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M Sitzer

Publications and source records attributed to M Sitzer.

At least 19 recordsLinked to original sources
PubMed2007

[Neurosyphilis: important differential diagnosis of herpes simplex encephalitis].

Diagnosis of herpes simplex encephalitis in the acute stage is based on clinical symptoms (nonspecific prodromi, neuropsychological deficits, epileptic seizures) in combination with typical CSF abnormalities (lymphomonozytic pleocytosis) and MR imaging abnormalities assumed to be typical for herpes simplex encephalitis (increased fluid-attenuated inversion recovery and T2 hyperintensities in the mesiotemporal lobe region). Definite diagnosis of herpes simplex encephalitis is based on positive polymerase chain reaction in the CSF, usually available some days after hospital admission. Suspected herpes simplex encephalitis requires immediate treatment with acyclovir. Bacterial encephalitis caused by spirochetes may present with similar features but requires different treatment. This should therefore be considered in the differential diagnosis of herpes simplex encephalitis. We report a young patient with neurosyphilis whose correct diagnosis could be made only several days after beginning specific treatment.

Adult↗
PubMed2006

Mannheim carotid intima-media thickness consensus (2004-2006). An update on behalf of the Advisory Board of the 3rd and 4th Watching the Risk Symposium, 13th and 15th European Stroke Conferences, Mannheim, Germany, 2004, and Brussels, Belgium, 2006.

Intima-media thickness (IMT) is increasingly used as a surrogate end point of vascular outcomes in clinical trials aimed at determining the success of interventions that lower risk factors for atherosclerosis and associated diseases (stroke, myocardial infarction and peripheral artery diseases). The necessity to promote further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT and to standardize IMT measurements is expressed through this updated consensus. Plaque is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. Standard use of IMT measurements is based on physics, technical and disease-related principles as well as agreements on how to perform, interpret and document study results. Harmonization of carotid image acquisition and analysis is needed for the comparison of the IMT results obtained from epidemiological and interventional studies around the world. The consensus concludes that there is no need to 'treat IMT values' nor to monitor IMT values in individual patients apart from exceptions named, which emphasize that inside randomized clinical trials should be performed. Although IMT has been suggested to represent an important risk marker, according to the current evidence it does not fulfill the characteristics of an accepted risk factor. Standardized methods recommended in this consensus statement will foster homogenous data collection and analysis. This will help to improve the power of randomized clinical trials incorporating IMT measurements and to facilitate the merging of large databases for meta-analyses.

Adult↗
PubMed2006

Increased endothelial cell apoptosis in symptomatic high-grade carotid artery stenosis: preliminary data.

OBJECTIVE: Endothelial cell (EC) apoptosis has been associated with thrombus formation on an eroded atherosclerotic plaque surface. Alongside plaque rupture, it may constitute another mechanism of plaque destabilisation. We investigated whether EC apoptosis also may be involved in plaque destabilisation in high-grade internal carotid artery (ICA) stenosis. METHODS: We compared the degree of EC apoptosis in carotid endarterectomy specimens from n=38 patients undergoing surgery for high-grade ICA stenosis (> or =70%; n=19 clinically asymptomatic; n=19 symptomatic). The total number of endothelial cells (ECs) and apoptotic cells were determined using CD31 immunohistochemistry and the TdT dUTP nick end-labeling (TUNEL) method respectively. RESULTS: Overall, EC apoptosis was a rare finding. The median percentage of apoptotic ECs was 0.0% (0.0-0.7%) in asymptomatic and 0.5% (0.0-7.3%) in symptomatic plaques (p=0.015, Mann-Whitney U test). No difference was observed between ruptured and unruptured plaque (0.0% [0.0-6.0%] vs 0.0% [0.0-5.7%]; p=0.446). CONCLUSIONS: Our results indicate that TUNEL-detected EC apoptosis is rare in carotid plaque from patients with >70% stenosis.

Aged↗
PubMed2006

[Endovascular treatment for intracranial stenoses. A common statement by neurologists and neuroradiologists].

Intracranial stenoses cause 5-10% of all strokes and are increasingly detected by means of modern imaging methods. The stroke danger of high-grade symptomatic stenoses is relatively high, with an annual risk of approximately 10% under medical treatment. Coumadin increases the risk of hemorrhage, and after risk/benefit considerations, antiplatelets should be preferred for antithrombotic therapy. Despite optimized medical treatment, a small group of patients with recurrent symptoms or symptomatic stenoses without adequate collateral supply probably carry higher spontaneous stroke risk and may be considered for intracranial stenting, which itself is associated with procedural risks of up to 10%. Currently published case series show relatively high complication rates as a major drawback of endovascular treatment, mainly strokes after occlusion of perforating branches extending from the stenotic vessel segment or hemorrhagic complications. According to data from smaller feasibility studies, stroke rates in follow-up after successful stenting seem to be low. The average rate of high-grade restenosis with possible indication for reintervention is 10%. Improvements in endovascular treatment aim at reducing vessel wall trauma during balloon angioplasty by underdilatation or the use of self-expanding stents. Until complication rates are dependably reduced to values of 5-6%, indication for endovascular treatment should be restricted to patients without therapeutic alternatives. According to limited data with large variation between different studies, a prospective multicentric registry is proposed for systematic evaluation and further development of the method.

Algorithms↗
PubMed2006

[Evaluation of different protocols for the leg cuff technique for measurement of dynamic cerebral autoregulation].

AIM: Aaslid's leg cuff method is a well validated technique to measure dynamic cerebral autoregulation. In the literature different protocols to choose cuff pressure have been described. The aim of this study is to find a technique as accurate as possible without un-necessary inconvenience for the patient. METHOD: The leg cuff test with bilateral cuffs was performed on 10 young healthy volunteers with three different protocols (cuff pressure at systolic level, doppler controlled and 30 mmHg above systolic level). For each examination the autoregulation index invented by Tiecks and Mahony was calculated. Statistical modelling of correlated data was done with Generalized Estimating Equations. RESULTS: The choice of the protocol influences the quality of the actual autoregulation test. The most reliable protocol is also the most inconvenient one for the patient. We found no systematic bias of the protocol on the autoregulation index, but the relation between induced blood pressure drop and resulting autoregulation index was close to statistical significance. CONCLUSION: For the leg cuff test with bilateral cuffs in awake patients we recommend to apply the protocol proposed by Tiecks. Additional report of the magnitude of induced blood pressure drop would be helpful to improve the results' comparability.

Blood Pressure↗
PubMed2006

[Long term follow-up after intracranial vertebro-basilar artery stenting].

PURPOSE: Recurrent ischemic symptoms attributable to intracranial high-grade vertebrobasilar artery stenoses are associated with a high risk of ischemic stroke, particularly if these occur in spite of aggressive medical treatment. Long term efficacy data for endovascular stent angioplasty of symptomatic intracranial stenoses are lacking. The purpose of this prospective study is to determine the rates of deaths, of ischemic events and of restenosis during long-term follow-up. MATERIALS AND METHODS: Between June 2001 and February 2004 twelve patients (11 male, 1 female; median 63 yrs; range, 46 - 75 yrs) with recurrent ischemic symptoms attributed to > or = 70 % intracranial vertebro-basilar artery stenoses, who had failed aggressive medical treatment, were included. Median follow-up was 24 months (range: 6 to 36 months). Intracranial stenoses were measured using 3D rotation angiography data sets and treated with balloon expandable stents. All patients were scheduled for follow-up including clinical (Barthel Index) and transcranial Doppler examinations and intraarterial angiography at 6 months after intervention. Clinical outcome was defined as the rate of stroke in any vascular territory or death during follow-up. Vascular outcome was determined by the rate of in-stent restenosis 50 % on follow-up as examined by intraarterial angiography at 6 months or by transcranial color-coded duplex sonography. RESULTS: Stent placement was technically successful in all patients. No patient had further cerebral ischemic symptoms; two patients died (1 myocardial infarct, 1 sudden death) during follow-up of median 24 months. The degree of stenoses was reduced from median 81 % (range 69 - 94 %) to 19 % (range 10 - 36 %) immediately after stent placement and to 32 % (range 22 - 48 %) after 6 months. No restenosis > or = 50 % occurred during follow-up. CONCLUSION: Based on this limited series, we believe that in patients, with recurrent symptoms despite aggressive medical treatment, endovascular stent placement in intracranial high-grade vertebrobasilar artery stenoses can be an effective and safe treatment option.

Aged↗
PubMed2006

[Post-stroke-depression. Algorithm for a standardized diagnostic approach in clinical routine].

Depression is a frequent and important complication after stroke. The occurrence of a post-stroke-depression (PSD) has a significant impact on the functional and cognitive deficit, on mortality and on quality of life after stroke. In contrast to the clinical importance, PSD is often ignored in routine management of stroke patients and remains often untreated if diagnosed. The diagnostic uncertainty is aggravated by the lack of appropriate diagnostic criteria for PSD in the International Classification of Diseases (ICD-10) used in Germany. For the first time, we present an algorithm, which allows for a standardized examination of stroke patients on the presence of PSD. All stroke patients should be examined initially by a short and simple screening tool and are subjected to more extensive procedures only if PSD is assumed based on the screening result. Furthermore potentials and limitations to convert the diagnosis of PSD into a diagnostic related group (DRG) that is used to calculate the hospital's reimbursement are highlighted. Finally pharmacological treatment options for PSD are discussed.

Algorithms↗
PubMed2005

Serum glial fibrillary acidic protein as a biomarker for intracerebral haemorrhage in patients with acute stroke.

BACKGROUND: Biomarkers of stroke are an evolving field of clinical research. A serum marker which can differentiate between haemorrhagic and ischaemic stroke in the very early phase would help to optimise acute stroke management. OBJECTIVE: To examine whether serum glial fibrillary acidic protein (GFAP) identifies intracerebral haemorrhage (ICH) in acute stroke patients. METHODS: A pilot study assessing 135 stroke patients admitted within six hours after symptom onset. Diagnosis of ICH (n = 42) or ischaemic stroke (n = 93) was based on brain imaging. GFAP was determined from venous blood samples obtained immediately after admission, using a research immunoassay. RESULTS: GFAP was detectable in the serum of 39 patients (34 of 42 (81%) with ICH, and five of 93 (5%) with ischaemic stroke). Serum GFAP was substantially raised in patients with ICH (median 11 ng/l, range 0 to 3096 ng/l) compared with patients with ischaemic stroke (median 0 ng/l, range 0 to 14 ng/l, p<0.001). Using receiver operating characteristic curve analysis, a cut off point of 2.9 ng/l provided a sensitivity of 0.79 and a specificity of 0.98 for the identification of ICH in acute stroke (positive predictive value 0.94, negative predictive value 0.91; p<0.001). CONCLUSIONS: Serum GFAP can reliably detect ICH in the acute phase of stroke. Further evaluation of the usefulness of GFAP as an early diagnostic marker of ICH is now required, with the aim of optimising cause specific emergency management.

Aged↗
PubMed2005

Phosphatidylserine IgG and beta-2-glycoprotein I IgA antibodies may be a risk factor for ischaemic stroke.

OBJECTIVE: Antiphospholipid antibodies (APLA) are established risk factors for venous thrombosis but their role in the pathogenesis of cerebral ischaemia is unclear. The purpose of the present study was to evaluate the relevance of various APLA in patients with cryptogenic stroke (group A, n = 21) and determined causes of stroke (group B, n = 104) according to the TOAST classification in comparison with healthy volunteers without any thrombotic or ischaemic event in their history (group C, n = 84). METHODS: Median ages were 52 yr (A), 60 yr (B) and 51 yr (C). Blood samples were tested for lupus anticoagulant (LA) using phospholipid-dependent coagulation tests (activated partial thromboplastin time, diluted Russell viper venom time). Confirmatory tests were performed if necessary. Furthermore, we assessed the presence of specific APLA and their antibody subclasses against cardiolipin (AclA), phosphatidylserine (ApsA), phosphatidylinositol (ApiA) and beta-2-glycoprotein I (Abeta2A) using enzyme-linked immunosorbent assay. RESULTS: For ApsA IgG we found a significantly higher prevalence in stroke patients (57.7%) compared with normal subjects (4.8%; P < 0.001). Similarly, Abeta2A IgA was significantly more prevalent in stroke patients (20.8%) in comparison with normals (3.6%; P < 0.001). For all other APLAs tested, no significant differences emerged after adjustment for multiple comparisons. We did not find significant differences between stroke subtypes for any APLA. CONCLUSION: The results of this study suggest a relevant role for antiphosphatidylserine IgG and anti-beta2-glycoprotein I IgA in stroke aetiology.

Adult↗
PubMed2005

Phosphodiesterase 4D gene, ischemic stroke, and asymptomatic carotid atherosclerosis.

BACKGROUND AND PURPOSE: Phosphodiesterase 4D (PDE4D) was identified recently as the first novel stroke gene to predispose to ischemic stroke independently of conventional risk factors. An association was only found with large vessel and cardioembolic stroke, suggesting a mechanism of accelerated atherosclerosis. We sought to replicate this association in ischemic stroke as a whole, and individual stroke subtypes, in a non-Icelandic European population. To assess a role in early atherosclerosis, we also sought associations with underlying asymptomatic atherosclerosis itself, assessed by carotid ultrasound in a community population. METHODS: A total of 737 consecutive white patients with stroke and 933 white community controls free of symptomatic cerebrovascular disease were examined using a case control methodology. For association with atherosclerosis, intima-media thickness (IMT) in a community population (n=1000) was assessed using carotid ultrasound. Nineteen single nucleotide polymorphisms (SNPs) and 1 minisatellite in the PDE4D gene were determined, with haplotyping undertaken using Phase 2.0. RESULTS: No association with ischemic stroke overall was identified. Six of the 19 SNPs were associated with cardioembolic stroke and 2 different SNPs with large vessel disease. There was no association with carotid artery IMT or carotid plaque in the asymptomatic community subjects. CONCLUSIONS: The PDE4D gene is not a major risk factor for ischemic stroke, or early atherosclerosis, within the 2 European population samples studied. On analysis of individual stroke subtypes, there is a possible association with cardioembolic stroke, but the lack of association with carotid IMT and plaque would suggest that this is via a mechanism other than accelerated atherosclerosis.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2005

[HERNS. A rare, hereditary, multisystemic disease with cerebral microangiopathy].

Hereditary endotheliopathy with retinopathy, nephropathy, and stroke (HERNS) is an autosomally dominant inherited, multisystemic disease presenting with leukoencephalopathy, progressive visual loss, and nephropathy. Furthermore, psychiatric symptoms and migraine may occur. Magnetic resonance imaging has identified contrast-enhancing cerebral lesions with surrounding vasogenic edema. Electron microscopy has shown alterations in the arterioles and capillaries consisting of multilayered basement membranes in brain, kidney, and skin biopsies. Linkage analysis has mapped the disease locus to chromosome 3p21. At the present time, no effective treatment is known. This article gives a summary of the clinical, morphological, genetical, and pathological characteristics of HERNS.

Brain↗
PubMed2005

[Mechanical recanalization in acute stroke treatment].

The development of endovascular techniques for the treatment of acute stroke began with the introduction of local intra-arterial fibrinolysis. In parallel to designing new systemic therapy approaches, catheter systems for loosening, disintegrating, or removing cerebral thrombi have undergone assessment in recent years to serve as alternatives or supplements to fibrinolytic treatment. Mechanical alteration of intracranial thrombi with balloon catheters, manipulations with the guide wire, or ultrasound waves transmitted into the vascular system as well as techniques for thrombus aspiration, snare extraction, or more complex hydrodynamic or laser-guided thrombectomy systems have been tested in feasibility studies, which evidenced basic functionality and relative safety. Broad clinical applications outside of the clinical trial setting cannot yet be recommended since the new catheter systems are still in early phase clinical testing.

Acute Disease↗
PubMed2005

[Stenting in acute stroke].

Hemodynamic impairment caused by pseudo-occlusion or occlusion of the internal carotid artery (ICA) is a rare etiology of stroke. Acute revascularization of the vessel can restore the flow to the brain. This retrospective study shows that ICA stenting with proximal and distal protection devices in patients with acute stroke and pseudo-occlusion or occlusion of the ICA is technically feasible and can prevent further hemodynamic strokes. In contrast, selected patients have a high risk of reperfusion syndrome with intracranial hemorrhage and peri-interventional monitoring of blood pressure in an ICU is recommended.

Acute Disease↗
PubMed2005

Fibrous cap thickness and smooth muscle cell apoptosis in high-grade carotid artery stenosis.

OBJECTIVE: There is growing evidence that, in high-grade internal carotid artery (ICA) stenosis, continuous fibrous cap thinning is not mandatory for plaque rupture and symptom development. The possibility that smooth muscle cell (SMC) apoptosis is involved in loss of fibrous cap volume has only been examined in a limited number of patients with high grade carotid artery stenosis. METHODS: Endarterectomy specimens from n = 38 consecutive patients undergoing surgery for high-grade ICA stenosis (> or = 70%) were transversely sectioned at 2 mm intervals. Plaque instability was defined clinically, by a history of recent ischemic symptoms (< 60 days before surgery; n = 19) attributable to the stenosis, or histopathologically by the presence of plaque rupture (n = 14). Detailed morphometric analyses of the fibrous cap was based on routine stains; for DNA in situ end labeling the TUNEL technique was used. SMCs were identified by immunostaining for SMC actin. RESULTS: We found no significant difference between symptomatic/asymptomatic or ruptured/unruptured plaque with respect to various morphometric measures of the fibrous cap (i.e. mean area, number of plaque sections with fibrous cap, necrotic core-to-lumen distance at its thinnest or thickest part). The mean (+/- SD) apoptotic SMCs per thousand within the fibrous cap was significantly higher in symptomatic vs. asymptomatic (64.53 +/- 77.3 vs. 6.71 +/- 11.9; P<0.001) but not in ruptured plaques (43.3 +/- 64.4 vs. 30.1 +/- 60.9; P=0.117). CONCLUSIONS: These data suggest that continuous thinning of the fibrous cap is not an essential prerequisite for plaque rupture in ICA stenosis. Symptomatic, but not ruptured plaque, were associated with the highest number of apoptotic SMC. Thus, it seems unlikely that SMC apoptosis promotes plaque rupture by fibrous cap thinning.

Aged↗
PubMed2004

Endovascular recanalization of acute atherothrombotic carotid artery occlusion holds up progressive stroke.

In acute carotid artery occlusion, hemodynamic compromise in addition to artery-artery thromboembolism is the mechanism of ischemia that may lead to a progressive clinical course with enlarging infarcts. The natural course of carotid artery occlusion with a progressive stroke is unfavorable with only about 10% of patients making a good recovery. We report on two patients in whom emergency recanalization of acute carotid artery occlusion with self-expanding stents restored cerebral blood flow and held up progressive stroke.

Carotid Artery Thrombosis↗
PubMed2004

[Distal protection devices in carotid stent].

Endovascular treatment of carotid stenoses is increasingly used. Frequently temporary occlusion balloons or filters are placed distal to the stenosis to gain additional protection against cerebral emboli. There is still a scientific debate about the usefulness of such distal protection devices. The following contribution reviews existing techniques and their clinical results and should allow for a critical discussion and selection of current techniques and materials.

Angioplasty, Balloon↗
PubMed2004

[Stents in the treatment of intracranial atherosclerotic stenoses].

The treatment of intracranial atherosclerotic stenoses, which account for 10-15% of all ischemic strokes, is technically feasible for few years by the use of new flexible stent devices. Especially patients who fail best medical treatment have a poor prognosis and stenting becomes a reasonable treatment option. Herein we discuss treatment concepts and the principles of stent placement against the background of epidemiology and pathophysiologic basics.

Angiography, Digital Subtraction↗