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P D Schellinger

Publications and source records attributed to P D Schellinger.

At least 19 recordsLinked to original sources
PubMed2006

[Intracerebral hemorrhage related to anticoagulant therapy].

Intracerebral hemorrhage (ICH) is the most serious complication of oral anticoagulant therapy (OAT). The growing use of OAT has resulted in an increase of fatal ICH. The mortality rate is about 65%, and most of the surviving patients remain disabled. While improvements in the treatment of spontaneous ICH have recently been described, there are no internationally accepted guidelines for managing patients with OAT-ICH. Therefore, identifying effective treatments is essential for improving clinical outcome. This article reviews the epidemiology of OAT-ICH, its pathophysiology, and current treatment options and discusses open questions with particular respect to more recent pharmacological therapies.

Anticoagulants↗
PubMed2005

[Acute cerebral circulation problems].

Acute stroke is the third most common cause of death and also the most common cause of permanent disability in industrialized countries. Ischemic stroke is caused by occlusion of a cerebral artery leading to a critical reduction in brain perfusion in the respective brain area (penumbra). Most acute stroke treatment strategies are based on the penumbra concept: attaining rapid and persistent reperfusion is followed by the protection of critically ischemic and not yet infarcted (penumbral) tissue by, e.g., neuroprotection. Examination of the acute stroke patient includes a brief history, neurostatus and imaging (CT or MRI) for the exclusion of intracerebral hemorrhage. The diagnostic standard is CT; modern stroke MRI protocols provide an improved selection in later time windows. Intravenous thrombolysis with rt-PA within 3 h of symptom onset is the only approved therapy with a proven significant benefit for the patient. The effect is smaller but still significant if treatment occurs up to 4.5 h, and may still be present in MRI selected patients up to 9 h. More aggressive forms of therapy include interventional reperfusion techniques and therapy of malignant MCA infarction such as hemicraniectomy and hypothermia, which at present, however, are not routine and are only performed in specialized centers.

Acute Disease↗
PubMed2005

[Heat stroke with alpha coma. A case report].

We report the case of a near-fatal heat stroke in a 41-year-old patient. The comatose patient had a body core temperature of 41.5 degrees C. The clinical course was complicated by systemic inflammatory response syndrome and multiorgan failure. The EEG showed an alpha coma that did not react to external stimuli and, in general, has a poor prognosis. The patient regained consciousness and was discharged from our intensive care unit after 16 days. In the further course cerebral toxoplasmosis developed which was treated with a combination therapy of sulfadiazine and pyrimethamine. The patient was transferred to a neurorehabilitation clinic with a moderate neurological deficit 65 days after heat stroke onset.

Adult↗
PubMed2005

[Diffusion and perfusion MR imaging in stroke].

Magnetic resonance imaging (MRI) in stroke makes it possible to visualize the initial infarct in cases of acute cerebral ischemia. Perfusion MRI serves to determine which tissues are additionally at risk of infarction due to persistent hypoperfusion. MRI also allows those examiners with limited experience to reliably confirm an infarct. The most important differential diagnosis of cerebral ischemia, intracerebral hemorrhage, can likewise be recognized with certainty using MRI. Although diffusion and perfusion MRI only demonstrate the pathophysiology of cerebral ischemia approximately, the method is suited for identifying those patients who would profit from reperfusion therapy. Whether MRI is also appropriate as an aid to reaching a prognosis on the risk of secondary hemorrhage has not yet been resolved.

Brain↗
PubMed2004

Magnetic resonance imaging criteria for thrombolysis in acute cerebral infarct.

BACKGROUND AND PURPOSE: Magnetic resonance imaging (MRI) selection of stroke patients eligible for thrombolytic therapy is an emerging application. Although the efficacy of therapy within 3 hours after onset of symptoms with intravenous (IV) tissue plasminogen activator (tPA) has been proven for patients selected with computed tomography (CT), no randomized, double-blinded MRI trial has been published yet. SUMMARY OF REVIEW: MRI screening of acute stroke patients before thrombolytic therapy is performed in some cerebrovascular centers. In contrast to the CT trials, MRI pilot studies demonstrate benefit of therapy up to 6 hours after onset of symptoms. This article reviews the literature that has lead to current controlled MRI-based thrombolysis trials. We examined the MRI criteria applied in 5 stroke centers. Along with the personal views of clinicians at these centers, the survey reveals a variety of clinical and MRI technical aspects that must be further investigated: the therapeutic consequence of microbleeds, the use of magnetic resonance angiography, dynamic time windows, and others. CONCLUSION: MRI is an established application in acute evaluation of stroke patients and may suit as a brain clock, replacing the currently used epidemiological time clock when deciding whether to initiate thrombolytic therapy. MRI criteria for thrombolytic therapy are applied in some cerebrovascular centers, but the results of ongoing clinical trials must be awaited before it is possible to reach consensus.

Brain↗
PubMed2004

[Value of modern CT-techniques in the diagnosis of acute stroke].

BACKGROUND: Thrombolysis is the treatment of choice for acute stroke within 3 h after symptom onset. Treatment beyond the 3 h time window has not been shown to be effective in any single trial, however, metaanalyses suggest a somewhat less but still significant effect within 3 to 6 h after stroke. It seems reasonable to apply improved selection criteria that allow to differentiate the patients with a relevant indication for thrombolytic therapy from those who have not. While stroke MRI seems to be the upcoming standard, due to its low availability the need for an improved CT-based patient selection is evident. METHODS: The present literature on imaging in stroke has been thoroughly reviewed. The diagnostic strengths and weaknesses of conventional CT, CT angiography (CTA), CTA source image analysis (CTA-SI) and perfusion CT (PCT) for an acute diagnostic stroke workup are critically reviewed in this article. The authors present their view about a comprehensive diagnostic approach to acute stroke in accordance to stroke MRI findings, which allows to challenge the rigid therapeutic time window and improve patient management. CONCLUSION: Information about the presence or absence of ICH by non contrast CT and vessel occlusion by means of CTA is deemed obligatory before rt-PA is given in the 3-6 hour time window. Clear demarcation of an early hypodensity exceeding 1/3 of the MCA territory on NCCT or CTA-SI should preclude thrombolytic therapy. The irreversibly damaged infarct core and the ischemic but still viable thus salvageable tissue at risk of infarction as seen on CT/CTA/CTA-SI/PCT should be obtained before thrombolysis is initiated within 3-6 hours. Once these advanced techniques are used, the therapeutic time window can be extended with acceptable safety. However, comprehensive informed consent is mandatory, especially when thrombolytic therapy is considered beyond established time windows.

Cerebral Angiography↗
PubMed2004

[The value of platelet inhibitors in the secondary prophylaxis of stroke -- a review].

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.

Aspirin↗
PubMed2004

Clopidogrel in the management of cerebrovascular events.

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.

Arteriosclerosis↗
PubMed2003

Effect of incomplete (spontaneous and postthrombolytic) recanalization after middle cerebral artery occlusion: a magnetic resonance imaging study.

BACKGROUND AND PURPOSE: Early reperfusion is one of the best predictors of good outcome after acute middle cerebral artery (MCA) occlusion. The purpose of this study was to analyze the frequency and relevance of incomplete recanalization for tissue and clinical outcome. METHODS: From a larger acute stroke database (Kompetenznetzwerk Schlaganfall B5), all patients (n=82) with MCA main stem occlusion (excluding carotid T-occlusions) were selected. These patients had received a multiparametric stroke MRI protocol including diffusion- and perfusion-weighted imaging (DWI, PWI) and MR angiography (MRA) within 6 hours after symptom onset, at day 1 and after 1 week. Recanalization status was determined with MRA on day 1 (according to Thrombolysis In Myocardial Infarction flow grades) and used to group patients into those with persistent occlusion (0) or minimal (1), partial (2), or complete (3) recanalization. RESULTS: Incomplete recanalization according to MRI criteria was found in 39 patients (grade 1: n=20; grade 2: n=19), complete recanalization in 10, and persistent occlusion in 33. There was no statistically significant difference in any of the clinical (National Institutes of Health Stroke Scale score) or MRI baseline parameters (DWI lesion, PWI deficit, mismatch volume, mismatch ratio). However, lesion growth was smaller in patients with recanalization (even in patients with only minimal recanalization) and outcome was related to the degree of recanalization (mean modified Rankin score at 90 days: 3.36, 2.70, 1.79, and 1.44 for the groups with no, minimal, partial, and complete recanalization, respectively). Both incomplete and complete recanalization was more frequent in patients receiving thrombolysis. CONCLUSIONS: Incomplete recanalization on day 1 is a frequent MR finding after MCA main stem occlusion, indicating a more favorable clinical course than persistent occlusion. MR indicators of early recanalization could be useful surrogates of efficacy in thrombolytic trials.

Adult↗
PubMed2003

MRI in acute subarachnoid haemorrhage; findings with a standardised stroke protocol.

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.

Adult↗
PubMed2003

[Hepatic encephalopathy].

Hepatic encephalopathy (HE) is a neuropsychiatric complication of acute and chronic liver disease. Its etiology and pathogenesis are thought to be a complex, metabolically induced, and therefore potentially reversible disturbance in brain functions. The diagnosis is based on demonstrating both a disorder of the central nervous system and a concomitant liver disease as well as the exclusion of any neurological or psychiatric disorder of other etiology. The diagnosis of HE is clinical and displays a wide spectrum of neuropsychiatric symptoms in different degrees of severity. Ancillary diagnostic workup includes laboratory tests, neuroimaging, and neurophysiological exams such as electroencephalography and evoked potentials. The therapy of HE mainly consists of treatment and avoidance of any precipitating conditions such as high protein intake, infections, and gastrointestinal bleeding. Other therapeutic approaches modulate metabolic processes such as ammonium synthesis and excretion, formation of neurotransmitters, and as a last resort liver transplantation. The prognosis depends ultimately on the course of the liver disease.

Cerebral Cortex↗
PubMed2003

[Modern magnetic resonance techniques in stroke].

In industrialized nations, stroke is the most common cause of permanent disability and need of care. Causal treatment is possible only during the first few hours following the stroke, in the form of systemic fibrinolysis. An exact diagnosis of the causative pathology must be made before starting the therapy, and this must happen in the shortest possible period of time. Using imaging techniques, the whole spectrum of differential diagnoses of cerebral ischemia must be covered, including above all intracerebral and subarachnoid hemorrhage. Although computed tomography (CT) is excellently suited for determining hemorrhage, infarct can be recognized with much better contrast using diffusion-weighted magnetic resonance (MR) imaging (DWI). Stroke MR imaging additionally allows the representation of vital "tissue at risk"of infarction using perfusion images as well as the recognition of vessel occlusion using MR angiography. This paper is intended to define the usefulness of DWI in comparison to CT techniques and to elucidate the use of diffusion coefficients for differentiating the various stages of infarction. Besides presenting an explanation of the basic principles of modern stroke MR imaging, typical results of MR perfusion measurements and the appearance of hemorrhages on MR will be explained.

Brain Ischemia↗
PubMed2002

Serial analysis of the apparent diffusion coefficient time course in human stroke.

Acute cerebral ischemic injury can be rapidly detected on diffusion-weighted images. The apparent diffusion coefficient (ADC) depends on the stage of cytotoxic edema and water content in the infarcted parenchyma. The purpose of this study is to determine the time course of ADC during the first days of ischemic stroke. These data should make it possible to distinguish between multiple stroke and a single progressive infarction. Eight patients with clinically diagnosed acute cerebral ischemia were examined by diffusion-weighted MRI from 2 to 20 h after onset of symptoms. Daily control scans were performed for up to 10 days. ADC values were analyzed from 55 MRI studies. Furthermore, ADC was measured in the tissue which showed a hyperintense signal at the first examination and in the contralateral tissue. White and gray matter were analyzed separately. Data were expressed as the ratio ADC (rADC) of lesion to control region of interest. All patients showed a uniform reduction in rADC from the first hours of stroke and decreasing to the 3rd day. The rADC increased again from the 4th day up to the point of pseudo-normalization on day 9. The gray matter showed a slightly faster increase than the white matter. rADC shows significant changes in the first days after stroke, following a rather uniform time course. Together with T2-weighted MRI this makes it possible to differentiate between hyperacute, acute, and chronic stroke. Furthermore, the age of an ischemia can be determined and multiple strokes can be distinguished from a single progressive stroke.

Aged↗
PubMed2002

[Modern nuclear magnetic resonance techniques in stroke].

In industrialized nations, stroke is the most common cause of permanent disability and need of care. Causal treatment is possible only during the first few hours following the stroke, in the form of systemic fibrinolysis. An exact diagnosis of the causative pathology must be made before starting the therapy, and this must happen in the shortest possible period of time. Using imaging techniques, the whole spectrum of differential diagnoses of cerebral ischemia must be covered, including above all intracerebral and subarachnoid hemorrhage. Although computed tomography (CT) is excellently suited for determining hemorrhage, infarct can be recognized with much better contrast using diffusion-weighted magnetic resonance (MR) imaging (DWI). Stroke MR imaging additionally allows the representation of vital "tissue at risk" of infarction using perfusion images as well as the recognition of vessel occlusion using MR angiography. This paper is intended to define the usefulness of DWI in comparison to CT techniques and to elucidate the use of diffusion coefficients for differentiating the various stages of infarction. Besides presenting an explanation of the basic principles of modern stroke MR imaging, typical results of MR perfusion measurements and the appearance of hemorrhages on MR will be explained.

Humans↗
PubMed2002

[Myxedema coma as a rare differential diagnosis of severe consciousness disturbance].

Myxedema coma is a rare and life-threatening complication of untreated hypothyroidism. Therefore, it must be part of the differential diagnosis in comatose patients. We report one patient who presented with CO(2) narcosis,hypothermia, bradycardia,hyporeflexia, tetraparesis, ascitis, pleural effusions, and heart insufficiency. Examination of the CSF, cranial CT, MRI, and MR angiography were normal. In suspicion of myxedema coma,the patient was treated with high dose L-thyroxine and hydrocortisone for preventing secondary adrenal insufficiency. A fast clinical recovery, decreased T4 (7.2 ng/l) and T3 (0.93 ng/l), and increased TSH (20.19 mU/l) together with the following anamnesis of radio iodine therapy and insufficient thyroxine intake confirmed the diagnosis. In conclusion, treatment of the myxedema coma must be started as soon as the laboratory results are confirmatory, since its course depends on the time of initiation of treatment.

Adrenal Insufficiency↗
PubMed2002

Thrombolytic therapy within 3 to 6 hours after onset of ischemic stroke: useful or harmful?

BACKGROUND: The use of recombinant tissue plasminogen activator (rtPA) within 3 hours after onset of an ischemic stroke is an established therapy. Because the use of intravenous rtPA beyond a time window of 3 hours after stroke onset is still a matter of debate, we sought to review the evidence for the use of thrombolytic therapy in a time window up to 6 hours after onset of symptoms of ischemic stroke. SUMMARY OF REVIEW: The meta-analyses of the major trials (National Institute of Neurological Disorders and Stroke rtPA Stroke Study, European Cooperative Acute Stroke Study [ECASS] I, ECASS II) showed a benefit of thrombolytic therapy with intravenous rtPA even within 6 hours after onset of symptoms of ischemic stroke. The rate of intracerebral hemorrhage was slightly increased in the 6-hour time window compared with the 3-hour time window (odds ratio, 3.23 versus 2.68), but this was without statistical significance because of wide confidence intervals. A positive effect of 37% relative odds reduction with the use of a dichotomization of < or =2 versus > or =3 on the modified Rankin Scale remains for rtPA treatment within 6 hours. However, the Alteplase Thrombolysis for Acute Noninterventional Therapy in Ischemic Stroke (ATLANTIS) Study, in which a 3- to 5-hour time window was used, failed to show a benefit of rtPA. Still, when the results of ATLANTIS are included into meta-analyses such as the Cochrane Library, the positive effect of rtPA treatment in the 6-hour time window remains, with a "number needed to treat" value of 11. Treating patients only within a 3- to 6-hour time window would lead to a number needed to treat value of 25. CONCLUSIONS: Consequently, from our point of view it appears unjustified to limit thrombolytic therapy to 3 hours. Because of lack of approvals for 3 to 6 hours, thrombolytic therapy within this time window should be done only as part of an institutional protocol after extensive information is obtained from the patient and the patient's relatives. Better methods for patient selection are required; in particular, newer MRI techniques, such as diffusion- and perfusion-weighted imaging, can play a key role. The aim is to qualify and individualize the time window according to the findings in each patient's imaging results rather than to use a strictly time-defined therapeutic window.

Brain Ischemia↗