of stenting on flow dynamics in a patient-specific aneurysm model were also analyzed by CFD.

RESULTSThe results of flow visualization were consistent with those obtained with CFD simulations. Stent deployment reduced vortex inside the aneurysm and its impact on the aneurysm sac, and decreased wall shear stress on the sac. Different aneurysm geometries dictated fundamentally different hemodynamic patterns and outcomes of stenting.

CONCLUSIONSStenting across the neck of aneurysms improves local blood flow profiles. This may facilitate thrombus formation in aneurysms and decrease the chance of recanalization.

Embolization, Therapeutic ; methods ; Humans ; Hydrodynamics ; Intracranial Aneurysm ; therapy ; Stents

A new stent with triangular wire cross-section was proposed. The new stents were compared with traditional circular wire cross-section stent in the same porosity in order to investigate its effectiveness in treating intracranial aneurysms. Three models were established separately, including the aneurysm model with circle cross section stent, the aneurysm model with triangular cross section stent and the aneurysm model with non-stent. Then the same boundary conditions were set to contrast the resistance to flow, velocity, pressure, wall shear stress and total mesh displacement. The resistance to flow of triangular cross section stent was lower than circle cross section stent and the velocity, pressure, total mesh displacement of aneurysm model with triangular cross section stent were all higher than those of the model with circle cross section stent. Moreover, the peak value and valley value of wall shear stress in aneurysm model with triangular cross section stent were higher than those of the other. Triangular cross section stent might play a negative role to aneurysm rupturing. Thus, the therapeutic effect of stent with triangle cross section was not better than the stent with circle cross section. In the clinical application, doctors should consider the various factors, and choose the most suitable one.
Aneurysm ; therapy ; Computer Simulation ; Hemorheology ; physiology ; Humans ; Intracranial Aneurysm ; therapy ; Prosthesis Design ; Stents

In recent two years, new reports about concepts, technologies, materials, and especially new clinical trial results for endovascular treatment of cerebrovascular diseases, has provided tremendous promise for further progress. Mechanical thrombectomy becomes a guideline-recommended therapy for acute ischemic stroke patients with large vessel occlusion, which is considered as a landmark event. The superiority of endovascular coiling over neurosurgical clipping has been further proved for intracranial aneurysm. New devices are constantly developing for aneurysm occlusion. For brain arteriovenous malformation, application of detachable-tip microcatheters improves safety of embolization procedure, and successful transvenous embolization has been also achieved in a few cases. Long-term result of carotid stenting for symptomatic patients has been proved to be noninferior to carotid endarterectomy. Meanwhile, some new trials only obtain negative results, for example, endovascular stenting for intracranial or vertebral artery stenosis both show worse outcomes compared with medical therapy alone. More advancements and investigations are needed.
Embolization, Therapeutic ; instrumentation ; Endarterectomy, Carotid ; Humans ; Intracranial Aneurysm ; therapy ; Intracranial Arteriovenous Malformations ; therapy ; Stents ; Stroke ; therapy ; Thrombectomy ; Vertebrobasilar Insufficiency ; therapy

OBJECTIVETo explore the causes, prevention, and management of the complications during intracranial aneurysm embolization with controllable coils (mechanical detachable spiral, MDS; and Guglielmi detachable coil, GDC).

METHODSRetrospective review of 120 cases with 125 intracranial aneurysms embolized with controllable coils from March 1995 to July 1999 was conducted. The 20 accidents (in 18 cases) including aneurysm rupture, over-embolization, protrusion of coil end into the parent artery, and thrombosis of the parent artery were analyzed.

RESULTSAmong the 20 accidents, there were 6 aneurysm ruptures, 6 over-embolizations (in 5 cases), 6 coil protrusions, and 2 thromboses (one was secondary to coil protrusion). The embolization-related mortality was 3.33% (4/120), the permanent neurological deficit was 1.67% (2/120), and the transitory neurological deficit was 3.33% (4/120). The occurrence and outcome of the complications were related to the embolizing technique, the pattern of aneurysm and its parent artery, the imperfection of embolic materials, and the observation and management during embolization.

CONCLUSIONSkilled embolizing technique, better understanding of the angio-anatomy of an aneurysm and its parent artery, correct judgement and management during embolization, and improvement of embolic materials are beneficial to the reduction of complications and to the melioration of the outcome of complications.

Aneurysm, Ruptured ; etiology ; Embolization, Therapeutic ; adverse effects ; instrumentation ; Humans ; Intracranial Aneurysm ; therapy ; Retrospective Studies ; Thrombosis ; etiology

OBJECTIVETo explore the diagnosis and treatment strategy of multiple intracranial aneurysms (MIA).

METHODSWe retrospectively analyzed 96 patients with MIA (234 aneurysms). The rupture site was determined on the basis of computed tomographic and angiographic findings, and the supposed ruptured aneurysm was treated with coiling OR clipping. All the patients' records were reviewed including all computed tomographic scans and angiograms.

RESULTSTwelve patients received conservative treatment, 56 patients were treated by endovascular embolization, and 28 patients received clipping; 44 patients received one-stage treatment, and 4 patients needed a second therapy. In 36 patients, only the ruptured aneurysm was eliminated. The clinical outcomes of these 84 patients evaluated by Glasgow Outcome Scale grades were: absence of deficits in 62 patients, minor deficits in 12 patients, major deficit in 8 patients; death occurred in 2 cases. Thirty patients were available for a 6-month follow-up with DSA, which revealed stable occlusion of the aneurysms in 29 patients and the need of a retreatment due to recanalization in only one patient.

CONCLUSIONCorrect localization of the rupture aneurysm based on a comprehensive diagnosis is key to MIA treatment. All the aneurysms should be treated in one session whenever possible to protect the patient from rebleeding.

Aneurysm, Ruptured ; diagnosis ; therapy ; Embolization, Therapeutic ; Humans ; Intracranial Aneurysm ; diagnosis ; therapy ; Retrospective Studies ; Tomography, X-Ray Computed

OBJECTIVETo evaluate the therapeutic effect of embolization combined with endovascular stenting in the for treatment of intracranial pseudoaneurysms.

METHODSSeventeen patients with intracranial pseudoaneurysms received endovascular treatment with coil placement, NBCA glue embolization and endovascular stenting, and the therapeutic effect was evaluated according to the findings in immediate postoperative and follow-up angiography.

RESULTSFatal aneurysm rupture occurred in 1 case during embolization, and the surgical procedures were carried out smoothly in the remaining 16 cases. The aneurysm cavity dense coil packing ratio was 50% in coil embolization group and 42.9% in stent-assisted coil embolization group. In the follow-up for 3 months to 2 years, 2 patients in coil embolization group experienced pseudoaneurysm recurrence and were managed successfully with additional embolization with coils and stent. Aneurysms were not found postoperatively in stent-assisted coil embolization group.

CONCLUSIONEmbolization combined with endovascular stenting is a safe and effective treatment of intracranial pseudoaneurysms with minimized risk of recurrence.

Adolescent ; Adult ; Aneurysm, False ; therapy ; Embolization, Therapeutic ; Female ; Humans ; Intracranial Aneurysm ; therapy ; Male ; Middle Aged ; Stents ; Treatment Outcome ; Young Adult

Aneurysmal subarachnoid hemorrhage (aSAH) is a kind of hemorrhagic stroke with high mortality and morbidity. Although the preoperative diagnosis, surgical clipping, endovascular treatment, and intensive care have progressed in recent years, the overall prognosis of aSAH patients remains poor. In 2011, the Neurocritical Care Society organized an international, multidisciplinary consensus conference addressed the critical care management of SAH. In 2012, the American Stroke Association (AHA) updated the guidelines of diagnosis and treatment of aSAH published in 2009. In 2013, European Stroke Organization established the guideline for management of intracranial aneurysms and SAH. In 2014, the Korean Society of Interventional Neuroradiology (KSIN) published clinical practice guideline for the management of ruptured and unruptured aneurysms. The guideline for diagnosis and management of aSAH for Chinese patients has been drafted in this year. Thus, the diagnosis and management of aSAH is a hot topic in neurosurgery. This editorial summarizes the above mentioned guidelines and focuses on the progress and update of these guidelines. In this article we discuss the advantage and disadvantage of those imaging techniques, the pros and cons of surgical clipping and endovascular treatment.
Humans ; Intracranial Aneurysm ; diagnosis ; therapy ; Neurosurgical Procedures ; Practice Guidelines as Topic ; Prognosis ; Subarachnoid Hemorrhage ; diagnosis ; therapy