Background: The etiology of ischemic strokes remains cryptogenic in about one third of patients, even after extensive workup in specialized centers. Atherosclerotic plaques in the aorta can cause thromboembolic events but are often overlooked. They can elude standard identification by transesophageal echocardiography (TEE), which is invasive or at best uncomfortable for many patients. CT angiography (CTA) can be used as an alternative or in addition to TEE if this technique fails to visualize every part of the aorta and in particular the aortic arch. Methods: We prospectively studied 64 patients (47 men, age 60 8 13 years) classified as having cryptogenic stroke after standard and full workup [including brain MRI and 24-hour electrocardiogram (ECG)] with ECG-triggered CTA of the aorta in search of plaques and compared the results with those of TEE. Investigators were blinded to the results of both techniques.
Background: Stroke etiology in ischemic stroke guides preventive measures and etiological stroke subgroups may show considerable differences between both sexes. In a population-based stroke registry we analyzed etiological subgroups of ischemic stroke and calculated sex-specific incidence and mortality rates. Methods: The Ludwigshafen Stroke Study is a prospective ongoing population-based stroke registry. Multiple overlapping methods of case ascertainment were used to identify all patients with incident stroke or transient ischemic attack. Modified TOAST ( Trial of Org 10172 in Acute Stroke Treatment) criteria were applied for subgroup analysis in ischemic stroke. Results: Out of 626 patients with first-ever ischemic stroke in 2006 and 2007, women (n = 327) were older (73.5 8 12.6 years) than men (n = 299; 69.7 8 11.5 years; p < 0.001). The age-adjusted incidence rate of ischemic stroke was significantly higher in men (1.37; 95% CI 1.20–1.56) than in women (1.12; 95% CI 0.97–1.29; p = 0.04). Cardioembolism (n = 219; 35.0%), smallartery occlusion (n = 164; 26.2%), large-artery atherosclerosis (n = 98; 15.7%) and ‘probable atherothrombotic stroke’ (n = 84; 13.4%) were common subgroups of ischemic stroke. Stroke due to large-artery atherosclerosis (p = 0.025), current smoking (p = 0.008), history of smoking (p < 0.001), coronary artery disease (p = 0.0015) and peripheral artery disease (p = 0.024) was significantly more common in men than in women. Overall, 1-year survival was not different between both sexes; however, a significant age-sex interaction with higher mortality in elderly women (>85 years) was detected. Conclusions: Cardioembolism is the main source for ischemic stroke in our population. Etiology of ischemic stroke differs between sexes, with large-artery atherosclerotic stroke and associated diseases (coronary artery disease and peripheral artery disease) being more common in men.
Background and Purpose: Large artery atherosclerosis (LAA) and small vessel disease (SVD) share common risk factors for stroke. We aimed at investigating the association of SVD with cerebral LAA as well as with atherosclerosis in patients with stroke likely to originate from aortic plaques. Methods: We investigated 71 consecutive patients (48 men, mean age 64.2 +/- 13 years) with ischemic stroke of undetermined cause according to the ASCO classification, who received ECG-triggered CT angiography for best available atherosclerotic plaque detection in the aorta. Results: Aortic atherosclerotic plaques were detected in 54 patients (76.1%). The presence of SVD significantly correlated with the presence of aortic plaques (p < 0.001), as well as LAA (p < 0.001) and risk factors such as arterial hypertension (p = 0.032) and diabetes mellitus (p = 0.017). Conclusions: Aortic plaques are common in patients with stroke of undetermined cause. If so, SVD and LAA are often coexisting, which demonstrates the close link of macro- and microangiopathy, at least in cases of severe risk factors of atherosclerosis. Copyright © 2012 S. Karger AG, Basel
Background: Brain imaging in stroke aims at the detection of the relevant ischemic tissue pathology. Cranial computed tomography (CT) is frequently used in patients with transient ischemic attack (TIA) but no data is available on how it directly compares to magnetic resonance imaging (MRI). Methods: We compared detection of acute ischemic lesions on CT and MRI in 215 consecutive TIA patients who underwent brain imaging with either CT (n = 161) or MRI (n = 54). An MRI was performed within 24 h in all patients who had CT initially. Results: An initial assessment with CT revealed no acute pathology in 154 (95.7%) and possible acute infarction in 7 (4.3%) patients. The acute infarct on CT was confirmed by diffusion-weighted imaging (DWI) in only 2 cases (28.6%). DWI detected an acute infarct in 50 of the 154 patients with normal baseline CT (32.5%). Among 54 patients without baseline CT, DWI showed acute ischemic lesions in 19 (35.2%). The ischemic lesions had a median volume of 0.87 cm 3 (range: 0.08–15.61), and the lesion pattern provided clues to the underlying etiology in 13.7%. Conclusion: Acute MRI is advantageous over CT to confirm the probable ischemic nature and to identify the etiology in TIA patients.
The great French organist and composer Louis Vierne (1870-1937) died while performing an organ recital at Notre Dame cathedral in Paris - right in front of the console. This historical article provides insights into the biography of a highly talented musician who was challenged by disability and diseases throughout his career. A special focus is placed on the circumstances of Vierne’s remarkable death. Until now, both a primary cerebrovascular event and a "heart attack" are discussed in reference books and encyclopedias as the immanent causes of death. From the perspective of a stroke neurologist, a reappraisal of Vierne’s medical history and the events that happened during his last concert is presented. Copyright (C) 2012 S. Karger AG, Basel
Background: The human hippocampus can be affected in a large variety of very different neurological diseases, of which acute ischemic stroke, transient global amnesia, epilepsy, and limbic encephalitis are the most common. Less frequent etiologies include various infections and encephalopathy of different origins. Clinical presentation notably comprises confusional state, altered vigilance, memory deficits of various extent and seizures. While in hypoxic or hypoglycemic encephalopathy, clinical presentation and surrounding circumstances provide some clues to reach the correct diagnosis, in the above-listed more common disorders, signs and symptoms might overlap, making the differential diagnosis difficult. This review presents recent studies using the diffusion-weighted imaging (DWI) technique in diseases involving the hippocampus. Methods: References for the review were identified through searches of PubMed from 1965 to January 2011. Only papers published in English were reviewed. Full articles were obtained and references were checked for additional material where appropriate. Results: All pathologies affecting the hippocampus are associated with distinct lesion patterns on magnetic resonance imaging, and especially DWI has the ability to demonstrate even minute and transient hippocampal lesions. In acute ischemic stroke in the posterior cerebral artery territory, involvement of the hippocampal formation occurs in four distinct patterns on DWI that can be easily differentiated and correspond to the known vascular anatomy of the hippocampus. In the subacute phase after transient global amnesia (TGA), dot-like hyperintense lesions are regularly found in the lateral aspect of the hippocampus on DWI. The DWI lesions described after prolonged seizures or status epilepticus include unilateral or bilateral hippocampal, thalamic, and cortical lesions of various extent, not restricted to vascular territories. In limbic encephalitis, DWI lesions are only infrequently found and usually affect the hippocampus, uncus and amygdala. Furthermore, in some rare cases DWI lesions of different etiology may coexist. Conclusion: In patients with diseases affecting the hippocampus, DWI appears to be useful in differentiating between underlying pathologies and may facilitate a definite diagnosis conducive to an optimal treatment. With a careful clinical examination, experience with the interpretation of DWI findings and knowledge of associated phenomena, it is indeed possible to differentiate between ischemic, ictal, metabolic, and TGA-associated findings. Copyright (C) 2011 S. Karger AG, Basel
Background: Recovery from stroke is presumed to be a function of a cerebral network. Chronic small vessel disease (SVD) has been shown to disrupt this network’s integrity and has been proposed as a predictor of poor outcome after stroke. We studied this hypothesis in patients with acute ischemic stroke of the striatocapsular region, an area of pronounced cortical and subcortical connectivity. Methods: We identified 62 patients with isolated striatocapsular stroke from our stroke registry. The standardized workup included clinical rating according to the modified Rankin Scale (mRS) and MRI, rated according to the Fazekas scale for the extent of SVD, ranging from grade 0 to III. MRS at admission, at discharge, and a short-term recovery parameter (the difference between mRS at admission and discharge) were correlated with the extent of SVD. Comorbidity was assessed with the Charlson comorbidity index (CCI). Results: SVD was graded 0 in 7%, I in 60%, II in 18%, and III in 16% of patients. The median mRS at discharge for the groups was 2, 1, 2 and 4, and the median recovery parameter was 2, 1, 1 and 0.5, respectively. The extent of SVD significantly correlated with both the mRS at discharge and the recovery parameter. While age was also a significant predictor of these outcome parameters, SVD severity was a significant predictor even after correction for age or CCI. Conclusions: SVD is a predictor of poor outcome and recovery in striatocapsular stroke, independent of age or comorbidity. Severe SVD disturbs the integrity of the cerebral network leading to aggravation of and poor recovery from neurological deficits. Copyright (c) 2011 S. Karger AG, Basel
The newly discovered brain-specific transmembrane protein CKAMP44 was shown to influence AMPA receptor function in the mouse hippocampus where the protein is differentially expressed. The low mRNA expression in CA1-neurons versus the high expression in DGneurons gives reason to hypothesize that the different CKAMP44 levels influence memory processes assigned to these subfields. The DG has long been proposed to provide the cellular substrate for the process of spatial pattern separation, whereas CA1 is assumed to be the basis of temporal pattern separation. To investigate these hypotheses, two mouse models of altered CKAMP44 expression were analyzed. Theoretically, a global knockout of CKAMP44 should influence a region with high endogenous CKAMP44 expression (DG) more than a region with low expression (CA1). Vice versa, CKAMP44 overexpression should exert a stronger influence on a region with low (CA1) than on a region with high expression (DG). Thus, the CKAMP44-/- mice served as a model to study the involvement of CKAMP44 in the DG-based spatial pattern separation. CKAMP44-/- mice failed to show any impairment in hippocampus-dependent spatial reference- and spatial working-memory tests including spatial pattern separation. In the second model, virusmediated CKAMP44 overexpression was confined to the hippocampus. Compared to Controls, CKAMP44HCoex mice made a similar number of errors during both spatial reference- and spatial working-memory test on the eight-arm radial arm maze. But a newly designed analysis of the working memory errors on the eight-arm radial arm maze and the chance-level performance during rewarded alternation revealed an impairment in the ability to process or retrieve stimulusspecific, recency-dependent memory in CKAMP44HCoex mice. Thus, the CKAMP44HCoex model adds further proof to the implicated role for CA1 in temporal pattern separation, and also provides the hitherto only model of altered hippocampal memory funciton upon manipulation of an AMPA receptor auxiliary protein.