Michael Kettner
Saarland University
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Publication
Featured researches published by Michael Kettner.
Jacc-cardiovascular Interventions | 2013
Christian Roth; W. Reith; Silke Walter; Stefanie Behnke; Michael Kettner; Julio Viera; Umut Yilmaz; Maria Alexandrou; M. Politi; Panagiotis Kostopoulos; Heiko Körner; Christoph Krick; Anton Haass; Klaus Fassbender; P. Papanagiotou
OBJECTIVES This study sought to assess the feasibility and safety of a recently described technique of mechanical recanalization with the help of a stent-like device. BACKGROUND In the special group of acute stroke patients with an intracranial large vessel occlusion, intravenous tissue-type plasminogen activator on its own leads to a good clinical outcome (mRS ≤ 2) in only 15% to 25% of cases. The aforementioned technique of mechanical recanalization showed very promising clinical results. METHODS Forty patients presenting within 6 h from stroke symptom onset were enrolled. Mechanical recanalization was performed using a Solitaire FR revascularization device. The primary endpoint of the study was the clinical outcome rated with the help of the modified Rankin Scale (mRS) after 90 days. RESULTS Twenty-four patients (60%) showed a good clinical outcome (mRS ≤ 2) at 90 days. One symptomatic hemorrhage was detected on follow-up computed tomography. The death rate was 12.5% (5 patients). Successful recanalization (Thrombolysis In Cerebral Infarction score ≥ 2b) of the target vessel was achieved in 95% of the patients with a mean of 1.8 runs with the device. CONCLUSIONS The ReFlow (Mechanical Recanalization With Flow Restoration in Acute Ischemic Stroke) study shows that mechanical recanalization with flow restoration is highly effective in stroke patients with a large intracranial vessel occlusion presenting within 4.5 h after symptom onset. (Mechanical Recanalization With Flow Restoration in Acute Ischemic Stroke [ReFlow]; NCT01210729).
Journal of Neuroimaging | 2016
Lenka Schwindling; Andreas Ragoschke-Schumm; Michael Kettner; Stefan Helwig; Matthias Manitz; Safwan Roumia; Martin Lesmeister; I. Q. Grunwald; Klaus Fassbender
An ambulance equipped with a computed tomography (CT) scanner, point‐of‐care laboratory, and telemedicine capabilities (Mobile Stroke Unit [MSU]) has been shown to enable delivery of thrombolysis to stroke patients at the emergency site, thereby significantly decreasing time to treatment. However, the MSU frequently assesses patients with cerebral disorders other than stroke. For some of these disorders, prehospital CT scanning may also be beneficial.
Cerebrovascular Diseases | 2016
Iris Q. Grunwald; Andreas Ragoschke-Schumm; Michael Kettner; Lenka Schwindling; Safwan Roumia; Stefan Helwig; Matthias Manitz; Silke Walter; Umut Yilmaz; Eric Greveson; Martin Lesmeister; W. Reith; Klaus Fassbender
Background: Recently, a mobile stroke unit (MSU) was shown to facilitate acute stroke treatment directly at the emergency site. The neuroradiological expertise of the MSU is improved by its ability to detect early ischemic damage via automatic electronic (e) evaluation of CT scans using a novel software program that calculates the electronic Alberta Stroke Program Early CT Score (e-ASPECTS). Methods: The feasibility of integrating e-ASPECTS into an ambulance was examined, and the clinical integration and utility of the software in 15 consecutive cases evaluated. Results: Implementation of e-ASPECTS onto the MSU and into the prehospital stroke management was feasible. The values of e-ASPECTS matched with the results of conventional neuroradiologic analysis by the MSU team. The potential benefits of e-ASPECTS were illustrated by three cases. In case 1, excluding early infarct signs supported the decision to directly perform prehospital thrombolysis. In case 2, in which stroke was caused by large-vessel occlusion, the high e-ASPECTS value supported the decision to initiate intra-arterial treatment and triage the patient to a comprehensive stroke center. In case 3, the e-ASPECTS value was 10, indicating the absence of early infarct signs despite pre-existing cerebral microangiopathy and macroangiopathy, a finding indicating the programs robustness against artefacts. Conclusions: This study on the integration of e-ASPECTS into the prehospital stroke management via a MSU showed for the first time that such integration is feasible, and aids both decision regarding the treatment option and the triage regarding the most appropriate target hospital.
Cerebrovascular Diseases | 2017
Michael Kettner; Stefan Helwig; Andreas Ragoschke-Schumm; Lenka Schwindling; Safwan Roumia; Isabel Keller; Daniel Martens; Johann Kulikovski; Matthias Manitz; Martin Lesmeister; Silke Walter; Iris Q. Grunwald; Thomas Schlechtriemen; W. Reith; Klaus Fassbender
Background: An ambulance equipped with a computed tomography (CT) scanner, a point-of-care laboratory, and telemedicine capabilities (mobile stroke unit [MSU]) has been shown to enable the delivery of thrombolysis to stroke patients directly at the emergency site, thereby significantly decreasing time to treatment. However, work-up in an MSU that includes CT angiography (CTA) may also potentially facilitate triage of patients directly to the appropriate target hospital and specialized treatment, according to their individual vascular pathology. Methods: Our institution manages a program investigating the prehospital management of patients with suspicion of acute stroke. Here, we report a range of scenarios in which prehospital CTA could be relevant in triaging patients to the appropriate target hospital and to the individually required treatment. Results: Prehospital CTA by use of an MSU allowed to detect large vessel occlusion of the middle cerebral artery in one patient with ischemic stroke and occlusion of the basilar artery in another, thereby allowing rational triage to comprehensive stroke centers for immediate intra-arterial treatment. In complementary cases, prehospital imaging not only allowed diagnosis of parenchymal hemorrhage with a spot sign indicating ongoing bleeding in one patient and of subarachnoid hemorrhage in another but also clarified the underlying vascular pathology, which was relevant for subsequent triage decisions. Conclusion: Defining the vascular pathology by CTA directly at the emergency site may be beneficial in triaging patients with various cerebrovascular diseases to the most appropriate target hospital and specialized treatment.
Radiologe | 2014
W. Reith; S. Bodea; Michael Kettner; R. Mühl-Benninghausen; A. Simgen
Degenerative alterations of the spine occur in an individual-specific manner with increasing age. This is not only dependent on external factors, such as hard physical labor over many years but can also be genetically influenced as demonstrated in recent studies. The spinal cord is well-protected within the spinal canal but can be impaired by degenerative alterations of the intervertebral discs and functional spinal segments. Depositions or narrowing of nerve structures can cause lasting pain or focal neurological deficits, such as paralysis or sensitivity disorders. These complaints can slowly develop over years, e.g. by a gradually increasing bony narrowing of the spinal canal (spinal canal stenosis) or can occur suddenly, e.g. an acute herniated disc. However, low back pain is much more common and occurs in approximately 80 % of people sometime during their lifetime. It is necessary to recognize the normal age-related anatomical alterations in magnetic resonance imaging (MRI), particularly for intervertebral discs in order to interpret these correctly. Knowledge of the spectrum of the various age-related degenerative processes which can occur in intervertebral discs and vertebral bodies is necessary to be able to differentiate them from pathological alterations. This is important because therapy decisions are often made as a direct result of MRI.
Radiologe | 2014
W. Reith; S. Bodea; Michael Kettner; R. Mühl-Benninghausen; A. Simgen
Degenerative alterations of the spine occur in an individual-specific manner with increasing age. This is not only dependent on external factors, such as hard physical labor over many years but can also be genetically influenced as demonstrated in recent studies. The spinal cord is well-protected within the spinal canal but can be impaired by degenerative alterations of the intervertebral discs and functional spinal segments. Depositions or narrowing of nerve structures can cause lasting pain or focal neurological deficits, such as paralysis or sensitivity disorders. These complaints can slowly develop over years, e.g. by a gradually increasing bony narrowing of the spinal canal (spinal canal stenosis) or can occur suddenly, e.g. an acute herniated disc. However, low back pain is much more common and occurs in approximately 80 % of people sometime during their lifetime. It is necessary to recognize the normal age-related anatomical alterations in magnetic resonance imaging (MRI), particularly for intervertebral discs in order to interpret these correctly. Knowledge of the spectrum of the various age-related degenerative processes which can occur in intervertebral discs and vertebral bodies is necessary to be able to differentiate them from pathological alterations. This is important because therapy decisions are often made as a direct result of MRI.
Radiologe | 2012
W. Reith; Michael Kettner; A. Simgen; Umut Yilmaz
Spinal dural arteriovenous fistulas are rare spinal vascular malformations which can cause progressive paraparesis and paraplegia if not treated. As symptoms are unspecific diagnosis is often delayed and clinical outcome is dependent on early therapy. While magnetic resonance imaging (MRI) is the first choice imaging procedure, selective spinal digital subtraction angiography is necessary to analyze the angioarchitecture and to plan the treatment. This article provides an overview on the epidemiology, etiology, clinical aspects and imaging features as well as therapeutic aspects of spinal dural arteriovenous fistulas. Knowledge of spinal vascular anatomy is the basis for understanding spinal dural arteriovenous fistulas.
Radiologe | 2012
W. Reith; Michael Kettner; A. Simgen; Umut Yilmaz
Spinal dural arteriovenous fistulas are rare spinal vascular malformations which can cause progressive paraparesis and paraplegia if not treated. As symptoms are unspecific diagnosis is often delayed and clinical outcome is dependent on early therapy. While magnetic resonance imaging (MRI) is the first choice imaging procedure, selective spinal digital subtraction angiography is necessary to analyze the angioarchitecture and to plan the treatment. This article provides an overview on the epidemiology, etiology, clinical aspects and imaging features as well as therapeutic aspects of spinal dural arteriovenous fistulas. Knowledge of spinal vascular anatomy is the basis for understanding spinal dural arteriovenous fistulas.
Current Atherosclerosis Reports | 2018
Silke Walter; I. Q. Grunwald; Stefan Helwig; Andreas Ragoschke-Schumm; Michael Kettner; Mathias Fousse; Martin Lesmeister; Klaus Fassbender
Purpose of ReviewAcute stroke is a treatable disease. Nevertheless, only a minority of patients obtain guideline-adjusted therapy. One major reason is the small time window in which therapies have to be administered in order to reverse or mitigate brain injury and prevent disability. The Mobile Stroke Unit (MSU) concept, available for a decade now, is spreading worldwide, comprising ambulances, fully equipped with computed tomography, laboratory unit and telemedicine connection to the stroke centre and staffed with a specialised stroke team. Besides its benefits, this concept adds a relevant amount of costs to health services.Recent FindingsThe feasibility of the MSU and its impact on reducing treatment times have been proven by several research trials. In addition, pre-hospital stroke diagnosis including computed tomographic angiography analysis facilitates correct triage of patients, needing mechanical recanalization, thereby reducing the number of secondary or inter-hospital transfers. Even so, the concept is not yet fully implemented on a broad scale. One reason is the still open question of cost-effectiveness. There are assumptions based on the randomised trials of MSUs hinting towards an acceptable amount of money per quality-adjusted life years and overall cost-effectiveness. Up to now, neither a prospective analysis nor a consideration of secondary transfer avoidance is available.SummaryThe MSU concept is an innovative and impactful strategy to improve stroke management, especially in times of constraints in healthcare economics and health care professionals. Prospective information is needed to answer the cost-effectiveness question satisfactorily.
Radiologe | 2014
W. Reith; S. Bodea; Michael Kettner; R. Mühl-Benninghausen; A. Simgen
Degenerative alterations of the spine occur in an individual-specific manner with increasing age. This is not only dependent on external factors, such as hard physical labor over many years but can also be genetically influenced as demonstrated in recent studies. The spinal cord is well-protected within the spinal canal but can be impaired by degenerative alterations of the intervertebral discs and functional spinal segments. Depositions or narrowing of nerve structures can cause lasting pain or focal neurological deficits, such as paralysis or sensitivity disorders. These complaints can slowly develop over years, e.g. by a gradually increasing bony narrowing of the spinal canal (spinal canal stenosis) or can occur suddenly, e.g. an acute herniated disc. However, low back pain is much more common and occurs in approximately 80 % of people sometime during their lifetime. It is necessary to recognize the normal age-related anatomical alterations in magnetic resonance imaging (MRI), particularly for intervertebral discs in order to interpret these correctly. Knowledge of the spectrum of the various age-related degenerative processes which can occur in intervertebral discs and vertebral bodies is necessary to be able to differentiate them from pathological alterations. This is important because therapy decisions are often made as a direct result of MRI.