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[en] Endovascular treatment for a wide-neck anterior communicating artery (AcomA) aneurysm remains technically challenging. Stent-assisted embolization has been proposed as an alternative of treatment of complex aneurysms. The X-configuration double-stent-assisted technique was used to achieve successful coiling of wide-neck AcomA aneurysm. Implanted stent can alter intra-arterial flow. Follow-up angiograms 4 months later showed flow changes due to used X-technique of stents implantation and filling of the anterior cerebral artery from the opposite internal carotid artery.
[en] Carotid stump syndrome is one of the recognised causes of recurrent ipsilateral cerebrovascular events after occlusion of the internal carotid artery. It is believed that microemboli arising from the stump of the occluded internal carotid artery or the ipsilateral external carotid artery can pass into the middle cerebral artery circulation as a result of patent external carotid–internal carotid anastomotic channels. Different pathophysiologic causes of this syndrome and endovascular options for treatment are discussed.
[en] The optimal management of patients with symptomatic severe ostial vertebral artery stenosis (OVAS) is currently unclear. We analyzed the long-term outcome of consecutive patients with OVAS who received either medical treatment (MT) or vertebral artery stenting (VAS). Thirty-nine (>70%) patients with severe OVAS were followed for a mean period of 2.8 years. The decision for VAS (n=10) or MT (n=29) was left to the clinician. The Kaplan-Meier method was used to assess the risk of recurrent stroke, transient ischemic attack (TIA), or death over the study period. Patients in the VAS group were significantly younger and more likely to have bilateral VA disease (P=0.04 and P=0.02). VAS was successfully performed in all ten patients. The periprocedural risk within 30 days was 10% (one TIA). The overall restenosis rate was 10%. One restenosis occurred after 9 months in a patient treated with bare-metal stent. At 4 years of follow-up, VAS showed a nonsignificant trend toward a lower risk for the combined endpoint of TIA and stroke in posterior circulation compared to medical treatment (10% vs. 45%, P=0.095; relative risk (RR)=0.24, 95% confidence interval (CI) 0.031-1.85). Patients with bilateral VA disease had a significantly lower recurrence risk after VAS compared with medical treatment (0% vs. 91% at 4 years, P=0.004; RR 0.10, 95% CI 0.022-0.49) VAS was performed without permanent complications in this small series of patients with symptomatic severe OVAS. The long-term benefit seems to be confined to patients with bilateral but not to those with unilateral VA disease. (orig.)
[en] Advances in imaging techniques allow for in vivo identification of abnormalities and normal variants of cerebral arteries. These arterial variations can be asymptomatic and uncomplicated although, some of them increase the risk of aneurysm formation, acute intracranial hemorrhage, play a vital role in neurosurgical planning or can be misidentified as serious pathology and medical errors. The goal of this publication is to discuss arterial anomalies of anterior cerebral circulation, their prevalence and demonstrate radiological images of some of those variants. In this article we will discuss variants of internal carotid artery, anterior cerebral artery, anterior communicating artery, middle cerebral artery, persistent stapedial artery and fenestration
[en] Objective: The Leo self-expandable stent is a new retractable stent that is delivered via a conventional catheter. The aim of this study was to evaluate the use of this stent for endovascular treatment of complex aneurysms. Methods: Twenty-eight complex cerebral aneurysms (27 saccular and 1 fusiform) in 28 patients were treated electively. They were located at the internal carotid artery (17), basilar trunk (3), anterior cerebral artery (1), anterior communicating artery (3), vertebral artery (2) and middle cerebral artery (2). One aneurysm exhibited recanalization after primary endovascular treatment without stent. Clinical outcome was assessed with the modified Glasgow Outcome Scale. Results: Deployment of Leo stent was successful in 26 lesions, and difficulties in stent positioning due to tortuous cerebral circulation in 2 cases, which were treated with Neuroform stent. Additional coil embolization was performed in 26 lesions. No permanent neurological deficits were encountered consequent to endovascular procedure. Complete or partial occlusion immediately after stent deployment was achieved in all aneurysms. There was no immediate coil embolization was chosen in 3 cases because of subsequent reduced filling of the aneurysms with contrast agent on angiograms. There were 3 asymptomatic parent artery occlusion related to the deployment of the Leo stent, one stent migration. Follow-up revealed patent stents in the remaining cases. No angiographic recurrences arose. Conclusion: The Leo stent is very useful for endovascular treatment of complex cerebral aneurysms because it is easy to navigate and place precisely. A drawback is that in-stent thrombosis caused by stent placement and stiffer delivery catheters to place larger stents.
[en] Purpose: The determination of the arterial input function (AIF) is necessary for absolute quantification of the regional cerebral blood volume and blood flow using dynamic susceptibility contrast MRI. The suitability of different vessels (ICA-internal carotid artery, MCA-middle cerebral artery) for AIF determination was compared in this study. Methods: A standard 1.5 T MR system and a simultaneous dual FLASH sequence (TR/TE1/TE2/α=32/15/25/10 ) were used to follow a bolus of contrast agent. Slice I was chosen to cut the ICA perpendicularly. Slice II included the MCA. Seventeen data sets from ten subjects were evaluated. Results: The number of AIF-relevant pixels, the area under the AIF and the maximum concentration were all lower when the AIF was determined from the MCA compared to the ICA. Additionally, the mean transit time (MTT) and the time to maximum concentration (TTM) were longer in the MCA, complicating the computerized identification of AIF-relevant pixels. Data from one subject, who was examined five times, demonstrated that the intraindividual variance of the measured parameters was markedly lower than the interpersonal variance. Conclusions: It appears to be advantageous to measure the AIF in the ICA rather than the MCA. (orig.)
[de]Ziel: Die Bestimmung der arteriellen Inputfunktion (AIF) ist notwendig fuer die absolute Quantifizierung haemodynamischer Parameter mit der dynamischen suszeptibilitaetsgewichteten Magnetresonanztomographie (DSC-MRT). Es wurde untersucht, ob sich die Arteria cerebri media (ACM) ebenso zur Bestimmung der AIF eignet wie die dem Standardverfahren zugrundeliegende Arteria carotis interna (ACI). Methoden: Es wurden ein Standard-1,5 T-MR-Tomograph und eine simultaneous dual FLASH Sequenz (TR/TE1/TE2/α=32 ms/15 ms/25 ms/10 ) verwendet, welche die simultane Akquisition von zwei Schichten ermoeglicht. Die Positionierung der zwei Bildgebungsschichten wurde so gewaehlt, dass die ACI senkrecht geschnitten wurde und Teile der ACM in der zweiten Schicht enthalten waren. Insgesamt wurden 17 DSC-MRT Untersuchungen an 10 Personen vorgenommen. Ergebnisse: Sowohl die Anzahl der AIF-relevanten Pixel wie auch das Integral unter der AIF und die ermittelte Maximalkonzentration der AIF aus der ACM waren kleiner im Vergleich zu den Werten der ACI. Die mittlere Transitzeit sowie die Zeit zum Konzentrationsmaximum waren in der ACM groesser, was die computergestuetzte Identifikation der fuer die AIF relevanten Pixel kompliziert. Die Analyse von 5 Datensaetzen einer einzelnen Person zeigte das gleiche Ergebnis und ergab darueber hinaus deutlich kleinere Schwankungen im Vergleich zu den interpersonellen Schwankungen. Schlussfolgerung: Die Bestimmung der AIF aus der ACI ist verglichen mit der prinzipiell moeglichen Bestimmung der AIF aus der ACM vorteilhafter. Die Bestimmung der AIF aus der ACM benoetigt noch zusaetzliche Korrekturen. (orig.)
[en] We describe our experience in which a retrievable Enterprise stent was used as a temporary recanalization and embolectomy device in an acute middle cerebral artery (MCA) occlusion after urgent stenting for ipsilateral carotid artery stenosis. (orig.)
[en] A case of combined vascular abnormalities is presented- an aneurysm of the internal carotid artery and arterio-venous malformation temporooccipitally on the right, clinically presented by an ischemic brain stroke in the territory supplied by the right middle cerebral artery. Treatment included - hypo-tensive drugs, antiplatelet (antiaggregants) agents and vasodilators, which lead to significant improvement of the general and focal neurological symptoms. Neurosurgical intervention is been discussed, in order to remove the vascular malformation and to prevent future vascular events. Key words: Aneurysm. Arteriovenous Malformation. Ischemic Stroke