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101.
Zusammenfassung Die Frage der Kausalität eines offenen Foramen ovale bei ischämischem Schlaganfall sowie der optimalen Sekundärprävention dieser Patienten wird derzeit kontrovers diskutiert. Die beste verfügbare Evidenz stammt aus Fall-Kontroll-Studien, die in ihrer Gesamtheit auf einen Zusammenhang hindeuten, diesen aber letztlich nicht beweisen können. Neben paradoxen Embolien sind andere Pathomechanismen denkbar, deren genauer Nachweis in der Praxis jedoch nur selten gelingt. Bei niedrigem Rezidivrisiko zumindest für jüngere Patienten kann bei der momentanen Studienlage keine evidenzbasierte Empfehlung zur Sekundärprävention gegeben werden. Mehrere derzeit laufende randomisierte Studien sollen hier in einigen Jahren Klärung bringen. Primäres und sekundäres Risiko erscheinen jedoch deutlich erhöht bei begleitendem Vorhofseptumaneurysma. Zur weiteren Risikostratifizierung sollte der Einfluss begleitender Faktoren wie Shuntgröße und Gerinnungsstörungen weiter untersucht werden. 相似文献
102.
Stroke after varicella vaccination 总被引:3,自引:0,他引:3
Two children presented with acute hemiparesis 5 days and 3 weeks following varicella vaccination. Both showed unilateral infarction of the basal ganglia and internal capsule, a distribution consistent with varicella angiopathy. Both children had small patent foramen ovale (PFO), and one child also had severe iron-deficiency anemia, which may have predisposed the patient to this adverse effect. 相似文献
103.
Augoustides JG Weiss SJ Weiner J Mancini J Savino JS Cheung AT 《Journal of cardiothoracic and vascular anesthesia》2004,18(6):725-730
OBJECTIVE: To evaluate multiplane transesophageal echocardiography (TEE) for detection of patent foramen ovale (PFO) and to compare multiplane TEE with visual inspection (VI) for PFO detection. DESIGN: A prospective observational study. SETTING: University hospital (single institution). PARTICIPANTS: Patients presenting for cardiac surgery requiring TEE. INTERVENTIONS: Multiplane TEE including 2 atrial views with color-flow Doppler (CFD) and contrast echocardiography (CE) with a provocative respiratory maneuver (PRM) and comparison of multiplane TEE and VI with respect to PFO detection. MEASUREMENTS AND MAIN RESULTS: The cohort size was 187. PFO prevalence was 27.3%. CFD with serial decrease of the Nyquist limit detected 51% of all PFO: 41.2% in the bicaval view alone, 27.5% in the 4-chamber view alone, and 9.8% in both views. CE detected 78.4% of all PFO: 72.5% with PRM, 45.1% with no PRM, and 27.4% with/without PRM. PFO detection by multiplane TEE and visual inspection were correlated in 41 subjects. TEE diagnosed 11 PFO (26.8% prevalence, 3 missed by VI). VI diagnosed 12 PFO (29.3% prevalence, 4 missed by TEE). CONCLUSIONS: Multiplane TEE is a gold standard for detection of PFO. Despite advances in TEE technology, 2-dimensional imaging does not detect all PFO. To maximize PFO detection, multiple TEE modalities are required in multiple views, despite a low Nyquist limit for CFD or a PRM for CE. Even though multiplane TEE is equivalent to VI for PFO detection, the discrepancy rate may be an important consideration in the individual case. 相似文献
104.
Abstract.
Right-to-left shunt due to patent foramen ovale is a well-established risk factor for stroke in the young. The magnitude of shunt seems to be correlated to the risk of stroke in individuals. We report the cases of two 51-year-old identical twins, with similar risk factors for ischemic stroke, in which the sibling with a large and permanent shunt suffered a left hemispheric stroke and the other, with a small and latent shunt, was asymptomatic. In a three-year follow-up, the siblings were both asymptomatic, and the dimensions of shunts were unchanged. Our cases stress the importance of quantifying right-to-left shunt in order to stratify the risk of stroke in individuals, and suggest a role of heredity in patency of foramen ovale. 相似文献
105.
Zusammenfassung Der juvenile ischämische Insult (Alter bis 45 Jahre) stellt eine diagnostische und therapeutische Herausforderung unter den Schlaganfallsyndromen dar. Ätiologisch kommen eine Vielzahl von z. T. seltenen Krankheiten in Betracht. Vor allem müssen nichtatherosklerotische Arteriopathien — mit der Gefäßdissektion als Hauptvertreter —, paradoxe Embolien und Thrombophilien berücksichtigt werden. Bei flüchtigen Insulten ohne Nachweis struktureller Läsionen kann eine Abgrenzung zu nichtvaskulären Krankheiten (sog. Pseudoinsulten) v. a. einer Migräneaura, einem epileptischen Anfall und einer dissoziativen Störung schwierig sein. Daher führen juvenile Insulte zu einem erheblichen diagnostischen Mehraufwand, der die evidenzbasierten Mindestanforderungen weit übersteigt. Zahlreiche Therapiestrategien beruhen nicht auf großen randomisierten Studien und müssen auf individueller Basis gestaltet werden. Trotz guter Patientencompliance beträgt das jährliche Risiko für Reinsulte etwa 2–3% und für Myokardinfarkte etwa 1%. 相似文献
106.
Xin Li Yun-Hua Gao Sheng-Zheng Wu Hong-Mei Xia 《Ultrasound in medicine & biology》2018,44(11):2267-2273
A patent foramen ovale (PFO) is considered a risk factor for neurologic events. The goal of the study described here was to assess the feasibility, advantages, diagnostic sensitivity and accuracy of contrast transthoracic echocardiography examination (cTTE) using 50% glucose as a contrast agent in comparison with the use of agitated saline as contrast to screen for PFO. In our study, we found that the peak time, effective duration and duration of microbubbles produced by 50% glucose were all longer than those produced by the physiologic saline. The sensitivities for detection of PFO with cTTE using physiologic saline and 50% glucose as contrast were 83% (20/24) and 100% (24/24), respectively. TEE suggested a PFO in 24 patients in two groups. Use of 50% glucose as a contrast agent in cTTE examination enables ultrasound technicians to easily observe the right-to-left shunt across the PFO. However, the sensitivities for detection of PFO with cTTE using 50% glucose did not statistically significantly differ from those for physiologic saline. 相似文献
107.
Foramen magnum meningiomas are challenging tumors, requiring special considerations because of the vicinity of the medulla
oblongata, the lower cranial nerves, and the vertebral artery. After detailing the relevant anatomy of the foramen magnum
area, we will explain our classification system based on the compartment of development, the dural insertion, and the relation
to the vertebral artery. The compartment of development is most of the time intradural and less frequently extradural or both
intraextradural. Intradurally, foramen magnum meningiomas are classified posterior, lateral, and anterior if their insertion
is, respectively, posterior to the dentate ligament, anterior to the dentate ligament, and anterior to the dentate ligament
with extension over the midline. This classification system helps to define the best surgical approach and the lateral extent
of drilling needed and anticipate the relation with the lower cranial nerves. In our department, three basic surgical approaches
were used: the posterior midline, the postero-lateral, and the antero-lateral approaches. We will explain in detail our surgical
technique. Finally, a review of the literature is provided to allow comparison with the treatment options advocated by other
skull base surgeons. 相似文献
108.
Dusan Pavcnik MD PhD Kurt Takulve BS Barry T. Uchida BS Maja Pavcnik Arnol MD PhD William VanAlstine DVM PhD Frederick Keller MD Josef Rösch MD 《Catheterization and cardiovascular interventions》2010,75(6):861-867
Purpose: To evaluate the feasibility, effectiveness, and safety of a porcine small intestinal submucosa (SIS)‐covered Biodisk (BD) for the closure of patent foramen ovale (PFO) in swine. Methods: Twelve piglets (9–30 kg) with PFO ranging in size from 6 to 12 mm were used for the in vivo testing. The BD device consisted of two basic nitinol wire components covered with platinum coil, a flexible SIS‐covered ring, and an anchor. The BD was advanced through an 8‐Fr sheath from the femoral vein. Nine acute animals were used to test the BD for deployment, stability, immediate shunt closure, and device repositioning before or after its detachment. To assess retrievability, four devices were deployed and intentionally embolized into the RA (n = 2) and LA (n = 2). The effectiveness of the device was evaluated by angiocardiography. EKG was recorded before and after PFO closure for 3 hr. From the 12 animals, nine were acute and three were followed; one for 6 weeks, one for 12 weeks, and one for 16 weeks. Results: Successful device implantation was achieved in all animals with no shunting of contrast media observed during follow‐up in. One animal needed to have device repositioned for complete PFO occlusion because of suboptimal placement at the first attempt. The device was easily placed and retrieved before detachment in all nine animals in the acute study. None of the BDs spontaneously embolized during release or on follow‐up. EKG did not demonstrate arrhythmias during or after treatment. Four intentionally embolized BDs were easily retrieved with an Amplatz goose neck snare. Macroscopic and histologic evaluation of the three long‐term animals showed that devices were well incorporated in the atrial septum with complete shunt closure. The SIS showed progressive remodeling with the host cells. There was also progressive endothelization of the BD device. Conclusion: The BD device deployment is feasible, safe, and effective. Long‐term studies are needed to evaluate its long‐term effectiveness. © 2010 Wiley‐Liss, Inc. 相似文献
109.
The linear dimensions and volume of the posterior fossa, and the length of the supra-occiput and the clivus in children with Chiari I malformations (CMI) were studied. A statistical relationship between patient demographics, radiological features, posterior fossa and occipital bone morphometry in the study and control groups was investigated. The results of 21 pediatric patients was compared to those of a matched control group. The posterior fossa volume (PFV) of an adult CMI group was also studied. Linear measurements were used to calculate the length of the occipital bone, spherical PFV and intracranial volume (ICV) using pre-operative MRI and CT scans. A PFV to ICV ratio was obtained to standardize the comparison. The volumetric measurement in the pediatric study group was also compared to the adult CMI group.The antero-posterior dimension, width, and volume of the posterior fossa and the PFV to ICV ratio in pediatric CMI patients was significantly lower than in the control group (p < 0.05). There was no statistical difference in the length of the clivus and the supra-occiput between the two pediatric groups. The difference in the PFV to ICV ratio between pediatric and adult CMI patients was not statistically significant. Thus, the authors provide a simple, yet accurate, and reproducible method of comparison of posterior fossa volume in patients with CMI in different age groups, based on linear measurements. There is no significant difference between the length of the occipital bone at the base of the skull in pediatric CMI patients and the normal pediatric population. Development of the clivus due to late fusion of the sphenoid and occipital synchondroses in the second decade could result in manifestation of the disease in adulthood in CMI patients who were asymptomatic as children. 相似文献
110.
颅底卵圆孔、棘孔和破裂孔是X线照片观察颅骨肿瘤转移,特别是鼻咽癌转移的重要骨性标志。X线检查方法最为简便。作者对200具正常干颅骨的听眶位和听眦位颅底片作了三孔形状、位置、大小和清晰度的分析,结果表明影响其X线表现的因素很多。作者讨论了这些因素,认为听眦位显示卵圆孔最清晰,而破裂孔的解剖外口极不规则,听眶位能很好显示内口,后者作为观察标志是适宜的。此外,作者认为不能仅仅以大小的轻微改变(不大于0.5mm)作为癌肿破坏的依据。 相似文献