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Der Hirnstamm ist als anatomische Struktur von herausragender Bedeutung, weil von hier aus sämtliche Vitalfunktionen gesteuert werden, weshalb selbst bei kleinsten Läsionen größte Auswirkungen für den Patienten entstehen. Mit der herkömmlichen Magnetresonanztomographie lassen sich funktionelle Einheiten innerhalb des Hirnstamms und der zugehörigen Bahnsysteme nicht abgrenzen. Die Abgrenzung unterschiedlicher Fasersysteme in dieser Region gelingt jedoch durch den Einsatz der Diffusionstensor-Bildgebung (DTI). Die Analyse von hochaufgelösten DTI-Datensätzen erlaubt die Berechnung einzelner Faserbahnen durch ein sog. Fiber-Tracking oder die Segmentierung von Volumenbereichen, in denen die gefundene Vorzugsrichtung ähnlich verläuft. Durch ein geeignetes Segmentierungsverfahren kann ein aufgenommener Volumendatensatz vollständig in Teilvolumina zerlegt werden. Dabei werden diejenigen Bildpunkte zu Clustern zusammengefasst, bei denen die Vorzugsrichtungen in benachbarten Bildpunkten einen gewählten Wert nicht überschreiten. Im Bereich des Hirnstamms können mit diesem Verfahren die großen Faserstränge wie die Pyramidenbahn, die unteren, oberen und mittleren Kleinhirnstiele separat dargestellt werden. Dazu ist allerdings ein mehrstufiges Vorgehen notwendig, bei dem sukzessive ansteigende Grenzwerte für den Segmentierungsprozess eingesetzt werden. Durch die Anwendung eines solchen Verfahrens konnten bei drei gesunden Versuchspersonen erfolgreich die Faserverbindungen des Hirnstamms und der Verlauf der Kleinhirnstiele dargestellt werden.

In the past years, technical developments have raised recanalization rates of endovascular treatments of intracerebral artery occlusions in acute ischemic stroke. By using stent retrievers, several prospective trials have reported recanalization rates up to 79 % as well as good neurological outcome in up to 58 % of the cases. The degree of the recanalization and the length of the procedure are factors known to influence the clinical outcome of patients treated endovascularly. Yet, still little is known about factors influencing the angiographic results of thrombectomy procedures. The purpose of this study was to investigate whether the use of intermediate catheters affects the angiographic results of thrombectomy procedures in basilar artery occlusions. A total of 47 consecutive patients with acute basilar artery occlusions who underwent endovascular treatment with stent retrievers in our department were retrospectively identified. We analyzed the angiographic data regarding the use of intermediate catheters, the lengths of the procedures, the number of passes of the stent retrievers, the angiographic results, and the site of access to the basilar artery. Recanalization with modified thrombolysis in cerebral infarction (mTICI) ≥ 2b was achieved in 74.5 %. Intermediate catheters were used in 13 cases. The mean length of the procedures was significantly shorter when intermediate catheters were used (44.8 ± 27.6 vs. 70.7 ± 41.4 min, P = .043). There were no significant differences in the number of passes or in the final mTICI scores. The use of intermediate catheters significantly reduces the length of mechanical thrombectomy procedures in acute basilar artery occlusions.

The diagnosis of 4H leukodystrophy (hypomyelination, hypogonadotropic hypogonadism, and hypodontia) is based on clinical findings and magnetic resonance imaging (MRI). Recently, mutations of the genes encoding Pol III (RNA polymerase III) subunit A (POLR3A) and subunit B (POL3B) have been identified as the genetic causes of hypomyelination. We describe two Polish female siblings aged 5 and 10 years with compound heterozygous mutations in POLR3B. They both presented with similar clinical symptoms and MRI findings presenting as 4H leukodystrophy, and the association of polymicrogyria and cataract. According to our observation in young children with the absence of hypogonadotropic hypogonadism, brain MRI pattern is very essential in proper early diagnosis of 4H leukodystrophy. All clinical and radiological results are of course helpful, however genetic conformation is always necessary.

The aim of this study is to report the authors’ initial clinical experience of a 320-detector row computed tomography (CT) scanner in cerebrovascular disorders. Volumetric CT using the full 160-mm width of the 320 detector rows enables full brain coverage in a single rotation that allows for combined time-resolved whole-brain perfusion and four-dimensional CT angiography (CTA). The protocol for the combined dynamic CTA and CT perfusion (CTP) is presented, and its potential applications in stroke, stenoocclusive disease, arteriovenous malformations and dural shunts are reviewed based on clinical examples. The combined CTA/CTP data can provide visualization of dynamic flow and perfusion as well as motion of an entire volume at very short time intervals which is of importance in a variety of pathologies with altered cerebral hemodynamics. The broad coverage enabled by 320 detector rows offers z-axis coverage allowing for whole-brain perfusion and subtracted dynamic angiography of the entire intracranial circulation.

The anterior choroidal artery (AChoA) is a rare location for intracranial aneurysms. The treatment of these aneurysms may be challenging due to the risk of occlusion of such a small and eloquent artery as the AChoA. We aimed to evaluate the risk factors for complications in AChoA aneurysm treatment. We retrospectively analyzed 47 consecutive AChoA aneurysms in 40 patients treated in our institution from 1999 and 2014 by endovascular means (87%) or surgical clipping (13%). Minor (transient or minor neurological deficits) and major complications (severe permanent neurological deficits or death) were systematically recorded. The influence of patient age, sex, aneurysm size, neck size, shape, dome-to-neck ratio and treatment technique on the occurrence of procedure-related complications was evaluated. Of the patients 11 experienced procedure-related complications (5 major, 6 minor). Aneurysms with multilobed shape were significantly associated with a higher procedure-related complication rate. There was a tendency for higher major procedure-related complication rate in small volume aneurysms. We did not find any association between the other factors analyzed and occurrence of procedure-related complications. Treatment of AChoA aneurysms has an acceptable complication risk. We did not find any significant differences between surgical and endovascular treatment in terms of procedure-related complication rates. Multilobed aneurysms were significantly associated with a higher procedure-related complication rate.

The purpose of this study was to analyze the safety and efficacy of the pREset device, a stent retriever system, for endovascular mechanical thrombectomy (MT) in acute ischemic stroke (AIS) after middle cerebral artery (MCA) occlusion. Retrospectively, 48 consecutive patients (mean age ± standard deviation, 71.0 ± 11.9 years; 24 women) treated for acute MCA occlusion using pREset solely or in combination with other MT devices were identified. Recanalization success was evaluated using the modified thrombolysis in cerebral infarction score (TICI), and complications were detected by 24-h follow-up computed tomography or magnetic resonance imaging. MCA anatomy was assessed in angiograms. Clinical outcome was evaluated with National Institutes of Health Stroke Scale (NIHSS) score at admission and discharge, and modified Rankin scale (mRS) score at discharge and follow-up. Successful recanalization (TICI 2b/3) was achieved in 39 patients (81.3 %). Rate of procedure-related complications was 8.3 %. In four patients, a subarachnoid hemorrhage occurred (8.3 %), and parenchymal hematoma was detected in four patients (8.3 %). None of those events was associated with clinical deterioration. MCA curvature significantly influenced recanalization success (P < 0.005). Successful recanalization correlated significantly with lower NIHSS scores and favorable clinical outcome (mRS score 0–2) at discharge (P < 0.05). Mortality within 90 days was significantly lower in patients with TICI 2b/3 (P < 0.005). High recanalization rates, low complication rates, and a significantly improved outcome after successful recanalization strongly suggest that MT with pREset is an adequate therapy for AIS after MCA occlusion. Vessel curvature is a significant determining factor for recanalization success.

Unfavorable vascular anatomy can impede thrombectomy in patients with acute ischemic stroke. The aim of this study was to determine the prevalence of aortic arch types, aortic arch branching patterns and supra-aortic arterial tortuosity in stroke patients with large vessel occlusion. Computed tomography (CT) and magnetic resonance (MR) images of all stroke patients in an institutional thrombectomy registry were retrospectively reviewed. Aortic arch types and branching patterns of all patients were determined. In patients with anterior circulation stroke, the prevalence of tortuosity (elongation, kinking or coiling) of the supra-aortic arteries of the affected side was additionally assessed. A total of 1705 aortic arches were evaluated. Frequency of aortic arch types I, II and III were 777 (45.6%), 585 (34.3%) and 340 (19.9%), respectively. In 1232 cases (72.3%), there was a normal branching pattern of the aortic arch. The brachiocephalic trunk and the left common carotid artery had a common origin in 258 cases (15.1%). In 209 cases (12.3%), the left common carotid artery arose from the brachiocephalic trunk. Of 1598 analyzed brachiocephalic trunks and/or common carotid arteries, 844 (52.8%) had no vessel tortuosity, 592 (37.0%) had elongation, 155 (9.7%) had kinking, and 7 (0.4%) had coiling. Of 1311 analyzed internal carotid arteries, 471 (35.9%) had no vessel tortuosity, 589 (44.9%) had elongation, 150 (11.4%) had kinking, and 101 (7.7%) had coiling. With 20%, type III aortic arches are found in a relevant proportion of stroke patients eligible for mechanical thrombectomy. Nearly half of the stroke patients present with supra-aortic arterial tortuosity, mostly arterial elongation.

Phase imaging provides additional information on multiple sclerosis (MS) lesions and may in combination with mean diffusivity (MD) and magnetization transfer ratio (MTR) help differentiating heterogeneity of MS lesion pathology. Magnetic resonance imaging (MRI) was performed in 23 MS patients including diffusion tensor imaging (DTI), magnetization transfer imaging (MTI), and SWI. Mean values (MTR, MD, and homodyne filtered phase) from 138 chronic MS lesions and normal appearing white matter (NAWM) were obtained and correlations examined. For explorative analysis, a divisive hierarchical clustering algorithm was applied. Phase characteristics were an independent characteristic of chronic T2 lesions, as MTR and MD were not correlated with phase values (R = − 0.23, R = − 0.18). Dependent on MTR, MD, and phase, cluster analysis led to five lesion groups. Of the two groups with phase values close to NAWM, one presented with highest MD and most severe MTR decrease (p  =  0.01), the other with slight MD increase and MTR decrease. Two lesion groups with highest phase values (p  =  0.01) displayed slightly increased MD and moderate decrease in MTR. Clinical data including EDSS, disease duration, and age did not differ significantly between groups. Increased phase is predominantly detectable in lesions with clear MTR decrease but only moderate MD increase. Phase images seem to represent an independent parameter for MS lesion characterization and may provide additional information on MS lesion heterogeneity.