Showing papers by "Peter D. Schellinger published in 2004"
TL;DR: Hyperacute ICH causes a characteristic imaging pattern on stroke MRI and is detectable with excellent accuracy and can rule out ICH and demonstrate the underlying pathology in hyperacute stroke.
Abstract: Background and Purpose— Although modern multisequence stroke MRI protocols are an emerging imaging routine for the diagnostic assessment of acute ischemic stroke, their sensitivity for intracerebral hemorrhage (ICH), the most important differential diagnosis, is still a matter of debate. We hypothesized that stroke MRI is accurate in the detection of ICH. To evaluate our hypotheses, we conducted a prospective multicenter trial. Methods— Stroke MRI protocols of 6 university hospitals were standardized. Images from 62 ICH patients and 62 nonhemorrhagic stroke patients, all imaged within the first 6 hours after symptom onset (mean, 3 hours 18 minutes), were analyzed. For diagnosis of hemorrhage, CT served as the “gold standard.” Three readers experienced in stroke imaging and 3 final-year medical students, unaware of clinical details, separately evaluated sets of diffusion-, T2-, and T2*-weighted images. The extent and phenomenology of the hemorrhage on MRI were assessed separately. Results— Mean patient age...
401 citations
TL;DR: The combination of noncontrast-enhanced CT (NECT), perfusion CT (PCT), and CT angiography (CTA) can render additional information within <15 minutes and may help in therapeutic decision-making if PWI and DWI are not available or cannot be performed on specific patients.
Abstract: Background and Purpose— We aimed to determine the diagnostic value of perfusion computed tomography (PCT) and CT angiography (CTA) including CTA source images (CTA-SI) in comparison with perfusion-weighted magnetic resonance imaging (MRI) (PWI) and diffusion-weighted MRI (DWI) in acute stroke <6 hours. Methods— Noncontrast-enhanced CT, PCT, CTA, stroke MRI, including PWI and DWI, and MR angiography (MRA), were performed in patients with symptoms of acute stroke lasting <6 hours. We analyzed ischemic lesion volumes on patients’ arrival as shown on NECT, PCT, CTA-SI, DWI, and PWI (Wilcoxon, Spearman, Bland-Altman) and compared them to the infarct extent as shown on day 5 NECT. Results— Twenty-two stroke patients underwent CT and MRI scanning within 6 hours. PCT time to peak (PCT-TTP) volumes did not differ from PWI-TTP (P=0.686 for patients who did not undergo thrombolysis/P=0.328 for patients who underwent thrombolysis), nor did PCT cerebral blood volume (PCT-CBV) differ from PWI-CBV (P=0.893/P=0.169). CTA...
313 citations
TL;DR: The authors investigated whether transient ischemic attacks (TIAs) before stroke can induce tolerance by raising the threshold of tissue vulnerability in the human brain and found that initial diffusion lesions tended to be smaller and final infarct volumes were significantly reduced (final T2: 9.1 [interquartile range, 19.7] versus 36.5 [91.2] mL; P=0.014).
Abstract: Background and Purpose— We investigated whether transient ischemic attacks (TIAs) before stroke can induce tolerance by raising the threshold of tissue vulnerability in the human brain. Methods— Sixty-five patients with first-ever ischemic territorial stroke received diffusion- and perfusion-weighted MRI within 12 hours of symptom onset. Epidemiological and clinical data, lesion volumes in T2, apparent diffusion coefficient (ADC) maps and perfusion maps, and cerebral blood flow and cerebral blood volume values were compared between patients with and without a prodromal TIA. Results— Despite similar size and severity of the perfusion deficit, initial diffusion lesions tended to be smaller and final infarct volumes were significantly reduced (final T2: 9.1 [interquartile range, 19.7] versus 36.5 [91.2] mL; P=0.014) in patients with a history of TIA (n=16). This was associated with milder clinical deficits. Conclusions— The beneficial effect of TIAs on lesion size in ADC and T2 suggests the existence of endo...
279 citations
TL;DR: The initial and exclusive use of MRI in patients with a stroke syndrome is feasible, probably cost-effective, and even time-saving when considering its potential wealth of information.
Abstract: The initial and exclusive use of MRI in patients with a stroke syndrome is feasible, probably cost-effective, and even time saving when considering its potential wealth of information. MRI may be the diagnostic tool of choice in patients with all stages of stroke, especially in the hyperacute assessment of ICH, and could be equivalent to CT and CTA in SAH diagnosis. The authors' aim is to provide a comprehensive review about the potential role of MRI in evaluating ICH and SAH. Emerging applications, such as the assessment of microbleeds as a risk factor for secondary hemorrhage after thrombolysis and perihemorrhagic ischemic changes as a potential marker for patients likely to benefit from hematoma evacuation, are reviewed.
158 citations
TL;DR: Stroke MRI within 6 h of symptom onset on five patients with minor subarachnoid haemorrhage (SAH) diagnosed by CT shows a characteristic pattern, and an aneurysm in only one patient.
Abstract: There is doubt as to whether acute haemorrhage is visible on MRI. We carried out MRI within 6 h of symptom onset on five patients with minor (low Hunt and Hess grades 1 or 2) subarachnoid haemorrhage (SAH) diagnosed by CT to search for any specific pattern. We used our standard stroke MRI protocol, including multiecho proton density (PD)- and T2-weighted images, echoplanar (EPI) diffusion- (DWI) and perfusion- (PWI) weighted imaging, and MRA. In all cases SAH was clearly visible on PD-weighted images with a short TE. In four patients it caused a low-signal rim on the T2*-weighted source images of PWI, and DWI revealed high signal in SAH. In the fifth patient SAH was perimesencephalic; susceptibility effects from the skull base made it impossible to detect SAH on EPI DWI and T2*-weighted images. Perfusion maps were normal in all cases. MRA and conventional angiography revealed an aneurysm in only one patient. Stroke MRI within 6 h of SAH thus shows a characteristic pattern.
72 citations
TL;DR: This review concentrates on giving the reader an integrated knowledge of the current status of thrombolytic therapy in stroke and develops a treatment algorithm based on pathophysiological information rendered by a multiparametric stroke magnetic resonance imaging protocol.
Abstract: Purpose of review Stroke is the third leading cause of death after myocardial infarction and cancer, and is the leading cause of permanent disability and disability-adjusted loss of independent life-years in western countries. Thrombolysis is the treatment of choice for acute stroke within 3 h after the onset of symptoms. We present an overview of a diagnostic approach to acute stroke management that allows the individualization of patient management based on pathophysiological reasoning and not rigid time windows established by randomized controlled trials. Recent findings This review concentrates in the first part on giving the reader an integrated knowledge of the current status of thrombolytic therapy in stroke, and in the second part develops a treatment algorithm based on pathophysiological information rendered by a multiparametric stroke magnetic resonance imaging protocol. Summary Thrombolysis is an effective therapy for ischemic stroke, whether performed intravenously within 3 h or intra-arterially within 3-6 h. Meta-analyses have provided evidence of an effect of intravenous thrombolysis beyond the 3 h time window, especially when improved selection criteria such as modern magnetic resonance imaging protocols are applied. Sadly, thrombolysis is still underused. Positive results from studies currently underway may encourage more centers to offer this therapy to an increasing number of stroke patients, and thereby reduce the considerable socioeconomic burden of stroke.
56 citations
TL;DR: Hypothermia improves survival and decreases infarct volume in wistar rats subjected to thromboembolic occlusion, and there were no significant differences between the use of rt-PA alone or in combination with hypothermia.
49 citations
TL;DR: An overview of a diagnostic approach to acute stroke management that allows the clinician to individualize patient management based on pathophysiologic reasoning and not rigid time windows established by randomized controlled trials is presented.
Abstract: Stroke is the third leading cause of death after myocardial infarction and cancer and the leading cause of permanent disability and of disability-adjusted loss of independent life-years in Western countries. Thrombolysis is the treatment of choice for acute stroke within 3 hours after symptom onset. Treatment beyond the 3-hour time window has not been shown to be effective in any single trial; however, meta-analyses suggest a somewhat less but still significant effect within 3 to 6 hours after stroke. It seems reasonable to apply improved selection criteria that would allow one to differentiate patients with a relevant indication for thrombolytic therapy from those who do not have one. We present an overview of a diagnostic approach to acute stroke management that allows the clinician to individualize patient management based on pathophysiologic reasoning and not rigid time windows established by randomized controlled trials. Therefore, this review concentrates on giving the reader an integrated knowledge of the current status of thrombolytic therapy in stroke and then develops a treatment algorithm based on pathophysiologic information rendered by a multiparametric stroke magnetic resonance imaging protocol.
33 citations
TL;DR: It is found that overall brain shape is probably strongly influenced by genetic effects but the variation in sulcal and gyral patterns is also affected by non-genetic influences to a considerable extent.
28 citations
TL;DR: In experimental herpes simplex virus encephalitis IL-6, as a potent mediator of neuronal injury, is upregulated in the acute but not in the chronic disease.
12 citations
TL;DR: The number of cases of decompression illness (DCI) reported within the United States more than doubled from 562 cases in 1986 to 1164 cases in 1994, and the number of diving-related inner ear incidents has increased as well.
Abstract: INTRODUCTION Sport diving is becoming more and more popular, with increasing numbers of people enjoying this sport. There are approximately six million sport divers in the United States with an increasing number of associated diving accidents. Between 1986 and 1994, the number of cases of decompression illness (DCI) reported within the United States more than doubled from 562 cases in 1986 to 1164 cases in 1994. Accordingly, the number of divingrelated inner ear incidents has increased as well. Inner ear decompression illness (IEDCI), which was thought to be a rare disease in sport divers, shows an increasing incidence, as does inner ear barotrauma (IEB). Both IEB and IEDCI can harm the inner ear function and lead to permanent inner ear dysfunction.
TL;DR: The authors analyse the results of recent trials and present ongoing or future trials with clopidogrel to answer the question, whether the combination therapy is safe in long‐term secondary stroke prevention and predicts up to tenfold higher cost in the prevention of vascular events.
Abstract: Summary
The inhibition of platelet function has proved its effectiveness in the reduction of vascular events in many large trials for many different compounds such as ASA, ticlopinin, dipyridamole or clopidogrel. In this overview, the authors analyse the results of recent trials and present ongoing or future trials with clopidogrel. Clopidogrel has proved its superiority in prevention of vascular events as compared to ASA, being even higher in high-risk groups such as diabetic patients. For the post-interventional treatment of patients undergoing stent-protected dilatation of coronary arteries, the combination of ASA and clopidogrel has become a standard procedure. There is also evidence that the combination of ASA and Clopidogrel is better than ASA alone in long-term treatment up to at least 9 months. The long-term combination therapy seems to be very promising and is currently analysed in three large trials in over 30 000 patients with a large number of stroke patients. These trials will also answer the question, whether the combination therapy is safe in long-term secondary stroke prevention. However, there is still a widespread reluctance in doctors to prescribe Clopidogrel for its costs. Cost-effectiveness studies predict up to tenfold higher cost in the prevention of vascular events when compared to ASA, in times of shrinking health budgets a topic of interest.
TL;DR: In this article, anwendung moderner bildgebender Verfahren kann die Patienten identifizieren, die am ehesten von einer Thrombolysetherapie auch auserhalb etablierter Zeitfenster profitieren.
Abstract: Hintergrund
Die intravenose Thrombolyse ist die Behandlung der Wahl fur akute Schlaganfallpatienten im 3-h-Zeitfenster. Metaanalysen zufolge besteht auch ein Behandlungseffekt jenseits der 3-h-Grenze, der aber kleiner ist („time is brain“). Die Anwendung moderner bildgebender Verfahren kann die Patienten identifizieren, die am ehesten von einer Thrombolysetherapie auch auserhalb etablierter Zeitfenster profitieren. Moderne Schlaganfall-MRT-Protokolle sind der aktuelle Goldstandard fur die akute Schlaganfalldiagnostik, sind im Gegensatz zu CT-basierter Diagnostik aber deutlich seltener verfugbar. Der Bedarf fur eine optimierte CT-Diagnostik bei Schlaganfallpatienten ist offensichtlich.
TL;DR: The combination of clopidogrel and ASA for cerebrovascular prevention should only be given within controlled studies or as an individual treatment with an accordingly acquired informed consent, and the combination of Dipyridamole/ASA should be primarily given to TIA/stroke patients with a lower cardiovascular comorbidity.
Abstract: Introduction The goal of secondary prophylaxis following cerebral ischemia is a long lasting inhibition of thrombogenesis to prevent recurrent stroke or other vascular events. Platelet inhibitors (PI) according to meta-analyses lead to a relative risk reduction (RRR) of 22 % for vascular events after stroke. The aim of this article is a summary and critical review of all relevant studies and meta-analyses for secondary prevention of stroke and to give a differentiated therapeutic recommendation. Methods We performed a careful and extensive review of the present literature for PI in the secondary prevention of stroke. Next to the classic meta-analyses such as the Antiplatelet Trialists' analysis, the relevant single trials (e. g. CATS, TASS, ESPS 2, CURE, CAPRIE) as well as meta-analyses and post hoc analyses of these studies are summarized and interpreted. Therapeutic recommendations are in consistence with the recommendations and guidelines of national (DGN), European (EUSI) and international (AHA/ASA) Groups/Associations. Also, the present literature was searched for new information with regard to side effects and pharmacological interactions and introduced into the review. Conclusions ASA reduces the RR after TIA/stroke by approximately 13 % and has the same efficacy with less side effects in lower dosages (50 - 325 mg/Tag). Ticlopidine is a reserve drug due to its unfavorable side effect profile (neutropenia, TTP). Clopidogrel is better than ASA (RRR 8.7 %) for vascular patients in preventing another vascular event (stroke, MI, vascular death). This effect is pronounced in patients at high risk for atherothrombotic events such as previous MI, cardiac surgery, or diabetes. Dipyridamole+ASA is better than ASA in patients with TIA/stroke (in indirect comparison also than Clopidogrel) for the secondary prevention of recurrent stroke (RRR 23 %), but not for the prevention of other vascular events. Therefore, Clopidogrel should be primarily given to patients with a high vascular risk (one or more cardiovascular risk factors) or to patients with ASA intolerance. Dipyridamole/ASA should be primarily given to TIA/stroke patients with a lower cardiovascular comorbidity. Studies for the combination of Clopidogrel/ASA (MATCH, CHARISMA) and for the comparison of both combinations (PRoFESS) are underway. At present, the combination of clopidogrel and ASA for cerebrovascular prevention should only be given within controlled studies or as an individual treatment with an accordingly acquired informed consent.
TL;DR: National and international committees and guidelines name IVT with rt-PA within the 3-hour time window as the first-line treatment of choice, and the European Stroke Initiative states “intravenous rT-PA (0.9 mg/kg) is the recommended treatment within 3 hours of onset of ischemic stroke (level I)”.
Abstract: To treat, or not to treat: that is the question: Whether ’tis nobler in the mind to suffer The uncertainties rendered by open case series, Or to take arms against a sea of troubles, And by performing adequate trials end them? — —Modified from William Shakespeare’s Hamlet (III, i)
At present, only intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator (rt-PA) administered within 3 hours after symptom onset is proven to be effective for the treatment of acute stroke. Based on level I evidence from the NINDS trial and several meta-analyses, rt-PA has been approved in many countries around the world, including the USA, Canada, Australia, and most of Europe. A recent meta-analysis (Marler et al, Lancet 2004, in press) also demonstrates a significant effect of rt-PA in the 3- to 4.5-hour window, albeit that has not changed approval regulations. National and international committees and guidelines name IVT with rt-PA within the 3-hour time window as the first-line treatment of choice. In specific, the European Stroke Initiative (EUSI) states “intravenous rt-PA (0.9 mg/kg, maximum 90 mg), with 10% of the dose given as a bolus followed by an infusion lasting 60 minutes, is the recommended treatment within 3 hours of onset of ischemic stroke (level I)” and “the benefit from the use of intravenous rt-PA for …