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J B Fiebach

Publications and source records attributed to J B Fiebach.

At least 19 recordsLinked to original sources
PubMed2005

Cerebrovascular manifestations of Takayasu arteritis in Europe.

OBJECTIVES: Takayasu arteritis is well known as a cause of stroke in Asia but has rarely been described in the Western world. Here we report the clinical and neuroimaging follow-up of a series of patients with Takayasu arteritis from Europe. METHODS: Seventeen consecutive patients who fulfilled the diagnostic criteria for Takayasu arteritis of the American College of Rheumatology were evaluated on follow-up by standardized neurological examination, sonography and MRI. RESULTS: At follow-up almost 20 yr after onset of symptoms, the subclavian artery and the common carotid artery were often affected. In addition, evidence of intracranial pathology was found in seven patients. In contrast to the severe vessel involvement, the neurological state was stable. Two patients had suffered from stroke before the diagnosis was made and therapy was initiated, and one patient had recurrent transient ischaemic attacks. Intermittent dizziness was associated with pathology of the vertebral and basilar arteries. However, clinical symptoms of subclavian steal syndrome were rare. CONCLUSION: This case series shows that the clinical neurological course of Takayasu arteritis on treatment is benign in most cases despite the severe vascular involvement.

Adolescent↗
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

[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

[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↗
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

[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

CT and diffusion-weighted MR imaging in randomized order: diffusion-weighted imaging results in higher accuracy and lower interrater variability in the diagnosis of hyperacute ischemic stroke.

BACKGROUND AND PURPOSE: Diffusion-weighted MRI (DWI) has become a commonly used imaging modality in stroke centers. The value of this method as a routine procedure is still being discussed. In previous studies, CT was always performed before DWI. Therefore, infarct progression could be a reason for the better result in DWI. METHODS: All hyperacute (<6 hours) stroke patients admitted to our emergency department with a National Institutes of Health Stroke Scale (NIHSS) score >3 were prospectively randomized for the order in which CT and MRI were performed. Five stroke experts and 4 residents blinded to clinical data judged stroke signs and lesion size on the images. To determine the interrater variability, we calculated kappa values for both rating groups. RESULTS: A total of 50 patients with ischemic stroke and 4 patients with transient symptoms of acute stroke (median NIHSS score, 11; range, 3 to 27) were analyzed. Of the 50 patients, 55% were examined with DWI first. The mean delay from symptom onset until CT was 180 minutes; that from symptom onset until DWI was 189 minutes. The mean delay between DWI and CT was 30 minutes. The sensitivity of infarct detection by the experts was significantly better when based on DWI (CT/DWI, 61/91%). Accuracy was 91% when based on DWI (CT, 61%). Interrater variability of lesion detection was also significantly better for DWI (CT/DWI, kappa=0.51/0.84). The assessment of lesion extent was less homogeneous on CT (CT/DWI, kappa=0.38/0.62). The differences between the 2 modalities were stronger in the residents' ratings (CT/DWI: sensitivity, 46/81%; kappa=0.38/0.76). CONCLUSIONS: CT and DWI performed with the same delay after onset of ischemic stroke resulted in significant differences in diagnostic accuracy. DWI gives good interrater homogeneity and has a substantially better sensitivity and accuracy than CT even if the raters have limited experience.

Acute Disease↗
PubMed2002

Effect of intravenous thrombolysis on MRI parameters and functional outcome in acute stroke <6 hours.

BACKGROUND AND PURPOSE: The goals of this study were to examine MRI baseline characteristics of patients with acute ischemic stroke (AIS) and to study the influence of intravenous tissue plasminogen activator (tPA) on MR parameters and functional outcome using a multicenter approach. METHODS: In this open-label, nonrandomized study of AIS patients with suspected anterior circulation stroke, subjects received a multiparametric stroke MRI protocol (diffusion- and perfusion-weighted imaging and MR angiography) within 6 hours after symptom onset and on follow-up. Patients were treated either with tPA (thrombolysis group) or conservatively (no thrombolysis group). Functional outcome was assessed on day 90 (modified Rankin Score; mRS). RESULTS: We enrolled 139 AIS patients (no thrombolysis group, n=63; thrombolysis group, n=76). Patients treated with tPA were more severely affected (National Institutes of Health Stroke Scale score, 10 versus 13; P=0.002). Recanalization rates were higher in the thrombolysis group (Thrombolysis in Myocardial Infarction criteria 1 through 3 on day 1; 66.2% versus 32.7%; P<0.001). Proximal vessel occlusions resulted in larger infarct volumes and worse outcome (P=0.02). Thrombolysis was associated with a better outcome regardless of the time point of tPA treatment (< or =3 hours or 3 to 6 hours) (univariate analysis: mRS < or =2, P=0.017; mRS < or =1, P=0.023). Age (P=0.003), thrombolytic therapy at 0 to 6 hours (P=0.01), recanalization (P=0.016), lesion volume on day 7 (P=0.001), and initial National Institutes of Health Stroke Scale score (P=0.001) affected functional outcome (mRS on day 90) positively (multivariate analysis). The time point of tPA therapy affected the recanalization rate (P=0.024) but not final infarct volume. CONCLUSIONS: In this pilot study, tPA therapy had a beneficial effect on vessel recanalization and functional outcome. Multiparametric MRI delineates tissue at risk of infarction in AIS patients, which may be helpful for the selection of patients for tPA therapy. tPA therapy appeared safe and effective beyond a 3-hour time window. This study delivers the rationale for a randomized, MR-based tPA trial.

Acute Disease↗
PubMed2001

Masking of vertebral artery dissection by severe trauma to the cervical spine.

STUDY DESIGN: A prospective case study was performed. OBJECTIVES: To illustrate the association of cervical trauma with vertebral artery dissection, and to propose a diagnostic and therapeutic algorithm for suspected traumatic vertebral artery dissection. SUMMARY OF BACKGROUND DATA: Vertebral artery dissection is a recognized but underdiagnosed complication of trauma to the cervical spine. Symptoms of spinal cord injury, however, may obscure those of vertebral artery dissection, presumably causing gross underdiagnosis of this complication. METHODS: All patients with vertebral artery dissection admitted to the authors' facility between 1992 and 1997 were screened for cervical trauma. RESULTS: This article presents four patients with severe trauma to the cervical spine, defined as luxation, subluxation, or fracture, in whom symptoms of vertebral artery dissection developed after a delay ranging from several hours to weeks. The traumatic vertebral artery dissection typically was located at the site of vertebral injury or cranial to it. One patient with fracture of the odontoid process survived symptom free without ischemic brain infarctions. Another patient survived with traumatic quadriplegia in addition to large cerebellar and posterior cerebral artery infarctions. Two patients died as a result of fulminant vertebrobasilar infarctions, both with only moderate impairment from the primary spinal cord injury. CONCLUSIONS: Early signs of vertebral artery dissection include head and neck pain, often localized to the site of intimal disruption, which may be disguised by the signs of the spinal injury. Early Doppler ultrasound and duplex sonography as a noninvasive screening method should be performed for patients with severe trauma to the cervical spine. In cases of vertebral artery dissection, immediate anticoagulation should be initiated. Traumatologists should be aware of this complication in evaluating patients with severe trauma of the cervical spine, and also for a variety of forensic reasons.

Adult↗
PubMed2001

Thrombolytic therapy for ischemic stroke--a review. Part I--Intravenous thrombolysis.

OBJECTIVE: Thrombolytic therapy for acute ischemic stroke was implemented into clinical routine 4 yrs ago. Unfortunately, at present <2% of eligible patients receive thrombolytic therapy. We present an overview of all hitherto completed trials of intravenous thrombolytic therapy for carotid artery stroke including recommendations for therapy and diagnostic procedures and their impact on patient selection and meta-analyses. DATA SOURCES: We performed an extensive literature search not only to identify the larger and well-known randomized trials but also to identify smaller pilot studies and case series. Trials included in this review, among others, are the National Institute of Neurologic Disorders and Stroke (NINDS) study, European Cooperative Acute Stroke Study I and II, and Alteplase Thrombolysis for Acute Noninterventional Therapy in Ischemic Stroke (ATLANTIS) A and B and two large meta-analyses, including the Cochrane Library report. CONCLUSION: Intravenous thrombolytic therapy with recombinant tissue plasminogen activator has demonstrated a significant benefit and has proven to be safe for patients who can be treated within 3-6 hrs after symptom onset. This benefit is at the cost of an increased rate of symptomatic intracranial hemorrhage without a significant effect on overall mortality. In general, the benefit of thrombolysis decreases and the risks increase with progressing time after symptom onset. Presently, thrombolytic therapy is still underutilized because of problems with clinical and time criteria, and lack of public and professional education to regard stroke as a treatable emergency. If applied more widely, thrombolytic therapy may result in profound cost savings in health care and reduction of long-term disability of stroke patients.

Fibrinolytic Agents↗
PubMed2001

Thrombolytic therapy for ischemic stroke--a review. Part II--Intra-arterial thrombolysis, vertebrobasilar stroke, phase IV trials, and stroke imaging.

OBJECTIVE: Intra-arterial thrombolytic therapy for carotid and vertebrobasilar stroke may result in a more rapid clot lysis and higher recanalization rates than can be achieved with intravenous thrombolysis and thus may warrant the more invasive and time-consuming therapeutic approach. We present an overview of all hitherto completed trials of intra-arterial thrombolytic therapy for carotid and vertebrobasilar artery stroke including recommendations for therapy and a meta-analysis. Furthermore, new imaging techniques such as diffusion- and perfusion-weighted magnetic resonance imaging and their impact on patient selection are discussed. Finally, phase IV trials of thrombolysis in general and cost efficacy analyses are presented. DATA SOURCES: We performed an extensive literature search not only to identify the larger and well-known randomized trials but also to identify smaller pilot studies and case series. Trials included in this review, among others, are the PROACT I and PROACT II studies and the Cochrane Library report. CONCLUSION: Intra-arterial thrombolytic therapy of acute M1 and M2 occlusions with 9 mg/2 hrs pro-urokinase significantly improves outcome if administered within 6 hrs after stroke onset. Seven patients need to be treated to prevent one patient from death or dependence. Vertebrobasilar occlusion has a grim prognosis and intra-arterial thrombolytic therapy to date is the only life-saving therapy that has demonstrated benefit with regard to mortality and outcome, albeit not in a randomized trial. New magnetic resonance imaging techniques may facilitate and improve the selection of patients for thrombolytic therapy. Presently, thrombolytic therapy is still underutilized because of problems with clinical and time criteria, and lack of public and professional education to regard stroke as a treatable emergency. If applied more widely, thrombolytic therapy may result in profound cost savings in health care and reduction of long-term disability of stroke patients.

Fibrinolytic Agents↗
PubMed2001

Stroke magnetic resonance imaging within 6 hours after onset of hyperacute cerebral ischemia.

We studied the diagnostic and prognostic value of diffusion- and perfusion-weighted magnetic resonancce imaging (DWI and PWI) for the initial evaluation and follow-up monitoring of patients with stroke that had ensued less than 6 hours previously. Further, we examined the role of vessel patency or occlusion and subsequent recanalization or persistent occlusion for further clinical and morphological stroke progression so as to define categories of patients and facilitate treatment decisions. Fifty-one patients underwent stroke magnetic resonance imaging (DWI, PWI, magnetic resonance angiography, and T2-weighted imaging) within 3.3 +/- 1.29 hours, and, of those, 41 underwent follow-up magnetic resonance imaging on day 2 and 28 on day 5. In addition, we assessed clinical scores (on the National Institutes of Health Stroke Scale, Scandinavian Stroke Scale, Barthel Index, and Modified Rankin Scale) on days 1, 2, 5, 30, and 90 and performed volumetric analysis of lesion volumes. In all, 25 patients had a proximal, 18 a distal, and 8 no vessel occlusion. Furthermore, 15 of 43 patients exhibited recanalization on day 2. Vessel occlusion was associated with a PWI-DWI mismatch on the initial magnetic resonance imaging, vessel patency with a PWI-DWI match (p < 0.0001). Outcome scores and lesion volumes differed significantly between patients experiencing recanalization and those who did not (all p < 0.0001). Acute DWI and PWI lesion volumes correlated poorly with acute clinical scores and only modestly with outcome scores. We have concluded on the basis of this study that early recanalization saves tissue at risk of ischemic infarction and results in significantly smaller infarcts and a significantly better clinical outcome. Patients with proximal vessel occlusions have a larger amount of tissue at risk, a lower recanalization rate, and a worse outcome. Urgent recanalization seems to be of utmost importance for these patients.

Aged↗
PubMed2000

Poliomyelitic-like illness in central European encephalitis.

Central European encephalitis (CEE) may be accompanied by myeloradiculitic symptoms in up to 5% of patients. The authors report six patients with a myelitic form of CEE mimicking acute poliomyelitis with bulbar and arm predominance and a poor prognosis. Three patients died. Of the survivors, only one can perform most activities of daily living, but still needs assisted ventilation at night. Autopsy in one patient showed severe cervicothoracic inflammation with changes almost exclusively in anterior horn cells and roots, as typically seen in poliomyelitis.

Adult↗